Thread locking compounds, sometimes referred to as ‘Loctite’ despite it being a brand name, is an adhesive that can be applied to the threads of a fastener to keep it from loosening over time from vibration or shifting parts. This is especially useful on smaller bolts that require a relatively low torque such as rotor bolts, but can be put to use anywhere that a bolt can repeatedly loosen even though it has been properly torqued. Lubricating a fastener with grease, the swear-by for cycling mechanics, is done to allow a bolt or nut to be precisely torqued, and to ease removal down the road. Grease and thread locking compounds should never be mixed. While there are other ways to keep bolts from coming loose – cotter pins, lock washers and even safety wire – none of those methods are suitable for use on our expensive and lightweight mountain bikes. Thread locking compound is a thixotropic fluid, which means that its properties change under certain circumstances. For most types of thread locker, especially the blue colored version that is used on bicycle parts, this refers to a lack of oxygen that allows the fluid to set once the fastener has been tightened down to the correct torque. It is best to allow the locking compound a full 24 hours to fully set, although it will dry sooner than that.
Thread locking compound is available in both a stick (left) and liquid (right) compound, and is used to keep bolts from backing off. It can be used in a number of places, including brake caliper and rotor bolts, or can come in especially handy on places like stem bolts if you spend your days doing hot laps in the bike park and want to keep your rig running safe.
Blue is your friend: Medium strength Loctite is most often blue in color and can be used on many places on a mountain bike to keep bolts from coming loose. It is thought of as being ‘removable’ in that it shouldn’t require excessive leverage or heat to break free, and requires roughly 115 in/lb of torque to loosen a typical bike-part fastener. It is available in a squeeze bottle with a needle tip that allows you to apply it only where needed, but it can also be bought in a tube, similar to a glue stick, that is great for applying to places where you don’t want it to run onto other surfaces (lever reach adjustment screws being a perfect example). Blue thread lock is ideally used on any steel fastener that has repeatedly loosened despite having having been tightened to the recommended torque. Safety is a primary reason for thread locking compounds, and international standards specify that brake rotor and caliper mounting hardware are treated with it so there is little if any chance of an improperly torqued fitting rattling loose. Same goes for shock mountain hardware or any threaded fitting on a rotating part. Thread locking compound is also the go-to for press-in or threaded parts that tend to develop creaks over time (a touch of blue thread locker on some clean BB threads, for example).
What not to use: Thread locker is available in different compounds and strengths that are usually color coded, although most are not suitable for use on a bike: red thread locker requires 230 in/lb to loosen and should be thought of as permanent, meaning that it will likely require a large leverage tool to remove the bolt. There is really no reason to be using the red colored compound anywhere on your bike. Green thread locker is best at penetrating into nooks and crannies, and can be used to hold sealed bearings in place (being careful to not get anywhere near the rubber seal) if the bearing bore is oversized. The green compound needs roughly 90 in/lb to crack lose, and should be used very sparingly.
Start by removing the trouble making bolt and giving it a thorough cleaning with an alcohol based spray, being sure to remove any old grease or grime. Do the same to the threads that accept the bolt, using a Q-tip if needed to clean it properly. Let it air dry and take a minute to inspect the bolt’s threads for damage or stretching that may have been caused by over tightening.
Apply a small amount, usually just one drop, to the threads on the bolt. There is no need to go overboard, too much will only make a mess.
Thread the bolt back in, tightening it to the specified torque. Wipe away any excess thread locker that may be present. It is recommended to let the bike sit for 24 hours before riding to allow the compound to fully set.
Where to not use thread locker: Although blue thread locker can be put to use on many places, there are some where it shouldn’t be applied. It should be avoided when working with titanium bolts, especially when they are being threaded into a dissimilar metal, such as steel or aluminum. Anti-seize is your best bet here because it will prevent galvanization, allowing you to easily remove the fastener down the road. We would also recommend that you skip using Loctite on aluminum bolts as well for the same reason, but it can also make removing fragile aluminum hardware difficult, leading to rounded or broken off heads. Here are some other places that shouldn’t see thread locker:
• Chain ring bolts, especially aluminum versions (use grease to allow you to loosen them later on) • Most crank set bolts (grease used here allows it to attain the proper torque) • Pedal threads (pedals won’t loosen due to their reverse threading, but using grease will eliminate creaks and make them easier to remove) • Axle threads on either front or rear thru-axles (grease here prevents the two aluminum surfaces from galling) • Any small hardware that hasn’t repeatedly loosened (M3 sized bolts or smaller, such as those used to attach the adjustment dials of a fork. Using thick grease here will prevent loosening and make them easier to remove)
How does a cassette work? A modern bike’s cassette, no matter how many speeds it has, slides onto the rear hub’s freehub body and is tightened down with a lockring. Splines on the freehub body ensure that the cassette’s shift ramps are properly aligned as the manufacturer intended. The hub’s clutch mechanism, the part that allows you to coast or put down power, is built into the freehub body itself, meaning that the cassette can be removed without having to dive into the hub’s internals. Removing the cassette involves loosening the lockring with a special splined tool while holding the cassette with a chain whip, a type of long wrench with a section of actual chain on the end that engages the cog’s teeth. While removing the cassette isn’t included in routine maintenance, it does allow for easier cleaning of the drivetrain.
The cassette is made up of cogs, some separate and some on a carrier as shown above, that feature notches that mate with splines on the freehub body.
Some helpful pointers before you begin: • While both SRAM and Shimano cassettes can often be removed with the same tool, there are a number of different lockring tools that may or may not be best suited to your hub depending on the configuration. Your best bet is to take your rear wheel into your local shop and have them show you which model is ideal. • Lay out the cogs and spacers on your workbench in the exact order that they were removed in. Your bike won’t shift correctly if a spacer is installed in the wrong position. • If installing a new cassette take note of the order of its parts when removing it from the box. • Although we didn’t show it below, the wheel’s quick release skewer can be used to hold the lockring tool in place while you crack it loose. This is especially helpful if the engagement between the tool and lockring is shallow, as can sometimes be the case. • Be careful not to cross thread the lockring while reinstalling the cassette. Doing so can sometimes damage the threads on the freehub, which opens a can of worms on the entire repair. Likewise, aluminum lockrings can be fragile – take your time. • If installing a new cassette it is important to also use the new lockring if the new smallest cog is of a different size to the old one (11 and 12 teeth are the most common sizes). Eleven tooth cogs use a smaller diameter lockring than larger twelve tooth versions. Using the twelve tooth sized lockring on an eleven tooth cog will prevent the chain from fully engaging the threads, causing it to skip under load while in the highest gear.
You’ll need a chain whip, lockring tool and large adjustable wrench to do this job, although a vice can be used in place of the wrench.
Step 1 – Remove the rear wheel from the frame and slide out the skewer, being careful not to lose the centering springs on each side. Install the splined lockring tool so that it is fully seated into the notches. If the engagement is quite shallow and the lockring tool is hollow you can use the QR skewer to hold it in place by reinstalling it through the hub and tool and snugging it down. Some lockring tools feature a pin that takes the place of a skewer.
Step 2 – Install the chain whip, making sure that the tool is fully engaged with the cog. The purpose of the chain whip is to hold the cassette/freehub from spinning while you loosen the lockring. If you are facing the cassette you will want the handle of the tool extending to the right as shown above.
Step 3 – It is now time to loosen the lockring. With the wheel face up on the workbench use a large crescent to turn the lockring tool counter clockwise while pulling the chain whip clock wise to hold the cassette/freehub in place. Apply even pressure to prevent the chain whip from jumping off of the cog, but if it does so repeatedly it likely means that that particular cog is so worn that the tool is actually slipping off. Move up to a larger cog and try again. If you’ve used the QR skewer to help hold lockring in place you’ll need to remove it in order to further loosen the lockring once it’s been cracked free.Some overly tight lockrings may require a bit of body english in order to crack them loose. If this is the case place the wheel upright on the ground in front of you with the cassette facing away. While standing over the wheel, with the tools in the orientation shown above, use your body weight as an aid to help loosen the lockring by pushing down on both the wrench and chain whip.
Step 4 – Unthread the lockring and set aside. Slide the cogs up and off of the freehub, taking note of where each spacer sits, and lay them out on the workbench in a safe spot. They need to go back on in the exact order that they were removed for your bike to shift properly.Cassettes can sometimes become stuck on aluminum freehub bodies due to the them gouging into the softer metal. This is common when the steel cogs are spaced separately instead of attached to a carrier that spreads out the load better. A screwdriver can be used to gently pry the cogs loose (be careful not to bend them), or used to tap them loose from the back side with a hammer.
Step 5 – Now is a great time to give the cogs and freehub body a proper cleaning, but be sure not to misplace any spacers while doing so. Inspect the cassette for any broken teeth or burs that can be cleaned up with a file.
Step 6 – Take note of the freehub’s splines and the notches on the cogs before reinstallation. The cogs will only slide onto the cassette in one orientation thanks to an odd sized spline that is slightly smaller in thickness than the rest. This ensures that the cassette’s shift points will all line up as they were designed to. The spline and corresponding notch are shown above circled in red.
Step 7 – While there is always debate about giving the freehub a light coating of grease or anti-seize, we don’t ever recommend doing so. Neither will prevent the cassette from gouging into the freehub body, and a steel cassette and freehub body has very little chance of corroding enough to ever become rusted together (that same goes for aluminum cassettes and F/H bodies as well). What the grease will do, though, is attract dirt and grime and make a mess of things. The only place where a small dab of grease or anti-seized should be used is on the lockring threads to allow it to be loosened easier down the road.
Step 8 – Align the cogs correctly and slide them down onto the freehub body, being careful to install everything in the exact order required – spacers included. Some cassettes will use a large ‘carrier’ that many of the cogs are attached to, turning them into a single unit, while some others may use separate cogs throughout the entire cluster.
Step 9 – Some cassette and hub combinations, especially those fitted with 10 speed cassettes, will result in the last (smallest) cog not engaging the freehub’s splines fully until pressure is applied. Make sure that the last cog is properly aligned before pressing it down with one hand while threading the lockring clockwise with the other until it is snug.
Step 10 – Take a close look to make sure that the cassette is spaced evenly before using a wrench to fully tighten the lockring. Look from the rear while slowly rotating the cassette. If you spot any wobbles or unevenness between the cogs you’ll need to disassemble the cassette and find your mistake.
Step 11 – Finish tightening the lockring by using a crescent wrench to turn it clockwise until it is quite snug. A torque of at least 360 inch/pounds is recommended. The QR skewer can once again be used to hold the tool in place (not shown).
I have a couple of these to do this morning in the busy Auckland Workshop here at NH so i thought i would make this weeks Workshop tip Cup and Cone Basics. enjoy!
How do they work? A cup and cone hub makes use of loose ball bearings and allows you to easily adjust bearing tension, unlike most sealed bearing hubs that don’t allow for any adjustment. They consist of the “cup” that acts as the bearing’s outer race, which is pressed into the hub shell and not replaceable, and the “cone” that serves as the inner race and threads onto the axle. The hub bearings, which are usually 1/4″ in rear hubs and 3/16″ in front hubs, spin between the cup and cone. Bearing tension is adjusted be threading the cone down on the axle, and then locking its position in place with the locknut (a spacer between the cone and locknut allows you to tighten the two against each other easily). Front cup and cone hubs are usually symmetrical, although the hub will be offset slightly to compensate for its rotor disc rotor mounting. Rear hubs use a freehub (the clutch mechanism that allows you to coast) and the driveside cone and locknut can be found set within, sometimes hidden from view.
From left to right: the cone (notice the wrench flats), spacer and locknut, with the axle in the background.
Why cup and cone? Because the majority of high-end aftermarket hubs use sealed bearings it’s common to think of a cup and cone hub as lower quality, but that isn’t always the case – Shimano’s top tier XTR hubs are an example – and there are actually some advantages to going with a loose ball hub set. Not only are they easier to service (if you’re into that sort of thing) once you know how to do it, not requiring any bearing press tools and a vice or hammer, but because bearing tension is adjustable you can dial in the perfect amount tension. On top of that, a well setup cup and cone hub that has been put together with proper grease will usually offer lower rolling resistance that sealed bearing hubs can only dream of. It has also been said that a cup and cone system offers far more lateral bearing support than sealed bearings, although most riders would be hard pressed to notice the difference.
Most cup and cone hubs use a rubber dust shield (left) to help keep the elements out. Remove it to expose the hub’s locknut and cone wrench flats (right)
Where do they lose points to sealed bearing hubs? Cup and cone systems often require more maintenance and can be prone to loosening up under hard riders, especially from sideways landings. This can be an especially big issue because the hub’s outer bearing race – the cup – and the inner race – the cone – can be easily damaged when ridden lose. The cup itself is pressed into the hub shell and is not replaceable, meaning that the entire hub can quickly be turned to scrap metal if it becomes pitted, whereas it is quite rare to damage a sealed bearing hub’s bearing bore from riding it loose. Worn out and lose sealed bearings? Simply pop them out, press in news ones and call it a day.
The cone and locknut are tightened up against each other, with a thin spacer in between, to lock them in place.
Some helpful pointers before you begin:
• Always use the smallest cone wrenches the fit. Most front hubs will accept either 13, 15 or 17mm sizes, while rear hubs often take 15, 17 and 19mm size wrenches. A crescent wrench can be used on the outer locknut. • Turning the axle with your fingers will give you much better indication of if it is too tight than spinning it in the frame or fork. But rocking the wheel laterally while it is still in the bike will allow you to easily feel if it is too loose. • It is important to note that adjusting the hub bearings tighter than required will not in any way keep them from coming loose sooner, but will actually increase wear on all components. A loose ball hub that has been ridden with too much bearing tension will likely have damaged both the cone and cup, possibly requiring the hub to be replaced. The same will result from riding a hub that is too loose. Your goal should be to adjust the hub so that it has the least amount of bearing tension without being loose.
The hub’s loose ball bearings roll on the cup, a concave and pressed in piece that acts as the outer bearing race. Both the cup and the cone’s bearing surface must be in good shape in order for the wheel to turn smoothly, with even the smallest amount of pitting causing a noticeable amount of roughness. Different grade hubs also use differing qualities of bearing surfaces – XTR hubs will turn smoother than lower level product.
Step 1 – Checking Bearing Tension: While the wheel is still in the frame or fork, hold the tire and rock it back and forth laterally. Tthe hub may be loose by only the slightest amount, but this is exaggerated by the time the movement reaches the rim and tire. Your hub bearings will need to be adjusted if you feel any slop. Remove the wheel from the bike if you don’t feel any play, pull out the quick release and turn the axle slowly with your fingers. Any roughness that is felt will mean that the bearing tension is too high and will need to be backed off, or that a rebuild must be performed. Check to be sure that both sides’ locknut and cone are tight against each other before moving on to the next step – if not, all of your work will be for nothing.
Step 2: To adjust bearing tension you’ll first need to break the locknut and cone free from each other. Do this on the non-disc side if working on a front hub, or the disc side if working on a rear hub. Position the two cone wrenches so that squeezing them together will turn the locknut to the left (as shown above), but try to keep the inner wrench’s position the same. Once the locknut is loose, turn the cone wrench clockwise to tighten, or anti-clockwise to loosen, a few degrees and hold it in place as you tighten the locknut back down onto it. Check for play by trying to rock the axle with your fingers. It should turn smoothly, but have close to zero free play. Repeat as necessary.
Step 3: If the hub is close to being perfect, but still needs a slight adjustment, you can do so without loosening the locknut once again. If it needs to be tightened, place a cone wrench on each locknut (not the cones!) and give them the slightest clockwise turn – only a degree or two – and recheck. If bearing tension needs to be back off slightly you can turn the cones out against each other by simply putting a cone wrench on each one and turning anti-clockwise.
Ride better through knowledge….
Bike Mechanic / Fleet Manager
0800 444 144 / 09 257 4673
Like to get Workshop Wednesday delivered to your inbox every week?
Sign up here for weekly biking adventures + top maintenance tips + gear reviews from the Natural High team.
Yesterday I rode one of the 29ers we have in our fleet here at Natural High for the first time, as a 26″ purest I thought it was high time i saw what all the fuss was about! Well let me tell you I was very impressed and it got me thinking with the introduction of the 650B whats the best to run with?
I think I will let you decide…..
With the widespread adoption of the 29er mountain bike in manufacturing and the mountain bike community, the growing debate of 29er vs. traditional 26″ mountain bikes is getting hot amongst riding groups. If you are in the market to upgrade your current mountain bike or get into the sport, your options are wider than ever which is a good thing for the sport but can be debilitating when looking to purchase a new rig.
Due to recent changes in the industry, the 650B mountain bike platform (also known as 27.5) has been growing in popularity. This article was originally written in 2011 and has now been updated to include the 650B wheel size. You can see the addition down below.
There is no “right answer” for every mountain biker, so let’s take a look at the 26″ vs. 650B vs. 29er mountain bike debate and see where it shakes out in my opinion. This topic is probably the most debated in the industry, so you will find that every rider has what they think is the right answer for you (typically what they bought).
THE 29ER MOUNTAIN BIKE: WHAT IS THE BIG DEAL?
Before we get into what will work best for you, let’s take a look at this larger wheel size and see how it affects the mountain bike in a general way.
What does a 29er do well?
Rolls over rocks and roots easier due to the wider circumference.
More distance covered per pedal revolution.
Higher air volume in tires smooth out ride.
The larger diameter wheels of the 29er mountain bike can create the sensation of having an 1″ more travel than the bike is spec’ed due to the larger air volume and larger contact patch with the ground. For this reason, it has become the go to size for much of the hard tail and shorter travel mountain bikes in the industry. The racing world has really embraced the larger wheels size for these benefits it brings to the trail.
What are the drawbacks of a 29er?
Large size equals larger weight.
Harder to maneuver in tight, twisty single track.
Longer travel (5.5″ and higher) 29ers feel REALLY big.
Sizing and geometry issues with smaller riders.
Larger radius needs stiff wheel build and fork to prevent deflection.
Just as with any big change, it is not all good news. While the true 29er zealots will probably tell you these things are not true, the reality is that you are adding bigger wheels to the mountain bike than traditional 26″, so there are going to be negative side affects that go along with the positive changes.
650B MOUNTAIN BIKES: WHAT IS DIFFERENT?
The 650B wheel size literally cuts the difference between the 29er and 26 wheel size in half at 27.5″. When you think about what the 650B platform in mountain biking does, it is actually pretty easy. It averages the strengths and weaknesses between the two sizes. You get some of the benefits of 29ers without the size and you get some of the nimbleness of 26 while increasing the ability to roll over objects.
What does a 650B (27.5) do well?
Rolls over rocks and roots easier due to the wider circumference over 26″.
More distance covered per pedal revolution.
Higher air volume in tires smooth out ride.
Brings a bigger wheel size to longer travel platforms.
At this time, 650B based frames, forks and tires are hard to come by (but that is changing quickly)
What are the drawbacks of a 650B?
Large size equals larger weight but lighter than an equivalent 29er.
Sizing and geometry issues if you are going to try to convert your 26 to 650B.
Larger radius needs stiff wheel build and fork to prevent deflection.
26″ VS. 650B VS. 29″ WHEELS: WHICH IS RIGHT FOR ME?
When you are taking a look at the 26″ vs. 650B vs. 29er mountain bike, there are several personal questions you need to ask yourself as you make your decision. As with all things, there is no right answer that fits all people. How you ride your bike and how you want it to react is the most important factor when making this decision…not what your friend bought and says is the best.
So here is how I see it shake out…
HOW TALL ARE YOU?
As the distance from your head to the ground increases, the 29er wheel size actually becomes more proportional to your size. Riders in the 6 foot and up crowd that are looking for a XC to light AM mountain bike should test ride a 29er just to see how they like it. You might find that it fits perfectly and you have finally found a bike that feels like it actually fits. Shorter riders in the 5’6″ range and lower will need to take a serious look at geometry and test ride different frames as they might find the bike feels too big or isn’t able to maneuver as well. I have known shorter riders that have loved the bigger wheel size, but that is typically in hard tail applications.
The 650B wheel size does an interesting thing in this situation. It can bring that proportion that the taller riders see down to mid level height riders in the mid 5 foot to 6 foot range. It can also bring a 29er like experience to shorter riders that are used to riding small bikes.
Taller Riders: Yes on 29er and 650B
Mid Height Riders: Yes on 29er, 650B and 26
Shorter Riders: Maybe/No on 29er; Yes on 650B and 26
HOW MUCH TRAVEL ARE YOU LOOKING FOR?
While the argument that a 29er “adds an inch” of travel is almost true in theory, there is a big difference in 140mm forks and 160mm forks in mountain biking. The thicker stanchions and construction make a huge difference for riders looking to get into the more technical side of riding. If you are in the market for a 140mm or 160mm travel mountain bike, a 120″ travel 29er is not going to give you that same stiffness and confidence from a bike build and component standpoint. Also, as you move up in travel the bike feels bigger and when you add in the larger wheel diameter, that gets multiplied and can hold you back in slow tech and DH situations.
However, if you are looking at lighter 130mm to 140mm travel 26″ mountain bikes and you are taller, the 120mm travel 29er might be a great option. It will roll over technical rocks and roots on most single track easier and you will still be able to keep the overall bike weight under 30 pounds in most cases.
The 650B platform is bringing thicker stanchion, longer travel forks to the bigger wheel market. It is almost as if 650B wheels were made specifically for “enduro” style riding.
In the short travel and hard tail mountain bike market, the 29er mountain bike has almost completely taken over. This recommendations are used in conjunction with the height recommendations above.
HT and 100mm travel and under: 29er or 650B
120mm to 130mm: 29er or 650B
140mm: 650B or 26″
150mm to 160mm: 650B or 26″
WHAT TYPE OF TRAILS DO YOU RIDE?
As mentioned before, 29er mountain bikes do take more to maneuver through tight single track. If all of your riding is filled with tight turns in trees, you will want to try out a 29er on your own local trails before making a decision. On the other side of the spectrum, if your trails are more open and rocky, the 29er wheel size can really excel and bring more speed as you can hit sections faster.
Do a lot of racing and forest service road riding? A 29er is almost a no brainer in those situations. If you don’t believe me…just try to keep up with a 29er rider on a FSR. This adds up with the shorter travel and hard tail mountain bike market. Even 650B bikes will be no contest for a short travel 29er in these situations. If you are looking for a bike that will do a lot of things well and you ride a wide variety of trails (assuming you can only own one bike), the 650B platform might be a great “do it all” option.
Tight and twisty: 26″ and 650B
Open and rocky: 650B and 29er
Racing and FSR: 29er
WHAT DO I PERSONALLY USE? 29ER OR 26″ OR 650B?
When I spec out my personal mountain bikes given trail conditions, this is how everything lays out for me personally given my specs. I would describe my riding style as technical/enduro. I like to find the nasty lines possible and make them ridable at speed. For this reason, I typically like to ride mountain bikes with big forks and more travel, but I also like to dip into the XC and race side every now and then as I have a background in those applications. At 6’1″ tall, I fall into the taller side of the sizing spectrum in between large and x-large. To fit my need to find all tech riding, I am on large size mountain bikes to keep the bike easier to move in slow tech.
Singlespeed and Hard Tails: 29er
Short Travel Race Bikes (100mm and under): 29er
Trail bike (140mm and 150mm): 650B
As of right now, I have not found a 29er mountain bike that has been able to handle what I want to throw at a 140mm travel or higher mountain bike. It has not been agile enough and the 32mm stanchion forks mated with higher radius wheels are not built to withstand the abuse. Given the specs of 29ers, I do not see this changing for me as a rider.
On the shorter travel end, there are a lot of advantages of the larger wheel size that have made a couple of 29ers the fastest bikes I have ever ridden for those applications. I doubt if I will ever go back to 26″ wheels for anything under 140mm worth of travel. The 650B is almost completely tailored to the largest percentage of my riding and brings a larger wheel size without compromises to my ideal travel range at 140mm to 150mm. I get the benefits of a larger wheel without having to sacrifice geometry or stiffness of components. While 26″ would still be the choice for dedicated DH rigs, 650B is taking over trail bike duties while 29ers take up the XC side of things.
WHAT IS THE RIGHT BIKE FOR YOU?
As you take a look at all of these specs, you have to look inward at your body type and riding style to see which wheel size will be the best option for you. There is no right option for everyone and the 29er wheel size is not going to take over the mountain biking industry like a lot of the Kool-Aid drinkers are trying to say. The larger wheel diameter does have some serious advantages in certain situations, but it also does not work for others.
The best option…test ride your top 26″ candidate on your local trail and the top 29er candidate if they are available. I would also swing a leg over a 650B bike to see if that platform works for you…especially in one mountain bike quiver situations. Although, at this point in time, that demo might be hard to line up.
If they aren’t, find the closest substitute. At the end of the day, you are the one making the investment in your mountain bike and you will be the one riding it…not everyone else that is trying to inject their opinion in your buying decision. There are a lot of riders that are going to scream that one platform is better than the other. The reality is that all riders are different and that is why we have so many options. Take an honest look at how you use your bike and what body type you are. This is the only way you will get the right wheel size for you while trying to ignore the fanbois.
Well with Another Busy Season behind us here at Natural High its that time again folks! Workshop Wednesday is back! keep an eye out for some Handy tips and tricks, industry info and everything Bicycles.
Workshop Wednesday will also be venturing into the world of Video this term so keep an eye out for the links in the coming weeks! exciting….
This week we talk about Cables and Housing..
Given that they control the shifting (and often the braking as well) of your bike, cables and housing most certainly don’t get the respect that they deserve. We often take it for granted that a shift cable will almost never fail during a ride, or that, barring wear and tear, its housing will assuredly never come apart. That feeling of security comes from many decades worth of manufacturing experience and has resulted in the relatively inexpensive cable becoming an unsung hero of the modern mountain bike. Jagwire’s Tech Support Specialist Ben Oliver has been working with cables, hoses, and housing for the past fifteen years, including wrenching for professional cycling teams around the globe, and here he sheds some light on this often overlooked subject.
What exactly are a shift cables and housing made of?
Shift cables are typically made using nineteen steel wire strands, either galvanized or stainless. An inner core is created using seven strands with an additional twelve wrapped around the outside in a slight spiral.Shift housing features four layers. From the inner-most layers out, they include: • a polymer inner liner, which may or may not be lubricated • a shell made of linear steel strands • another polymer layer that stabilizes the linear shell • and an outer layer of housing that faces the elements
A dissected view of shift housing
Is there really a difference between brake and shift housing?
There is a critical difference in the inner shells of brake and shift housing. Brake housing has a shell of coiled, flat wound wire wrapped around the inner liner. This wound wire flexes slightly to resist the significantly higher load that brake cables put on housing. This flexing would wreak havoc on shifting performance because it doesn’t deliver the precision movement needed for clean shifts.Shift housing resists this flexing by using linear strands of wire that run the length of the housing parallel to the shift cable. These wires experience much lighter loads, but are designed to keep the housing from compressing, resulting in clean, crisp shifting. If you’ve ever tried to use shift housing in place of brake housing you’ve seen what a poor substitute it is. The force of braking will either cause the linear strands of wire to compress and bow out or simply split the housing into pieces.
All this, not to mention the cables and housings for each application are of vastly different size, are reasons to never switch up the two.
The same view of a section of brake housing.
And why is it that shift cables are made from spiral steel strands instead of a simpler straight wire?
Cables today are made from spiral steel wires to deliver strength and durability, while still remaining flexible. A single or series of straight wires would be extremely stiff and vulnerable to breaking when curved.
We’ve all seen cables rust, but could this cause them to fail?
Rust can obviously be a cause, but most frequently it’s general fatigue and wear. When overused or installed incorrectly, cables can fray due to movement against cables guides, tight bends in the frame or shifter, etc…
How is the cable “head” attached to the cable, and why is it the shape it is?
The shape of the cable head is dictated by the individual OEM component manufacturers. Mountain bike brake cables have settled on something fairly standard, whereas road components have a couple different types of cable heads for both shift and brake.The attachment of the cable head is accomplished by first cutting the cable, then spot welding the end. Once complete, the welded end is “punched,” causing the individual strands of the cable to mushroom out. This mushrooming allows the cable head to be forged around and through the strands making it extremely strong and resistant to being pulled off the cable during braking or shifting.
Shift cables are often used to control dropper seat posts as well.
Mechanics often use the phrase “cable stretch.” What does this mean, and is it all down to the cable or does housing play a part?
In general, cables today are all pre-stretched. The “cable stretch” phenomenon has more to do with housing compression that occurs after installing new cables.If you’ve ever put on new brake cables and housing you know the way to finish everything off is to give the lever several hard squeezes. This compresses the flat-wound wire and “stretches” the housing. There’s a noticeable change in lever feel once this has been done.
It’s less of an issue with derailleur cables and housing, but it’s still good practice to get any settling that the cables and housing are going to do out of the way before you send a new bike out on its maiden voyage. This can be difficult if the bike uses internal cable routing. But again, it’s usually not as dramatic on shift cables, and if it does occur all it takes is a simple twist of a barrel adjuster to take up the slack.
Today’s bikes, as advanced as they may be, still seem to be able to creak just as bad and as often as those from many years ago. Sure, we may have cutting edge suspension, nearly maintenance free disc brakes and enough carbon components to make an F1 car jealous, but our state of the art machines will often have the most curious noises emanating from who knows where. How can this be? And what causes these god awful sounds that can make us want to abandon our expensive bikes in the bush and walk home?
Those noises, often referred to as a “creak”, are usually the result of two components shifting under load against each other. While it can sometimes be as simple as the seat post within the frame or the handlebar and stem clamp, it is more common to have the noise be a result of two threaded components not being properly torqued down to the manufacturer’s spec, allowing them to shift ever so slightly when you push hard on the pedals or lean into a turn. The tricky bit is that the part doesn’t actually have be loose to make the noise – the actual movement may be exceedingly small – which can mean that it may be difficult to track down. Add in a bit of dust, grime or water to the joint between the two and you’ll have the perfect environment to make what will quickly become the world’s most annoying sound.
You may need to use a number of different tools in order to track down and remove that pesky noise, but a torque wrench and some grease will help you the most.
Safety warning: The good news is that creaks are often not a major issue, but rather just your bike telling you that it’s time to take a day off from riding and give it some love. The bad news is that that isn’t always the case, with the noise sometimes signalling that you have a cracked frame or a part that is close to complete failure. This is why it is important to not let those creaks and groans go unnoticed for long. Not to scare you, but that sound could quite literally be a warning that your head tube is about to depart from the rest of your bike, or that your lightweight two piece crankset is close to becoming a three piece unit. Spending a few minutes tracking down the sound may just save you from having to search for your front teeth mid-ride, or at the very least a long walk of shame out of the bush with your broken steed on your back.
Finding the cause: The two most important weapons in fighting the war against noise are grease and knowing the proper torque, but often the most difficult part is tracking it down – it usually isn’t as easy as just listening to where the noise is coming from. Mountain bikes, especially those that are built around an aluminum frame, are really good at helping the sound to resonate from its origin. It may sure as hell sound like that tick is coming from your rear wheel, but don’t be surprised when you find that your stem was the source all along. While a creak can come from pretty much anywhere that a component is clamped or threaded into another part, including a front derailleur band or even a water bottle cage bolt, there are a few common offenders. For this reason it helps to know a some tricks on how to isolate the noise and make it easier to find…
Some helpful pointers before you begin:
• Proper torque is key to eliminating creaks and groans. Check out Park Tool’s page on torque specs, and be sure to find out what your components require. • Depending on the component, you may need to use grease, lube or Loc-tite to stop a noise. It is important to not only use the right one, but to also wipe away any extra that may be present after reinstallation. It will only attract grime and cause even more noise. • Tools you may need include a hex set, torx wrench, bottom bracket tool and a torque wrench, among others.
Bottom bracket, crankarms and pedals: These are the most common offenders of them all. Head out onto a quiet side street and pedal hard against your brakes while standing up (standing will eliminate your saddle and post). You don’t have to go fast, it’s the torque from your legs that will cause noise, not how fast you’re going. Listen carefully for the noise during the hard downstroke of each pedal revolution – that is when it will be most likely to occur. Found the culprit? Start by crossing out the easiest causes first. Remove your pedals and give the threads on both the arms and on the spindles a cleaning, applying a dab of grease to each before reinstalling. Head out for another ride to see if the noise is still there, and if it is the next step is to remove the crankarms and bottom bracket from the frame. Spend a few minutes cleaning everything so that it looks as good as new – using a solvent will help. Be sure to read the manufacturer’s instructions before reinstalling the components, and also lay on a coating of grease to the crank spindle, as well as the threads on both the BB shell and BB cup. Remember that torquing each part to the recommended amount is key to eliminating noise.
Often one of the trickiest to spot, chainring bolts can make quite a racket when slightly loose. Aluminum chainring bolts are even more prone to noise. If you’ve done all the steps above, but still have a noise when standing and pedalling under load, it may be the these little guys. Remove one at a time, cleaning and putting a small dab of grease on the threads before reinstalling. Never use Loc-tite on chainring bolts – it isn’t needed and will make life difficult down the road.
Spokes and nipples: When you hear a mechanic say that the “wheel has lost its tension” he is referring to the spokes becoming looser than is ideal, allowing the wheel to flex more under load. This is also likely to allow the spokes and nipples to shift slightly, even if they don’t feel loose to the touch, and it’s this shifting that can cause noise. Before re-tensioning wheel, something that should only be done by someone who has experience working with wheels, drip a small amount of lube into the nipple hole at the rim, as well as at the hub and where the spokes cross. A wax based lube will dry and leave a residue that will last much longer than a teflon based lube. Be careful not to let any drip onto your brake rotor.
Saddle and post: If you suspect that the noise may be coming from your saddle clamp or the post into the frame, pedal hard under load (dragging the brakes can help) while seated and then while standing. If the creak disappears when you are out of the saddle there is a good chance that it is one of the above. Begin by marking or measuring your saddle height before removing the post, followed by a good cleaning of the inside of the seat tube (including under the seat post clamp) and the post itself. Reinstall after applying a thin coating of grease or non-slip compound to the inside of the seat tube, post and under the seat post clamp. It also makes sense to remove the saddle from the post and clean the clamping surfaces as well.
Rear suspension: A coil spring that doesn’t have enough preload applied to it, letting it shift on the spring clip and collar, will also be prone to making noise. This is a good place to start, much easier than removing and greasing pivot bolts, if you push down on your bike’s rear suspension and it makes a groan. Simply grab the coil with your hand and see if it is loose enough to shift on the shock. If so, give the collar half a turn and retry. Repeat until it no longer moves, but keep in mind that coils springs should only have a few turns of preload on them. A small amount of lube between each end of the spring and the collars can also help, but be sure to wipe any extra away so as not to attract dirt.
Pivot hardware can also make quite a bit of noise, although this is one that can be intimidating for the home mechanic, requiring the removal of the pivot axles and bolts, applying grease (as well as Loc-tite if required) and retightening to the exact specs provided by the manufacturer. While I would love to cover that in this Workshop Wednesday it would make for a rather long read. If you don’t feel up to it take it to your local shop and have them perform the service. It will be money well spent.
Derailleur pulley wheels: These little guys will often make a high pitched chirp that will sound as if a bird is following you on the trail. You’ll know if they are the culprit if the intervals between the chirps are quick and happen with consistant timing while you pedal. Remove one at a time, giving it a good clean before reinstalling. Most pulleys actually use a bushing that, while designed to run dry, will benefit from a very small amount of teflon based lube. If your’s use a sealed bearing you can use a hobby knife to lift the edge of the seal up to remove it and allow you to lube the bearing. Apply a small amount of blue Loc-tite to the threads on the derailleur cage to prevent the pulley bolt from coming loose down the road, but be careful to not let it run down onto or into the pulley wheel itself.
Installing and adjusting your pedal cleats is best done well before your important ride or race. Although the process is quite simple, you should take the time to get it right. Each new pair of shoes and sometimes a new bike can alter the feel of the pedals when you are riding in earnest. Don’t skip over the heel-to-crankarm measuring step – this is the reference you’ll need to make minor changes later. Another good tip is to use your normal saddle height before you start the process, and when you are checking the fit, stand up and pedal for a spell to ensure that all bases are covered.
What You’ll need: SPD compatible cycling shoes, a sharpie marking pen, a ruler or accurate measuring device, and a set of cleats. We are using Shimano, but the same method works for nearly all types.
Step One: The first step is finding the ball of your foot.The pedal axle needs to line up with this joint to promote effective pedaling. The pen is pointing at the ball of the foot. You’ll need to find this spot when the shoe is on.
Step Two: Put on your shoes and then squeeze around the inside of the foot to locate the center of the ball of each foot.
Step Three: After you locate the ball of the foot through the shoe, mark the spot on the sole with a Sharpie pen.
Step Four: Draw a level line across the pedal using your mark. Center the cleat along the line you drew and screw it down snugly (don’t tighten it completely yet), I drew in a second line below the original – if you ride technical sections, or jump a lot, some riders like to set the cleat back 5 millimeters to add stability to the foot.
Step Five: Ride around for a bit and then stop at the 12, 3, 6, and 9-o’clock posiitions of the crank rotation. Check each position for side to side play in the cleat. If your shoe is binding to one side, make a note if it’s being forced to the right or left at each stop of the clock.
Step Six: Set the crank at the forward, 9-o’clock position, and then measure the distance from the center of the crank arm to somewhere on the heel. Use this as a reference when you adjust the angle of the cleat. Make 1/4 inch (5mm) adjustments to achieve best results.
Step Seven: After establishing the distance from the heel to the crank arm, remove the shoe and make small angular adjustments to correct any binding in the crank circle. Ride and recheck at all four positions. If all is go, tighten the cleats and ride. Remember, you’ll need to retighten the cleats after your first long day in the saddle.