Why do my wheels keep slipping?

This age old question is something which comes into our emails at least once a month, and often I end up writing a long-winded ramble about how it's a symptom of many issues. If we had a dollar for the number of times we got this question, we would have many dollars.

How it should look, brand new dropouts paired to some brand new nuts.

A wheel pull is typically the type of thing that occurs on a standing start or during a high torque acceleration. The drive-side nut/axle end slide forward, causing the wheel to make contact on the non-drive chainstay. In extreme cases, this causes heavy damage to the frame and in the absolute worst scenarios, the wheel & tyre too. Everyone loves to blame bad frame or wheel design, but it's often not the case. Improper maintenance is typically the cause, and as your components and frame age, the issue begins to compound rapidly.

Why does this only happen under load?

When the system sees movement under load, and loses clamping friction, the wheel will natively move. Imagine your drivetrain as the following, when you pedal forward on your bike, you're essentially causing the frame to compress on the drive-side, the compressive force on this side of the frame is counter-acted with expansion forces on the opposing side (side quest: this is why many bikes have bigger non-drive chainstays) of the frame. As the axle deforms and bends under load, the clamp force on the nuts and axle supports becomes uneven and is prone to slipping. From here everything goes south.

So how do we diagnose & fix it?

Let's start with dropouts
Remove your chain and set it to the side, attempt to install a wheel and slide it forwards in the dropout. If the wheel jams or feels tight, it's time to get your #3 (finishing) file, and give the dropouts a light clean up. Typically I focus on the spots which are tight, and clean the edges up with a light chamfer to reduce the risk of it happening again. A key note, dropouts are a consumable item and as such many track frame manufacturers sell replacement dropouts.

Tim is filing dropouts mid-event, to ensure no accidents occur during racing.

Onto your wheels
Remove your nuts, and inspect the axle supports - these are the part which make contact with your frame on the inside of the dropout. If you notice compression marks, deformation or even signs of the knurled interface being crushed, it's time to replace them.

Now. it's time to clean up your axles
Next we want to clean your axle threads and nuts with some isopropyl alcohol and a brush. Once it's dry, try winding your nuts back onto your wheel. If they lock up at any point, the threads on your axle or nuts is damaged and need repair or replacement. If there is no fault, it's time to look further here... If you notice your track nuts show signs of "mushrooming" or the knurled interface (if present) are crushed, it's bin time! Track nuts require lubrication, we recommend sewing machine oil on the axle and under the washer on the nuts. Without this they are more prone to binding and cause axle creep when installing in your frame.

Four low-end nuts showing varying signs of their life cycle.
Left - No damage to the knurling, Middle Left - Mushroomed head and incorrect wrench used previously, Middle Right - No Visible damage however the thread was damaged, Right - Crushed washer/knurling, time for the bin.

Mushrooming is when the nut begins to deform over the top of the washer, and once this occurs, the nut will often bind on the washer, causing improper lockup, and often twisting the axle when you're tightening your wheel. Damaged nuts are often overlooked and are the most common issue we find.

Runwell's nuts feature a chamfer on the back of the nut where it contacts the washer (gold part) reducing the possibility of mushrooming, and helping keep correct engagement with your frame.

I've done all that and it's still an issue?

I hate to tell you - but you're missing something. More than likely your axle thread and nuts are damaged, and despite passing a visual inspection it might be time to consider replacement or repair of both. When wheel nuts are over-torqued even once, this can cause the threads to stretch and once that occurs you will always have issue present.

What products does GEAR Shop Brisbane recommend?

For dropouts and your axle, you're locked into the manufacturers material and standard. As an example, a Mavic Track wheel or hub will need a Mavic axle and supports. A DT Swiss hub will need a DT Swiss axles and washers, and so forth. Track nuts leave more room for improvement and colour choice. Our all time favourite is the Runwell Elite Track Hub Nuts (as they offer solutions for metric hubs, as well as Campagnolo's proprietary thread), followed closely by DT Swiss and Shimano (which bare a striking resemblance to one-another).

How it should look, undamaged dropout, brand new nuts, no issues at all!

Anything else to consider?

If you want to attempt a repair yourself, you'll need a few bits. Most track wheels us M10 x 1.0mm threads. If you can source a high quality HSS Tap and Die to suit, you should be able to re-cut and clean your threads yourself. For Campagnolo, you're limited to replacement, or if you're local to us, we had custom taps and dies manufactured for this, if you want some for yourself, reach out to us. If you've done everything here and still have issues, the only UCI legal option you have is to purchase some Velobike Axle Locks. These were developed for use with the QAS after riders kept pulling wheels, despite everything being perfect. Pair these with some Runwell Elite Track Hub Nuts and you're likely set!

What's best practice moving forwards?

A few things should be considered.

1. Lubricate your threads and Track Nuts regularly. You don't need a lot, a drop is often enough
2. Keep an eye on your dropouts, if they're beginning to mushroom again, clean them up right away
3. Torque your nuts up. 30-35nm is more than enough. If you're not sure, buy yourself a torque wrench and a 15mm socket. Just don't undo the nuts with a Torque wrench or you'll damage your fancy tool

Some Avanti dropouts that have had a previous clean-up, notice the clean chamfer on the edges?

I can't find the replacement parts?

No problems there. Drop us a photo of your setup, along with the models of wheels / hubs and we can help source them for you. If we can't get them, we will likely be able to guide you where you can get them.