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L1MEY
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Discussion Starter · #1 ·
My hubby seems to keep having the same problem with his bike... during the ride the brake pads make contact with the tyre, and he gets a nice continual braking effect. This usually happens when we've finished a fast smooth downhill section of our favourite trail. When I looked at it, it seems that the wheel is slipping in the dropouts... this has happened two or three times now. Releasing the quick release and reseating the wheel fixes the problem, but it's pretty dangerous to be riding with a bike that has a questionable connection between the fork and front wheel. The quick release is always tightened as hard as I can get it (leaves a sizeable mark on my hand when I close it).

Does anyone know the best way to fix this? If I were to use a solid nut/bolt and take the quick release off altogether, would this fix the problem? (and what size would I need?) We use a trunk mount rack, so the quick release is really only there for convenience if he gets a flat. The fork is a Suntour SF-XC60 (yeah, I know it's kinda sucky... I want to replace it, but he wants a new gun instead :rolleyes: ). He's a big guy (250lbs), and we've already had the shop jerry rig the fork with some elastomers so it doesn't bottom out every time he hits a pebble. Any suggestions that I could do at home would be great... if not, I'll take it back to the shop and see what they can do. Thanks!

- Jen.
 

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mahgnillig said:
My hubby seems to keep having the same problem with his bike... during the ride the brake pads make contact with the tyre, and he gets a nice continual braking effect. This usually happens when we've finished a fast smooth downhill section of our favourite trail. When I looked at it, it seems that the wheel is slipping in the dropouts... this has happened two or three times now. Releasing the quick release and reseating the wheel fixes the problem, but it's pretty dangerous to be riding with a bike that has a questionable connection between the fork and front wheel. The quick release is always tightened as hard as I can get it (leaves a sizeable mark on my hand when I close it).

Does anyone know the best way to fix this? If I were to use a solid nut/bolt and take the quick release off altogether, would this fix the problem? (and what size would I need?) We use a trunk mount rack, so the quick release is really only there for convenience if he gets a flat. The fork is a Suntour SF-XC60 (yeah, I know it's kinda sucky... I want to replace it, but he wants a new gun instead :rolleyes: ). He's a big guy (250lbs), and we've already had the shop jerry rig the fork with some elastomers so it doesn't bottom out every time he hits a pebble. Any suggestions that I could do at home would be great... if not, I'll take it back to the shop and see what they can do. Thanks!

- Jen.
Check to make sure that there is no damage on the fork dropouts. Even with a guy that weighs 250, the wheel should not slip in the dropouts. This is usually caused by poorly made / incorrectly used quick releases.

Get a good QR like Shimano XT or Hope or Salsa. Make sure that the cam is clean and greased. A dirty cam will feel like it's locking tight, but can cause the symptoms that you describe.
 

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This may sound like a dumb question, but how do you tighten the lever? Do you screw it down until it's tight or flip the lever "closed"? Some people use the former method and it doesn't work.

Granted that you're clamping the QR lever correctly, you may also check to make sure that neither end of the axle reaches past the outer edge of either fork end. If one end sticks out past the fork end, it needs to be adjusted and centered. If both ends of the axle stick out past the fork ends, then either the axle is too long, the fork ends are worn down or they're damaged.
 

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You are correct this is a serious problem I would recomend that you resolve the cause or take it to a competent LBS before riding it again.

I can think of a couple reasons this could be happening.
One; the quick release is bottoming onto the axle. There are a couple things that will cause that, the fork dropouts could be too thin, they could be worn or just out of spec originally. Second the axle ends could be too long this is caused by an axle that is too long or by hub races that are too close together (forcing the axle nuts further down to compensate) This condition can be made worse by a quick release that has little (or no) cupping on the clamping surfaces, allowing the axle to contact the ends. It could be a combination of some or all of the above where each item is ok but on the far end of it's tolerance, when they are used together the tolerances accumulate so they don't function (clamp the wheel)

Two; your quick release could be malfunctiong, it could be dirty corroded or just defective, and not providing adequate clamping force even though you are using a high force to close the skewer.

If you are diagnosing this yourself try swapping out components (wheel, skewer, fork) to isolate the out of tolerance or faulty item.

It is worth mentioning that there is a popular belief that the the knurling on the skewer ends provides some of the grip for holding in the wheel. This is FALSE the axle ends on the hub provides ALL of the retention for the wheel the skewer merely provides the clamping force. The skewer rod is not held tightly in the axle so if your wheel is actually moving enough to stress (put pressure on) the skewer you are already in serious trouble, the knurling on the skewer ends is only there as a fail-safe only, not as a means of primary retention. Many many hubs use aluminum axles without proper knurling (steel or titanum insert) on the axle ends (aluminum knurling cannot properly grip a steel or titanum frame and might even have trouble in some types of aluminum)

I am serious about NOT RIDING THE BIKE untill you diagnose (or have a dealer diagnose) the problem. You (or your spouse in this case) could be seriously injured of the wheel was to fully seperate while riding.
 

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Don't touch me!
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2 possible explanations.

The first is of course operator error. I am assuming you know what you are doing, so on to #2.

The second one is the actual skewers themselves. I bought a set of Kore skewers at PP a few years ago, and they would always spin in the dropouts after a ride. Turns out the handle would have it's highest tension at about 3/4 of the way closed. When fully closed, it would lose some of it's tension. I realized how badly the design was implemented after looking at the locking motion. They have since been relegated to paperweight status.

No offense to your hubby's skewers, but if the bike was spec'd with a low end fork, I'd expect the skewers to be of questionable quality as well.
 

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L1MEY
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Discussion Starter · #6 ·
Thanks for all your replies :)

I took a look at the fork and QR, and it all seemed clean and tidy. We took the bike to our LBS for them to check out since this isn't a problem I'm familiar with. They couldn't find anything wrong with it either (they measured the fork and checked out the QR). I guess it could just be a cheapo QR that slips after a bit of abuse because it only happens after we do a long steady downhill run at about 20mph. I'll swap it out with my front QR which doesn't slip for me (I'm half the weight though), and see if that makes a difference.

- Jen.
 

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Salsa QRs

My rear wheel would slip and screw up the chain line and cause a lot of drag when I pedaled. I have recently purchased Salsa QRs. Somewhat pricey at $40.00 a pair but they seem to work well and so far no problem. I figure if the QRs hold your wheels to your bike, this may not be something that you really want to skimp on too much.
 

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forget QRs, convert to a 9mm solid axle (front) or a 10mm solid axle (rear) and use axle nuts. These are MUCH more secure than QRs, and they solve wheel-slipping problems
 

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Fo' Bidniz in da haus
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Jm. is right.....although I have had this problem with a bike in the past and a new set of QR skewers solved the problem, I only weight 180 pounds....at 250#s, Jm. is spot-on with the advice....
 
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