Rear quick release loosens.
 

I have a weird problem which I have never seen before. I have titanium frame mtb. I use it mostly riding in the streets when I just want to noodle around, ride to work and such. I broke my collar bone in a road cycling accident about 8 years ago and figured it was a more forgiving way to get me riding again without worrying about my skinny road tires falling into another crack.

I have noticed that sometimes when I ride the bike hard, the rear quick release skewer has loosened. I'll go to put the bike up on the bike rack and the rear wheel will just fall off. Kind of unnerving and likely dangerous.

The cam is still locked in the closed position and I seriously doubt the skewer is stretching. My only guess is that the nut is 'walking' loose because of pedaling forces. I'm not that strong of a rider (about 175lbs. If that helps). Is it likely that this titanium frame flexes enough under pedal load to unscrew the skewer nut? The quick release skewer is a Vuelta. The frame is a Motobecane Fantom Pro, about 2010 vintage. A better quality skewer might solve the problem, but I am curious if anyone has a clue to the cause. Thanks

Joe R

I have had a QR loosen on me, but I started tightening them a bit more and have had no further issues.. Are you confident it is tight enough to begin with. I usually tighten them so the ever leaves a bit of an impression in the skin on my hand as I push it closed.

maybe there's something wrong with the skewer

But yeah, like bikeaddiction, i go tight as i can

Are the axle nuts spacing correct to the dropouts?

Remember Liquid Paper? A.K.A. "WhiteOut"? Find an old bottle that hasn't dried up yet. Then mark a line between the nut and dropout, and ride 'til it loosens again. That might shed some light on how easily / how much it loosens.

You're taking note of the lever position when you re-tighten it, and the lever does not change position; right?

What material are the dropouts? Are the inside surfaces of the cam and nut "knurled", and do you see them marking / digging into the dropouts? Same question wrt. the outside surfaces of the locknuts.

These May be less prone to come loose than your typical external cam light weight Skewers..

https://www.dtswiss.com/en/products/hubs-rws/rws/5-mm/

https://dycteyr72g97f.cloudfront.net...EB_SHO_901.jpg

Please don't feel insulted if this isn't you. LOTS of people use quick releases incorrectly. It's not a wing nut.

1. Hold the lever parallel to the axle land tighten the nut on the opposite end until it is finger tight.
2. Now push the lever in so it is perpendicular to the axle. If it's not hard to do, you didn't do it right.

The OP mentioned "The cam is still locked in the closed position", so I have to assume that it is actually being locked. Partly tighten down the skewer with the cam open, then flip the cam to lock in place.

I like and trust the "vintage" internal cam skewers. They work very well. Steel or Stainless skewers?

Some nuts are knurled, some are not. I'm not sure it really makes that much difference. The knurled nuts will leave marks on your frame, but won't loosen (without stripped teeth as [MENTION=3949]Davet[/MENTION] suggested).

I've ridden bikes with horizontal dropouts for eons. Stand up and pedal, and the wheel will slip if it isn't tight. So, I've gotten a lot of practice getting my skewers almost as tight as I can get them without tools (cheaters).

A few comments.

Frame- Some Ti frames use 64 Ti for the drop outs (being plates and not having the manipulation that making a tube goes through). This alloy is very hard and there have been many reports of axle coming loose in this kind of drop out material.

QR- I would strongly suggest you use only steel capped QR skewers with an internal cam design. Not only do these QRs have greater gripping ability then a QR with Al end caps the over center cam action can apply greater clamping forces then a wing nutted design. (Like the "fancy" DT's photoed, which are basically just very expensive wing nuts. To their credit, at least, they do use steel gripping surfaces)

QR- I also suggest a steel (not Ti) skewer shaft as Ti has greater stretch then steel has.

QR- lastly make sure that a conical QR end spring isn't installed wrong. All kinds of securement issues happen when the big end of the spring is sandwiched between the axle, the QR end cap and the drop out. This is far easier to do then those who do it want to admit:) Andy

Is your axle too long? If so, the QR will be clamping down on the axle instead or the dropout. The axle only needs to stick into the dropout enough to serve as a useful guide. It shouldn't even reach the outside of the dropout. (It actually does not even need to reach the inside of the dropout. The clamping force of a good skewer is plenty. (The post above just memtioned this. A quick jury rig - add thin washers behind the locknuts on the offending side(s).)

I'll second Andrew on wanting a quality all steel quick-release, especially the skewer. You are throwing away a lot of clamping force with titanium. Aluminum here is less than useless.

Ben

I will ditto Andy's and Ben's advice: check that the skewer is biting into the dropout with all its available clamping force. A quick way to do this is to remove the conical (aka volute) springs from the ends of the skewer. They're only there to make it easier to reinsert the wheel- you can do without them for a few test rides.

And I third the recommendation for a quality all-steel skewer. I only use Shimano skewers on my bikes, except where the hubs are Campagnolo.

For horizontal (or near horizontal) dropouts, the Campy-style skewers are very secure, provided the axle does not extend past the dropout face.

For vertical dropouts, the axle still must not extend past the dropout face, but the demands on the skewer are less. Since the wheel can't go forwards or backwards in this type of dropout, the skewer only needs to hold the wheel from falling out.

The OP doesn't say what type of dropouts his frame has, but I would guess that most MTBs have vertical dropouts.

My guess is that the axle is extending beyond the face of the dropout, and that will prevent any skewer from tightening properly.

This is one more thread that will benefit from the OP replying after they find out what's going on. Andy

QL loosening
 

Hi guys, sorry for the slow follow up. Appreciate all the input.

A few pieces of info based on some of the comments: the skewer is steel, not aluminum or titanium (the frame is ti), the nut is aluminum but it is not stripped, both the nut and the cam side are toothed, the axle does not extend beyond the dropouts, it is probably about 2 - 3mm shy of the outside of the dropouts on each side.

I had thought about the 'whiteout' idea (or something similar) to check movement of either the nut or the cam side. I am curious about what that will show and will report back.

A lot of folks suggested that I make it tighter, and I certainly will give that another try. It's just that I've been riding on wheels with Q/R since about 1975 and have never seen anything like this before.

It may be simply solved with a better quality Q/R. But I remain curious as to what the heck is going on here!

More info more better but... We still don't know the cam design. Is it an exposed design that rotates on a plastic "washer"? Or an all metal internal cam, within a cap?

Since getting the best QR for tightening aspects is so easy I don't see why this isn't done. Andy

This is my thought too.

Put a different skewer and nut on and see if it still does it. I had a bike a long time ago do this from time to time and I replaced the skewer and the problem went away.

Shimano internal or that DT one that the lever is made to be like a wrench in 6 ,

not the one like in 11.. not enough clamping force..