"Actually you are the first person to bring up this issue"

25 March 2004

 

Recently, a rider who had experienced a problem with his front wheel contacted me. He had found that he could not stop his wheel from being pulled down in the dropouts under firm (disk) braking. He sent an email to the relevant manufacturers to see what they suggested (all the quotations are edited down to the relevant sections and to conceal personal information). Read on and see how they responded.



His original message:

"Under sudden heavy braking the front wheel is moving in the dropouts.  Seems that the downward forces of the disc brake are pulling the disc side of the wheel toward the opening of the dropout causing the disc side of the King ISO disc hub to slide down the dropout.  Three times now in my first ten rides on this bike I have found that after heavy braking or a sudden hard stop, the front brake begins rubbing because the wheel has moved and become misaligned.  When I release the QR and then re-tighten, the brake is perfectly aligned again."

Chris King's response:

"Actually you are the first person to bring up this issue."

Avid's response:

"This has not been a problem at all - I've never had such a complaint. A normal dropout should, and is designed to, have sufficient tension to keep this from happening. You most certainly have a big problem with your fork dropouts and/or the QR.  I'd get this fork/QR issue handled before you ride any further."

Manitou, the fork manufacturer concerned, did not reply to his email. But he spoke to both Fox Racing and Manitou on the phone.

First Fox:

"I explained the problem I was having and was told that lots of people ride the trails in Santa Cruz (Fox headquarters) with discs and QR's and never have any problems.  Twice it was suggested that I try better QR's."

And then Answer/Manitou:

"I explained the problem I was having with the wheel moving in the dropouts after heavy braking and the immediate (almost too immediate) response was that I was the first person to report this issue. [...] In the end, the tech rep I spoke with was very informed and helpful but it was clear that his message was that I had presented him with a unique case"

So there we have it. One year on, and the manufacturers are all still claiming that they have never heard of any riders experiencing any problems whatsoever with their products. At least Avid realise that this is a serious problem (you most certainly have a big problem with your fork dropouts and/or the QR.  I'd get this fork/QR issue handled before you ride any further), but the fork manufacturers don't seem at all interested.

Another correspondent alerted me to this thread on singletrackworld:

"Hmm..., here's a thought (and almost certain to open old discussions) over the last few weeks a number of QR's have come loose when using Fox Forks, just last weekend there was at least 3 occasions of this happening and its happened to me on a number of times."

and this review of the Marin Mount Vision (featuring Fox forks) appeared in the April 2004 issue of MBR:

"There has, of course, been the odd problem. Following a ride round the Roc d'Azur race course a few months ago, I was suffering a terrible 'loose headset' feeling and stopped sharpish to investigate. The headset was fine, but the QR had become spontaneously loosened. I shrugged it off, but this wasn't the last time the QR fairy visited. Three or four loosening later I finally got the hump and changed QRs for a brand new set of the production models, just in case I had a faulty batch. That was a few weeks ago now, and it has happened twice since. Not good."

MBR's Editor, John Kitchiner, told me I couldn't quote that because it is copyright. I believe that my use is entirely fair and have yet to receive any writs!

On top of that, Lennard Zinn's article has similar comments:

"I have noticed on my own mountain bikes, all of which have disc brakes, that if I use a skewer where the lever is aluminum with an off-center hole at its rounded end to create the cam, I get downward movement of the axle in the dropout."

It is astonishing that Fox can remain ignorant of all these problems. In fact, it seems barely credible. On the other hand, it appears that the vast majority of riders who experience problems such as a slipping hub or loosening skewer do not bother to inform them (or any other manufacturers) of the problem. While the industry is still pretending to not know anything about the problem, it seems determined to not deal with it.



You can send us an email here. I'd be especially grateful for any more comments from manufacturers or from anyone who has contacted them with a similar problem.
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