You are hereForums / By Discipline / Mountain (off road) / MTB Gear / Front Wheel, Spokes Hitting Brake Calipers

Front Wheel, Spokes Hitting Brake Calipers


Geoff1963's picture

By Geoff1963 - Posted on 02 January 2009

NB: Originally posted elsewhere on the Global Riders Network and appears via syndication.

The spokes on my front wheel are rubbing against the brake caliper when I peddle under pressure, up hill, accelerating from a standing start etc, any suggestions as to why this would occur. I ride a 2008 Epic Compo.

Cheers

Geoff

Tags
alchemist's picture

Possibly your wheel needs tensioning. Stand over the bike and grab the top of the front wheel - can you flex this from side to side?

Geoff1963's picture

There is a bit of play there, not much, however, when I'm peddling hard and leaning forward it would increase, so tighten the spokes I guess?

delicious's picture

This comment has been moved here.

Whisperer's picture

After 30+ years of wheelbuilding, I still got a lot from this book by Roger Musson:
http://www.wheelpro.co.uk/wheelbuilding/book.php
This guy is a legend in the UK.

It's available as a pdf download for $14 USD, and that covers you for future updates.
The current version covers UST rims which is handy.

My basic tips: Keep those spokes tight, but be careful to ensure they are EVENLY tensioned. Even tension is more important than a slight amount of runout on MTB bikes.
If you are not sure how tight they should be, do the fingernail 'ting' test on spokes on a few bikes when you are out with the gang, or in a bike shop.
W

Nic's picture

... on a wheelset I built myself. Turned out I had laced the spokes a bit wrong - under instead of over. Figured this out on a ride and just pushed the offending spokes in a bit.

Never had the problem again - and never got around to fixing the lacing.

Cheers

Nic

ps The wheelbuilding book is well worthwhile - I got an email to say there was a (free) update, just a month or two ago.

Morgan's picture

If you're still around mate apologies for my heathen associates - I hate it when people go off topic too......

Anyhow - re your problem..

First - are you sure it's your brake caliper the spokes are touching? Have you got a bike computer? Check the fork and spoke mounted sensors aren't too close together - less than a couple of mm's and even a minimal amount of flex will have them touching.

Second, check your quick release skewer is tight and tighten it if it isn't. That probably wasn't the problem but eliminate the easy stuff first.

Third - check your brake caliper. Is it too close to the spokes? If something is only a couple of mm's from the spokes (and it might be washers sticking out past the body of the caliper) it's probably going to touch with minimal wheel flex. Check your brake pads are equally distant from the disc. If the outside pad is rubbing the disc your caliper is going to be closer to your wheel; centring the pads will move the caliper away from the wheel in this case. If it's washers sticking out, make sure you push them away from the spokes when you tighten your brake caliper bolts so they don't stick out past the caliper body.

Four - it's either a hub or spoke problem. To check which, steady the bike, grab the top of your wheel and move it from side to side, giving it some decent effort. If it's a hub issue the wheel itself will feel solid but it will move and you'll "feel" a 'knock' and might hear a faint noise. You just need to tighten the hub.

If it's spokes the wheel will feel mushy and it will move 'around' a solid feeling hub. You can also flex the spokes by squeezing pairs of spokes on the same side together. If any of them squeeze together more than a mm or 2 they're too loose. Unless you know how to fix this I'd suggest playing safe and getting the bike shop to do it. If you haven't been seriously jumping/crashing the bike then I'd get them to re-lace the wheel because well built wheels don't get that flexy through general riding.

One more thing - the last and worst case scenario is your fork. But you'll be at the bike shop by now and they'll check that out for you.

Hope that helps..

Gilbo's picture

top work guys, great to see the spirit of NOBMOB and the willingness of all to help a fellow rider with a question has been answered with not one, but many suggestions.
Unlike the ONE twit, who has seen it fit to defame someone because they splet a wrod worng.
NUMNUT.
I only hope this doesnt alienate any other newcomers from joining a great communtity brought together by the love of MTB'ing.
cheers,

Alex's picture

aww my one was good bring it back? Smiling ill play nice i promise

Stuart M's picture

and I hadn't evan possted anythang in this tread yet

Let there be light

delicious's picture

About your wheel. As others have pointed out, get your wheel trued which will cause the spokes to straighten and move into the correct position. This sometimes happens with OEM machine built wheels. They all loosen together and the wheel doesn't appear buckled, yet it's weakened and it's only when the spokes touch the brake caliper does it get noticed. It may be best to get the wheel rebuilt using the existing hub and rim with new spokes. At a bike shop, the staff would discuss with you your riding style and thus suggest the correct spoke and build.
How do I know all this? I work at a Specialized dealership. I'm no pro wheel builder yet I spend a good part of my time truing wheels and diagnosing problems like these.
Also, your brake caliper may require an alignment.
I should have offered this advice from the start and not an English language lesson and for that I apologise once more. So take care, best of luck with your Epic and do get involved with NobMob. Not everyone here is a closet English teacher.
And as for you Alex. Would you like to be shown around Menai, now that I have Monday and Tuesday free? I promise, no English lessons and I won't criticise your breaks, I mean brakes.

Hans's picture

And right back to the topic... Eye-wink

Wheel truing and spoke tensioning

Our friends over at Bikeradar have some excellent instructional workshop guides and videos for various MTB maintenance tasks.

See : http://www.bikeradar.com/gear/article/workshop-t...

Workshop guides: http://www.bikeradar.com/gear/workshops

Alternatively you can give Adrian at http://www.belrosebicycles.com a call and he can do it for you for reasonable $$'s.

He fixed mine and my son's buckled rim on the spot, has the right tools & spares and most importantly experience. Eye-wink

Hope this helps.

Rgds, Hans
__________________
May all your lines be the right ones...

Alex's picture

lol yeh man you can criticizzze my rear brake all you want, it has not yet been avid coded like the front (god i love that code!)
yeh ill hit a trail or 2 with you, all's fair in love and bicycles Eye-wink tee it up!

Comment viewing options

Select your preferred way to display the comments and click "Save settings" to activate your changes.
Best Mountain Bike