Disc rubbing after removing front wheel

[parabola]

Technical question for you guys

 

Im having trouble with my front disc brake, an avid juicy 5, being used with a shimano RM65 hub with a 180mm XTR rotor. The wheel skewers are the stock shimano ones.

 

I find that I can get the brake calipers perfectly aligned, but as soon as I remove the front wheel, I need to readjust the caliper, and/or play with the quick-release for about 10 often futile minutes. I have found that the problem lies with the inner locating nut of the wheel skewer, the part that locates the inner edge of the shaft with the inner face of the fork. The nut is not round, and has flat edges so you can use a spanner to clamp onto it. if I orient the nut differently, the disc position changes significantly when I clamp down.

 

so my question is

- would buying new skewers help, or is there another cause of this that I can fix myself?

 

 

[Wyatt Earp]

Parabola

 

There could be many answers to your question, let's start with the obvious.

The caliper might not have been set up properly to start off with.

Take the wheel out, get a flat clean screwdriver or a thinnish tire lever, now push the pistons back into the caliper.

Make sure the brake caliper is floating, in other words loosen the two allen bolts that bolt the caliper to the adaptor.

On the Avid brakes make sure that all the little washers are nice and loose.

Put the wheel back in the fork and make sure that the dropouts are sitting flush on the hub axle on both sides.

Tighten your skewer.

Now spin the wheel and pull the brake lever, hold the lever in the braking position.

Tighten the two caliper bolts and spin the wheel again, see if it's drag free, if not then loosen the caliper bolts just a tad and align the caliper over the rotor by eye and with a flashlight untill you see the rotor in the centre of the pads.

Check also that your rotor is true,

This should solve your problem, just make sure that everytime you re-install the wheel that the axle is flush with the dropouts.

If your problem still persists it could be something else.

One thing to check out of interest, when you tighten your skewer , how much do the fork lowers flex ?

Summit Cycles2008-10-09 11:01:20

[Tumbleweed]

snippity' date=' snip

Put the wheel back in the fork and make sure that the dropouts are sitting flush on the hub axle on both sides.

snippity, snip

 

[/quote']

 

 

 

i always find that using the weight of the bike - ie, "dropping" the forks onto the axles - rather than putting the wheel back with the bike upside down, always gets my rotor to go where it should. may sound silly and unscientific, but it works.

[Wyatt Earp]

snippity' date=' snip

Put the wheel back in the fork and make sure that the dropouts are sitting flush on the hub axle on both sides.

snippity, snip

[/quote']

i always find that using the weight of the bike - ie, "dropping" the forks onto the axles - rather than putting the wheel back with the bike upside down, always gets my rotor to go where it should. may sound silly and unscientific, but it works.

 

[parabola]

I have followed your method to the T previously and have had to repeat it everytime I put the wheel back on I have had them adjusted by a professional only to come home and put the wheel on, and same problem. will try the force method though and see if that helps., it is definetly related to the position of the shaft with regards to the dropout flanges.

 

When you say "just make sure that everytime you re-install the wheel that the axle is flush with the dropouts." can you explain a bit further please

 

Thanks for the responses, much appreciated

 

[Wyatt Earp]

Basically make sure that the roundings in the dropouts are touching the axle on both sides, where you set the caliper the firts time is where the wheel should be positioned all the time so doing it flush with the axles that way you will know that the wheel is not sitting skew but that the rotor is always in the centre of your pads.

If there is alot of movement in the fork legs when you tighten the skewer then the axle spacing could be wrong, what hub is it ?

Edit:

Sorry I forgot, also don't pull the brake lever when the wheel is out, this will push your pistons out and the spacing between the pads will get smaller.

Put a spacer in between the pads when you transport the bike

Summit Cycles2008-10-09 12:17:56

[Jules]

snippity' date=' snip

Put the wheel back in the fork and make sure that the dropouts are sitting flush on the hub axle on both sides.

snippity, snip

 

[/quote']

 

 

 

i always find that using the weight of the bike - ie, "dropping" the forks onto the axles - rather than putting the wheel back with the bike upside down, always gets my rotor to go where it should. may sound silly and unscientific, but it works.

 

 

 

This is the most important thing any new rider can learn. Particularly one who takes his or her wheels off regularly. I actually taught Bored Girl the same trick today.

 

 

 

So many times the solution to a brake problem lies in just opening the skewer, weighting the wheel, and closing it again.

 

 

 

That said, I'm sure Parabola is aware of this trick. How about turning the axel/skewer into a familiar position each time you put the wheel in - that might help?

[Tumbleweed]

another snippety snip That said' date=' I'm sure Parabola is aware of this trick. How about turning the axel/skewer into a familiar position each time you put the wheel in - that might help? [/quote']

 

 

 

 

 

sorry to sound all zen-ish about this, but you really do develop a sense of the exact hand-torgue to getting this right... ok, maybe i should go to bed now... night-night, my friends!holy roller2008-10-09 13:29:17

[parabola]

Thanks for all the help guys..

Parabola

One thing to check out of interest' date=' when you tighten your skewer , how much do the fork lowers flex ?

[/quote']

I think I may have found the problem. The caliper moves significantly when I clamp the skewer down, due to flex in the fork. The fork is an RST Gila 4, standard on the bike. Would upgrading the fork solve this, and do you guys have any suggestions as to what to upgrade to?

 

The bike is an 18" Merida SUB60 hardtail bike, currently with an 80mm fork, but I would like to upgrade it to an air sprung 85-100mm lightweight XC fork, as I use the bike for mainly singletracks and trail riding. I am looking to spend R1800-R2500. I have been looking at the RS Reba/Recon and the Marzocchi MX comp.

 

[Speed Devil]

Parabola

 

Put the wheel in and make sure the fork is flush on the axle. Then pull the brake while tightening the skewer so that the wheel stays centralised while tightening.

[turtlek]

everything abotu the brakes has been covered so i am going to touch on the fork that fork is very soft and variations do happen i had the same problem with my RS Tora but have sorted it out since sorting out the spacing on the axle (very long story) but in short changed wheels

 

 

 

effectively upgradign shocks will help you with that but it is a very expensive idea and might not be what you need but in all honesty if you looking to go for a decent fork the RS reba series is never a bad buy for reliability and price

[Wyatt Earp]

sorting out the spacing on the axle

 

That is why I asked how much the lowers move.

Good advice here turtlek, spacing the axle will surely help a stack.

 

The Reba is not just a good buy, it's a great buy.

+ and - air chambers and motion control on the damper side which also offers you a rebound function.

32 mm Stanchions are strong enough to hold up most body weights and can easily be converted from an 80mm shock to a 100mm and ultimately a 115 mm. if the geometry of the bike allows for that sort of travel.

[parabola]

 

Ok so heres the situation.

Took the bike to the bike shop, adjusted the wheel spacing, new front fork, RS Recon Race 08.

Attach the wheel following these instructions to a T and finding that the discs are in a different position relative to the caliper and rub lightly, meaning I have to readjust everytime. Could it be the rotors? I had them tightened at the lbs. Will do some more experimentation and see if I can isolate the problem.

 

parabola2008-11-01 16:04:35