Brake rotor drag question (with video)

Hey Guys/Gals,

Have a look/listen to this video, anyone have any ideas on what might be causing this dragging?

brake_drag

I was going to pull the tire off this evening but never hat the gumption to do so. It's funny how the more desperate you get to fix something the more you swallow your pride, like an addiction of sorts 8O.

Thanks for any input!

Marcel

 

When was the last time your caliper was rebuilt? I am going through this now, it's not that hard to do. I think your front wheel was spinning MUCH BETTER than mine, however.

 

I agree with Timmay... First, and I don't have a large sample of experience, but I think that is probably not a bad level of free-drag... It could be better but mine was worse than that AFTER I rebuilt my caliper and put in new lines new pads and new rotor... Now, I discovered that the EBC rotor was not centered (I doubt that is your case, but check the centeredness of the rotor)

This is the issue I had and how I fixed it (see last post) http://xjbikes.com/Forums/viewtopic/t=3 ... t=105.html

But I am guessing that your piston is just hanging up, but again, it could be worse (IMHO)... So only you can finally decide to rebuild the caliper, install new lines, new pads, etc.

 

That's not too bad, but still an issue that needs to be addressed.

Have you:
Replaced pads?
Rebuilt any part of the system?

A couple things to check:

Check the relief port in the MC, it's the smaller of the two orafices inside the reservoir. You will need a very small wire, like 2 or 3 strands from an automotive wire.

If the relief port gets blocked it prevents the caliper from moving correctly.

Also, it sounded as if the scrape wasn't all the way around the rotor. You can place the rotor on a pane of glass to check for warpage.

But my guess is the relief port.

 

tskaz,

Does this relief port wire go through something? I'm rebuilding my calipers today. Also, what do I install the new seals with to make them stick?

Thanks

 

The wire is just used to clean the port inside the MC. The hole is about a half a micron wide. It will look like there isn't a hole there, but there is.


For the seals, ONLY use brake fluid. Soak then in the fluid before installing. As long as the groove for the seal is dentally clean, it will stay put when you install the piston.

 

Actually, you better wait on the MC advice. I just noticed in your signature that it's a 750.

The OP had a 650.

The 750's remote res maybe different.

But the caliper advice is still sound.

 

Hey guys,

I rebuilt the caliber last year and changed the pads a couple of years ago. He new brakelines were installed a few weeks ago, no problems and I think that dragging was there before then as well. Seems like there is no problem with mc function...

I'm going to pull the tire tonight and have a peek, hoping there is no warping of the rotor, but I guess I can replace that if necessary. Thanks for all the input.

 

Not hard to tell it's spring, busy forum! anyways i finished hauling the tire off last night. greased up the bearings and "chamferred" the pads. I also cleaned up and the lower forks and axle, where all the bolts and nuts connect (there was some grease and grime behind the washers, etc... So far the front end has been drag free! caliper was slightly warm to the touch after rides to/from work. I'd say I'm good to go . Safe riding everyone, until next time.