front brake help

rwgoldsmith

rwgoldsmith

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hey guys i had this in the garage help section but havent been getting alot of help i think this part of the forum gets more looks so i thought i would post here
on my 01 i replaced the master cyl with a 01 r1 unit and venhill braided lines when i went on a test ride after about a mile i had my brakes suddenly lock up with absolutly no warning.
i have been trying to figure this out with your guyses help
some have said there is supposed to be some brake drag so in this vid i made is this too much brake drag or is that how it is supposed to be?
RW
is this right? - YouTube
thank you so much
 
I saw that earlier and wanted to say that although mild rubbing is normal that seems excessive. It really seems the pistons are pushing out to far. That is exactly what would cause everything to heat up and lock up.


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thank you missy that was the big thing i wanted to know
i am going to put on the old m/c to rule the new one out as the cause
the pads still have a tonne of meat on them so what else would cause the pistons to come out too far?
thanks again
RW
 
Can you try to lift off one caliper at a time to see if it is only one dragging or both? If it is only one, then that might rule out the MC. If the MC was keeping pressure, it would be on both at the same time.

*EDIT* I see you did have trouble with one of the calipers. Yes, I'd rebuild them both. Clean them out with brake cleaner then take care of any surface imperfections with a fine emery cloth or 0000 steel wool then clean thoroughly again with brake cleaner. Reassemble with new kits and they should work very easily with your hands.
 
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That's definitely "hanging up" on the calipers! Way too excessive. I may have one or two rebuild kits in the garage from when I was going to do my 01' calipers but wound up getting GenII calipers for a great price and swapped them out. Let me look tomorrow for you before you go buying kits. If I have the parts I'll send them to you in a regular envelope. They are only a set of O-rings and stuff.
 
you could try some brake cleaner on the caliper pistons, spray it on then lever the pads in an out,do this several times spraying every time,check after to see if it free`s up the wheel,maybe worth a try
 
well i got the bits ordered for my brakes plus i'm going to rebuild the master cyl while i am at it.
also ordered the t rex frame sliders so my credit card is on fire.
btw if your doing the calipers you need one of these refrence numbers #5, 7, 15, 17
i'm sure you could do just 2 of 5 and 7 but thats what the guy at partshark said
thanks for the help guys rw
 
rwgoldsmith said:
well i got the bits ordered for my brakes plus i'm going to rebuild the master cyl while i am at it.
also ordered the t rex frame sliders so my credit card is on fire.
btw if your doing the calipers you need one of these refrence numbers #5, 7, 15, 17
i'm sure you could do just 2 of 5 and 7 but thats what the guy at partshark said
thanks for the help guys rw
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Glad to hear that you are getting the parts. Let us know how it goes when you do the rebuild.:tup:
 
After you replaced the M/C did you notice if the fluid was returning to the master cylinder after the brake lever was released? Many times the problem is not with the M/C but the wheel calipers. You should try to depress the pads with a "C" clap or something of that nature to make sure the pads will "retreat" after the lever is released. If it they won't, you'll have a constant pressure on the rotors. If you didn't touch the calipers then that's probably not the issue but at the least you must have bled the lines and at that time you should have had zero pressure on the brake pistons. Just check everything out so you understand what's happening andnot replacing parts that don't need to be replaced. Some Yamahas in the past have had the "purge" holes plug up from moisture forming crud in them which keeps the fluid from easing back to the M/C after the brakes are applied.
 
Lonerider59 said:
After you replaced the M/C did you notice if the fluid was returning to the master cylinder after the brake lever was released? Many times the problem is not with the M/C but the wheel calipers. You should try to depress the pads with a "C" clap or something of that nature to make sure the pads will "retreat" after the lever is released. If it they won't, you'll have a constant pressure on the rotors. If you didn't touch the calipers then that's probably not the issue but at the least you must have bled the lines and at that time you should have had zero pressure on the brake pistons. Just check everything out so you understand what's happening andnot replacing parts that don't need to be replaced. Some Yamahas in the past have had the "purge" holes plug up from moisture forming crud in them which keeps the fluid from easing back to the M/C after the brakes are applied.
Click to expand...


i put the old master cylinder back on just to prove that it wasnt the new masters fault, i'm now just rebuilding everything for peace of mind and a rebuild kit for the m/c is only another 20 bucks.
RW
 
alright finally got the parts from part shark it only took them a week and a half. boo
but the guy was helpful when i called him.
time to pull everything apart again :)
 
rwgoldsmith said:
alright finally got the parts from part shark it only took them a week and a half. boo
but the guy was helpful when i called him.
time to pull everything apart again :)
Click to expand...

I always cut them some slack on the shipping times because they more than make up for it with their prices and customer service. Amir is the best! I'm glad your all set though. If you can please take some shots of the process cause that would be a great help to all of us that haven't done ours yet.
 
crap
sorry forgot to take pixs, though it was simple enough to do.
the hardest part was getting the pistons out. i used an air compressor which worked pretty well. then the seals came out with a dental pick and new ones snap back in
if i can sort it anyone can do it.
i got them rebuilt now i'm dicking around with my m/c cant get that snap ring out for the life of me. hopefully ill be going within the week.
 
rwgoldsmith said:
crap
sorry forgot to take pixs, though it was simple enough to do.
the hardest part was getting the pistons out. i used an air compressor which worked pretty well. then the seals came out with a dental pick and new ones snap back in
if i can sort it anyone can do it.
i got them rebuilt now i'm dicking around with my m/c cant get that snap ring out for the life of me. hopefully ill be going within the week.
Click to expand...

Great news bud! I knew you'd be able to tackle that job no problem!
 
well i think its time to get it to the shop. i have now rebuilt everything and i'm still overheating and locking my front brakes but i got twice as far this time. also my chain ate a small coolant hose so i spent the morning replacing that. the brakes dont seem to be dragging anymore so idk what it could possibly be. i even adjusted my lever back to be sure i wasnt riding it. ugg
 
just the brakes the shop is about a mile from my house and there was that nice burning brake pad smell when i got there. the coolant line was just me putting that front sproket cover on wrong:)
 
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