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My sv650a k5 master cylender had to be changed due to demage.
By an advise from a motorcycle shop i bought my self a used r1 02-03 master cylinder. I instaled and it seemed to work well. After the instal i checked if the tyre was spining with no obstruction and it seemed it was ok. There was slight sound coming from pads touching the disk, but it seemed it was not affecting the weel.
Yesterday after riding for 10miles it felt like my front brakes were slightly aplied because from start postion it felt that it require more power same as increasing speed.
I cont understand if this might be because of the MC or because i havent riden a bike for few days :D
Try riding a bit and trying to not use the front brake. Does the disk feel warm?
When was the last time the brake Pistons had a clean, a build up of crud can stop them from returning easily.
Try riding a bit and trying to not use the front brake. Does the disk feel warm?
When was the last time the brake Pistons had a clean, a build up of crud can stop them from returning easily.
The caliper and pistons were cleaned when i changed to R1 master cylinder. I was rideing today in the morning and it felt fine for few miles and then again it felt like front was slightly slowing me down and the maneuvers were getting a bit more harder. I usually ride at 4k rpm. Today it felt that i needed more throttle as on what felt a usual throttle postion only reached arround 3.5k rpm
I will try tomorrow morning and tonight if i get a chance to see if the disk get warm
andrewsmith
07-11-15, 09:33 AM
Look at the master cylinder sounds like it's not allowing fluid to return
sent with all the fury of a clogged drain!!
squirrel_hunter
07-11-15, 11:03 AM
As a suggestion, not from personal experience but from reading about others, what lever are you using?
I have heard that some of the cheap brand copy levers are not the best quality and can be activating the brakes even when you think they are not...
Fen Tiger
07-11-15, 11:40 AM
I would have a look at the master cylinder. Will probably require dismantling and a clean. Rebuild with a new seal kit and ensure the return pinhole to the reservoir is clear. Also make sure the lid vents are clear and the rubber bellow and insert are installed correctly.
I would have a look at the master cylinder. Will probably require dismantling and a clean. Rebuild with a new seal kit and ensure the return pinhole to the reservoir is clear. Also make sure the lid vents are clear and the rubber bellow and insert are installed correctly.
Could it be baucause its not an original master cylinder ? Because i dont want to waste money on rebuild kit if on the later date i will need to get new master cylinder
Fen Tiger
07-11-15, 02:44 PM
The fact that the MC you have fitted is not the original should not cause the brakes to not release.
Suggest you try and establish with more certainty what problem you have.
I would raise the front wheel and spin it to see if the brakes are binding and whether it is both discs that are affected. Try applying the brake repeatedly and see if the situation changes. If all the pistons are putting pressure on the discs when the brake lever is released the fault has to be with that part of the system which is common to both calipers, either the common brake line, the splitter or the master cylinder function. If only one or other of the pistons is not retracting then that would point to a problem at the caliper.
Once you have a clear idea of what is at fault you will be in a better position to decide what to spend to fix it.
Would like to know how you get on. Hope it is fixed soon.
Fen Tiger
07-11-15, 02:49 PM
Certainly as SH has pointed out, if the brake lever is putting pressure on the master cylinder piston when at rest then that would be a problem.
Red Herring
09-11-15, 10:14 AM
On some master cylinders you can adjust the reach to the lever with an adjuster that alters the length of the piston actuating rod. People who like a long reach have been known to adjust this to the fully "out" position at which point the lever reaches it's stop (especially possible with an aftermarket lever) and if you turn it any further you are actually pushing the piston in....and it can no longer return properly.
Becomes a problem when the brakes get hot, the fluid expands a bit and the brakes can't release.
I know this from experience. Being stuck in the middle of the Cadwell Park straight on the 3rd lap with a front brake jammed on so you can't even get off the track is not something you easily forget...!
To answer your question the master cylinder not being standard won't be your problem. You either have binding brake callipers (you say you're checked that) or the master cylinder isn't releasing properly. Take the lever off and check the piston is coming fully back (you may need to remove the outer rubber cover). You will see if it isn't because there will be a witness mark on the cylinder. If in doubt rebuild it. Personally I wouldn't have used second hand brake parts without servicing them anyhow.
punyXpress
09-11-15, 04:34 PM
. . . but will the R1 m/c work properly with an SV lever?
Thank you guys for all your answer. This an update on the issue;
The reason the bike felt unbalanced was because front wheel was not aligned ( cant belive that i didint check it the first time ). Noticed it when was checking the calliper. After speaking with few people and checking the brakes ir looks like it might be the mc. The fliud is not returning to the cylinder as some of you advised that it might be the issue. So my plan is to rebuild the cylinder, properly clean it and put hel lines in.
Hopefully it will sort the issue completly. Will update if it worked once evrything is complet.
Once again thanks for support !
. . . but will the R1 m/c work properly with an SV lever?
Iam using original r1 leaver...
All issues are sorted, rebuilded the master cylinder, changed the lines and straightened the front weel. The bike feels a lot lighter and the braking is amaizing. I belive the issues might of been with the return hole as the cap had a lot of dirt buit up and it was real difficulty removeing it.
Once again thanks for evryones replys and help...
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