Yamaha TRX850 Enthusiasts Forum

On the weekend I cleaned the brake pistons and changed the brake fluid to try to eliminate what had become a kind of 3 stage feel at the lever...as in the lever would move to a position, hesitate, then on to the next...with corresponding jumps in brake effect. Quite unsafe really.
With the cleaned pistons and new fluid I still have a little bit of a 2 stage feel. While bleeding the brakes the lever operated smoothly. Would this indicate a master cyclinder overhaul is needed?
Seems a simple enough job...just wondering if anyone has experienced the same and did the overhaul fix the ussue, cheers.

Dav wrote:On the weekend I cleaned the brake pistons and changed the brake fluid to try to eliminate what had become a kind of 3 stage feel at the lever...as in the lever would move to a position, hesitate, then on to the next...with corresponding jumps in brake effect. Quite unsafe really.
With the cleaned pistons and new fluid I still have a little bit of a 2 stage feel. While bleeding the brakes the lever operated smoothly. Would this indicate a master cyclinder overhaul is needed?
Seems a simple enough job...just wondering if anyone has experienced the same and did the overhaul fix the ussue, cheers.

Dav, are you using the shorty levers....maybe so , but i had the same experience alebit with my short levers as they werent pushing in the middle of the master plunger pinion.....basicly jack knifeing the plunger and causing a hang up effect...my shortys were for an r6 .
fixed the prob by alloy welding an extension to the lever bracket...then , fileing back to fit.
if you DONT have an aftermarket and different model Yamaha set and made in China...dissregard my thread...

Cheers Alex...I do have aftermarket items (thundercat fitment)...will check, but they've been on for months now and the weird action is a recent development. I might chuck the stock lever back on and see how it behaves

If you have bluespots and using a R6/1 m,cylinder or need one cheap, surf around as I found a brand new one for $76 to my door from the UK.
There was some other OEM ones from Hong Kong for close to $100. By the time you pay for a kit it's good value and gives you a complete running spare (be it a little iffy) to get you by just incase or you sell it and go back to std calipers. You'll always get a good price here in OZ for your bluespots and 14mm M/C as a package.

Cobbs, am still using the stock calipers and m cyclinder. I went bluespots with the previous trx but didn't know to match the master cylinder and wasn't impressed with the wooden action

MMMM sounds familiar.. I had Janet saying something like that to me over Easter. About me NOT BEING IMPRESSED and me spose to be the MASTER of the realm and WOODEN GET OFF MY ARSE to MOW THE LAWN .....walked out screaming something about the last brake...

If you're not careful Cobba, she'll impress that wooden spoon into your face.

M/C rebuild is a piece of the proverbial, definitely worth it in my opinion. I think I got the kit on eBay for about $20 IIRC. I think I took some pics when I rebuilt mine, it wasn't pretty.

Another trick is to make sure your lever pivot is well greased, when the grease dries out/gums up it can affect the feel & action of the lever.

Cheers MV, I think I'll overhaul it anyway. The Haynes tinkerers manual says every 2 years so mine's over 7 x overdue
Update: I swapped back to the stock lever, no difference (the aftermarket item has a nice spur)...just waiting on the MC rebuild kit to arrive

From the grave...m/c overhaul done today finally...kedo kit...easy on-bike job (screw you Haynes!)..perfecto progressive mellow feelings