650 front master cylinder.... woes

[sparki]

would like a good, working front master cylinder that i can paint and bolt onto my 650 project please....

stripped mine, replaced bits and cleaned it to look fantastic.... 'cept it locks up whenever i bleed it. almost as though the plunger isn't popping far enough out to relieve the pressure. thought it was too much fluid at first but it's had a replacement seal kit, lid, seal etc and it still won't work.. the lever has some "free play" in it when bled and feels like the plunger isn't coming all the way out if that makes sense?..... maybe i bought the wrong replacement rebuild kit i have no idea. can't seem to get the *&^%$ circlip out now either to check it all out. anyway after too many hours of messing around and fluid and and and.... tbh i want to replace it with a known good one before i launch something through a window....

so anyone have anything i can buy plse? i don't want to rebuild anything. simple paint and use.... if it isn't like that i don't want it

thanks

[bobster]

Hi sparkles
Check the 2 tiny little holes in the reservoir..............1 lets fluid in to the brake line when u pull the lever and the other is a return when you release the lever, if ones blocked it will just pressurise the system.

Ive seen this quite a few times in the past.

[sparki]

it was completely stripped, ultrasonically cleaned, holes checked, cleared and a new master cylinder kit installed... now for the love of god i cannot get the &^%$£ circlip back off to make sure it's all together properly

there's one big (presume for fluid) and a much smaller hole (presume breather). big one's clear cos there's fluid in the system and the small one had a piece of wire in it to make sure t'was clear. the other thing that has me a lil confused is that when the lever is bolted on there is a gap between the bit on the lever that presses against the plunger so the lever can actually move back and forth approx. 5mm without being in contact with the plunger. this in my limited knowledge is saying that the plunger isn't travelling all the way out but without being able to get the cir clip off i'm stuck as to being able to check it out

really really pissing me off at the moment this thing

[callyboy]

Steve. You got circlip pliers?

Pete

[sparki]

sure do... nice long thin ones that get in the hole nicely... compress the handles and they pop straight out of the holes before i barely get a change to move the clip... looking at how much it compresses before the two ends actually touch however is minimal so looks like the edge of the clip groove is holding the clip back thus the pliers just slip off...

[sparki]

tried small flat screwdriver to prise at the same time too... to stop it popping back into the groove... no go. had a gut full of it as each step of the way with this feckin master cylinder it's bit me... every single thing i've done to it it's stood there and pulled two fingers at me..... feckin original suzuki rebuild kit too... you wanna price those?... lol

[fossie]

Sparki the original 650 master cyl is a complete clear plastic thing with a black top, Ionly say this as there is nothing to paint.

So if you got a rebuild kit for a 650 and your cyl isn't from a 650 the tolerances may be wrong.

[sparki]

the reservoir is completely plastic. the cap is black with 4 screws. the base is aluminium that is now black...

mine looks like the attached... std master cylinder isn't it? the bottom bit is what is painted...

[katscott]

I rebuilt my master cylinder after a complete strip down. taking the reservoir off so I could repaint the base, removed the nuts captured in the clear plastic a replaced them with stainless ones, suzuki rebuild kit and new reservoir cap. It didn't mater how many times I squeezed the lever the mother hubbard would not push fluid to bleed the brakes. I checked part no's on cmsnl and the 650 wears the same as the gsx1100et. I couldn't find one on evil bay for sensible money so I sourced one from a gsx400f (weirdly the same as the gsx750et) and put in a Japanese pattern seal kit and bingo everything worked. I also worked on the premise if the master cylinder could stop the 750 it would work on my 650Kat. The master cylinder looks original and only the pedantic would point out it's not the right one for the bike. Hope this helps

[fossie]

Well it is the correct one sparki,, all I can say is I once used an aftermarket kit with he same results, put old kit back in and it worked fine. Turned out to be the seal too tight.