Hi guys got a question on a Ktm sxf 350 master cylinder. I've got no back brake nothing at all push the foot brake and it goes straight down to the stop no resistance at all I thought I might have a air lock so tried bleeding the brake but the fluid sat in the resovoir and didn't move when I pumped the brake so I assume it's the master cylinder has any one repaired one before is it easy I have just received the master cylinder repair kit but looks tricky
Hi guys got a question on a Ktm sxf 350 master cylinder. I've got no back brake nothing at all push the foot brake and it goes straight down to the stop no resistance at all I thought I might have a air lock so tried bleeding the brake but the fluid sat in the resovoir and didn't move when I pumped the brake so I assume it's the master cylinder has any one repaired one before is it easy I have just received the master cylinder repair kit but looks tricky
I'm a wee bit confused (not unusual). If there is no brake pedal resistance and the fluid level doesn't drop (ie leak) then the seals must be okay or alternatively they are not being sufficiently pressured by application of force on brake pedal. this would lead me to question the mechanical integrity of the linkage between the brake pedal and the master cylinder, which iI'm sure you have investigated, so I remain confused.
Hi, I did mine 6 months ago, its not too difficult, basically it is just a seal kit for the plunger in the master cylinder, you strip the plunger out( thats tricky as it held in by a circlip) and its difficult to see but I just cut out the outside rubber shroud, just be careful when you put all the seals in that they are seated correctly and face the right way, what can happen is a seal can be letting by, that way the fluid level doesnt move, while you are at it, it may be a good opportunity to flush through with new fluid, good luck. any problems phone ktm LOL
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Definition of prostrate: " lying stretched out on the ground with one's face downwards."
so I still don't understand when I asked the lady for a prostrate massage she got upset?
sorry, just looked at your pics what you have is a complete replacement set plunger and all, you could have just bought the seals much cheaper but what you have is easier I guess just replace the lot 321 youre back on your bike..............
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Definition of prostrate: " lying stretched out on the ground with one's face downwards."
so I still don't understand when I asked the lady for a prostrate massage she got upset?
Obvious thing but often overlooked, make sure the bleed nipple is not blocked. Also the calipers and pads can become partially seized so check that everything is nice and free there.
Changing seals is easy, flush through with fresh fluid and it should be okay. Sometimes it is better to allow fluid to percolate through rather than pump the lever to try and force it through, take the bleed nipple right out preferably with the bike facing up hill so there is a fall towards the caliper end and wait until the fluid comes through on its own, then pump out any air left in the usual way. I always do this and have done on cars and bikes for many years as there is less likelihood of tearing the seals especially as when the cylinders get old they can become rough on areas not usually where the seals operate on. For this reason it is best not to operate the lever whether it be clutch or brake over its full length of movement when trying to bleed it if the seals and cylinders are old.
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Walk a mile in another man's shoes. ...and you will be a mile away... and have his shoes..
Thanks for your help guys I replaced the piston and bellows turns out the brake adjustment was not right and the plunger wasn't returning enough to allow the bellows to draw the brake fluid into the chamber took me a while to figure that out but was basically exactly what Pete said so all sorted and working now. Thanks
