Hairsy Posted February 16 Share Posted February 16 If you’ve had the system apart, rebuilt with second hand replacement components in place, and now you’re still getting old fluid out of the replaced components then you haven’t bled the system fully. At this stage, I would remain optimistic that a thorough bleeding could solve your problems. Just one question - did you replace all the copper crush washers with new? Quote Link to comment Share on other sites More sharing options...
k3lv Posted February 16 Author Share Posted February 16 Still no joy even with the correct caliper this time ...I've bled the things every way possible, and I can still pull the lever to the bar , it's about half way when the brakes bite ....they pass an MOT brake test but , fail MOT because the lever reserve travel . Quote Link to comment Share on other sites More sharing options...
Simon Davey Posted February 16 Share Posted February 16 You say you haven't changed the lever, but is it possible it's bent? If it's bent or damaged at the pivot point, it won't be noticeable. How far do you have to stretch your fingers to grab it? Can we have a picture.. Quote Link to comment Share on other sites More sharing options...
k3lv Posted February 16 Author Share Posted February 16 1st pic is where it sits (on number 1) 2nd pic is where pressure really starts to build Quote Link to comment Share on other sites More sharing options...
Simon Davey Posted February 22 Share Posted February 22 Blimey, I'm sorry I missed this. If that's where the pressure starts, it looks perfectly alright, but yes, coming back to the grip is puzzling. I wish I could help. Quote Link to comment Share on other sites More sharing options...
k3lv Posted February 28 Author Share Posted February 28 On 22/02/2024 at 18:37, Simon Davey said: Blimey, I'm sorry I missed this. If that's where the pressure starts, it looks perfectly alright, but yes, coming back to the grip is puzzling. I wish I could help. Hi thanks for the reply , yeah it is puzzling indeed , the new MC rebuild kit I put in decided to die ....so that was fun , although I think the seal was a little too large so it must have snagged an tore , new MC kit went I today but still pull the lever back to the bar (easily) .......is there any difference between a 600 and 750 MC ? Quote Link to comment Share on other sites More sharing options...
k3lv Posted February 28 Author Share Posted February 28 Just tried vacuum bleeding ....again and still only gets to a certain point and nothing .....tried reverse bleeding but could not get the fluid in ....fresh out of ideas now .....might just search eBay for a MC Quote Link to comment Share on other sites More sharing options...
RideWithStyles Posted February 28 Share Posted February 28 (edited) just thinking on looking at that picture, is the lever out so much that you are able to just leveraging too much so it seems to be too much travel? hear me out. cos the mc piston will only move so much regardless of your lever action. the lever number only relates to it starting point from the grip not its actual stroke length... lets see measure the gap between the grip and the back of the lever (black marker pen the spot) when pressed in - whats the gap on one? X mm/cm. do the same on 2, 3, 4, etc, how much does that change and is it linear? or does it stop at the same point mm/cm away from the bar every time? Edited February 28 by RideWithStyles 1 Quote Link to comment Share on other sites More sharing options...
Simon Davey Posted February 28 Share Posted February 28 (edited) I just cant help feeling that it's the wrong lever. Looking at the second picture where it starts to apply pressure, the lever has already moved the piston in quite some distance, but shouldn't it have only moved the piston a small amount? It's like the angle of the lever isn't quite right. Or, the wrong MC. Edited February 28 by Simon Davey Quote Link to comment Share on other sites More sharing options...
k3lv Posted February 28 Author Share Posted February 28 Yeah my 1st thought was maybe a 600 MC had been put on by mistake....but measured the piston at 15.8mm which is the right diameter for the 750 , the stroke is really long then it applies pressure right at the last minute.....even with the lever off and me using something else to push it in ....I'm out of ideas now. Quote Link to comment Share on other sites More sharing options...
Simon Davey Posted February 28 Share Posted February 28 You've got the membrane (don't know what it's really called) under the lid of the MC? Just can't think where the heck is that pressure disappearing off to???? Quote Link to comment Share on other sites More sharing options...
RideWithStyles Posted February 28 Share Posted February 28 the only other thing i can think of left without literally changing the item while assuming that youve done everything else correctly. is there are two recesses within the MC, one is for the cur clip of the piston and the second is the one for the dust seal, its quite easy to put the pistons cur clip on the outer seals recess so the piston will still work and finally seal but it will further out so the throw and the action will be further... Quote Link to comment Share on other sites More sharing options...
Stu Posted February 28 Share Posted February 28 @k3lv have you got the tociko calipers on the bike? If so get rid of them! they are shockingly bad You can get a set of nissin calipers that bolt straight on and are much better Quote Link to comment Share on other sites More sharing options...
k3lv Posted February 29 Author Share Posted February 29 Simon , yeah got the little membrane that's in good condition no tears or holes . Ride, yeah ive double checked things like that ....it's usually something like that to catch me out , but all is good Stu, yeah it's the tokico calipers, I keep looking for nissin calipers but can never find any that will fit Quote Link to comment Share on other sites More sharing options...
RideWithStyles Posted February 29 Share Posted February 29 if you someone with an engineering back ground or a bike shop that does fabrication. a milling machine will do the job of making you a adaptation bracket if there isn't one already on the web? Quote Link to comment Share on other sites More sharing options...
RideWithStyles Posted February 29 Share Posted February 29 those Toks set ups wernt the best from new from there design . if it always stops at the same point with the same brake pressure to the discs to slow you down regardless of what number the lever is at nothing is particularly wrong thats just what is..especially at this point when pretty much everything has been changed and going off word. if it seems to travel less at each number then when you go to mot slam it on number the higher number so it doesn't seem to have a long throw lever action and it will pass. Quote Link to comment Share on other sites More sharing options...
k3lv Posted February 29 Author Share Posted February 29 Well I took for MOT and it passed all the brake test it was just the lever travel ...as it could touch the bar , had a play today another bottle of fluid down and still the same result.......however I stuck a nut between the MC piston and the lever ,6mm was too much it made the bike very hard to push , put roughly an 8mm bolt between the lever adjustment bit and that was better but not as good as shimming the piston . Anyone else got an old srad to compare levers ? Quote Link to comment Share on other sites More sharing options...
husoi Posted February 29 Share Posted February 29 Why not drill a 2.5mm hole where the lever pushes the MC piston. make a M3 thread and insert a wee bolt. Then you can adjust the bolt to your desired position. 2 Quote Link to comment Share on other sites More sharing options...
k3lv Posted February 29 Author Share Posted February 29 43 minutes ago, husoi said: Why not drill a 2.5mm hole where the lever pushes the MC piston. make a M3 thread and insert a wee bolt. Then you can adjust the bolt to your desired position. already on it .....but I don't own a drill bit or tap small enough , so gonna get them ordered 1 Quote Link to comment Share on other sites More sharing options...
Simon Davey Posted February 29 Share Posted February 29 That's a great idea. Just a grub screw would be perfect. Quote Link to comment Share on other sites More sharing options...
husoi Posted February 29 Share Posted February 29 3 minutes ago, k3lv said: already on it .....but I don't own a drill bit or tap small enough , so gonna get them ordered I would offer my taps but not worth the distance. 1 Quote Link to comment Share on other sites More sharing options...
Hairsy Posted February 29 Share Posted February 29 Can I please suggest caution. That solution might get you the brake lever you want for now but you haven't actually identified the problem that you're solving. I'd be super nervous about masking the symptom without first understanding the problem. In the list of critical functions on a bike, the front brake is pretty high up the list! I'm really sorry that I can't offer any suggestions - but do be cautious. 2 Quote Link to comment Share on other sites More sharing options...
k3lv Posted February 29 Author Share Posted February 29 (edited) 22 minutes ago, Hairsy said: Can I please suggest caution. That solution might get you the brake lever you want for now but you haven't actually identified the problem that you're solving. I'd be super nervous about masking the symptom without first understanding the problem. In the list of critical functions on a bike, the front brake is pretty high up the list! I'm really sorry that I can't offer any suggestions - but do be cautious. Yeah this is gonna be my last resort and short term fix until I can either solve the issue ....or replace the entire system Edited February 29 by k3lv Quote Link to comment Share on other sites More sharing options...
k3lv Posted February 29 Author Share Posted February 29 45 minutes ago, husoi said: I would offer my taps but not worth the distance. Would be a great ride though 1 Quote Link to comment Share on other sites More sharing options...
husoi Posted February 29 Share Posted February 29 (edited) Not the first time the friction bit of the lever gets worn enough to start to give problems. A good inspection of both the lever and the end bit of the MC piston for extra wear should help the investigation. and yes @k3lv can't go wrong with a trip to Scotland Edited February 29 by husoi 1 Quote Link to comment Share on other sites More sharing options...
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