Out on the z1000 on saturday....while was out the front brakes started to bind....pulled over waited for them to cool down, popped the calipers off and prized them apart a little and returned home. Took the calipers off and drew the pistons out and gave them a clean...assuming all would be ok but no.....on the way to work this morning and theyre still dragging...only a couple of miles to work and when i got there, they were warm but not anywhere near hot....anyway, pulled them apart tonight completely and the weather has gotten in around the bottom of the caliper and i hasten to say eaten away at the bottom of the caliper....the internal oil seals appear to be ok (as in the alloy around them) but as i say at the edge near the dust seals it is very thin....my plan was/is (depending on what you lot say) to get them blasted off and recoated in Cerakote (Black gloss). But, im not sure if the blasting might take the rest of the edge away.....kinda one of those things im gonna have to do otherwise ill never know but having said that if i dont....then theyre pretty scappy and unusable as the weather will just continue to get in there (my z is my daily all year round whip). Alternatively i scrap them and go for either a set of m4's or m50's....opinions please..!
Metal - from the caliper itself...as you can see the dust seal round the bottom is there but thinner....
I know i'm stating the obvious, and surely this has crossed your mind comfy - have calipers been aftermarket plated by any chance? - if so, it could be as simple as bores weren't masked? - hard to do properly in the first place anyway. I've had many a caliper corroded internally but as long as important parts are ok - i.e. bores and hydraulic seal lands (and not corroded to the point of integrity failure/leaking of course) then i've gone ahead and rebuilt and they've been fine. Best find what is actually binding first, and there does appear to be a lot of silvery stuff present, e.g. - could be unwanted/non-std coating actually on bores and seal lands, and the latter will definitely cause binding easily.
Yep - appears so....should have gotten them cerakoted then!.....i might take them down to the cerakoter....get him to blast them and if the thin bit of rim round the dust seals stays intact...take a chance and see if they work....price of calipers has shot up....wasnt expecting to buy a new set...! My theory is, if the blasting and then cerakoting works then the cerakote "should" seal the alloy in.....but as i say i dont think you would be able to tell...theyll have to be blasted to find out..
dont write of the possibility of flexy hoses being partially blocked. not that uncommon in the motor trade. or even the master cylinder not fully returning. both of which will allow the fluid to get to the callipers but wont fully release until sitting for several mins.
don't get them to blast internally! - it looks as though it's coming off by itself quite well. It's a delicate area as far as what you do next and trade would replace and not fuck around anymore with them now tbh. There's a pair on here for £700.. no idea what the going rate is now.
Yeah - he can mask that off...even if the outer edge is intact albeit thinner as long as its got the integrity to hold a dust seal (which isnt under pressure) then i reckon ill be ok....yeah - paid 700 for mine a few years back...
Aluminium oxide has no strength. If the corrosion has eaten into the critical parts of the caliper, the remaining thickness of “good” material may be so thin that it cannot withstand the stresses due to the hydraulic pressure applied. It may not fail catastrophically however the repeated application of pressure due to braking (and thermal heat cycles) may lead to crack initiation and subsequent propagation, then catastrophic failure.
Are the Hel's that good? (ive always wondered what theyre like) - was trying to keep it all brembo (got a nickel plated one on the rear)
if your rear caliper has also had additional plating on the bore and it's seal lands then be prepared for more brake binding.
The rear one was a brank spanker a few years back...its near perfect at the moment so im all ok....the fronts are old....id hazzard 30 years....they came off an old Spondon GSXR...
I’ve had the hel calipers on my blade (like you it was a daily) matched with the master cylinder think that set up is better than what I have on my 1299 now but each to there own .recorded the highest mileage they’ve known on them, just over 50k miles in just under 4 years and never had a problem with them,will guarantee they will also be the best customer service you’ll have also
