BRAKE CALIPER CAPSCREWS. S/S REPLACEMENT?

el-nicko · Post by **el-nicko** » Sat Jul 14, 2012 12:45 pm

Is it possible (safe?

) to replace the 4 capscrews that hold the two halves of the (3)calipers together (mine are really manky

) with stainless ones without draining and dismantling the unit? One at a time maybe? Has anyone done this? What type/size do I need?

Mike B · Post by **Mike B** » Sat Jul 14, 2012 1:51 pm

yes, done that

Just do one at a time

got a stainless pin as well.

Blackal · Post by **Blackal** » Sat Jul 14, 2012 2:03 pm

Just hot-bolt them - no problem.

I think they are M8, but can't remember the length.

Take one out, measure it and return it - then go out and buy the stainless ones.

Get decent stainless, though

make sure you smear oil on the stainless bolts (and if hot-bolting - I would use molykote, as you are not opening the caliper mating-faces)

Al

el-nicko · Post by **el-nicko** » Sat Jul 14, 2012 2:05 pm

Mike B wrote:yes, done that

Just do one at a time

Ooh, that looks nice

. Cheers lads. I'll pull one out and 'size' it.

el-nicko · Post by **el-nicko** » Sat Jul 14, 2012 11:03 pm

Well I've removed a bolt and sized it (M8x40) but nothing's ever straight-forward with BMW is it.

The head's a different shape from a standard cap screw and they're 'waisted' down to 7m/m for the part of their length that's exposed when they're fitted.

BTW, What's 'Hot-Bolt' mean Al?

Blackal · Post by **Blackal** » Sun Jul 15, 2012 5:11 am

Sorry - my post was a bit superfluous - I started it, read a couple of e-mails, and by the time I had completed the post - it had already been suggested.

Hot-bolting is just changing out bolts one at a time. More often than not - on live low pressure systems.

Al

slparry · Post by **slparry** » Sun Jul 15, 2012 9:15 am

Get in touch with Chris Shaw Stainless he'll sort you out

http://www.shawstainless.co.uk/

oyster · Post by **oyster** » Sun Jul 15, 2012 9:29 am

I straight swapped one at a time, M8 X 40; and ground the ends off if they protruded beyond the caliper body. Great fun getting the OE bolts out I recall. It is also worth remembering there at least two grades of stainless bolts (A2; A4 I think) + the awful inferior Chinese ones. I always fit marine quality. The price is a useful gauge.

el-nicko · Post by **el-nicko** » Sun Jul 15, 2012 10:01 am

Blackal wrote:Hot-bolting is just changing out bolts one at a time. More often than not - on live low pressure systems.

Al

Cheers Al, I learn something every visit.

Just ordered these (x2)

Dog Tyred · Post by **Dog Tyred** » Sun Jul 15, 2012 2:57 pm

I did mine with flanged hex head bolts rather than cap heads. Think they look a treat

DT

el-nicko · Post by **el-nicko** » Sun Jul 15, 2012 4:36 pm

They do look nice.

It's all very dispiriting. The front of my bike (calipers, discs, front engine cover, forks, bottom yolk) just looks crap.

northern donkey · Post by **northern donkey** » Sun Jul 15, 2012 5:08 pm

mine also look cr*p compared to yours,but this winter it will be on the top of my things to do it is bugging the life out of me

el-nicko · Post by **el-nicko** » Sun Jul 15, 2012 5:35 pm

I can see there may be a reason BM waisted (Disc clearance? Do they run that close?

) the OE bolts. But why go to the trouble of fitting a cap screw with a head shape that at least I've never seen before?

Blackal · Post by **Blackal** » Sun Jul 15, 2012 6:59 pm

I don't remember there being locating dowels between the two caliper halves.....

That being the case - the increased diameter at the cap-head end is for location of the two halves- I would reckon.

On more critical bolts (bottom end bolts) the main structure of the bolt is reduced from the thread diameter - to prevent stretch of the bolt in the thread-section. You'll often see short sections of the bolt increased out to the thread diameter - to locate the bolt in the hole.

Al

Hayden · Post by **Hayden** » Sun Jul 15, 2012 7:31 pm

Mine could do with doing also..

..along with a shed load of other things.

Anyone know what torque to tighten these to, 40Nm?

Steve