mk1b rear caliper - piston diameter?

[Jim-SR]

anyone got a mk1b rear caliper off of their car who fancies measuring the diameter of the piston in it? ive had a bloody good search of the whole internet and cant find anywhere that states the diameter. looking at pictures it appears to be somewhere around 20-25mm i reckon, but if someone could give the exact measurement that would be great :)

cheers
JIM

[Jiff Lemon]

Trying to find the same info here...

http://forums.twobrutal.com/showthread.php?t=8574

[Shorty]

I`ll disemble one of mine later tonight but noone else do it now cause i don`t want to spend the time doing it if someone beats me to it;)!!!!

[Jim-SR]

yeh Jiff it was that thread which made me think lol. just thought id start another thread for this one specific size as some people might not look in that thread, or brush over it, whereas this one is a touch more to the point lol

if i find out il add a reply to your other thread with it (or if you see it posted in here first you can add it lol)

and cheers shorty, much appreciated :)

[Shorty]

Hmm.. i might have been to fast there. Are the mk1a and mk1b different? If so then i can`t help. :( If same, i can:)

[Jim-SR]

measure it anyway, im not sure whether the calipers themselves vary or just the disc diameter and the carriers?

[OlberJ]

And when you're all done you can put the results into my Definitive weights/measurements thread.

Thanks,
Olie

[monkeymax]

Dug out my junk caliper (with useable piston), removed the piston and have it here with me. Have to pop out for a couple of hours... will measure for you when I get back...

-Max

[Shorty]

I get 33mm diameter. BTW, how acurate do you need? I have a micrometer and could probably take a bit better one tomorrow cause i couldn`t get it far enough out in the minute i was out to take an exact one.

[monkeymax]

Yup, 33mm diameter at the front that's visible with the piston in the caliper. The rear has 36mm diameter. However, that's approximate... I only seem to have a tape measure here and don't have access a micrometer (may be able to borrow one on Saturday if I see one of my friends...).

[Jim-SR]

rear diameter would be best, although im surprised theres as much as 3mm difference!! either way its about 11mm bigger than i wanted it to be lol

if its easy for you both to get a more accurate reading of the rear diameter then go for it, i can work with the numbers ive now got, but obviously having them as accurate as possible makes the calculations ive got to make even better :)

cheers guys