Stripped threads
 

There was a constant tiny dribble of fluid from the banjo bolt on my front brake master cylinder, and I've now over tightened it and stripped the thread on the m/c (no need to say - stupid ****).
Does anyone know of a company that can re-thread it - I asume they'd have to drill it out and put a barrel in.

TIA,

Iain

I would not recommend repairing the thread of such a critical hydraulic joint. You wouldn't want the repair to fail just as you are entering that favourite corner - just thinking about the consequences makes me feel ill!

Just my opinion though..........

R X

I'd have though you could get a local engineering firm to helicoil it for you.

shouldn't cost too much, probably around £20.00

Although I have a m/cyl from the early model (916 era) without reservoir or lever you can have for £20 inc posting. You could swap over lever and reservoir from yours then.

Or a cheapy upgrade

http://cgi.ebay.co.uk/ws/eBayISAPI.d...6547 109&rd=1

I'd go with Ricky on that one. Don't even contemplate a helicoil in a hydraulic circuit.
The insert won't seal and you'll lose pressure and therefore the brakes. Replacement is the only viable solution i'm afraid.

There's usually a couple on ebay

The DD boy's are snatching them off eBay for their twin disc conversions!

Aargh - radial master down the swanee then!
Thanks for the offer Mr S, I've got a stock brembo I can use for the mo'. I originally tried to fit one of the 749/999 radial ones a while back but it didn't sit with a stock 748 clip-on set up.

Wiser but poorer!

Oh bugger, didn't realise it was a radial.

Why not call a hydraulic specialist and see what they suggest?

I'd be very surprised if it can't be repaired as the pressure's not that great compared to some hydraulic pumps out there.

Maybe it's possible to tap the next size up and use a bigger banjo?

Iain,

Give James Walters at Brembo UK a call on 01908 220777 for the definitve answer about repairing.

Strongly suspect it's new M/C time though. :(

Cheers, Neil.

If its done properly I can see no reason at all why a Heli coil insert would not work in a master cylinder.

Thanks Neil; its a Disiciacci (sp?) m/c so Brembo might not be keen on giving advice. Just been on the Redracingparts site to see if they sell the m/c as a separate component but no luck, you have to send it off for repair/replacement.

"That'll teach me" for the thousandth time. Mind you if it's the thousandth time 'it' evidently hasn't taught me...:)

That's the M/Cyl I have. The CNC machined one.

Call Pirtek see what they say.

http://www.pirtek.co.uk/site/Dynamic...lang=1&page=10

Glad to see a full range of opinions as usual...
Mr_S, called Pirtek and though they only do hoses and fittings they passed me on to a company called West of Scotland Engineering who should be able to repair this, but don't usually do motorcycle work, so it depends if I catch them in a good mood!
Anyway, thanks for all the replies.

Iain C

The pressure can be up to 250 bar which is around 3500 psi i think.

The pressure can be up to 250 bar which is around 3500 psi i think.

thats enough to send a fragment of metal of around 8.5grains in wieght at a speed of over 850 feet per second giving you velocity of around 12-13ftlb=== thats the equivilant off an air rifle pellet at point blank range!!!!!

useless piece of information i know-but thats the sort of pressure your'e dealing with!!!

be best to get a new one i think!!!!!!

[Edited on 12-4-2005 by monstermob 998]