Master cylinder replacement

Post by **youngun** » Fri Jul 24, 2009 1:33 pm

Just got round to looking at my master cylinder as its got to go back in before the torsion bars go on. Mines the older style 7/8" bore one, and annoyingly its had it. The bores badly pitted and the piston is scratched to hell.
I see that the only replacements you can get are the 13/16" bore ones, could I just use one of these or does it depend upon what brake set-up im using?

thanks,
YG

Post by **bmcecosse** » Fri Jul 24, 2009 2:03 pm

The difference is minimal - just use the new one !

Post by **jaekl** » Fri Jul 24, 2009 2:45 pm

Look on the bright side. You're already for an upgrade to 8 inch brakes. The smaller bore gives you a bit more pressure per push at the sacrifice of travel to get the same amount of fluid movement. It's a 13.8% change in all parameters.

linearaudio · Post by **linearaudio** » Fri Jul 24, 2009 10:11 pm

jaekl wrote:Look on the bright side. You're already for an upgrade to 8 inch brakes......

Or even 9 inch brakes..........

Post by **bmcecosse** » Fri Jul 24, 2009 11:08 pm

Saying nothing!

Post by **youngun** » Sat Jul 25, 2009 11:43 am

Already done a 9" conversion. So ill just get a newer type MC....thanks for the help everyone!
Oh, should I go for a pattern one or genuine Lockheed?

YG

Post by **bmcecosse** » Sat Jul 25, 2009 11:45 am

youngun wrote:Already done a 9" conversion.
YG

I knew that - hence 'saying nothing' !

Post by **youngun** » Sat Jul 25, 2009 11:55 am

Ah I thought you were referring to the controversy we've had over this subject.........or were you and Im just having a bout of morning stupidness again?!!

Post by **rayofleamington** » Sat Jul 25, 2009 12:21 pm

Ah I thought you were referring to the controversy we've had over this subject.........

merely a storm in a tea cup

Post by **Dean** » Sat Jul 25, 2009 12:33 pm

youngun wrote: Oh, should I go for a pattern one or genuine Lockheed?

YG

Personally I'd go for genuine.

Post by **bmcecosse** » Sat Jul 25, 2009 6:22 pm

Ahh - but what makes the 'Lockheed' one any better than the 'pattern? I doubt either is made in Europe, never mind UK these days!

Post by **d_harris** » Sat Jul 25, 2009 6:31 pm

Isn't the only advantage of the lockheed that you can get a replacement seal set??

Post by **rayofleamington** » Sat Jul 25, 2009 6:48 pm

Ahh - but what makes the 'Lockheed' one any better than the 'pattern? I doubt either is made in Europe, never mind UK these days!

One difference is that the pattern ones had so many problems that some places stopped selling them. Lockheed ones have been known to be faulty when new, but not that often.

Post by **Dean** » Sat Jul 25, 2009 8:14 pm

bmcecosse wrote:Ahh - but what makes the 'Lockheed' one any better than the 'pattern? I doubt either is made in Europe, never mind UK these days!

When I replaced mine, I rang Bull Motif and they said we only do the genuine due to quality issues with the pattern. Which I guess is pretty much what Ray is saying.

Post by **bmcecosse** » Sat Jul 25, 2009 9:04 pm

I don't doubt the 'Lockheed' one IS better - i just wonder why! At one time would have been British Made - I doubt it now. Guess they still have some QC to protect their 'good' name!

Post by **rayofleamington** » Sat Jul 25, 2009 9:45 pm

At one time would have been British Made - I doubt it now.

up until a few years ago, they were still subbing it in the UK - no idea where it's made now though as my days of knowing anything about AP are long gone.

Post by **MikeNash** » Sun Jul 26, 2009 10:01 pm

Youngun,
I'd go for the "genuine" Lockheed. The design has a big bucket seal at the back of the piston as opposed to a ring seal about an eighth of an inch wide half way along the piston. IMO the Lockheed type rides over bore imperfections better and (I'm told) you can get replacements seals. I avoid the "patterns"; I've had a couple where the bore finish has been so bad that after 18 months they had ruined the seals.
I bought my "Lockheeds" from Bullmotif.
Regards, MikeN.