Brake cylinder bore sizes

[Richard B]

MikeyB wrote:

Front brakes are Spit, rear are Vit - Vit calipers/discs are larger (same as GT6), think this would take into account heavier engine.  

Thats the Vitesse 1600 brake spec then. Type 12 (or 14?) Calipers & [s]nine[/s] 8'' Drums or am I talking bullshit again?  :B

What size M/C did the 1600 have?

ps yes I was Vitesse is 8'' not 9'', 2000 & Stag is 9''

[junkuser]

Was thinking early Vit had 7" drums.    Wrong!
8" drums would require less cylinder diameter to achieve same breaking effect.
The rear axle loading on a Herald would be greater than on a Spitfire so there is another variable to throw in.

[mikeyb]

CharlieB wrote:

Might be better to fit smaller rear wheel cylinders to restore balanced braking?

brake balance seems fine, it's pedal travel I'm trying to eliminate.

[junkuser]

Was the hole in the upper end of the brake pedal lever a neat fit on the clevis pin?
Is there full movement of the master cylinder?
If the rear brakes are correctly adjusted and there is no air in the system then deteriorating hoses could be the cause but these would most likely give a spongey feeling to the brakes.
Will be interesting to hear what you discover.

[Nick Jones]

MikeyB wrote:

hmmn, others have suggested that . . .  but they are Goodridge Steel Braided - tell me if you think different, but I don't reckon they go squashy?

I think you have that covered then.... dunno what else to suggest.  5/8 master should be ok with Spit calipers - not sure the rear wheel cylinders make much difference on that score.  Not normally too hard to bleed either, gravity usually does the job on my Vitesse.

I would say clamp off various wheels to see if you can isolate the problem, but thats a challenge with braided hoses....... :-/

Nick

[mikeyb]

The only other thought that has come to me is to look at the pedal box, ithe accelerator has been modified to get rid of the organ pedal, but the whole lot feels skewed to the right to me  . . . or are all Heralds skewed this way?

[ferny]

All Heralds go a long way to the right.


So the brakes actually work fine, it's just the pedal travel which is the problem? If so it must be related to the pedal. You say it's been modified, so maybe the position has been changed and now it needs a longer through? I assume all MC pushrods are the same length. I notice Canley's have an adjustable one listed with a part number and no price. Could be an idea... Won't be hard to make.

[thescrapman]

ferny wrote:

All Heralds go a long way to the right.


So the brakes actually work fine, it's just the pedal travel which is the problem? If so it must be related to the pedal. You say it's been modified, so maybe the position has been changed and now it needs a longer through? I assume all MC pushrods are the same length. I notice Canley's have an adjustable one listed with a part number and no price. Could be an idea... Won't be hard to make.

No, the brakes don't work OK, Mike just has nerves of steel, I have underpants of steel, and they weren't enough to hold it all in when I had a go!

It is spongey squish almost all the way to the floor, so it is moving fluid, then it was like the same feeling as when you have cooked your brake pads, massive amounts of push resulting in only a slow deceleration.

Cheers

Colin