1275gt clutch and brake cylinder help

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ibby4585
Basic 850
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1275gt clutch and brake cylinder help

Post by ibby4585 »

Hi.

I know this is predominantly a MK1 site but I know some of you have gt's tucked away too.

Does anyone know what Brake and clutch Master Cylinders were used on a 80' GT please? Does it have a Bias too?

Mine are missing from my rebuild and I'm not entirely sure what it had.

I'm running the original 8.4 discs but I've upgraded to Metro 4 pot Calipers.

Also has anyone any pictures of the brake routing layout from cylinder to calipers please.

Thanks
Kris
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Spider
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Re: 1275gt clutch and brake cylinder help

Post by Spider »

It would have had Tandem Brakes, with a Front / Rear Split. I think some were fitted with the 'Green' Band MCs and some with the 'Yellow' Band. Both of these are still available.

There would have been an Interia Type Valve mounted in the RH side of rear subframe, these didn't have a spring, and didn't work on pressure, there's a BIG ball bearing in them that rolled up a ramp to activate the shut off valve within, these worked mainly how fast you were stopping. These are NLA, but can still be found in the odd place. They are actually a very good design, not only in the way they work, but that they give little trouble, though kits were never made for them.

The Clutch MC I'm pretty sure was the Tin Tank type that had the single groove in the main body just under the tank, bore size would have been 0.70"
ibby4585
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Location: Oxfordshire. UK

Re: 1275gt clutch and brake cylinder help

Post by ibby4585 »

Ok cheers.

Will try and hunt some pics down
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Re: 1275gt clutch and brake cylinder help

Post by Spider »

The Brake MC will be either a GMC227 (Yellow Tag) or a GMC167 (Green Tag), though I'm 90% sure it is the latter.

The Interia Valve (or Bias Valve if that floats your boat) is a 13H7757.

The Clutch MC is a GMC1008.
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