Metro Valves collets?
Turbo Mini Forums

When the metro came along it was endowed with valves which sported the 3 grove retaining collets!

Why this was so I am not sure,

anyone know ?

I have been told by "good" authority that under high RPM these have a tendency to come adrift ??

Has any one had any experience with this problem?

can you get race valves With this design ?

thanks chaps

good point ben i've thought the same to, as people have had the single collets running ok for years.

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i was always 'told' that these (triples) can pull through when using high rpm with high poundage springs?

I've seen the future and tbh its Pie

2 friends of mine had broken valves with the 3 grove collets when they used them with heavier springs. They broke at one of the groves.

The thought behind this idea is to allow the valve to rotate when in use.

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right chaps thats not too healthy.

i havent come across any race valves in the 3 grove valves ?

rimflows uses single collet holes. but the race valves (inlets) i got from minispares had the triple groves.

but as for high revs, turbo dont need to rev much behond 6k unlike NA race engines which sit between 6 and 8k all the time.

ive never had a problem with a raod engine using triple grove valves.

always looking for them bigger bunches of bannanas

cheers hoggy

I've had a lot of problems with collets and valve cap mismatches.

I bought a set of 'unbreakable' alloy valve caps from Minispares, and they all broke. I put it down to them being designed for the single groove collets. I've broken the standard steel ones too in the same way.

I still use the 3 groove valves but now with a very carefully chosen set of caps and collets thgat I know are a pair. Been ok so far.

Wil

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

so wil, what been posted on this thread is...

dont use excessive spring pressures in the 3 groved type. & HIGH RPM

also dont use the top cap retainers off the single collet type together with 3 collet type valves

dont mix and match!

Oh! & they do make race valves in the 3 groved type.

Edited by BENROSS on 31st May, 2005.

A good summary of the thread Ben.

Fastest 998 mini in the world? 13.05 1/4 mile 106mph

The 3groove retainers have got a small "lip" or a ring in the centre of them. This lip goes upwards, whereas the single groove retainers have got a 45degree bend downwards.

I like the single groove ones better as they are much easier to fit :)

Never had any problems with neither.

Many bikes and ohter makes of car uses 3 grrove ones in racing as well. Maybe the material is crap, not the design.. I'd use the original A+ 3 groove valves in ANYTHING roadgoing any day, due to the fact that these wear better than anything else on the market. They're MUCH better than A single groove ones and MUCH better than Minispares race valves. These are soft. The Rimflos are supposed to be hardened as well, but I haven't used these suffieciently to have any good or bad experience.