Rb piston options

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Bensmith225
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After destroying my monza (asso piston lost its skirt and Jammed up doing 80) I’ve acquired a used rb22 setup the only problem being its got an asso piston and after my recent mishap I’ve lost faith in them. Question is has anybody used the Ron moss ts1 piston in an rb? I’ve heard nothing but good things from friends running them in ts1’s


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bazza3004
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Used a ron moss piston in a build i did for someone a while back. Hes had no issues so far but have to say the piston felt heavy compared to others
Bensmith225
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Was that an rb? After the mess my monza was in I’d rather have a heavy strong piston haha


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GTFOMWSC
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try a Wossner not had any issues with the ones i'm using quite expensive but it's still going strong.Not in RB's but Monzas, my RB20 which has just been built has an ASSO in it so now you have me concerned how many miles had you done on it before it went?
the man don't give a f@@k
Bensmith225
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About 4000 miles on that piston, I spoke to Harry Barlow about it and he said there’s a design flaw on the windows that makes them prone to crack. He does his own reinforced pro porting version of it but that’s not cheap either and I’d go for the wossner but I’m running low on money so looking for a cheaper alternative, if the ring pegs don’t interfere with the ports I should be fine with the Ron moss mitaka one but I cant get hold of one to look at it


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OAP
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I have never tried our TS1 pistons in an RB22 and to be honest I think there will be an issue with the ring pegs running over the boost ports. In fact they are really only alright on the Standard TS1 without any alterations to the boost ports.

Bare weight of the piston is approx 291 grams, inlet side is thicker as were the original TS1 pistons because of the cut outs.

The newer type pistons available for the RB's are now the same thickness
on the exhaust & inlet skirts!
Bensmith225
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Right thanks that’s the information I was after


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Scooterdude
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Right I’ve just been and found a forged MRB piston i took out of an rb225 i was doing for someone, obviously the ring peg position was correct for the rb as it had been in for a few years and was running well.

Ive also got a meteor cast coated rt reed piston with the ring pegs in exactly the same position as the MRB one (This could be a good option for you)

Also got an Asso that Rayspeed sell for the rb, interestingly if you look at the side of the piston with the reed windows facing you the left hand peg is in the same position as the other pistons but the right hand peg is 7mm further round to the right.

Couldn’t comment on the Moss or the Mitaka but they do look very similar to the Asso with the thicker heavier walls. Never seen the proporting one so couldn’t comment.

Weight wise, the mrb is 300 grams cast coated meteor 291 grams Asso 340 grams (all with pin circlips and rings fitted.
Bensmith225
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That’s interesting. I’ll have to have a look into those, Harry Barlow did mention he uses a dt250 piston made by the same manufacturer as his pro porting ones that he uses on his steel liner ts1 conversions that only cost about £60, I might go and measure that up too, the meteor piston is a good shout though
Muppet
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Bensmith225 wrote: Tue Feb 26, 2019 9:39 am That’s interesting. I’ll have to have a look into those, Harry Barlow did mention he uses a dt250 piston made by the same manufacturer as his pro porting ones that he uses on his steel liner ts1 conversions that only cost about £60, I might go and measure that up too, the meteor piston is a good shout though
Is it this one ? https://yambits.co.uk/dt250-piston-kit- ... 13356.html
C’est la vie
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