Relining a Rapido 250

[corrado]

Mates fecked his Rapido 250 big style, lost a gudgeon pin circlip down the barrel.
Can it be sleeved smaller, say 70mm?
Can't see why not.

[sean brady scooters]

that sounds like an improvement to me...

[cezeta]

why would you want to sleeve it smaller?

[corrado]

why would you want to sleeve it smaller?

So that next time it goes bang he can rebore it. The pitfall of a 250, no oversizes.

[joespeed]

why would you want to sleeve it smaller?

So that next time it goes bang he can rebore it. The pitfall of a 250, no oversizes.

oversizes are available ,but i can imagine the depth of the grooves left by the circlip!

[corrado]

Yes, just noticed that AF do a 72.4mm piston, but the barrel damage looks terminal in the pics he sent me.

[tavspeed]

i'm sure one of the specialist 2-stroke engineers will be able to sort you out, pjme engineering comes to mind,i am running rapido 250,and seized it at 300 miles,cleaned piston and bore up and seems ok.how many oversizes do af do on this kit,also could i put a 200 barrell back on the casing,bearing in mind the neck has been machined larger,does the spigot need supporting by the neck,the spigot on a 200 barrell seems pretty strong,cheers all.

[carlos fandango]

Ive just sleeved a RB250 down to 71mm at pjme (£140) with a MB piston and lowered port timings at the same time. In a Quest for more torque only done 30 miles
so far so not run in yet.

[Knowledge]

Carlos,

That sounds like a very sensible idea. That might be a very wisely spent £140.

Let us know how it performs please. I am sure there are others who would be interested in the performance of a de-tuned RB250.

Martin

[carlos fandango]

Carlos,

That sounds like a very sensible idea. That might be a very wisely spent £140.

Let us know how it performs please. I am sure there are others who would be interested in the performance of a de-tuned RB250.

Martin

Will do

Its a 240, 60/110 alpha crank, 71mm, mb piston,jl3, 35tmx (which ill be changing to a 30mm) linner has been left 2mm higher than the gasket face and the head has been recessed to fit over it. Exhaust is 180 deg and trans 125 deg.