KR-1S.co.uk Forum

Have you checked the size fit of the pistons? might be piston slap??? although you would probably see excessive wear which there isn't.

I would check everything you disturbed when changing the pistons last, in case some thing is loose or re assembled incorrectly like a power valve?

You could check the weight of the pistons also?!

Have you shimmed up the lower engine mount where it's cracking? they are some times a loose fit which puts tension on the frame when tightened.

Haben Sie die Größe passte der Kolben überprüft? könnte Kolbenschlag sein ??? obwohl Sie wahrscheinlich sehen, übermäßigen Verschleiß, die gibt es nicht.

Ich würde alles, was Sie beim Wechsel der Kolben letzten gestört, falls irgendeine Sache ist lose oder nicht richtig wieder wie ein Stromventil montiert überprüfen?

Man konnte das Gewicht der Kolben auch überprüfen ?!

Haben Sie den unteren Motorhalterung unterlegt, wo es Risse? sie sind manchmal ein lockerer Passform, die Spannung auf den Rahmen setzt, wenn angezogen.

I have measured the crankshaft.
On the flywheel side (approximately in the middle) is the crankshaft 0.18 mm out of round.
how can this happen?

cheers
Dirk

No idea, but at least you've confirmed where I suspected the problem would be and you can move forward and get it sorted.

Good luck

Hapened to me 1 time with a engine

this engine was never opened before and the flywheel side was 0,4 off.

but it only vibrated when i was in lower speeds.

cheers Jarno,

good morning

Things stand:
answer from Mitaka.
they have looked at the piston and they say the pin has not moved out more that it was made that way IE close to the surface of the piston.

important!:
One thing they are recommending is not to fit the expander ring in the lower piston ring grove as they have had issues with this part breaking up in use.

i got new pistons.
thanks to PJ Motorcycle Engineers

greetings
Dirk

I have installed a new crankshaft.
the vibrations have become much less.
In any case the engine vibrates less than the RGV engine from a friend.

cheers
Dirk