Scooterotica

At mo running in stage 4 200cc engine done aprox 180miles,now i want to change to a asso piston,will i have to measure the barrel or just get the standard is it 66mm and carry on running it in.

thanks Paul

THE INDIAN BARRELS HAVE SEVERAL 66MM PISTON SOME ARE BIGGER THAN OTHERS THIS MIGHT HELP
66mm MAHLE piston. STD 3-ring piston assembly. FOR STAGE 4 SIL ENGINES. Please state (-), (0), (+), (++)
the above signs are for undersize and oversize pistons of 66mm diameter so its not a straight forward swap you need to measure and check if its to tight you risk seizure and if to loose piston slap and possible fracture of the piston skirt
even 2 pistons of the same make and size are not always equal

TBH you may be better off getting a good quality 2 ring 70mm piston and then getting your barrel re-bored and a honed to 3 thou. Somebody like Mick Abbey would be able to do this and also make sure all the are ports cleaned up and angled correctly for sensible money.

thanks all,i`m out this weekend putting more miles on it ,might wait till i`ve run it in then might get it sorted for a fast tour set up as i`m mainly on one`s own,but still reliable

paul

theres not much wrong with the mahle piston if the clearance is ok ive run one with a 30mm carb and pm 25 pipe and it was very good of the line top speed wise maybe 70 down hill on a good day
the thing that lets it down is the rings cant take high rpm if your gonna get a new piston and rebore these barrels make very good 225 conversions with alot of torque so the gearing can be upped as well you really need to decide what you want out of your scooter .... if it were me id strip it match the barrel to the casings match all the ports and inlet and outlet then chamfere the ports and run it with 1.2mm squish on the standard carb and what ever big bore pipe you have

thanks shocky 4 that hope to av it run in for crissey then the BIG DIS on which way to go

if you do it to 3 thou your gonna have to like running it in carefully even with a jap piston.
4 thou is what i normally do with an iron barrel, then thrash it

Definitely use 4 thou or it'll be prone to seizing for ages. I used a mahle piston with TS1 rings.

Tosh wrote:might wait till i`ve run it in then might get it sorted for a fast tour set up as i`m mainly on one`s own,but still reliable paul

You do realize that you will have to run it in again with a new piston don't you, maybe not for the full 100 miles but more 30mph for sure

Special X wrote:Definitely use 4 thou or it'll be prone to seizing for ages. I used a mahle piston with TS1 rings.

i think he prob has the 3 fat ring piston so would the ts1 rings fit