AR80 revs high on cold starting

AR80 kawa · L Plate Warrior Joined: 14 Apr 2009 Karma :

Hi all,
Hope you can help with this

My AR80 revs upto 7000 rpm (sometimes more) when I start it from cold

The revs drop down gradually over a minute or so and then it ticks over very well. If left ticking over for a while say 5 mins or so it does eventually stop, but starts ok and ticksover again.

It runs well and does around 60ish mph

I have tried the following to cure this fault
New crank seals and bearings - they were worn
New big bore 93cc kit - original bore was worn
New CDi
different air filter
New seal between carb and inlet manifold
Carb has standard 80 jets
DTI set the timing - the original was slightly out but made no difference

The exhaust is a Ginelli system and has been on the bike since i bought it so i don't know if it is that as i don't have another to try

any ideas please
cheers

finpos · World Chat Champion Joined: 13 Sep 2005 Karma :

Sounds more or less as expected to me, it's not got an automatic choke, has it?

f.

AR80 kawa · L Plate Warrior Joined: 14 Apr 2009 Karma :

it is a manual choke
I have had many 2 strokes and have never had one that revs this high when cold

finpos · World Chat Champion Joined: 13 Sep 2005 Karma :

Assuming then it's doing this with the choke off, have you tried running it on premix with the oil feed (presuming it has one...) blocked off?

f.

AR80 kawa · L Plate Warrior Joined: 14 Apr 2009 Karma :

no i haven't tried that but I will now you have suggested it
thanks