Got a 99 sundiro 90cc from my neighbor for my 6yr old son, had to clean the carb and fix some of the wiring and put a battery in it, didn't have high hopes for it as it's been sitting in his garage for 7+ years. Surprisingly it fired right up only issue i have is the wheels spin as soon as it's started. I'm guessing the clutch is stuck engaged, is there a way to adjust it? Or could it be something completely different?

 

If it is the 2 stroke Minarelli engine, the clutch is centrifugal, so won't be adjustable. Too long since I worked on one, but I think it is similar to the Suzuki LT80, attached to the driven pulley in the belt box, so fairly easy to get at. Because it depends on the speed the driven pulley is going, to engage/disengage, a fault with the belt pulleys can make the driven pulley go too fast at idle, so check that as well.

 

It is a two stroke has the oil tank under the seat. Not 100% sure of the engine but probably the one you mentioned. The adjustment for idle is on the carb correct?

 

Yes, there is an idle speed adjuster and a slow running mixture screw so, if you think the problem is the idle speed too fast, adjust the speed screw down to the slowest it will run without stalling. Most of those Minarelli engines have an electric choke, so need to be warm before adjusting. Also check the throttle cable adjuster. I worked on a Massey Ferguson (Arctic Cat) last week, once I got it running, revs were way up at idle, then I noticed someone had been adjusting the cable, no idea why.