I have two new YS61ST engines, and was wondering what the difference was between them and the newer YS61ST2.

Can the older engines be upgraded?

Thanks

Alex

http://www.rcuniverse.com/showthread...ighlight=ys+80]

Paul, I think you've answered the wrong question. The ST2 had a different carb with an adjustment for the idle mixture that wasn't present on the ST!, and the cylinder porting was somewhat different. I believe the ST2 had slightly longer exhaust timing, but I can't say for sure. The ST1's were excellent motors that have good power. The cost for the parts to change them to an ST2 is probably more than they are worth, you're better off to just use them as is. Steve.

Their the same engine just with a different barrel that's why it's named the st2.

You must be thinking of the 80. There were some other differences between the 61 ST1 and ST2. Steve.

You know what you're right , geez where is my head at. OK never mind what I said before. Thanks for setting me straight.