Re: Thanks for the help so far!
With the engine drive chain installed and clutch properly adjusted there will still be some parasitic drag when pedaling with the clutch disengaged. A chain that is too tight or lack of lubrication can also contribute to that drag.
You don't want the tensioner on the top chain run. The chain is already tensioned when the engine is driving the bike. It is the bottom chain that goes slack and needs the tensioner.
Have you tried shortening the chain and running without a tensioner? Some frames will allow this and you'll be happier without the tensioner. Keep your chain tension at 1/2" to 3/4" slack measured on the top chain run as you gently roll the bike forward with the clutch engaged. As the piston comes into a compression stroke the top chain will go slack. That's where you want that 1/2 to 3/4" measurement.
If you are using a good air cooled 2 stroke oil follow the manufacturer's mix ratio recommendations. We usually suggest anywhere from 24:1 to 32:1 as a good ball-park mix ratio.
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