Re: My chain is saggy
Way too loose.
You'll want 1/2 to 3/4" slack in the upper chain run measured by engaging the clutch and rolling the bike forward just enough to tighten the upper chain run.
You should be able to get that much adjustment by raising the tensioner wheel just a little.
Chain tension and alignment are very important for a reliable drive system.
Tighten that chain and check for straight line alignment between the engine drive sprocket and the rear wheel driven sprocket. The tensioner wheel also must align with the chain path. Sometimes that means bending, or twisting the tensioner bracket so the wheel is aligned with the chain.
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