RK, EK, DID are all good chains.

 

Is 15/42 best gear ratio 4 racing a ds650?? N do u know wat I should do I can't adjust my chain no more I have it set on the tightest possition n its still 2 loose?? Should I just cut it??

 

On a stock bore DS I always found 15/42 to be the optimal gearing for my weight ~180lbs while out in the dunes. The bigger heavyweight guys tend to go even lower 14/40 while the big bore guys can go even taller than stock gearing. There are a lot of factors that go into determining the best gearing

-Rider weights
-Motor mods if any
-rear tire diameter
-what kind of racing are you talking about? Flat?, Hill?, 300ft, longer

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