can a 90 go to a 70 with jug change

[vislaguy]

can a 90 go to a 70 by changing the jug and carb ???

[pitviperacing]

nope, a 50 & 70 use the same crank, 90's use a bigger crank. stock viper models use the same 18mm carb for the 50,70, &90 just differ jetting.
why you want to downsize??

[vislaguy]

my sons only 4 and at our track it doesnt matter they put all the minis together bt if he does any poits races it would be in a 70 class with 6 year olds.Its just for refrance after he has some time at our local track.

[pitviperacing]

ok, I'd seen your other post. thats the nice thing with the eton vipers 50 70 90 all same frame. I started my son on the 50 then put a 70 kit on it. I picked up a used 90 motor on ebay for when the time comes to move up.

[vislaguy]

i will keep my eye out for a used 70 then put back the 90 for later.