yamiman
New member
how do i measure the rollers on my viper? i bought the sled used and had problems with my sled pulling rpm and ive done everything possible. on hardpack it will pull 8500 but in deeper but lighter powder it will only pull 7800-8100 rmp. i bought this sled used with a 141" kit on it since then i made it into a 136 with a 1.25" track. all the clutching is stock, now i have my doubts with the rollers. this is all at sea level
The rollers are marked or unmarked. Yours should be 14.5 mm which is the smallest roller Yamaha makes. It has a groove on one side & slightly machined edge on the other side. The problem you are experiencing is lack of backshift cus your sled is clutched on the edge. Lightening up the primary by a gram or 2 in the inner hole should fix ya right up.You could also go to a stiffer primary spring but lightening up the weights would be the proper way to get some backshift.You also might have a wicked steep helix also which can do the same thing.
yamiman
New member
alright thanks turk. my helix is a straight 45 
A helix about a 48/40 ish would help a lot if you are using a 45.
yamiman
New member
sorry about that its a straight 47