Jesse Peterson
New member
I have a 2004 viper mountain and I am wondering if radius rods from an 03 mountain will fit on my sled. Yamaha has different part numbers but I would think they would be the same. Also wondering if rods from the left or right side make a difference. Yamaha has the same part numbers for left and right for my 04.
same parts and same part numbers. different for upper and lower. no difference left or right. mtn viper parts start with 8EN. most likely you read the parts wrong and saw an 8EK for the short vipers.
This is correct. The arms are the same for all years Mtn Vipers, but the diagram (used to call it microfiche) had both the 121 Viper and the Mtn Viper on the same slide in 2003. Led to a lot of confusion. 8EN is the Mtn like mentioned above. So as long as you can find Mtn Viper arms, all you need to know is upper or lower.
Thus, there are only 2 part numbers for all radius arms on a Mtn Viper (any year). Upper or Lower.
There is an angle on the fixed ends, you just mount them opposite between sides. Also heim joints go on the outside for upper, and inside for lower. Had a Yamaha tech guy once explain that this was to allow the arc of the T-arm to swing freely, but I always thought it should be heims on both ends.
Jesse Peterson
New member
Yea the yamaha website is showing 8EK for the 2003 mountain. Thanks for the help guys