I have someone asking me to help them with a single sided swing arm mod on thier 900. Of course the typical mod is a VFR swinger which I actually recomended against for him.

My thought is that swing arm is based on a 750/800cc bike with around 100hp or less and as manufacturers are continually beefing and bracing swing arms each year to handle the increase of performance,HP and torque, IMO, I can't imagine that swing arm being stiff enough to handle a 35-50% increase in horsepower and torque over which it was designed without a substantial increase in flex and other related forces. Not to mention handling, particularly when laid over at high speed.

In this application the bike is a 945 RR with around 140RRHP and the guy rides hard.

So my question is to those who have done this...what differences, if any, have you noticed by going to the weaker arm?

Thanks for your replys in advance.

 

I am waiting to see someone fit one from a Ducati....

 

none...



and i flog my bike hard...



i've seen heavily modded zx10 motors with a viffer arm that take it just well. it weights about 2x as much as the stock swinger on the 954. it's not weak by any means.

 

I want one on my F4i....but who can help meee!!!!!!!

 

I understand it to be as much as 18/20 lbs more than the stock swing arm. Did you happen to weigh yours?

 

i didn't.... but with test fitting and everything holding it way out in front of me, i'd say that'd be about right. it was awkward as hell to test fit - but i love the look, and you cannot tell any difference in performance.

i had to use a viffer dog bone, and then upside down triangle plates - and i still don't think it's just right. i know you have a shop and could machine your own triangle plates.


if he goes through with it, let me know what you and him think about triangle plates, and if you or him decide to make them, i'd love to get measurements or throw in on materials to get some made.

 

Sure thing.