The Problem:
==========
The problem is not so much that the vibration from the engine that's causing your right throttle hand to go numb. The problem IS that the throttle return spring on my '10 S1K is much stiffer than any other bikes i've ridden (R1, GSX-Rs, CBR, ZX).
With the throttle spring being so heavy, your hand is forced to grip the throttle much tighter than normal just to keep the throttle open. This heavy spring, combined with the weight of your upper body resting on the clip-ons and the vibration from the motor, will cause your throttle hand to go numb pretty quickly. Prior to owning the S1K, i could ride my '10 r1 for all day without having my hand go numb. But on the S1K, i might only ride mere 30-50 miles before the numbness on my throttle hand would become annoying and sometimes unbearable on longer rides.
Personally, I don't think the S1K engine gives off any more vibration than my R1, but the fact that the throttle return spring is so stiff, it' makes your hand go numb much faster than on other bikes. If it was excessive vibration, your clutch hand would go numb as well on long rides, but that's not the case here--at least not for me.
The Solution
=========
I spent the better part of a day taking the S1K apart to get access to the throttle return spring on the throttle body, doing the modification and putting everything back. The throttle spring is preloaded about one full revolution from it's unsprung state. I fabricated/tig welded a bracket that allow me set the spring at a much lower preload than original--maybe a tad bit more than I needed. But now i can go on an all-day ride without my right hand going numb. However, there was a minor downside. It took me a few hundred miles to "unlearn" the heavy throttle grip that i got used to before the modification--it was bit hairy at first modulating the throttle on tight corners in low gear. But now, i can say, I actually enjoy riding this bike without any more compromises.
MrC
|