Join Date: Dec 2009
Location: central mississippi 39180
well sounds like you need to open it up and do some investigating. i still dont have enough info to accurately pinpoint the problem. do you have the mechanical ability to take your clutch housing off and inspect the clutches? nd have a caliper to measure the belts width with? it sounds like your belt could be worn out below specs, or your shoes on the secondary under the helix could be worn out not allowing the secondary to completely close all the way allowing the belt to be loose and slip. there are only a few reason a belt would slip and one is that the belt is worn below specs (usually takes about 2,000 miles) and another is the secondary not closing up tensioning the belt properly, also the primary could be sticking open. it is more rare to see but it does happen. the primary has felt bushings in it that allows the outter half of the primary to slide back and forth on the sleeve in the primary, if those bushings get wet they swell up just like wet cardboard and then make the primary sieze up. that would keep the primary from closing up properly allowing the belt to slip, but not likely only do it in forward and not reverse.
let me ask you this: how do you know it is the belt slipping? can you hear it audibly and smell belt smoke? or is the bike just rev'ing up and not going anywhere? the whole "in forward only" thing has me a little puzzled.