My k3 600 50k miles has an issue where under hard acceleration it will almost have a skip, tug feeling or stepped acceleration. It seemed to happen in first once or twice if I remember correctly but only seems to really do it after 10k in 2nd. It will feel like it skips 2-3 times from 10k to redline. It almost feels like its missing a tooth on the front sprocket. The RPMS don't jump up much like it's really slipping. It doesn't make a horrible sound. It feels like someone is almost grabbing my back tire for a second and then letting go. It never goes into neutral; it stays in gear in the whole time from what I can tell. I can hit redline no problem in 2nd if I don't accelerate hard. I just replaced the rear bearings and did a chain and sprocket kit as they were both worn. I added new rubber to the cush drive. It's never done it in any gear above 2nd. I have a power commander and I tried a different tune. Curious if anyone has a had this issue? Sounds like the trans could be the issue from other posts. Curious if the clutch ever throws symptoms like this as that would be the least expensive to change out. Thank you for your time.