This happened a few days ago.
While I was riding I had shifted up to sixth, lifted the pedal again to verify I was in sixth (someone told me this is bad to do?) and noticed something felt different. It seemed as if there was way too much play.

I went up and down through the gears a couple times to see that they all functioned. I had only had the extra play in sixth.

Then over the following 15 minutes it completely took a dump.
The next time I pulled away from a stop light I couldn't get it past second.

I was already planning on rebuilding the clutch and have all new parts for that. Since this happened I picked up a used tranny on ebay, hopefully with everything I'd need.
eBay - New & used electronics, cars, apparel, collectibles, sporting goods & more at low prices

Any idea what went out? Any advice? I've never done this before.

 

Maybe a bent shift fork. Won't know till you tear into it. That's just a wild guess though.

 

Check your clutch cable before you get too deep. Be sure it's not frayed/stretched
and not fully engaging the clutch. Tapping up in sixth shouldn't cause any issues,
that I'm aware of. The suddenness of the issue, makes me think clutch cable as
a potential candidate.

Hope this helps, Ern

 

Doesn't sound like a bad clutch cable since you're able to shift to 2 gear. More than likely a bent fork ear. If that the case you have to split the case. Not a hard job to do.

 

Thanks for the replies.

The clutch cable is relatively new.
I took off the clutch cover and was going to replace the plates/springs, but I wasn't able to get the nut off to remove the basket. It had already been re-used and seemed crazy over-torqued.

I'm hoping I'll be able to start working on it in the next week or two.

 

It's really hard to get off if you don't use a impact wrench. Just a heads up.