300EX will not engage 1st gear

[Bandit65]

NOOB! My first quad I've owned.
I bought this quad a month or so ago, PO said a friend had rebuilt the top end and couldn't get it to run. The cam was installed 180 degrees off. I've been riding it around the yard and in surrounding fields with no major problems ( it does creep in gear with the clutch pulled in). But I took it for a ride at a local ATV park last weekend and it ran great the first ride. We stopped at the trucks for a break and when I restarted it for the second ride I dropped it in reverse and backed away from the truck, pulled it out of reverse and into nuetral and first gear will not engage. It doesn't grind or anything, like nothing is there. It does go in all the other gears (2nd thru 5th), however the rev limiter kicks in at a really low rpm. Anything cruising over 1/4 throttle and it hits the limiter. I'm assuming it's the limiter that kicks in when in reverse gear. I've pulled both side covers and I don't see anything that jumps out at me being a problem.

Anyone have an idea of the problem?
Thanks in advance.

[fmftrx300ex]

sounds like your quad still thinks its in reverse i would try puting it in and out of reverse a few times to see it will "fix" what ever got stuck posibly the reverse sensor or something in the transmition is just alittle off and causing the issue

[Bandit65]

Tried going in reverse and back out many, many times. No luck. I have a spare engine that needs some work (top end and crank rebuild), Once I get that one put back together I'll pull the cases on this engine. It has a hole where the chain has came off at some point. The PO "fixed" the hole with JB weld or something simular. Didn't see the "repair" till I pulled the cover, but it's cracking and falling in on the shift shaft, don't know if that's the 1st gear problem or not but I can't stand to know it's like that. So I'll pull it apart and tig in a repair patch.