quick 250r Question

[dizasterzrfun69]

I have an 84 R i bought off of a member awhile back and its been sitting in the garage. I finally got it running and just as he originally told me, it wont stay in 2nd gear. It will go into first and neutral good and drives in 1st no problem . It will also drive through 2nd gear and so on but i have to hold the shifter up with my foot if i go out of 1st. He said he thinks he left a spacer/shim out in the tranny somewhere. Could it be something simpler or is it most likely a missing shim some where in there? I really hate to have to pull the motor if i dont need to.

Kevin

[200x Basket]

either a shim or a bent shift fork