Yamaha Tri Z 1985 Misses high RPM no 3rd gear Problems. HELP

[Faster32]

Just bought a 1985 Yamaha Tri Z.

Starts good and revs good when first started when you hit the throttle and release quick. After running 3 minutes it misses at high RPM. Hold the throttle down and it misses. When you drive it and are not in the powerband runs good but as soon as you get near the powerband it misses. Seems like not getting spark or running rich? Any ideas?

Also I believe it is a 6 speed? Eveytime it shifts to 3rd it is out of gear. Shift up again and it catches the next gear. So I either have no 3rd gear if it is a 6 speed OR you have to double shift with the foot shifter to get in 3rd if it is a 5 speed.

[tecat-z]

Shift forks and engagement dogs are shot. They go together. Your choices are to send trans to get cut, or replace Many pieces in the trans with suitable used items. So many of these poor old trannys are slippin' now.

[Bryan Raffa]

whats the vin on the cases behind the kickstart? sounds like 3rd is gone... and it sounds like its not jetted

[Faster32]

The engine S/N is 38W-000583