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1978 750 5th gear not engaging on the street.

ridersup

ridersup
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My 78 750k (9500 mi). will engage all gears setting on the stand manually, engine not running. Put it on the street under load and no 5th gear engagement. There are no funny noises or vibrations. Goes to 4th gear and stops ,push as hard as you want ,goes no further. Any body experienced this? Thanks for any replies.
 
Sure you don't have that backwards? Generally it's pretty odd to be able to get all gears with bike on stand with zero rear wheel rolling or engine off as they are not synchronized and the gear side lugs get in the way of at least one and commonly the higher ones up.
 
Pushing would indicate going down on the shift lever...1st is down back up is neutral then 2 through 5 are up after neutral, 1N2 3 4 5. You sure you know where your gears are? Not trying to be a jerk or a smart ass its just some of the people that show up on here with some of the questions they ask...well you get the idea. We need to cover the basis and make sure you know how the gear arrangement is. And AMC is correct you can hardly ever get all the gears with it standing still. If you have been really pulling or pushing hard on the shift lever then you probably bent a shift fork or maybe broke one of the engagement pins off the fork. Anyway, basically any issue with the trans means you have to split the case to investigate. There is a slim chance that maybe a pin fell out of the shift drum under the left hand trans cover, if not you have to split it apart.
 
'You sure you know where your gears are?'

And X2...................I wondered the same thing but trying to be tactful. One of the gears you go down to get, all the others are up.
 
Backwards?

I have rear sets w/ the factory shifter shortened and turned 180 degrees . Hence one up -neutral- 4 down. I do not take offense, but appreciate any input. I have accurately counted the shifts up/down, as well as the readouts on the factory tach and speedo. Almost doubt my own sanity at this point. Removed trans cover for visual check-function.(with spinning the wheel manually while moving the shifter) Able to count sequence too. "My bike is the '78 cheap build in the gallery"... Will dissemble and check the pins as described first, go thru anything else (the 77 donor engine came from a crashed bike). I appreciate your sharing time and knowledge.
 
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Gimme 5

Gimme 5-gears that is.... Thanks to all for the advice. I failed to mention that on initial assembly of the engine ( gaskets/ seals) , that the shifter had resistance upon operation. Chalked it up to new seals. When ridden would not shift beyond 2nd gear. Doubled the trans cover gaskets/ reassembled, and went to 4th gear on the road. Listened to your comments about possible damage inside (bent stuff). Removed trans cover and removed about .010 from inside the cover where the shaft comes thru. Reassembled and now have all gears to 5th. Certainly not a recommended solution for anyone ( except maybe if your donor engine was crashed). Last ditch effort for mine, see how it pans out miles down the road. Again thanks to all.
 
Sounds to me like the shifter shaft is bent, they are cheap, easy to replace. Easily bent when tipped over or kicked into gear hard.
 
If bike crashed on the side of the shifter you can practically count on a bent fork...........sometimes a mod like that works wonders. Might wanna look at how the shifter linkage lines up in the shift drum too, could be shoved way over to one side.
 
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