Can't shift into first now when cold

[Joel750T]

This is weird, before I take it back to the mechanic, looking for thoughts.

Only happens when the bike is cold and has sat for more than a day does this happen. 1982 GS750T

I start the bike, let it run for 1-2 minutes.
Pull the clutch, shift into first, the bike instantly lurches and stalls. Same thing in second. Clutch clearly not disengaging.

Let it warm up a few more minutes, do it again, 50/50 chance it happens again. Once it engages, it's a little sticky shifting between first and second for the first mile or so, then it is nice and smooth after that.

There was old and low oil in the bike when I got it and I had the sticky condition from first to second, but not the problem getting into first. I changed the oil saturday morning (if anything, it is a bit overfull at the moment) and had the first problem with getting into first sunday afternoon before a 150 mile ride. Commuted in on it this morning and the same behavior.

No idea what kind of oil was in it before (other than the very black kind), but I only got about 3 qts out and 4 qts of Yamalube 10w-40 and a new filter went in. Next change is going to be the Rotella 15W-40 when I know the mornings are going to be out of the 30's to see how that does.

So questions are this. Any ideas why this is happening? Am I going to destroy the clutch/transmission if it keeps up?

Thanks.

 

[tkent02]

This is weird, before I take it back to the mechanic, looking for thoughts.

That part is scary. Mechanic? If you need a mechanic get a newer bike.
Is the clutch adjusted correctly?
Does it work fine once it's warmed up?
Clutches can stick like that for a variety of reasons, could be warped plates, a worn basket, too heavy springs, other causes. Some of them just stick, roll forward down a little slope or something before you put it in gear start out the first time and don't worry about it. Could be oil related, don't think just a little too full would do it although that is not good for the rest of the engine. Pop the cover off the clutch and see what's up with it.

 

[Joel750T]

Thanks. Bought the bike on consignment through a mechanic who works out of his house only on old japanese bikes and said he would stand behind the bike. I have 8 days of experience with motorcycles at the moment so any outside input would be helpful. The plan is to become self sufficient, but clearly not there yet.

Yes, bike shifts perfectly fine after it is warmed up. Clutch starts engaging about 1/2 way out, maybe a touch earlier. Had it up to 75 then went up a steep hill watching tach and no slip.

 

[tkent02]

Well maybe he will fix the clutch, if you are lucky. It's not that it doesn't work, it just sticks.
If he fixes it watch him work if you can, you will get some idea if you want him to work on anything else. But really you are better off getting in there and learning it yourself. Clutches on these old bikes are quite simple.

 

[Guest]

Have at least 2mm play at the clutch lever.

 

[Joel750T]

Chef, which way? From the grip when releasing, or from the start of the squeeze? I get about half way out on the release before rpm's start to drop at all when at idle (this problem aside). When squeezing, it starts to slip after about 1/4-1/2 inch or so when downshifting.

 

[gearhead13]

Mine used to act that way when i ran 20w50(heavy oil) in it.

 

[kdo58]

you need to read, basscliffs website which will tell you most everything you need to know. It is geared for gs850, but the same basic principle applys to your bike.
http://members.dslextreme.com/users/bikecliff/

 

[SqDancerLynn1]

When the oil is cold and thick it will cause the problem. IT doesn't necessarily mean anything is wrong. Just warm it up and make sure the idle is set around 1K -1200 rpm. I usually work the clutch a few times as it warms up before putting it into gear..

 

[Guest]

2mm play on the lever when starting the pull.

 

[Dave8338]

From what you're describing, it does sound like it is out of adjustment. Use both ends of the clutch cable adjustment to get it right.

 

[legaleli]

you need to read, basscliffs website which will tell you most everything you need to know. It is geared for gs850, but the same basic principle applys to your bike.
http://members.dslextreme.com/users/bikecliff/

Basscliff's site is awesome. :clap:

 

[Joel750T]

BassCliff's site IS awesome Now if I can retain 10% of what I have been reading the last month....

Just wanted to post an update. Letting it idle a bit longer on cold startups and giving a couple squeezes to the clutch cable as it does, along with having the oil level just right seems to have eliminated the problem getting into first. Second still tricky first time in, but after a lap around the neighborhood it's good to go.

Thanks to all for the help.