Questionok, maybe this will help. I sprayed a lot of wd-40 on the chain and in the clutch housing and it worked again for a second. The chain looks fine, not too much slack. I don't have a center stand so I can't do everything you said to do. I can change gears when the motor is off with no problem. I tried to ride it out in 2nd but unsuccessful. When I had the bike worked on, it was because of this same problem, but I thought the clutch needed adjustment so I tried to do this myself and it got so off that I needed the guy to readjust it. He said that he had lubed the chain a lot and that's probably why it worked fine when I got it back. He also said that the front brake was sticking, and I fixed this after I got it back. I assumed that the reason I was unable to ride it out in first gear was due to the sticky brake after I was told that the brake was sticking, but now I realize this is not the case. Sorry if this message is confusing. Hopefully you can help me out. Thanks again.
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I have a '72 cb500 four. I am unable to get it out of first gear. No one seems to understand what I'm talking about when I try to describe the problem. Basically, the engine stalls out when you let the clutch out or it jolts forward a few times and then stalls out. It's not an error on my part, although I know that's what it sounds like. There is no way to make a smooth transition out of first. There's no friction zone. I had it worked on recently and was told I need a new drive chain. Could that have anything to do with it? Also, the bike was working perfectly, then I left it sitting for about three weeks and now it doesn't work. I haven't made any adjustments and this is why I'm so perplexed. Please let me know if you have any advice. Thanks.
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Logan, that's a weird one, but I'm not exactly sure about what you are describing either...
1. Is the bike locked in 1st gear and won't return to neutral?
2. Can the transmission be shifted with the engine off?
3. Does it do this if the bike was on the centerstand and the rear wheel off the ground?
4. How much free play is there in the center of the drive chain? Is the chain skipping over the sprocket teeth due to excessive slack?
5. Are the sprockets worn down so that the teeth are not engaging?
"I had it worked on recently".... What did they do?
Possibilities are many:
The guy who worked on it made some errors or broke something or misadjusted something.
There was a factory update kit for the shifting mechanism for the early CB500s, because they had awful shift problems. If yours is still as it came from the factory, something may have worn/broken or is otherwise not functioning correctly.
If the drive sprockets are worn down, the chain will skip over the teeth. Same thing happens with too loose of a chain.
Put the bike on the centerstand. Try to shift the transmission through the gears, either running or not.. or try both. If it won't shift out of 1st gear, then the clutch has to come off and the shift mechanism inspected.
It may be trying to select two gears at once or something has broken internally, which is fairly unlikely, in most cases with these bikes.
If the transmission shifts in a no load condition, then the clutch assembly maybe at fault. Be sure that the clutch cable is adjusted correctly and isn't failing internally.
Can you select 2nd gear and have it move forward on its own?
You can see that there are more questions than answers here, given the variables that I don't have answers to, at this time.
Hopefully you have some more things to check and consider with this problem. I can't really answer more here w/o a more detailed message of what has been done, not done and what all the symptoms are under various scenarios...
Bill Silver
AnswerLogan, you need to roll the bike forward a little at a time to see if the chain is suddenly getting WAY too tight, due to damaged links. Mark the chain and then check the chain slack every few inches, until you have checked the whole length of it. Normal chain slack is about 1/2 to 3/4" at the "tightest" point of the chain. If setting the slack there results in 1-2 inches of chain slack at other rotation points then get a new chain NOW!
Certainly a stuck brake caliper will cause the bike to slow/stall out, but you claim you have fixed that... ?
Pull the front chain sprocket cover off so you can see what is happening there. You need to inspect the drive sprocket for damaged teeth. The shift shaft runs through the left side cover and should be checked for wear/damage due to loose chain or from a crash.
These symptoms are pretty hard to understand as you described. If everything looks okay under the left side cover, then I think you better pull the clutch cover and take a look at the clutch plates/springs.
Bill Silver
