Drivetrain clunk when accelerating out of first

Hello everybody.
I have just come across this topic. This is very revelant to me. I think the thread has drifted away from the initial question. The problem was that, when the thread starter already had his bike in first gear and as he left the clutch out and began to accelerate away there was a clunk. This clunk could be avoided by leaving the clutch out gently and accelerate gently. It is not the sound the gearbox makes as the bike is being put into gear. I have the exact same problem and after checking the final drive , and finding no problems, I am thinking that it may be the clutch. I have had this problem with some time. Today it has become more serious. There is a crack or clunk coming from the engine region when I start the bike from cold. It makes this sound maybe 6 or 7 times until it heats up. Maybe 10 seconds between each noise. Then it goes away. This has only just happened, so I'm thinking it may be linked to the previous problem. Any ideas?

I think I solved my problem - emphasis on not certain yet. Swapped out the final drive with one I bought on ebay. A 10 mile ride this winter - no clunk. Real test in the coming weeks. Have not taken the original FD apart yet for a PM. That ebay purchase was only 110 w/ shipping. So far, this clunk has cost me a bundle (I did not do all the work myself).

BTW, as my threads say, the second mechanic who worked on my bike used his head and a stethoscope to localize the sound. I heartily recommend this diagnostic tool for everyone - the dealer's guy simply test rode the bike and did his investigating with his ears far far away from the noise.
 
I think I solved my problem - emphasis on not certain yet. Swapped out the final drive with one I bought on ebay. A 10 mile ride this winter - no clunk. Real test in the coming weeks. Have not taken the original FD apart yet for a PM. That ebay purchase was only 110 w/ shipping. So far, this clunk has cost me a bundle (I did not do all the work myself).

BTW, as my threads say, the second mechanic who worked on my bike used his head and a stethoscope to localize the sound. I heartily recommend this diagnostic tool for everyone - the dealer's guy simply test rode the bike and did his investigating with his ears far far away from the noise.

It will be interesting to hear if replacing the final drive cures this problem long term. If it seems ok after 10 miles , it's probably sorted. Please let us know. I will source a final drive myself if it works out well for you.
 
I felt a clunk when the engine was hot and I accelerated away from a stop. This persisted for two years. Then the clutch started to slip when dropping to fourth and cranking to wide open throttle. I changed the friction plates and springs even though they were about the mid range of the specified dimensions. Voila! No more slip. No more clunk! Shifts much better as well.
 
It will be interesting to hear if replacing the final drive cures this problem long term. If it seems ok after 10 miles , it's probably sorted. Please let us know. I will source a final drive myself if it works out well for you.

Now a year later and a few thousand miles. Yes, replacing the final drive with my $100 used one from fleabay solved the problem. Completely. I've been meaning to take the old one apart and check clearances but one thing or another always seems more important.
 
Now a year later and a few thousand miles. Yes, replacing the final drive with my $100 used one from fleabay solved the problem. Completely. I've been meaning to take the old one apart and check clearances but one thing or another always seems more important.

Wow I’m glad to see this thread moving forward! Clutch sorta makes sense to me as mine sat for 10 years and maybe they dried out? I’m glad the fleabay unit solved your problem. I can’t believe my rear end would be cooked after 40k? Legendary Honda? Could also be the ujoint! Please read this as this guy had the clunk too. http://www.st-riders.net/index.php?action=recent;start=80

I’ve been stewing on this for years. I don’t think it’s cushions or slave now. Sounds like we’ve got it down to clutches or the whole rear end. Maybe they addressed something when swapping ?
 
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I can’t believe my rear end would be cooked after 40k? Legendary Honda? Maybe they addressed something when swapping ?

Nothing was addressed when swapping. I tried various things in order and tested after each one. The conclusive evidence was the noise localized to the final drive w a stethoscope. And, as fixes, it was cheap - the fd cost $100 on ebay.

Yeah, when I brought my Econoline in for service, they couldn't believe the steering box was bad, either, "These things NEVER go bad" the service manager said. Of course it had died a few months out of warranty. My 2010 1300 final drive began its demise (audibly, at least) around 26K miles. I suggest you read my earlier posts: Linky LinkyA LinkyB LinkyC

 
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I have this problem exactly!!!! Driving me crazy. I’m leaning towards clutch. It’s hard as hell to squeeze the lever and I get randomly good shifts and bad. Do I really have to rebuild the rear end ???
 
Fire, the two assemblies need to be investigated separately. Put your bike on the center stand and in first gear. Spin the rear wheel forward and backward and be aware of noises and where they come from...inside the drive unit or along the driveshaft (runs through the right swing arm tube. If could be the rubber hub dampers, drive splines, u-joint or driveshaft splines. Note the motion your wheel makes between the forward most stopping point and rearmost stopping point. If your wheel rotates more that 2" in either direction, you have something worn in that drive system, even if it doesn't 'clunk'. Change out the clutch fluid and note the color. Anything but honey and you may have a master cylinder or slave cylinder problem it it's been over two years since you flushed the fluids. Before you rebuild anything, do the flush with new fluid and give the bike a ride. Let us know what you find.
 
Sage Advice. The rear wheel play checked out ok. About 1 3/4 play. Slight “engagement” at the end of the spectrum. No noise, nice and quiet.
Definitely a warm/cold thing. It’s butter in the morning. I’m going to bleed the hell out of the slave next. Btw, new cushions and inserts.
 
It’s hard as hell to squeeze the lever

I would suspect the brass bushing inside the clutch lever is just about worn through by the m/c push rod. Take off the lever and look at that bushing. It is a wear item.

Side note to Joe - if he sees it - why is it a three step process now to get a quote into a post?? AAAARGGHHHH!
 
Side note to Joe - if he sees it - why is it a three step process now to get a quote into a post?? AAAARGGHHHH!
What are you talking about.. it's basically the same as before... use reply, not +Quote
 
use reply, not +Quote

OK, that DOES work, but it isn't like before, when you highlighted only part of a poster's text and got the "quote" word, which when clicked on, put the quoted text into my post. I was going with the old method, which now, does take more steps to get it into a post. Thanks.
 
OK, that DOES work, but it isn't like before, when you highlighted only part of a poster's text and got the "quote" word, which when clicked on, put the quoted text into my post. I was going with the old method, which does take more steps to get it into a post. Thanks.
Nope.. same number of steps.. but it gives you 2 things to click on .. +quote or reply.. still same number of steps you just have to remember quote doesn't mean here what it meant in the last one... here just use reply.
 
You're reading 'quote' but it's '+quote' with the + sign which means multi quote... here, I'll multi quote several words in above from you ..


OK, gotcha now! It's all these different little quirks in the presentation that need to be learned. Thanks again.
 
Yeah, I'm not sure how many actually use the multi quote.. it was on the other board but hard to use and here it's easier which means it's easier to confuse w/reply.. I may even deactivate it at some point if I don't see anyone using it.
 
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