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Discussion Starter #1
Hi everyone,
I'm new to this forum. I've been riding my 2000 VStar 650 Classic for almost five yrs back and forth to work logging 20,000 miles on a bike that had 12,000 when purchased.Last week coming home I noticed a single clunking sound when I would back off the throttle when slowing for a traffic light. It started off just noticeable and ended up being a LOUD clunk before entering my driveway.
Next day I put the bike on a stand with the rear wheel off the ground and rotated the rear wheel back and forth to see if I could replicate the clunking sound. I could not feel any type of play in the universal joint or make any sounds. I started the bike and shifted into fifth gear and let it run. It made clunking sounds (while idiling in gear) coming from the lower end (similar to something being rather loose in the crankcase. I shut it down, drained the oil and removed the crankcase cover fully expecting to find something very loose inside. I also removed the cover for the middle drive pinion gears for a looksee. Upon inspection I could not locate anything loose so I removed the entire clutch assembly. With the clutch housing removed I rotated the transmission mainshaft back and forth and could definitely replicate a clunking sound when the tranny is in gear. Should I be able to rotate the mainshaft back and forth approximately 30 degrees+ before the shaft engages solid? Seems like an awful lot of play. Just trying to figure this all out.
Thanks for any and all help.
 

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The tranny gears slide on a spline and there defenitely should not be 30 degrees between "clunks" in the spline, nor is there 30 degrees of backlash between meshed gears. However there is a loose fit of the dogs on the side of the sliding gears that engage into the side of the fixed gears....but 30 degrees still seems excessive, but then again there just might be more distance between "clunks" in 1st as compared to 5th.
 

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Discussion Starter #3 (Edited)
The tranny gears slide on a spline and there defenitely should not be 30 degrees between "clunks" in the spline, nor is there 30 degrees of backlash between meshed gears. However there is a loose fit of the dogs on the side of the sliding gears that engage into the side of the fixed gears....but 30 degrees still seems excessive, but then again there just might be more distance between "clunks" in 1st as compared to 5th.
stratowart,
I can feel a difference in the amount of slop by going thru the gears. It still seems excessive in all the gears though. This problem seems to have reared it's ugly head all at once versus something that I noticed and got gradually worse. The bike has run perfect. The only thing that comes to mind is that over the past couple of months (this only happened maybe three times) when I was getting ready to up shift the bike would jump into the next gear before I hardly depressed the clutch lever. Kind of like speed shifting without trying. I wrote it off as sloppy shifting on my part.
 

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Its hard to say you can't jack the back half up and test these bikes aren't built to very tight tolerances and besides your not going to replicate the same force you would under a load. if you shift early you can get some clunking coming from the crankcase area. I know you checked for play but have you serviced the differential?

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I wish I knew where to go look to find out what is an acceptable amount of slop between the two tranny shafts but I don't. I can tell you, even tho I don't have a shaft drive scoot, that I will get a very audible "clunk" when dropping it into 1st at a dead stop. I've always attributed that to the loose fit of the dogs on the sides of the gears. Elevate my rear tire, put it in any gear and I can rotate the back wheel several degrees CW and CCW and get a "clunk" as well. I'm not sure if you are going to pull out the tranny shafts and inspect the gears but I wouldn't blame you if you didn't because I can't imagine the dogs to wear out "overnight" like you just experienced. And being a drive shaft bike you already did the most logical check which is the universal joints (it was my first guess until I read your entire post at the top of your thread).
 

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Discussion Starter #6
I know you checked for play but have you serviced the differential?
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SSC,
If by differential you mean the middle drive and middle driven pinion gears I have removed the access cover and inspected them for any wear or play. They seem fine to me.

stratowart,
I'm trying to avoid splitting the crankcase in two if I'm not 100% sure that's where the problem lies. I'm going to spend some more time going over it to see what else I can come up with.

Thanks,
Gary
 

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I agree, unless you see good size bits of steel in your drained crankcase oil I would NOT crack the engine cases open either. But I would at least check your drained oil for stuff that shouldn't be there. I hope it ain't too late to check it..
 

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Discussion Starter #8
I agree, unless you see good size bits of steel in your drained crankcase oil I would NOT crack the engine cases open either. But I would at least check your drained oil for stuff that shouldn't be there. I hope it ain't too late to check it..
That was my next thought was to filter the drained oil and see what shows up.
 

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Discussion Starter #9
Well gentlemen I may have located the culprit. While the crankcase oil was straining I decided to take a better look at the universal joint. While manually turning the drive shaft back and forth by hand to see if I could detect play in the UJ I felt the drive shaft freewheel in the final about 5-10 degrees. This action when done forcefully generated a loud clunk from the final. I remember the first couple times I heard it the noise sounded like it came from behind me and I wasn't even sure it came from the bike. The last time it occured as I was approaching my driveway and a LOUD clunk came from under and slightly behind to my left which would be in that area. So, I drained the final and what came out looked like metalflaked gear oil. Not large chunks but enough to make the oil look kind of milky when it was draining.
The strained crankcase oil showed just a tiny bit of metalflaking. My Clymer repair manual says take the final to a qualified repair center as it takes special tools and knowledge to repair.
Thoughts?
 

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Only because I've heard shaft drive repairs get pricey, my thoughts are filled with sympathy. Thinking the final is mainly a small spiral bevel pinion on the end of the driveshaft that churns against a large spiral bevel gear in the wheel hub tells me one or both have gaulled faces on the gear teeth. I can't imagine what special tools would be needed. Wish I could be more help but I'm completely ignorant of shaft drive scoots.
 

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Discussion Starter #12
I needed to get the bike out of the middle of the garage as Tropical Storm Isaac is headed towards us and the wifey is not gonna be happy if her car has to sit outside during a tropical storm or worse yet a hurricane!
That said I decided to reassemble the bike somewhat and move it out of the way until I can pull the back wheel to check out the final drive. As I do not have a clutch holding tool to use while torquing the clutch nut I wedged the rear wheel against the bike frame and put the bike in gear. At 30# on the torque wrench the final drive jumped a tooth! Sure seems like that's my problem. Needless to say I'll be tearing down the final drive. I'll most likely replace it with a low mileage used one as the new one runs about $840 at the dealer. I sure appreciate all the help on here and I will update as I progress.
Thanks,
Gary
 

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Yeah the finial drive is the differential I speak car sorry to hear that. If you get a used one make sure to fill it with good synthetic oil. I service mine with royal purple just cause if tots a better anti shock package compared to other gear oils

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Discussion Starter #16
Update 8/26/12
After removing the rear wheel on the VStar I attempted to remove the final gear assembly which is just supposed to lift off the wheel. I had to use plastic wedges and when that did not work I went to steel wedges. After some careful manipulation with the wedges it finally seperated from the wheel. The output gear on the final drive is a spline which looked well worn to me but not enough to jump teeth. The opposing spline is in the clutch hub attached to the wheel. I removed that today and found that the splines are almost completely worn off. I'm attching pics.

Pic of output gear on final drive assembly:



Pics of the spline on clutch hub:





I'll be ordering new parts tommorrow and wanted to thank stratowart, SSC, and aide for there input in figuring out this problem. Thanks guys and this is a great forum! I'll update when I get it all put back together.
 

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Thanks for putting up the pictures Gary. I'm sure we will get a better appreciation of the extent of the worn out parts when we see pics of the new parts. Still sorry about the trouble your having, not a cheap fix.
 

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Discussion Starter #19
well we just discovered on my o8 raider with 17800 miles my 3rd gear broke a tooth and
has the same symtems described
Welder,
Sorry to hear about that 3rd gear. I ordered and recieved a used final drive from ebay. It seems to be in good condition with around 17500 miles on it. I'm waiting for the new clutch hub which should arrive in a day or two. Hopefully I won't have more problems such as you just described once I have it all back together. I'll update as I go.
Gary
 

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Had the same issue on my 03 1100. Out of the blue one day it just started clunking. After getting advice from a dealer friend of mine I removed the rear wheel and PRESTO! There it was. My wheel hub was worn down to barely anything, as yours shows. I'm sure this is due to lack of maintenance by previous owner and my scoot had 35,000 on it when I purchased it. Now has 38,000 and change. I replaced the wheel hub for about $90 bux. Lubed liberally with Honda Molylube 60 as instructed by many noteworthy forum users and no troubles since. By the looks of your final drive hub, you should easily be able to replace the wheel hub only without any issues or concerns. The final drive hub is a harder metal than the wheel hub, which is why the wheel hub wore much more than the final drive.
 
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