Strange clunk when engaging the clutch

[Vykk]

Hello, I am new here. I have been wanting a Vmax for a very long time and I finally bought one. Found a decent deal on a 2000 (12k miles) in town, picked it up last Thursday. Super excited and really fun to ride.

So, first off the clutch lever was very weak so last weekend I bled the clutch and reverse bled it to get all the air out. Very responsive now, probably need to adjust where it engages now. Since I was working in the garage I figured I’d change the oil as well. Picked up the KN-303 and some Rotella T4 15W-40 as I read on here that is a solid choice. Bike was running great around town the rest of the weekend, this Tuesday morning (today) I took it on the interstate to go to work, everything was fine. At lunch I wanted to go for a joyride and noticed that when I disengage the clutch I hear a clunk for the first time. Drove around the block and it seems that it only happens from a stop and maybe 2nd and 3rd, after that I can’t hear anything but the wind. Did some testing holding the brakes and cycled the clutch in the video below.



I’m thinking/hoping that it’s a minor fix like clutch plates, clutch lever position, wrong oil or too little (mid site glass on center stand) or low shaft fluid.

Anyone seen this before? Any guidance?

Thank you in advance,
Vykk

 

[Fire-medic]

Maybe a good idea to buy a clutch cover gasket & to see if anything is amiss in the clutch. I'd check the diaphragm spring bolts, the clutch hub nut and whether the clutch basket is worn.

It is not my experience that worn friction discs or 'steelies' cause a noise like you have.

For whatever reason, different oils can have different effects on the engine. Some people have reported Brand C causes it hard to locate neutral coming to a stop, others say Brand M results in harder shifting. Your choice of Shell Rotella has been used by many VMax owners with good results.

You had the bike in neutral, and you were just pulling-in the clutch, and then releasing it? The clunk came as you were pulling it in?

As to adjusting the clutch 'where it engages now,' being a hydraulic clutch, 'it is what it is.' I don't know of any possible way of adjusting it.

 

[Vykk]

Sorry, bike was in 1st gear, and I was just using the clutch for the gears to catch.

Also new to hydraulic clutches, wasn't sure if there was an adjustment on them or not, like a set screw.

 

[MaxMidnight]

If I'm reading you correctly this is a new noise that wasn't there before you changed the oil and bled the clutch?
Assuming that you didn't do anything else (?) then I can't think why either of the above would cause the noise.

As Mr Medic suggests, a look at the clutch would be the first thing to investigate.

Hydraulic clutches are self adjusting.

 

[Vykk]

Yup, changed the oil and bled the clutch. Ordered a new clutch gasket, so I will probably take the cover off tonight and take a look. Might order some Yamalube and see if that does anything different. That's what I used in my 82 XJ550 for years.

Side note question. Best place to order parts? I got the gasket from Partzilla. If I need new clutch friction plates is there a goto that the majority uses for parts or is Partzilla a good choice?

 

[Vykk]

Took the cover off. Everything looks pretty good. Bolt were tight, not stripped. Basket looks good. Plate and diaphragm looks good. This is all my opinion which could be incorrect. The friction plates measure about 2.99 mm on average.

I did a wiggle test… is this normal?

 

[Fire-medic]

The wiggle test doesn't appear to be the problem.
The clutch basket appears to be aligned properly, basket hub to friction discs. Image 3

 

[MaxMidnight]

Agree with Mr Medic that there isn't anything obviously wrong with the clutch assembly.
Now that you have the cover off can you tell which side of the engine the noise comes from when someone operates the clutch lever? i.e. Clutch or slave cylinder?
When watching the plates disengage is the operation smooth or is there a jerk?
Have you checked the clutch push rod?

 

[Vykk]

I pulled the clutch a few times with the cover off and everything still attached. Seemed pretty smooth, not hard to pull, no jerking.

I have not checked the push rod. I did have to push it in a tad when reassembling after checking the plates. Should that be pushed in all the way in reassembly, or should it be out a bit like it was?

It did look a bit like the picture in this post from Scaryguy
https://www.vmaxforum.net/threads/clutch-problem-vmax-1200-1992.52530/#post-528740
To check that, I assume I just pull it out and look for any wear and tear, or is there something specific I'm looking for?

 

[Fire-medic]

This is the order of assembly.

If you don't remove #19, push rod 1 then the ball-bearing part #22 shouldn't be able to fall out.



https://www.ronayers.com/oemparts/a/yam/50045c10f8700209bc7942f8/clutch

 

[Vykk]

Ok, just so I understand what you're saying.

Don't pull out push rod 1 #19. Take the cover off the other side, heard you have to pull the slave cylinder. Then pull-out push rod 2 #21 so the ball-bearing doesn't fall out. Then inspect push rod 2 #21 and probably the slave cylinder since I have it out?

 

[Fire-medic]

Yes, you could do that. If you have the diaphragm spring & pressure plate off, do NOT squeeze the clutch lever.

Use a good-fitting allen socket or wrench (I like a 3/8" drive socket, allen key to remove the screws for the slave cyl.) You don't want to bugger the allen heads on the slave cyl. It's recessed and trying to work on it with a loose/ruined allen head would be a PIA.

If you find brake fluid dripping from the area of under the bike, around the pilot's left footpeg, towards the centerline from front to back of the bike, there's a good chance it's a slave cyl leaking. If you're having a difficult clutch, and it comes back too-far without resistance at the handlebar lever, your clutch O-ring is worn or the slave cyl wall is pitted, or both, in which case you need a complete assembly which is about $129 these days. Part #27 above.

Push Lever Comp

1FK-16381-11-00

Retail Price: $157.99

Your Price: $128.28
https://www.ronayers.com/oemparts/a/yam/50045c10f8700209bc7942f8/clutch
Even if it looks like this you might be able to get a rebuild kit for it, there are aftermarket kits available. Look for All-Balls or K&L. This is OEM:

Push Lever Seal Kit

26H-W0098-00-00

Retail Price: $47.99

Your Price: $36.18



The syringe above is used to perform a reverse-bleed which is a good way to get a bled-clutch or brake lever quickly.

Directions on how to inexpensively assemble your own are included in the thread below. Once you try this, it makes hydraulic bleeding much easier. I only use it on non-ABS brakes.

https://www.vmaxforum.net/threads/clutch-slave-cylinder-replacement.45011/

 

[Vykk]

That's the thing. I feel like the clutch is good to go. When I got the bike, it didn't have much resistance. So, Saturday I got all the old brownish fluid out and reverse bled the clutch and got all the air out of the line, then bled the clutch until clear dot 3 fluid came out of the hose. It feels great now and after I did that and changed the oil i spent most of Sunday cruising around town with no issues. Monday went to work with no issues, then at lunchtime joyride time it started the knocking as I released the clutch.

Do you think maybe after fixing the clutch, something is off, out of line, uncalibrated... after who knows how long since the last time clutch fluid was changed.

With the clutch plates exposed, can the bike be started to see what's happening or to narrow down the clunk noise, of is that not advised?

Sorry, just really stumped on this. Wish I had a dealer or mechanic in town that works on a 20+ year old Vmax.

 

[MaxMidnight]

Do you think maybe after fixing the clutch, something is off, out of line, uncalibrated... after who knows how long since the last time clutch fluid was changed.

If bleeding is all that you did, no.

With the clutch plates exposed, can the bike be started to see what's happening or to narrow down the clunk noise, of is that not advised?

Not advised unless you like paddling in oil.

From what you have written, does the noise only occur when the engine is running and the clutch is pulled in?

The point Mr Medic is making about part #19 is that there is a ball bearing at the clutch end of the push rod (#22) which has been known to pop out and not put back in. So long as you are aware of this then you shouldn't fall into that trap if you dismantle the clutch. It would be prudent to check that a PO hasn't already gone down that hole?

 

[Vykk]

From what you have written, does the noise only occur when the engine is running and the clutch is pulled in?

So, the clunk seems to happen while running, in 1st gear from a stop take off. As I release the clutch and it starts to grab, I hear the clunk. I should be getting my replacement gasket, and I found my old GoPro. Maybe I'll mount it pointing at my left hand to see if I can capture exactly what's going on this weekend.

 

[MaxMidnight]

If the half plate has been replaced with a full plate then you are likely to get a clunk as you engage gear but not the symptoms you describe.

As this happens as you taking up drive another place to check may be the final drive. There have been instances where the middle gear output shaft shears at the nut that retains the UJ. Not sure what symptoms you get...anyone? Relatively easy to check by pulling the rubber boot back.

I think we are all struggling on this one so it's a case of checking what you can so at least you will know what it isn't.

 

[Vykk]

Slapped everything back together, and did some more investigating. Put it up on the center stand. Pulled the boot back a bit and it looks like the middle drive bolt is on there solid. I changed out the final drive gear oil which was pretty black. Started it up and put it in 1st and let the tire roll. Then to 2nd and 3rd. It seems that there is unpleasant noises and vibrations coming from the shaft and hub of the final drive…. So that will probably be the next thing i disassemble.



Maybe it’s simply the UJ connection, but I read somewhere else on here that could be rare. Maybe I need to replace the final drive on a 23 yo vmax with 12k miles

Btw, Previous owner is not responding. I just asked him when the oil was changed last and what type of oil he used, just to start a conversation. Oh well I guess.

 

[MaxMidnight]

I'm not convinced that is an issue and that what you are hearing is the backlash in the system. I suspect that it is hunting as the rear wheel goes from being driven by the final drive (well done for using the correct description! ) to overrun.
If you could put some load onto the tyre I suspect the noise would disappear.

Final drive issues are extremely rare same for UJ's.

I must admit I'm running out of ideas and am somewhat reticent to make more suggestions. My gut feel is that it is something in the middle gear. driveshaft or final drive. The 'clunk' suggests that there is excessive slack somewhere that is being taken up as you feed the clutch in. What bothers me is that gut feel isn't a good basis for a diagnosis.
The other elephant in the room is why did it only manifest after you bled the clutch?

You could check for excessive backlash by putting the bike on the centre stand and in gear (not running) and try rocking the rear wheel back and forth.
If you measure how far the wheel moves which could be compared to a known OK bike?

 

[schudaddie]

Slapped everything back together, and did some more investigating. Put it up on the center stand. Pulled the boot back a bit and it looks like the middle drive bolt is on there solid. I changed out the final drive gear oil which was pretty black. Started it up and put it in 1st and let the tire roll. Then to 2nd and 3rd. It seems that there is unpleasant noises and vibrations coming from the shaft and hub of the final drive…. So that will probably be the next thing i disassemble.



Maybe it’s simply the UJ connection, but I read somewhere else on here that could be rare. Maybe I need to replace the final drive on a 23 yo vmax with 12k miles

Btw, Previous owner is not responding. I just asked him when the oil was changed last and what type of oil he used, just to start a conversation. Oh well I guess.

When tracking down weird noises I use harbor freight’s stethoscope. It’s cheap but works surprisingly well.
https://www.harborfreight.com/search?q=stethoscopeyou will hear things more precisely.
good luck, bill

 

[Vykk]