Loud Clank on Acceleration and Deceleration (not good)

[pancho]

    "Will probably end up taking the entire final drive apart and redo with (some?) new parts. "


There is no reason to get into that kyllini, if the backlash is appropriate and it operates smoothly, there is nothing in there to "clunk",,, thoroughly check the likely suspects first,,  dampers and ujoint.

[kyllini]

That's definitely the plan Pancho.
While I have this thing apart, should I also change the wheel bearings?
I hear they should be changed out (especially the left?).
Hate to have to take this thing apart again, it's becoming a PITA.
Bike's beautiful and low mileage (approx. 7500 mile), but has been a real project to date.
I was hoping to get some riding in the season before my next project (bought the Aux. Fuel tank) and was to install this winter.

[pancho]

Hey kyllini, the bike might be a project right now, but when you have it together and running right you have a winner that will take you anywhere you want to go.

I would just inspect the bearings, if they are smooth and rotate nicely with your finger with a bit of drag and no catching or noise, I would leave them and stay after that clunk.      Really like to ride it and hear what you are hearing.

[The emperor has no clothes]

Hey kyllini, the bike might be a project right now, but when you have it together and running right you have a winner that will take you anywhere you want to go.

I would just inspect the bearings, if they are smooth and rotate nicely with your finger with a bit of drag and no catching or noise, I would leave them and stay after that clunk.      Really like to ride it and hear what you are hearing.

Maybe he could post a call for someone in the area to take a look and listen

[Ricky-D]

I agree with you.

5 degree play at the output shaft is excessive.

It also depends upon which gear you are in.

Different gears have different power transmission paths.

I suggest to get a pointer and measure the play in the

output shaft more accurately.

***

[kyllini]

Still stumped!

So I'm posting pictures of what I see so far.

I haven't seen anything obviously wrong, actually all looks good.

I tried to twist the U-joint (until my wrist hurt) and didn't detect much, (if any) play.

The only thing I can say may be an issue is a slight play in the wheel dampers (2-3 of them were somewhat loose - but not really deteriorated).

See what I've posted and let me know what I'm missing.

Thanks to all in advance (I'm super frustrated!).

[Skinhead]

Your splines, pinion cup, and U joint look good, but it looks like you can use some dampers.  I'd clean everything up and replace those.  Put one end of your u joint in a vise and use a a pair of vise grips or channel locks on the other  end and see if you feel any play in it.  I doubt you will find any, but better to be sure before you button it up.  All the black rubber dust on the wheel hub indicates worn out dampers.

[kyllini]

Sounds reasonable, and the one other thing I noticed is slight oil or grease or.....something on the rear wheel rim on one side.
Not sure if you can tell on the picture but take a look.


Maybe if the dampers weren't real tight that maybe some of the lubrication within the wheel area is being expelled?
Can the dampers themselves be causing such a noticeable clunk?
Sure hope so.

[Bone]

Changed the dampers in mine 2 weeks ago. Couple of the holes looked a little out of round. Wow is what the new ones feel like and a slight clunk I gave the gearbox credit for is gone.
Hang the old ones on a wire later if you get 1 or 2 looking bad use your back-ups instead of buying a complete set.

[The emperor has no clothes]

Still stumped!

So I'm posting pictures of what I see so far.

I haven't seen anything obviously wrong, actually all looks good.

I tried to twist the U-joint (until my wrist hurt) and didn't detect much, (if any) play.

The only thing I can say may be an issue is a slight play in the wheel dampers (2-3 of them were somewhat loose - but not really deteriorated).

See what I've posted and let me know what I'm missing.

Thanks to all in advance (I'm super frustrated!).

I think the grease on the wheel is excess getting by the o-rings, no biggie just clean everything up put in new o-rings& grease. I think your dampers are toast. I didn't think they would be the cause of the loud clanking you were talking about but maybe they are. Did you remove the ring off the driveshaft on the pinion cup end ? If it was me I would clean everything, new o-rings ,grease,dampeners. And see if it stops the clank. Good luck

[kyllini]

I recorded myself twisting the output shaft back and forth while in first gear.

Put the video on youtube - listen and let me know if this sounds normal.

Again remember that it's about a 5 degree twist.

https://www.youtube.com/watch?v=jDYsTkxY2Sc

[Bone]

That isn't normal.

[kyllini]

Yeah, that's what I was afraid of.

I heard that there was a certain amount of normal play but how much is normal?

Anyone else out there have a similar issue or am I'm the only one with a possible problem in the tranny?

[R J]

I recorded myself twisting the output shaft back and forth while in first gear.

Put the video on youtube - listen and let me know if this sounds normal.

Again remember that it's about a 5 degree twist.

https://www.youtube.com/watch?v=jDYsTkxY2Sc

In that video, almost straight in, it looks like the driveshaft turning.

What is it hitting?

Can't tell what it is hitting but it is something that is not normal.

I'd investigate that further for your problem.

[kyllini]

I'm turning the output shaft and it's engaging in first gear (hitting the tooth on the gear).
The problem is when I twist in the opposite way, it seems to take too long before engaging in the previous tooth.
In other words, it seems like there's a bit too much slack, but then again I didn't design this so I'm not sure what's normal.
Has anyone else measured the slack in the output shaft in gear?
Some slack would be normal, but how much?

[The emperor has no clothes]

Yeah that's not right. I couldn't get any play in mine when I replaced the ujoint. I'm not sure where to go from here but you are probably going to have to remove the engine.

[pancho]

Your splines, pinion cup, and U joint look good, but it looks like you can use some dampers.  I'd clean everything up and replace those.  Put one end of your u joint in a vise and use a a pair of vise grips or channel locks on the other  end and see if you feel any play in it.  I doubt you will find any, but better to be sure before you button it up.  All the black rubber dust on the wheel hub indicates worn out dampers.

I'd do what Skinhead says with the ujoint before proceeding, just to rule some stuff out.

[Skinhead]

Your splines, pinion cup, and U joint look good, but it looks like you can use some dampers.  I'd clean everything up and replace those.  Put one end of your u joint in a vise and use a a pair of vise grips or channel locks on the other  end and see if you feel any play in it.  I doubt you will find any, but better to be sure before you button it up.  All the black rubber dust on the wheel hub indicates worn out dampers.

I'd do what Skinhead says with the ujoint before proceeding, just to rule some stuff out.

+1

[kyllini]

Ok - going to doublecheck the U-joint and then take it from there.
Probably going replace the wheel dampers anyway.
Any good old posts on how to drop the motor / gearcase? - (just in case)

[R J]

I wouldn't worry about dropping the motor just yet.

Let's don't get the cart ahead of the mule.

Inspect the u-joint and replace the dampers.

Then we move from there if it is still there.

Thank you Brother.

Peace, RJ.

[kyllini]

That's the plan RJ 

I'm definitely not in a hurry to start taking the motor apart.

So still hoping that it's still dampers, U-Joint, anything but "that".

John

[kwboxer]

My bike (59,000) started to do the same thing today. When I decelerate the noise is deafening. Any word on what your problem was? Any help would be appreciated.

[Ricky-D]

Reviving this old thread may not be the best course of action,

especially since the noise is "deafening" It may well could be

the universal joint.

And a note to the OP. That clank caused from your action

is perfectly normal. There is engineered clearance between the

dogs and the slots within the transmission, which is what you

are hearing. Not gear teeth, as you surmise.

***

[Rio Wil]

I recorded myself twisting the output shaft back and forth while in first gear.

Put the video on youtube - listen and let me know if this sounds normal.

Again remember that it's about a 5 degree twist.

https://www.youtube.com/watch?v=jDYsTkxY2Sc

Try twisting the output shaft while in 2-3-4-5 gears to see if it is the same noise and amount of twist.  On my bike, the rear wheel will rotate about 1 1/2 inches while in first gear and about .5 inches in 5th gear. Obviously your bike is apart, but might be informative for when put back together

[westnek]

Thank ya kind sir.   

I hope ya lose also, but if ya do, take the bet $$$ and put it towards the parts needed.

In the future, keep those 2 little holes clear when reinstalling these parts.

Later, I got to go mow grass.   Riding mower w/power steering.   LOL......

   
 I havnt got that far  my ? is  ''where are the two little holes ''if I have to go down that  road

thanks     westnek   ride safe

[kyllini]

Sorry for the delayed update but was out of commission for over a month (accident at work) and just got back on my feet.
Changed the rubber wheel dampers, U joint and did maintenance on the rear end pumpkin, engine oil, etc...got the it back together and it feels much better.
Any clunky-ness left is probably normal for these bikes (even for one with 7300 miles).
It does run real strong & feels rock solid, unfortunately all this may have for nothing because with an injured right ankle and wrist, I may not be able to continue riding the bike (it's too big / heavy).
It was definitely a real bear trying to maneuver at slow speeds.
Hate to say it, but after all that, I may end up putting it up for sale (maybe a trike is in my future).

[Tailgate Tommy]

Sorry to heard about your injuries kyllini! Hope you mend fast and can keep your Valk.
Tom (tkylli)