New vibration

[howardg]

Vibration, about 60 mph plus. New u=joint and yoke put on by a dealer last year. 2003 GW 1800 trike

 

[Haste Maker]

What trike kit do you have?

 

[Ed Hobgood]

Does it feel like tires? Is it in the front or back? so many questions.

 

[howardg]

I have a 2003 Lehman trike, and you can feel it in the handle bars and the foot boards. I recently added dyno beads to rear tires and didn't remove the weights. I thought it was the drive shaft but it is fine.

 

[CrystalPistol]

I posted this a few short years ago on another forum, I have reposted it a few times elsewhere .... but it might help. The events took place maybe 2010 I'm guessing without going to look it up in my book.

Just passing on an experience.

A while back we headed out one day for a group ride and it was one of the few where we got on the interstate and as we had a good ways to go, we kicked it up to 65 - 70. It's not often that I cruise this trike at speeds above 65, I just avoid Interstates.

I noticed a vibration through the pegs that I didn't recall there before, it went away with power or coast, but as I rolled back and forth on the throttle it was worst when there was no load on the joint at all like when the throttle was just enough to match rpm to speed. When I speeded up more, it was noticeably worse ... but not bad, just enough to be noticed. I suspected a Ujoint as they'll do that as power or load tends to center them and they flop when unloaded sometimes thus swinging the driveshaft like a jump rope.

I left the ride and went home at 55 or less on old road, not bad now, and I pulled the shaft at home. Rear car size U-joint was tight, as expected it being bigger and getting regular greasings.

Front Honda U-joint which was original and seemed OK, maybe a little easy to flop around, but no slack in joint. I thought maybe the splines were worn but could see no wear on either motor output shaft splines or drive shaft splines even with magnifying glass.

I ordered a Valk U-joint, it's the one Honda ships for all 1500s now. It came in a few days later and I slipped the shaft back out and put the new front U-joint in with plenty of grease on the splines making sure that the front and rear joints were in proper phaze.

Took it for a ride, it was as bad if not worse! Damn it!

Well, a few nights ago I was going over the trike for a couple rides coming up, I wasn't sleepy, and I had her jacked up putting grease in the rear joint and adjusting the rear drum brakes and I decided to take another look at that Honda Valk U-joint. Well, I pulled the shaft and joint, wiped the joint clean of excess grease, and checked the fit on the splines, no appreciable slack.

Then as I rotated the joint looking and wondering why the hell I have this persistant vibration, I noticed something. It looked like the joint cross wasn't centered just right in the front yoke, the rear yoke looked like it was a hair out to one side. The surfaces of the yokes at widest point is machined, so I got the idea to measure the depth at each of the 4 bearinmg cups from this surface. The cups in the rear half of the joint were very nearly the same, maybe a hair difference, but certainly within a few thousadths of being the same.

The cups in the front yoke, the yoke half that slips up on the motor output shaft, ...
... weren't close. 65 thousandths difference between the two. The cross was not centered in the yoke!

Manufacturer's defect. These cups are pressed in and staked. The staking points on the side where the bearing cup was pressed deepest didn't go all the way to the cup, so I figuured I didn't need to cut them out ... there was room to move it.

Well, I looked through sockets and found one that fit inside the yoke and was against the stake points withouit being on top[ of them, this socket was a 12mm HD for use with air wreches I think. Inserted in behind the bearing cup, it would contact the cup at the outer edge without flatening the center hump flattening it, and it would go inside the stake point circle. Using this socket and a hammer and measuring after every whack, I finally drove that cross back to center point between the yokes, I even centered up the two cups on the rear half of the yoke as they were a few thou out. When done, the cross was centered as near perfectl;y between the yokes as was possible to measure with my tools. I had moved the joint 30+ thousandths in the one yoke back to center.

These cups are tight in the bores, the stake points were just for safe measure.

Anyway, put it back together with more good grease in the splines and in phaze and we took her for a ride. Took it out for ice cream and hit a section if interstate between two exits out west where there's no traffic and run it up faster than I will say .... and the vibration is gone! Finally!

Now I'm going to dig out the original joint and check it too

I did check the original joint, as far as I know it was the OEM from 1997. It was centered, the joint was just a little loose so it's like a third spare. I have another couple of tight good spares ..... and if I recall correctly, one of them needed some tweaking to center the cross in the yokes.

 

[Lee H. Mann]

I have a 2003 Lehman trike, and you can feel it in the handle bars and the foot boards. I recently added dyno beads to rear tires and didn't remove the weights. I thought it was the drive shaft but it is fine.

Howard,
What did you change that could have caused the vibration ? Or was the vibration always present ? My experience has been a vibration that arrives at 60MPH and gets worse as speed increases is usually wheel and tire balance related.

 

[howardg]

I recently put Dyno beads in the rear tires and didn't take the weights off.

 

[Haste Maker]

If there is some tire lube inside the tire from mounting the tire the beads will stick to the lube & throw the tire out of balance...I always use the Centramatic balancers

 

[howardg]

I give up, I'm taking to the shop next week

 

[hog driver]

Vibration, about 60 mph plus. New u=joint and yoke put on by a dealer last year. 2003 GW 1800 trike

may be the wheel weights

 

[howardg]

No the vibration stops when you pull in the clutch.

 

[Haste Maker]

Ok you have problems in the drive line or the rear end

 

[CrystalPistol]

No the vibration stops when you pull in the clutch.

When you pull the clutch in, the U-joint is still lightly loaded in a coast mode as it transmits power from rear end to transmission and still turns those gears in that oil bath.

Only time that U-joint is totally unloaded while turning is that sweet spot when you have throttle adjusted so that there is no power applied to accelerate or hold speed .... and yet enough throttle to not slow the bike ..... that's when that U-joint is totally unloaded and when it will ... if worn cross trunions or bearings or if loose on splines, etc, ... vibrate most noticeably. If you gently rotate the throttle back and forth at 60 mph and feel that vibration in the pegs, etc as you roll it between coast and accelerate, that's likely the reason.

Loading often .... not always .... but very often .... tends to center a worn U-joint.

Just my experience FWIW.

 

[extreme10]

Centromatics work really well.

 

[howardg]

Lee, I sent you a PM

 

[howardg]

Found that the drive shaft was bent (don't know how) and I ordered a new one from Lee H.Mann, thanks Lee for being on this site it is great and all the members.

 

[CrystalPistol]

Found that the drive shaft was bent (don't know how) and I ordered a new one from Lee H.Mann, thanks Lee for being on this site it is great and all the members.

Ummmmhummmmm ........... ain't run over no alligators lately have you?

Still .....

No the vibration stops when you pull in the clutch.

..... would seem to me that a bent shaft caused vibration would still be there then.

Oh well, no mind .... glad you got it in hand ........

 

[howardg]

I have a new drive shaft on the way and will post on after I install it, thanks everyone

 

[howardg]

I got the new drive shaft installed today and it is better, but I'm still happy with it and don't know what else to do.

 

[Haste Maker]

Your wheels both front & rear maybe out of balance...I would try some centramatic balancers both front & rear...I have seen the time when I would have bet the farm that my front tire was the problem..only to learn it was the rear tire...now this was on a 2 wheeler.