Chattering noise at 55 to 65 mph

[True1shot]

Learned something today! I have a Honda VTX 1300 with a Motor Trike conversion. I've had this chattering noise at about 60 mph and finally today I fixed it! The noise was coming from the front u joint and by changing the propshaft position in the u joint spline the noise would get worse or better depending on the rotational position. Took about 5 tries with different prop to u joint positions but I finally got the noise to go away! Don't know if anyone else has heard of this but but boy am I glad that freakin noise is gone!

 

[Gold Rush]

Learned something today! I have a Honda VTX 1300 with a Motor Trike conversion. I've had this chattering noise at about 60 mph and finally today I fixed it! The noise was coming from the front u joint and by changing the propshaft position in the u joint spline the noise would get worse or better depending on the rotational position. Took about 5 tries with different prop to u joint positions but I finally got the noise to go away! Don't know if anyone else has heard of this but but boy am I glad that freakin noise is gone!

Sounds like the driveshaft timing was not set correctly. I'm surprised it didn't shake you off the trike. You might watch that U-Joint real closely for premature ware...

 

[True1shot]

Hey Gold Rush: Is there a scientific way to do this driveshaft timing, or was my trial and error the right way?

 

[bustedwing]

There is a right way to do this. When you slide the two shafts together, look at the position of the u joints on each end. They should line up perfectly. So even if you are off by one tooth it will set up a vibration and will be rough on the life of the u joint.

 

[keepinon]

The MotorTrike Service Manual posted in the stickies, says to off-set the engine u-joint by one tooth ahead of the rear. When I replaced my drive shaft, I still had a vibration at that setting. Ended up going two teeth ahead of the rear, now there's only a very slight vibe at 25 mph, which passes quickly.

But no noise...

 

[Gold Rush]

The MotorTrike Service Manual posted in the stickies, says to off-set the engine u-joint by one tooth ahead of the rear. When I replaced my drive shaft, I still had a vibration at that setting. Ended up going two teeth ahead of the rear, now there's only a very slight vibe at 25 mph, which passes quickly.

But no noise...

I imagine the "Perfect" timing position depends on the shaft being balance perfectly also. Maybe it is something that can be tweaked by moving one or two teeth on the spline. The new MotorTrike driveshaft is keyed so it will only go together one way. Hopefully their balance process puts it right on the mark. Mine is.

 

[True1shot]

Most all the vib is gone now, I'm gonna play with it some more and ill let you know how I come out. Thanks all!

 

[True1shot]

Ok I ended up 1 tooth in front of the rear. Chatter is completely gone at 60. Now there is a slight chatter at 30 to 35, I think it's been doing it for so long the ujoint is worn. I plan on ordering a new one and start the timing process again only this time start 1 tooth ahead.