On the way home this evening, at about 70 mph the speedo and tach swept across their respective gauges. I gave a little more throttle, with same result. I safely moved to the right shoulder and shut down the bike. I then started the bike. Before fully releasing the clutch lever, I heard this grinding noise and the bike would not creep forward (I was in first gear). I thought maybe the transmission was overheated, so waited for about 20 minutes before trying again. Now grinding started while the clutch lever was still pulled in. I then called HD Road Assistance and had my bike towed 15 miles home. I have the shop manual and will start diagnosis this week. Any suggestions as to what to look for from those with experience/knowledge?

Background:

I was travelling northbound on I-95 from exit 130 (Rte 3, Fredericksburg, VA) around 9:20pm. It was stop and go traffic because of construction 18 miles ahead. It took about 1 hour to travel the 18 miles. I was slipping the clutch almost the entire distance. The speed picked back up around exit 150 and I was going around 70 mph. I entered the express lanes and about 6 miles later my speedo and tach swept across the gauges.

Thanks all!!

 

I just went and looked the bike over in the light.

The drive belt is there, but there is a pool of transmission fluid on the ground. The tranny fuild level is also not registering anything on the dipstick.

I had been experiencing a trickle of tranny lube on the ground (but no pools), and was going to replace the seals at my next maintenance interval (about now).

I guess I will pull the primary, inspect the clutch pack and replace the tranny seals.

 

I forgot to mention that there is no noise in neutral.

 

There was no noticeable metal in either the drained transmission lube or primary lube. I did not notice any metal shavings until I pulled the inner primary. This is what I found:





I did not notice any damage to the mainshaft up until this point. Tomorrow I will get into the tranny.

 

Very common problem. The splines have stripped out of the pulley. The question you need to answer is if the splines on the main drive gear are still usable. Clean the splines well and look for a ridge where the pulley splines ended. If there is a visible ridge worn
onto the splines, then you'll need to pull the transmission guts out and change the main drive gear and bearing.
The reason this happens, is because even when all the parts are new, this pulley just slides onto the spline by hand.. it's not a press fit or even a push fit.. it's a sloppy fit.
Every time you chop the throttle to decelerate, it tries to shift the pulley even a minute amount on the gear, then when you roll back on the throttle, it shifts it the other direction. This tiniest amount of movement combined with the clamp load the assembly is under, will start to wear down the surface of the pulley spacer and pulley.. as this surface wears down, the clamp load releases, then it starts knocking back and forth and just pounds away at the splines until it rips clean out. Solution? when you put this unit back together, follow the torquing directions carefully, expect to have the proper deep well socket, and a four foot breaker bar to reach the final torque. (I blew a tendon in my hand trying to reach full torque with a 3 foot bar) Better yet, use a T handle drive and two pipes, and two people on it so it doesn't try to bend the mainshaft.
The proper assy procedure puts a tremendous amount of torque on that nut. It should
hold up for a long time. If you want a shade of added insurance, you can put a thin film of the finest lapping/grinding compound (silicon carbide) at the faces where the pulley meets the spacer and the spacer meets the main drive gear... the carbide bits will cut into the two faces and lock them securely. Green locktite will have a similar effect.

Good Luck with that main drive gear... I give you a 50/50 chance of being ok to reuse.

Hogdoctor

 

Thanks Hogdoctor!!

I take it when you say pully you mean the 32T transmission sprocket, yes?

I have attached 4 pages out of my parts catalog. I take it the pulley is item 17 on pages 48 and 49. Is the maindrive gear the same as the 5th gear mainshaft (item 10 on pages 40 and 41)? Is the bearing item 12 or 5 on pages 40 and 41?

(BTW, I had to use an 8" gear puller to get the clutch pack of the mainshaft. It would not come off by hand this time.)

What is the item number for the spacer (for the green loctite to be used on)?

Thanks!

 

The green loctite is #680. It's used for bearing and bushing retaining.
Ron

 

More pics

These are pics of the pully/transmission sprocket spline (note the ridge where the splines were not chewed up):







These are pictures of the exposed main gear drive:







Note that the mianshaft bearing inner race is a lot more than 0.100 inch from the main drive gear. It is more like 0.25 inch:



The exposed splines of the main drive gear look good, but I really cannot tell without either pulling it or comparing to a new one correct?

I do not remember seeing the spacer. I guess it was chewed up.


Thanks

 

Thanks, I will probably give you a call tomorrow if I still do not get it.

Are the Mainshaft Bearing Inner Race and the Spacer sleeve in Fig 7-32, one in the same?

I understand that the Main Drive Gear can come out through the primary side of the transmission. Will A and B have to come off first. How should I go about getting them off?

Lastly, the Main Drive Gear will come out the area occupied by A, correct?

Thanks

 

The spacer is "B" in your pic, it should slide off the gear fairly easily. I don't think it is shown in your parts book. (WTF?) It is clearly shown in my older books. The main drive gear has to come out the right side of the tranny, after you take out the gearset. The inner bearing race "C" has to come off along with top cover, shift forks, etc. before you can remove the gearset. FWIW, the splines on your drive gear don't look too bad in the pic, but its hard to say for sure from here. Get your new pulley and try it and if it doesn't have a reasonably good fit, you're in for a gear change. As Hogdoctor said, its not all that great to begin with. If it was mine, I would do some machine work to spacer and/or pulley(s) so the tranny pulley engages the splines the full length. JMHO, YMMV, etc.

Bob