Trans shift arm wobble prob : V-Twin Forum: Harley Davidson Forums

Locodave · 08-24-2009, 02:43 AM

Hi, 1999 Fat Boy. 5 speed. 8,600 miles on it. I can grab the arm at the trans that connects to the rod that connects to the shifters toe end & sloppy at the arm. Shifts ok up & down. About 1/2 inch forward & back play to the foot toe shifter. That dosen't worry me as much as when I push the arm in & pull it back. ( Towards the trans & pull outward. ) I have about 1/2 inch of play. I tryed to tighten the allen bolt & it's tight. Neighbor that owns a Harley told me the allen's threads were worn & why the wobble. Sometime this week I'll take the allen out to look at the threads. Ever hear of this? Common? Dave

LoCo1969 · 08-24-2009, 09:19 AM

If the bolt is tight, it's not the threads. It's the splines in the shaft of the arm. The inner primary needs to be removed to change that. Before we assume that though, really tighten that bolt up. You can crank on them pretty good and it'll crush the arm onto the shaft. I imagine you'll strip the hex of the bolt before the threads and if it isn't tight by then, the primary is coming off anyway.

boston rg · 08-24-2009, 11:21 AM

I must have tightned mine about 3 or 4 times last year- seemed to always come loose- I read in here to change out the screw, something about the threads getting stretched out from overtightning it. It has been fine ever since...

Locodave · 08-25-2009, 02:22 AM

Hi, From what I've read. The original part is aluminum. The shaft is steel. After market is chromed steel. I'll try to see how the gap looks on whats on there. Aluminum teeth would go out 1st before the steel teeth on the shaft? You have to take the inner primary off to swap to a steel one? Thinking if the teeth are worn out on the arm. Might work on taking out the bolt & get a new one, using a washer if none is there. I want to ride it & if I snap the bolt. It gets ugly. Dave

tebglide · 08-25-2009, 08:22 AM

Locodave - I've had the same problem on a 99 RK and an 03 RG. I got the same story about stretching bolts from a mechanic at the local dealer. So everytime it would get loose I'd install a new bolt. This worked for a year or so. It finally got to the point that even with a new bolt it would not get tight. I installed a SE 6-speed in the RG about a month and a half ago. You are right about the materials. The shaft is steel and the shift arm is aluminum. The splines in the shift arm were pretty boogered up. I put a 3/32" steel roll pin through the shift arm and shaft. I don't know if this is going to be a permanent fix yet or not as I only have about 4500 miles on it. So far all the shift linkage is still good and tight.

wood02 · 08-25-2009, 09:37 AM

2003 FLSTCI 66,000 miles...lose shifter shaft lever...original bolt is #856A (allen head)...I used #3970B (acorn head)...the owner of local HD shop Bud said that this #3970B is a sportster bolt. He has been using it for years to fix the loose shifter problem. He said to loctite with blue and lube under the head of the bolt and really crank down on it. You can get a socket and ratchet on this instead of trying to tighten with an allen wrench. It has "fixed" my problem...so far. The mechanic's call this a "Bud bolt" in honor of Bud...he has since passed away. Bud was problem solver and usually the fixes were permanent. The bolt sells for about $10.00 from this dealer.

Ed Y · 08-25-2009, 09:52 AM

For years, I've always taken the bolt out on new bikes, put never-seize on it and tightened according to torque spec's. Never had a problem with one yet.
If you don't do when new, then the fixes above are necessary. I do like the idea of the different bolt head instead of an allen.

Locodave · 08-25-2009, 11:57 AM

Hi, Thanks for all the info. I'm thinking of hardware store. Match up the old with a grade 8 allen. I have the allen head sockets to put a extention & tork wrench on it. I have the manual so I can look up the tork specks. Using a acorn head, you would have to use a 6 point socket as I've had the 12 points strip a nut before. Never-sieze instead of lock-tite as if it gets loose again. I want to be able to do it. Too bad I have to take off the inner primary to swap out the arm. I'd just get a metal chrome one & be done with it. I won't be able to work on it till Sat. My only day off. I'll get back on what I found. Dave

Locodave · 08-30-2009, 12:05 AM

Hi, Got it done today. Took the allen bolt out & looked at the threads. Good, cept for the well hole where the allen goes in to tighten up the bolt. Crudded up. Cleaned the hole out. I'm thinking anyone that had tryed to use a long L allen to tighten it as I did at 1st. Because of the crud. The allen didn't go in more than 1/4 to 3/8 inch & slipped on them. I used a lock washer. Socket with the allen tip worked well with an extention. It had a grade 8 bolt in there already so I used it again. Used my wratchet to get it tight as I could & brought out the breaker bar. Slowly tryed to tighten it more as I can feel the tension better. 1/4 turn more & it's like new again on the play. Hopefully the lock washer took the place of any lock-tite. Dave