Board index Flathead Power-Technical Questions, Answers, and Suggestions Big Twin Flatties VL 4 spd. Conversion ?'s

VL 4 spd. Conversion ?'s

Post Mon Nov 10, 2008 10:59 am

Posts: 39
Location: Seattle, WA, USA
Hello. Slowly working on my bits and pieces VL and have a couple questions.

1. Has anyone here installed an HD 4 spd. in their VL using the stock motor? If so, can you provide a bit of info. on what you did to reach glory?

It looks as though I'll definitely have to remove the trans. adjuster boss on the 4 spd. The 4spd.'s mounting studs drop right into my VL frame's factory trans. mounting holes, but my clutch basket sprocket is going to be quite a bit off from inline with the motor sprocket. Any creative solutions?

2. Can someone tell me what the proper offset of a VL wheel is? I'll be running a 16 drop center laced to a VL hub w/ VL mechanical brake. I figure that if I lace the wheel to factory offset and have the motor in its stock location, I'll only have one problem to creatively solve - trans. location.

Thanks for any and all help,

Post Sun Nov 16, 2008 8:22 pm

Posts: 14
Location: Daly City CA U.S.A.
Tony, your project has a special place for me I have had this expeiance with a ULH in a VL frame using a 36 and up four speed , 45 tanks for gas and oil and glide front end and 1958 juice rear brake...

First you are on the way with cutting any boses that interfere with mounting the trans directly anf flat to the four slots in the VL frame, with this done. We had to set the engine case in the frame with lower end and a sproket after welding up the existing frame motor mount holes & filling the motor mount tables flat we lined up the engine and clutch sprockets and and marked the motor mount for re-drilling... I heard that you can also move the clutch basket out by running two friction discs on the clutch hub , never tried that one though. Now on the kicker side we made a bracket that went from the top side cover bolts to the frame and bolted a kidney style tool box to the braket and the rear fender..many thought it was a 45...

Now to adjust the primary chain we welded a piece of 3/8" x 1 or 1 1/2 flat stock bent in and L and welded to the bottom of the frame and the L came up on the frame side of the inner primary cover and i drilled holes to hold the nylon rubbing block found on late style enclosed primarys and cut a window in the tin inner primary and bent the eges over so it was't sharp and gave the inner primary some strength and of corse a hole for the floorboard cross bar to go through... after that it was just a mater of spacing on the rear axle...I ran 23 on the engine and 24 on the countershaft with andrews gears in the four speed with a suicide clutch and gate shift on the tank...

When I say we ,I am giving credit to Larry Riley who left us long before PC's were invented and whos motto on his business card was Old or New We Can Do, and without his help this project would have never gotten past an idea.

I have some pics I can pass on, you can ping me at

Tom (08)

Post Thu Nov 20, 2008 12:49 pm

Posts: 39
Location: Seattle, WA, USA
Thanks so much Tom. I'll shoot you an email for those pic.'s now.

Post Fri Dec 05, 2008 1:23 am

Posts: 646
Location: Detroit
You didn't specify what year mainshaft/trans you want to use. I stuffed an EL knuck motor into a VL and had to use a 65 - 69 mainshaft to line it up. I started with a year 1974 trans and changed the mainshaft. I don't know if the VL sprocket shaft sticks out the same dimension as an EL knuck, so my method might be only half of your equation. The idea of two clutch fibers in the hub doesn't sound like a good idea. Hanging the clutch drum that much further out will increase the leverage on the mainshaft at the least and the bearing surfaces vis-a-vis the hub and drum mating one to the other might present another problem.

If I were you I would try this: install the engine with the motor sprocket;
install the trans with the clutch hub, pack, and drum;
take a straight edge and check the alignment on both sprockets.

In my experience, off a little bit hurts nothing. Off a lot, and right this minute I can't remember in which direction, will mean your clutch is always engaged no matter what you do. I started with a 1974 (long) mainshaft and had to go shorter. I did not try a 64 and earlier shaft because the 65 - 69 appeared to line up, which it did, and everything worked fine. You will have to use a 65 and later trans case for the bearing support if you any 65 and later mainshaft. Do not cut the aluminum primary support ears off of the case. Just remove the 4 studs. The 65 and up cases are stronger in the main drive gear area because of those ears and the extra metal.

At one point I even considered moving the engine over but the more I thought about it I realized that was an exceptionally stupid idea. Matching up the mainshaft as I indicated above and using a Superglide clutch arm /eliminator style gave me a flawless clutch.

Good luck.
New Knuckleheads? Thank, you, Jesus!!

Post Wed Dec 31, 2008 12:31 am

Posts: 148
Location: Dorothy, NJ. USA

Honest John here. I have been running a 46 U engine in a 34V frame with a later, 49-58 3sp+R transmission. All I did was cut off the adjuster, rat tailed the left front motor hole and when it came to lineing up the primary chain/motor/clutch, I just planned on putting in an extra fiber disc on the back of the hub NEXT time I had it off. That was in the 70s. I have had no trouble with it since. I have not babied it, in fact the 3 speed causes me to rev it up a bit between gears due to the spread between gears. Even if I was pulling a hack as I was planning I wouldn't use a 3 speed. If I ever wear this one out I'll putin a 4 speed.. Oh, you have to use a 26 tooth sprocket to clear the lower frame leg ANDuse a tank shift trans 'cause the ratchet set up won't clear the middle frame/seat tube.. Yes I love mine. I've got a 32V I'm gonna build up with stroker wheels, 4 1/2 S&S for U"s. Just a few mods, groove for oil and hoop over a couple (5) teeth cam wise. Zoom....
Check the alignment on yours tho, I've heard that it is different on each one tho. I use the old Diamond style chain cover due to the U motor and later style clutch which is much thicker. I have had no problems with my set up in all these years. Most "bikers" don't even know what they're lookin at. Especially when I back out.

Post Wed Dec 31, 2008 12:39 am

Posts: 148
Location: Dorothy, NJ. USA

Forgot to add, I used a 48 to57 mechanical rear brake setup in the V frame, Just had to spread the legs a bit with a jack the first time. No major stretch. It all seemed to line up fine. no wierd wear or tracking . good for over 100 mph! Any ? just E me.

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