open primaries, trans plates and all that jive...

[71butcher]

so im wanting to hook my 82 80" shovel from my fxr to 4 speed ratchet top trans. in a rigid harmon frame
i want an open 2" w/kick only. will electronic ignition on the shovel be a problem?

ive heard things about an offset for a cast primary as opposed to tin.
its got a tapered shaft on the trans, what does that mean i have to order for a clutch basket?
as far as a trans plate. ive seen an $80 piece from seven sins that has dual adjuster screws or can i just buy an old sheet metal one and weld some nuts on it.
what the fuck do i have to order? who has my all my 7/16 wrenchs and who is drinking all my damn beer?

seriously i have little to no idea what im doing. help me out guys.

[Dragstews]

Let's talk about your trans for a moment....

What you have now is the 4-speed that used the inner primary as a support of the trans case...
Meaning there are no track lugs casted into the bottom of your case... Only the case studs will be carrying the loads once the primary is done away with..


64 and back trannys had a trans plate with slots cut in them for track lugs to engage.... This design carries the loads...

After/market does make late tranny cases with the track lugs for running open belt/chain drive....
May save you from seeing a busted case in the future....

[BnC]

^ Thats fair but you see a lot of later harleys running open belt... youd think 5 case studs could handle some abuse.

[Dragstews]

Youd think 5 case studs could handle some abuse.

Most likely would until Jack Daniels is along for the ride....

(He's known to Kick Ass)

http://youtu.be/rq4DV7BID5U

[71butcher]

the trans I bought has just the studs on the bottom. no lugs. has a few numbers cast into it to.
one on the bottom next to the studs is 34703-77
and x8716 on the side

[71butcher]

its just going to have to be alright i guess. i dont have another trans. so about the clutch and primary.

[Blackbetty]

Drag, are you saying only 64 and back transmissions are suitable for open primaries?

[71butcher]

Drag, are you saying only 64 and back transmissions are suitable for open primaries?

Boy, thats what it sounded like. ive seen them all over the place for that to be the case.
i mean this isnt a dragbike or hotrod. im hoping itll just be ok.

[boomboomthump]

I don't proclaim to be an expert and Dragstews is certainly a knowledgable member here but I don't believe that is exactly accurate.

Aren't the lugs on the older trans cases and the recess in the plate simply for alignment? I don't believe they bottom out in the recess of the plate. If they did, it would be critical for them to all be flat and on the same plane.


I don't doubt folks have cracked a trans case but I would believe it is more in relation to lack of shimming (regardless of trans lugs or not).

[71butcher]

see, i didnt know about shims either. i have a bare frame, a bare trans and an engine still in my fxr. i have no idea what i need. help me out.

[Blackbetty]

You should get a manual, but occasionally you need to shim the engine and or trans to sit squarely on the mounts

[Dragstews]

Drag, are you saying only 64 and back transmissions are suitable for open primaries?

No..... Not at all....

What I am saying is the 64 and back trans used track lugs to control the twist.... They lock the case in those tracks...

When the Ele. Starts came out in 65 with the Alum. primary s those lugs went bye-bye....
Now your taking that design back to an era that it wasn't meant for by deleting the primary and running open drive...

After/market seen this as a weak area and added those lugs on their cases for this reason of open drive...
Let's say you have a good built big inch Shovel.... 93", 96" or 98" inches of screaming Herd of pony's and you throw on a 180 tire for a bit of grip.... No motor plate tieing the trans to the motor... No lugs... A few drinks under your belt and a little show-boating leaving the bar..... That trans is going to be doing some work... It will most likely be breaking out the case at where the studs are at....Two of them are in corners on the chain side, they will go first then the domino effect follows shorty after.... That's all that is working is the studs...

Sure, there are the ones that get by with the stock set-up... Stock motors keeps from tearing up stuff... Also riding like the Devil, himself, is after your ass would not be wise to do...

Just saying....
If your going open drive, best to do a little overkill in the tranny mounts riding hard....... Or ride styling and profiling and stay out of the throttle....

[71butcher]

well im hoping with a mostly stock shovel ill be ok.
and i have a sportster for a whipping boy lol.

[71butcher]

http://www.ebay.com/itm/BDL-8MM-2-OPEN-BELT-DRIVE-PRIMARY-1955-E1984-HARLEY-PANHEAD-KICK-START-BOBBER-/141485800406?pt=Motorcycles_Parts_Accessories&hash=item20f135fbd6&vxp=mtr

will this work?

[47str8leg]

Yeah.it will be fine I've had one on my pan/shovel since 2003 w/no problems. Then again ,I've gotten over show-boating w/ my GTO'S years ago so ,while I cruise between 70-80 mph and occasionally roll on the throttle above that, I don't launch like I'm drag racing or need to smoke the tires. It's .50 w/some headwork and a mild Andrews j cam.