I am considering running ATF in the primary of my '74. Another thread mentioned something about disconnecting or plugging off the hose that feeds into the bottom of the primary case below the clutch pack before switching over. Not sure whatthis hose does? Oil supply? Vacuum? Will I be doing any harm by plugging off this hose? thanks

 

heres the deal..... the primary runs from a feed line from the oil pump. the feed enters the rear of the inner pri right above the chain adj. the breather isvented to atmosphereand the return goes back to the tank.

the problem when you block off theprimary feed is you have to fill it with oil to lube the chain. with the stock clutches and 3 finger hub this will not work out. you will need to put more oil in than the clutches want and thebike will slip at high revs and heavy loads. - also you would need to put abreather filteron the vent line. (and you need to inspect the fluid constantly)

the shovels always had the primary oil back into the engine debate.IMHO if you want to seal off the primary you should run a primo/rivera clutch hub up-grade. this will give you a diaphram clutch and take a3/4 of a quart or more pri. fluid and not miss a beat.

not to push aproduct....but.....this is available with a keyway hub for early or splined hub for late. i did this to my 1974 fxe and never looked back.

what issues are youi having that you want to do this?

 

beeoh,
I am running ATF (Type F) in my primary. I have a Barnett clutch (fibers only, otherwise, stock stuff) that requires it. The ATF seems to be lubing everything just fine but I would have used plain old Harley primary lube or even just engine oil (30W or even 20-50W) had the clutch been able to handle it.

shrktooth,
Sounds like you had no trouble with the Primo/Rivera clutch. If it is the set up I'm thinking of, it was kinda expensive. You think it was worth the bucks?

 

yeah it is pricy.. cost me around 500 bucks. but......worth the money. between that and a 5 speed in a 4 speed box has been very good to me.

i spent years dealing with noisy primary and stock clutches...then came belt drive and it was the hot set-up. except seemed i would break at least one belt a season.....so back to reliable chain.

with a 5 finger hub, big fix, plastic drive fiber, tamer, new shell, barnett soaked in ATF, barnett steels with NO ball 's w/ spring, barnett springs, aluminum pressure plate etc. etc. (not to mention the push rod and throwout bearing..nice heavy duty cable...i had been trying to keep the dam clutches from slippin at high speeds and heavy loads.... seems there was always something i had to sacrifice to get what i wanted. never quite the complete power driveline i would look for.

so you can see that spending 500 buck was about the same amount of money i spent on the driveline upgrade anyway!!!

solution..... dropped in the rivera unit... sealed the primary GOOD. and filled with MOCO primary fluid.. 1 quart. what a difference.(and i didn't need to keep checking my chain fluid level.

you know what i mean?

 

shrktooth,
Yeah. I have had my fill of primary belt drives.
Well, ya got me thinkin' about doing something like that whole new clutch set up.
I'll look into it.
Thanks.

 

shrktooth,
Do have any experience with the Barnett Scorpion clutches for shovels?
They appear similar to the Primo/Rivera Pro except Barnett uses coil springs as opposed to the diaphram that Primo/Rivera uses.
I gotta do something, out on the freeway today I confirmed my clutch has started slipping again. I'm WAY tired of this garbage.

 

no matter what i tried with the sealed primary i could never get that "just right" combo of fluid and adjustments to be satisfied with my clutches at high speeds or ....

havent heard anything bad about them. personally i haven't installed one.

i got mine when they first came out.... i had an issue with the unit ( can't remember exactly what ) but they upgraded the unit and i sent the one i had back to them and got an updated one n/c.

i really liked the idea of the newer style basket with the diaphram. - you do need a special tool to take the clutches out.

the whole issue with the shovel clutches IMHO is the 3 finger stock hub has the 3 nuts and there are 2 studs between 2 of them and 3 between the other 2. (know what i mean?) nut....2 studs....nut.....2 studs......nut.....3 studs. so when the oem clutch drive plate (pressure plate)is engaging it is on an angle NOT FLAT. this was done because of the thump.da-thump characteristic of the shovel engine and front compensator. IMHO by just going to the 5 finger hub you are not curing the " clutches that can't keep up with the engine mods" so after trying about every brand of fibers and steels made ( with many different results ) the only way i was going to keep up with my engine was to improve and get a little into the times...

so i spent the $$$$ and have no regrets.

 

This may help.

Only one picture would copy. I will try to email the other direct.

[IMG]local://upfiles/36456/C916890C59B34A93B6545E450E1340F6.gif[/IMG]

 

great clear photo.

whenrunning an enclosed chain with oiler shut off

i run a breather on the crank vent. also mount it higher than oil pump. no need for oil to drip on my chain.

i put a cap on the rear chain oiler. again no need for it

vent the inner primary and engine together with a T

plug the feed and return in inner primary.(there are different ideas on this but the best way is to remove the inner and do it right.) IMHO.

 

Just out of curiosity did the belt drive you used to run have a tensioner pushing the belt upward at the bottom ( a round metal piece running with a bearing?)