Clutch slips bad at 70 MPH/

[partshunt]

I have a clutch problem that mistifies me. The clutch adjustment is correct, I have proper cable and release rod clearance. Clutch works great in normal running. Does not drag, gears engage nice, no clunk. However, if I run her at 70 MPH its fine but when I torque it up to pass a car or just accelerate, the clutch starts slipping and the engine RPM climb like crazy. I even added a turn more on the good clutch springs with no help. Could my clutch release rod be "walking in" at hi speed? Has anyone had the same kinda problem? Its only a stock FL, notheing exotic in the engine.Fuel is 89 Octane, no nitro, ha ha......Joe

[Cotten]

Joe!

Can we assume this is an OEM clutch?

The one time it occurred for me was with my 86" '65, pulling a hack;
The steel plates had heat-warped to produce five blued areas like petals of a wild rose.

....Cotten

[mbskeam]

more info needed....
beltdrive?
clutch plates (brand)
springs too light?

[Bosheff]

Does it ever slip when tryin to start it. Does the clutch totally disengage with the lever pulled in when kicking it through in nuetral....bosheff

[partshunt]

Thank you for your respnses guys, here are more details:-
-New clutch plates, dont know brand but the material is reddish in color.
-OEM Steel plate, five pin upgraded
-Clutch engages smooth when first or second is engaged from nuetral, hot or cold, very nice. Dont suspect warped plates.
-No slippage when kicking it over.
-clutch grabs good when starting out and generally running fine at any speed around town.
-Stock restoration enclosed chain drive.
-useing EP 90 oil in gearbox. Installed clutch tamer 3 years ago.
-spring tension set at 15/16ths originally, I added half a turn, no improvement.
This thing had a tendancy to slip over 70 MPH right from day one but its more obviose now or worsening. Like I mentioned, its a stock FL set up, nothing exotic. I dont suspect worped or oiled plates at this time, clutch clears very nice and its smooth and slick going into gear. no draging, no clashing, nicer than my 07 Classic in that regard... thnks,,.joe






;-

[Sir_Rat]

Partshunt.....You can play around with your springs n steels n frictions and 3 vs 5 finger hub all you want and at best come up with a combination that works. Or, if you don't mind sacrificing originality and you want to end your clutch problems once and for all go get the Barnett Scorpion or the BDL ???Competitor I think is the name and end up with an upgrade that makes you grin from ear to ear. It will feel like a different bike...more like a lighter jap bike with butter smooth shifting, no creeping and you can sit at the stoplight and shift through the whole range of gears. Your bike will even feel fatser too. The Barnett is more expensive and a little trickier to install. Expect to pay about $500 - $600 for the Barnett and about $300 - $400 for the BDL. Warning...once you do this you will never ever again be satisfied with the factory setup. This is of course my opinion only. Good luck to you

Aloha....Mike

[hogboy52]

High gear is exactly the time when a clutch will begin to slip. It's certainly true on a car and is nothing unusual. Tightening the springs 1/2 turn is hardly significant. Tighten them till it quits slipping or get stiffer springs. The five disk setup makes for a stronger clutch with less spring pressure.

[Cotten]

Folks,

You may all quote me on this:
Five adjustor stud clutch hubs are stoopid:
Ever try to level a table with five legs?

Furthermore,
I will take the crustiest of OEM friction discs (prepped of course) over ANY modern aftermarket imitation.

Asbestos rules!

...Cotten

[steve_wood]

Partshunt:

+1 to Sir Rat (sorry Tom). I put on a Barnett Scorpion and it solved my problem. I still have the stock clutch. Maybe if they ever invent meds for instant brilliance I can figure out what's wrong with the stock one.

[partshunt]

[quote="hogboy52"]High gear is exactly the time when a clutch will begin to slip. It's certainly true on a car and is nothing unusual. Tightening the springs 1/2 turn is hardly significant. Tighten them till it quits slipping or get stiffer springs. The five disk setup makes for a stronger clutch with less spring pressure.[/quote]

I agree with you, in hi there is no more reduction she is one to one and the engine seems to just start torkin at 70 and like you say, it seems the clutch is just not holding when the engine starts produceing. It feel like the engine is aproaching its power band and needs stronger holding pressure. Maybe springs from later 80 inch shovel is in order here. The stock clutch has a good history with thousands and thousands of em running around over the years, street dragin, police abuse, drills teams rideing hell out of them. they are a good clutch when correctly built. no point in re inventing the wheel here. this bike is not on Nitro so I dont think I need a modern Hi Tech clutch at this point. Its just a run around town stock FL restoration, hell, its not even running an FLH cam. I sure do apreciate all and everyones input with very good points made. I must thank everyone for thier well put response....Joe

[mbskeam]

if you have Alto (red) plates, I had those in my bike for less than a week, these slipped real bad.
I have the green type sold by VT(police special), these have given me the best results.

[partshunt]

mbskeam:- I think like you say, dump those red whatever they are clutch plates along with springs. An asbestos clutch and stronger springs will probably fix it. I will post my results here, thanks to all...Joe

[Bosheff]

Have encountered many sets of the "Green" VT plates over the years. In every instance where they had been run for any length of time at all, they seemed to corrode the steels. I really don't have any use for the stock H-D fiber plates, but the green ones are total junk in my opinion. By the way, where does a person get their hands on real asbestos plates these days? I am under the impression they were outlawed years ago....bosheff

[PanPal]

I bought my green clutch plates 6 years ago. They have been working well for me.

[partshunt]

Thank you, sounds like I should "go green", haha. Possibly, these are like what I might be needin, who are these plates made by?...thanks..Joe