HarleyTechTalk

Technical Forums => Twin Cam => Topic started by: Adam76 on June 19, 2024, 05:12:10 AM

Title: Clutch diaphram spring rates?
Post by: Adam76 on June 19, 2024, 05:12:10 AM
Hi, Looking for the different clutch springs for twin cams and what TQ/HP each one is rated for.

I remember someone posting the parts list on the forum at some point.

Thanks
Title: Re: Clutch diaphram spring rates?
Post by: Rusticwater on June 19, 2024, 08:23:21 AM
The clutch spring info up in the "sticky posts" section might be helpful. The spring is just one factor for TQ/HP rating...
Title: Re: Clutch diaphram spring rates?
Post by: jsachs1 on June 19, 2024, 02:25:28 PM
Quote from: Adam76 on June 19, 2024, 05:12:10 AMHi, Looking for the different clutch springs for twin cams and what TQ/HP each one is rated for.

I remember someone posting the parts list on the forum at some point.

Thanks
When I use: Diaphragm Spings. I use SE or Alto. 15% stronger than stock. Easy lever pull. I use these springs with an extra plate clutch kit.
37951-98 SE clutch spring, on most of my builds. 386 lbs.
73529 Mid USA Alto clutch spring. Alto supplies SE clutch springs to Harley Motor Co. :up:
John
Title: Re: Clutch diaphram spring rates?
Post by: Adam76 on June 19, 2024, 07:59:14 PM
Quote from: jsachs1 on June 19, 2024, 02:25:28 PM
Quote from: Adam76 on June 19, 2024, 05:12:10 AMHi, Looking for the different clutch springs for twin cams and what TQ/HP each one is rated for.

I remember someone posting the parts list on the forum at some point.

Thanks
When I use: Diaphragm Spings. I use SE or Alto. 15% stronger than stock. Easy lever pull. I use these springs with an extra plate clutch kit.
37951-98 SE clutch spring, on most of my builds. 386 lbs.
73529 Mid USA Alto clutch spring. Alto supplies SE clutch springs to Harley Motor Co. :up:
John

Thanks.
Title: Re: Clutch diaphram spring rates?
Post by: JSD on June 23, 2024, 12:36:48 AM
Energy one extra plate kit and spring. But eventually the splines on hub let go in my situation. 
Title: Re: Clutch diaphram spring rates?
Post by: Adam76 on July 16, 2024, 05:36:55 AM
Quote from: JSD on June 23, 2024, 12:36:48 AMEnergy one extra plate kit and spring. But eventually the splines on hub let go in my situation.

Hey JSD, I've used energy one and Alto extra plate clutch kits with no problems before. What exactly happened with yours?
Thanks
Title: Re: Clutch diaphram spring rates?
Post by: JSD on July 18, 2024, 08:52:31 PM
The hub splines showed wear and was loose on main shaft. The nut is the only thing holding it to outer end of shaft. 
Title: Re: Clutch diaphram spring rates?
Post by: Adam76 on August 04, 2024, 01:46:23 AM
Quote from: jsachs1 on June 19, 2024, 02:25:28 PM
Quote from: Adam76 on June 19, 2024, 05:12:10 AMHi, Looking for the different clutch springs for twin cams and what TQ/HP each one is rated for.

I remember someone posting the parts list on the forum at some point.

Thanks
When I use: Diaphragm Spings. I use SE or Alto. 15% stronger than stock. Easy lever pull. I use these springs with an extra plate clutch kit.
37951-98 SE clutch spring, on most of my builds. 386 lbs.
73529 Mid USA Alto clutch spring. Alto supplies SE clutch springs to Harley Motor Co. :up:
John

Hey John, IIRC there's a spring that sits between the stock 96" HD spring and the SE spring? I think it was used in the 103" Police bikes... it had a pink mark on it. Do you know about this spring and what lbs it is?
Cheers
Title: Re: Clutch diaphram spring rates?
Post by: jsachs1 on August 04, 2024, 01:46:11 PM
Quote from: Adam76 on August 04, 2024, 01:46:23 AM
Quote from: jsachs1 on June 19, 2024, 02:25:28 PM
Quote from: Adam76 on June 19, 2024, 05:12:10 AMHi, Looking for the different clutch springs for twin cams and what TQ/HP each one is rated for.

I remember someone posting the parts list on the forum at some point.

Thanks
When I use: Diaphragm Spings. I use SE or Alto. 15% stronger than stock. Easy lever pull. I use these springs with an extra plate clutch kit.
37951-98 SE clutch spring, on most of my builds. 386 lbs.
73529 Mid USA Alto clutch spring. Alto supplies SE clutch springs to Harley Motor Co. :up:
John

Hey John, IIRC there's a spring that sits between the stock 96" HD spring and the SE spring? I think it was used in the 103" Police bikes... it had a pink mark on it. Do you know about this spring and what lbs it is?
Cheers
My list of springs, show part # 37807-03 spring as 364 lbs. for 103"  Cop bikes, Trikes, & CVO. Pink mark. I never used one. My go to spring has ALWAYS been H.D. 37951-98, S&S, Alto 386 lbs. Even small, skinny finger females never had a complaint, or problem using them. Higher H.P. bikes, and/or heavy riders I use Barnett SCORPIAN, or BANDIT clutch assy. :wink:
John
Title: Re: Clutch diaphram spring rates?
Post by: jsachs1 on August 05, 2024, 01:49:51 PM
I forgot to mention. When I use a Bandit Clutch Assy., I use a Cometic primary cover gasket that's .094" thick.
Part # EC117188ML.
John
Title: Re: Clutch diaphram spring rates?
Post by: Adam76 on August 06, 2024, 06:30:01 AM
Quote from: jsachs1 on August 04, 2024, 01:46:11 PM
Quote from: Adam76 on August 04, 2024, 01:46:23 AM
Quote from: jsachs1 on June 19, 2024, 02:25:28 PM
Quote from: Adam76 on June 19, 2024, 05:12:10 AMHi, Looking for the different clutch springs for twin cams and what TQ/HP each one is rated for.

I remember someone posting the parts list on the forum at some point.

Thanks
When I use: Diaphragm Spings. I use SE or Alto. 15% stronger than stock. Easy lever pull. I use these springs with an extra plate clutch kit.
37951-98 SE clutch spring, on most of my builds. 386 lbs.
73529 Mid USA Alto clutch spring. Alto supplies SE clutch springs to Harley Motor Co. :up:
John

Hey John, IIRC there's a spring that sits between the stock 96" HD spring and the SE spring? I think it was used in the 103" Police bikes... it had a pink mark on it. Do you know about this spring and what lbs it is?
Cheers
My list of springs, show part # 37807-03 spring as 364 lbs. for 103"  Cop bikes, Trikes, & CVO. Pink mark.
Quote from: jsachs1 on August 05, 2024, 01:49:51 PMI forgot to mention. When I use a Bandit Clutch Assy., I use a Cometic primary cover gasket that's .094" thick.
Part # EC117188ML.
John
[/b] I never used one. My go to spring has ALWAYS been H.D. 37951-98, S&S, Alto 386 lbs. Even small, skinny finger females never had a complaint, or problem using them. Higher H.P. bikes, and/or heavy riders I use Barnett SCORPIAN, or BANDIT clutch assy. :wink:
John


Thanks for the info. 386lbs should be all I need for now. :teeth: