Comet 102c Spring/weights

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farleyjd400
Posts: 102
Joined: Sun Dec 11, 2016 4:26 pm
Real Name: Andy
Location: Ham Lake MN

Comet 102c Spring/weights

Post by farleyjd400 »

I know this topic has been brought up over and over because I have been reading all of the old topics on this the last couple of days. What I read over and over again is that John Deere used different color codes for the springs compared to what Comet used. Example: A Deere Blue spring is the same as a Comet white spring. I never did find what crosses over to what. I tore my 102c clutch apart on my Cyclone(this is the newer 102c) because it was not performing well on the low end. I found a black spring and U weights. I had a set of good used F weights and installed them then ordered a new silver spring from New Breed. Put everything back together and WOW what a difference, the Cyclone performs a lot better. So my question is, is the silver spring I used actually a silver spring per JD color or is it something else?

Regarding cam arms (weights), it does not look like you can buy new F cams anymore. So the only option is to find NOS or good used correct?

I have a chance to buy a brand new Comet 102c for a very good price that I would like to use for a Cyclone 440 build, but im not sure what to use for the cams. I would like to stick with the set up I have listed above but there is a lot of new cam choices from Comet. Some of the weights(grams) are close to the F cam but the ramps look a lot different. Could I use factory Deere F weights in the brand new 102c Comet clutch? Or has anybody else used a brand new Comet clutch and set it up for a Cylcone 440?

Thank you
Andy
1976 Cyclone 340
1977 Cyclone 440
1978 Cyclone 440
Ajc
Posts: 16
Joined: Sun Oct 11, 2015 11:40 pm
Real Name: Andrew Clark
Location: Le Sueur MN

Re: Comet 102c Spring/weights

Post by Ajc »

Here is Deere to Comet Cross Reference. When it comes to clutching there is know 1 setup. There are optimal setups but even these very based on what your doing. The stock setup is a good overall base. You can run your F weights in a new clutch.

Now if you have a Cyclone between Serial NO. 55,001-70,000 cluching should be.
340 F weights Silver spring 2 spacers
440 F weights Black spring 2 spacers
Serial NO. 70,001 and up
340 R weights Silver spring 1 spacers
440 R weights Silver spring 2 spacers
*** Clutch settings for Altitude 0 - 2,000 feet ***

Here is a little info if you want to go more in-depth.

Springs ---
Black spring Tension at 1 1/8" - 198 Black spring Tension at 2 3/8 - 50
Silver spring Tension at 1 1/8 - 190 Silver spring Tension at 2 3/8 - 85

The black spring has a lower initial spring tension at 2 3/8" So it will engage sooner.
The silver spring has a lower spring tension at 1 1/8" So it will hit full shift sooner and at a lower rpm.
Capture2.PNG
What the springs are doing is setting the power band. A shim will shift the power band up but the slope will stay the same. (see chart)

Weights
Weights are a bit more complicated. They control the rpm between initial engagement to full shift.
Now a F and an U weight have a very similar profile with U being heavier.The heavier weight will get to full shift sooner. Which will put more load on the engine. Ideally you want to be at full shift by peak horsepower.
There's a lot more to weights if you want to get into it.
Capture1.PNG
F weight
Capture.PNG
Capture.PNG (121.16 KiB) Viewed 7338 times
U weight

AJC
Last edited by Ajc on Wed Feb 28, 2018 8:27 pm, edited 1 time in total.
1973 400
1975 800
1975 800 - (Parts)
1975 JDX8
1983 Sprintfire - (Vintage Challenge Finisher 2022)
harleysportster
Posts: 2965
Joined: Thu Jul 14, 2005 12:00 am
Real Name: Pat Scott
Location: Southeast Pa.

Re: Comet 102c Spring/weights

Post by harleysportster »

Ajc wrote:Here is Deere to Comet Cross Reference. When it comes to clutching there is know 1 setup. There are optimal setups but even these very based on what your doing. The stock setup is a good overall base. You can run your F weights in a new clutch.

Now if you have a Cyclone between Serial NO. 55,001-70,000 cluching should be.
340 F weights Silver spring 2 spacers
440 F weights Black spring 2 spacers
Serial NO. 70,001 and up
340 F weights Silver spring 1 spacers
440 F weights Silver spring 2 spacers

Here is a little info if you want to go more in-depth.

Springs ---
Black spring Tension at 1 1/8" - 198 Black spring Tension at 2 3/8 - 50
Silver spring Tension at 1 1/8 - 190 Silver spring Tension at 2 3/8 - 85

The black spring has a lower initial spring tension at 2 3/8" So it will engage sooner.
The silver spring has a lower spring tension at 1 1/8" So it will hit full shift sooner and at a lower rpm.
Capture2.PNG
What the springs are doing is setting the power band. A shim will shift the power band up but the slope will stay the same. (see chart)

Weights
Weights are a bit more complicated. They control the rpm between initial engagement to full shift.
Now a F and an U weight have a very similar profile with U being heavier.The heavier weight will get to full shift sooner. Which will put more load on the engine. Ideally you want to be at full shift by peak horsepower.
There's a lot more to weights if you want to get into it.
Capture.PNG
F weight
Capture1.PNG
U weight

AJC
I want to point out a correction needed for the previous info.
The correct cam arm for Serial NO. 70,001 and up
Both 340 and 440 Cyclone,AM54279 which is stamped "R"
All the clutching info is for Altitude of Sea Level to 2000 ft.
'76 440 cyclone
'76 440 liquifire
'78 440 Cyclone
'75 JDX8 (sold to a member here)
'78 Liquifire(CrossCountry Clone)
'80 Liquifire(sold)
harleysportster
Posts: 2965
Joined: Thu Jul 14, 2005 12:00 am
Real Name: Pat Scott
Location: Southeast Pa.

Re: Comet 102c Spring/weights

Post by harleysportster »

farleyjd400 wrote:I know this topic has been brought up over and over because I have been reading all of the old topics on this the last couple of days. What I read over and over again is that John Deere used different color codes for the springs compared to what Comet used. Example: A Deere Blue spring is the same as a Comet white spring. I never did find what crosses over to what. I tore my 102c clutch apart on my Cyclone(this is the newer 102c) because it was not performing well on the low end. I found a black spring and U weights. I had a set of good used F weights and installed them then ordered a new silver spring from New Breed. Put everything back together and WOW what a difference, the Cyclone performs a lot better. So my question is, is the silver spring I used actually a silver spring per JD color or is it something else?

Regarding cam arms (weights), it does not look like you can buy new F cams anymore. So the only option is to find NOS or good used correct?

I have a chance to buy a brand new Comet 102c for a very good price that I would like to use for a Cyclone 440 build, but im not sure what to use for the cams. I would like to stick with the set up I have listed above but there is a lot of new cam choices from Comet. Some of the weights(grams) are close to the F cam but the ramps look a lot different. Could I use factory Deere F weights in the brand new 102c Comet clutch? Or has anybody else used a brand new Comet clutch and set it up for a Cylcone 440?

Thank you
Andy
If the part number for the new Comet Clutch is not 212600A, it is not the correct clutch for the Cyclone.
'76 440 cyclone
'76 440 liquifire
'78 440 Cyclone
'75 JDX8 (sold to a member here)
'78 Liquifire(CrossCountry Clone)
'80 Liquifire(sold)
Ajc
Posts: 16
Joined: Sun Oct 11, 2015 11:40 pm
Real Name: Andrew Clark
Location: Le Sueur MN

Re: Comet 102c Spring/weights

Post by Ajc »

harleysportster wrote: I want to point out a correction needed for the previous info.
The correct cam arm for Serial NO. 70,001 and up
Both 340 and 440 Cyclone,AM54279 which is stamped "R"
All the clutching info is for Altitude of Sea Level to 2000 ft.
I fixed the post. Thanks

AJC
1973 400
1975 800
1975 800 - (Parts)
1975 JDX8
1983 Sprintfire - (Vintage Challenge Finisher 2022)
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jep_800
Posts: 445
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Real Name: Jason
Location: Grand Forks, ND

Re: Comet 102c Spring/weights

Post by jep_800 »

Also, new F weights are available, they are just called F-2 now. I think the difference being that they have the bushing (plastic?) inside the weight where the pivot arm slides through. They should be the same weight, but they give you that range of + or - .75gr. I got a set at Pat's Small Engine for $18.00 plus shipping.

Jason
1975 John Deere 800
1975 JDX8 (VC Finisher 2019)
1976 440 Cyclone (VC Finisher 2022)
1974 El Tigre 440 (Sold)
1996 Arcitc Cat 440Z
farleyjd400
Posts: 102
Joined: Sun Dec 11, 2016 4:26 pm
Real Name: Andy
Location: Ham Lake MN

Re: Comet 102c Spring/weights

Post by farleyjd400 »

This is all awesome information and just what I was looking for, Thanks everybody for the great information

It was not until this year that I really started to learn clutching. The more I learn and the more I test different combos the more fun I have. The small change I made on my Cyclone amazed me at how much more performance the sled felt like it had. Made for a totally different, but funner sled
1976 Cyclone 340
1977 Cyclone 440
1978 Cyclone 440
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