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Post by 80sting440 on May 13, 2017 22:03:22 GMT -5
On my '80 Sting the Power Thrust II primary clutch has worn out bushings. It's a good clutch and I like how it works with my engine/drivetrain. If I can find and or make bushings, I may go this route. If not, I'm willing to buy a new Comet 102c.
I've read a previous post by obj1 that he uses the silver spring with 49 gram weights. I assume that's what works for drag racing. I'm looking for a 4500 rpm engagement with full throttle shifting at 7100 rpm. I don't drag race but I do enjoy spirited acceleration.
Any advice on n.o.s. parts for the PT II would be appreciated.
Any advice on the best setup for ditch riding with the Comet...also welcomed.
Thanks guys, Rene
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Post by scorp11 on May 14, 2017 14:36:52 GMT -5
What bushings do you need ? Send me a pm with what you need. I have springs and horseshoe shaped bushings, but not arm pivot bushings or the sheave center bushing.
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Post by 75whip on May 14, 2017 14:39:46 GMT -5
Rene, try hinckley motor sports, or chip for the pt II parts. As for the comet 102c i have seen recomendations online on what spring and weights to use on scorpions, try googleing comet 102c aplacation charts and see what you can find, make sure they are shimed right for the scorpion belt width also
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Post by 80sting440 on May 14, 2017 18:02:51 GMT -5
Thanks guys. I'll be taking it apart tomorrow. I already know that I'll need the sheave centre and the three glides.
I have one of those Comet charts...last time I checked it out, my head hurt for days!
There's more to the weights than considering grams needed. I don't know what profile to get. The charts are full of numbers which mean absolutely nothing to me yet. I guess that I'm just not as smart as I look!
If I ask the online store, I'm afraid that they'll just give me anything to make a sale. I don't mind spending the money on the right stuff...but it's got to be right the first time. That's why I'm asking for help here.
As far as shimmed properly, my store recommends the 1 1/4 width when scorp belts are 1 3/16! Can they be shimmed down (they say it can be shimmed up to 1 5/16)
Thanks Rene
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Post by scorp11 on May 14, 2017 23:35:07 GMT -5
I think the offset is a little different for comets too. Someone who runs them should know that . . . I have a comet somewhere that was run on a Scorp trail sled, but not sure I can give any info without taking it apart. And I don't have the grunt tools so that ain't happening
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Post by 80sting440 on May 15, 2017 5:59:00 GMT -5
I think the offset is a little different for comets too. Someone who runs them should know that . . . I have a comet somewhere that was run on a Scorp trail sled, but not sure I can give any info without taking it apart. And I don't have the grunt tools so that ain't happening Thanks scorp11...no offset specs required.
What I'd like are cam profile specs, i.e. cam arm A2 48 grams, etc.
So far I think that the silver spring is the way to go.
Rene
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tkjoe
L3 The Proven Snowmobile that never lets you down
Posts: 117
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Post by tkjoe on May 15, 2017 17:21:17 GMT -5
Rene,I found an old comet spec sheet years ago and here are the specs it says for the 1980 sting 440.
K-2 Arm p/n #213337A1 SILVER SPRING P/N #204818A
but it shows all of 79 and older scorpion 440's use a B-1 arm # 207801A1 /silver spring. I don't know what the letter/numbers(B-1) mean in regards to weight? hope this helps
Joe
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Post by 80sting440 on May 15, 2017 20:46:25 GMT -5
Thanks Joe...I'll check it out.
That's also the spring that obj1 and other sources indicate...so silver it is.
Rene
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tkjoe
L3 The Proven Snowmobile that never lets you down
Posts: 117
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Post by tkjoe on May 15, 2017 21:40:24 GMT -5
Ok, found a cam arm chart, K-2 arm is 54g and the B-1 is 46g
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Post by 80sting440 on May 15, 2017 22:32:10 GMT -5
Thanks...I too have found that chart.
Rene
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Post by 80sting440 on May 15, 2017 22:36:09 GMT -5
The letters seem to be for the cam profile.
The numbers seem to be for the weight within that certain cam profile.
Rene
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Post by 80sting440 on May 16, 2017 15:48:19 GMT -5
I ended up ordering a new 102c along with a silver spring and A1 48.5 gram cam arms.
The reason I went this route verses trying to find/make new parts for my old clutch is because:
1) I'm getting lazy in my old age
2) I really like riding this sled and plan on putting a lot of hard miles on it along with keeping it running for many years. Parts should be readily available for some time yet.
3) I know that these are good clutches as I have had them along with 108s in the past on my Cats. I just never had to look at them as they never had issues! (if it ain't broke...)
I've noticed that you drag racers haven't chimed in ...keeping your cards close to your chests .
I'll let all of you NON racers know how things turn out come winter...
Rene
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Post by weverat on May 17, 2017 7:42:01 GMT -5
For drag racing I use 108, 102,and Polaris. I have tried several weight and springs. Now days we just throw something in there as a starting point, and then adjust.
The weights will act different when installed in another clutch. The shimming effects engagement too.
Adjustable weights are often used as a short cut.
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Post by stinger440 on May 17, 2017 7:54:43 GMT -5
My $.02 I think you are going to want a little higher engagement then the silver spring will provide. In my experience with these, the cuyuna with scorpion secondary like a heavy tip weight Like the K weight. I have tried using modern Polaris 10 series weights, they take off great but seem flat on the top end. The base combo you ordered might be fine for what you want.
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Post by 80sting440 on May 17, 2017 8:00:39 GMT -5
Thanks for the tips weve.
I've read that each shim increases engagement rpm by 100 rpm and can use up to 3 of them.
I'll have to see who sells adjustable weights.
I suppose one has to figure out which cam profile works best first...my head is starting to itch!
Now I'll have to make/buy comet specific tools
Rene
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Post by 80sting440 on May 17, 2017 8:13:36 GMT -5
Thanks stinger. I could see how the K weights would work differently with their heavy ends. I found some K1 for sale but not K2. Do you know how many grams difference between them?
Rene
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Post by 80sting440 on May 17, 2017 8:41:58 GMT -5
Thanks stinger. I could see how the K weights would work differently with their heavy ends. I found some K1 for sale but not K2. Do you know how many grams difference between them?
Rene I found the difference
K1 59.7 gr
K2 54 gr
Rene
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Post by stinger440 on May 17, 2017 8:48:16 GMT -5
The 54gr weights will probably keep you around the 7100 rpm mark and should pull hard. Little tip, if you can find one cheap, try an 1106 Yamaha belt. You have to adjust c-c a tad. And I like my engagement to be 4000-4500 rpm.
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Post by 80sting440 on May 17, 2017 9:27:15 GMT -5
Stinger, once again, thanks for the tips.
Which spring do run with the k2 to get that engagement?
Rene
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Post by 80sting440 on May 17, 2017 9:54:11 GMT -5
Stinger...I just did the math on the 1106 belt. It's a better compromise than what I was going to try. I was going to use a 1 1/4" wide belt. The 1106 is 1/64" slimmer. or 15 thou. Excellent! It is also a tad longer so I'll increase the c to c which will help me with the removal of my secondary. It will give me more room as the intake manifold is currently in the way. Win win !
Thanks Rene
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