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Discussion Starter · #61 ·
So, I wasnt able to get the cover off. The bolts are locked on pretty good. I’m guessing there is loctite on them. Do I heat these up with a torch to get them off? I have no clue what color the spring is because it’s so rusted. Should probably just change it and start from the beginning.

Rollers are smooth. Arms look good. There is a little bit of side to side play. Really dirty, will clean them up. But noticed they are an a1-485. Seems this is a 48.5g weight. Should be 44.5. Therefore my clutch engaging at higher rpms, I think should go back down to 44.5. Agree?
 

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You should have the 44.5 for a 340. A 440 single carb takes 48.5.
I've never had a problem with cover bolts, you could try heat.
 

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44.5 gram weights will engage at higher RPM than 48.5. The unknown spring is, well, the unkown factor. You need a known baseline, which the stock set up is. The stock setup may not be perfect for what you are using the machine for, but at least you have knowns that you can adjust from.

Be careful on the engagement RPM with the low speeds you are traveling at. The rpm at your traveling speed must be significantly higher than your engage rpm or you will glaze/burn the belt. However if your engagement is too low the motor will bog and not be able to pull itself. The stock setup should keep you clear of the bog problem and gives you a known baseline if you still need adjustments. Welcome to clutch tuning; there are no magic formulas for what you are doing other than maybe considering Bearcat clutching as a guildeline/reference as well.
 

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In my experience, the weight of the arm doesn't affect engagement rpm very much at all. In simple theory, the heavier arm will engage lower, but you have to consider the location of the weight on the arm, arm profile, and the position of the arm itself at initial shift. The mass doesn't come into play as much until it starts shifting out more and the arm becomes 'untucked'. I have 4 different fan cooled engines with 4 different setups all with different arms, 44.5 48.5 50.5 and 53. They all have right about the same engagement rpm, the weight change comes more into play as the shift develops. This is not a general rule for all arms though, the arm profile is the biggest factor and also why spider shimming can have huge impacts at low speeds, you're using more of the weight. I remember on my 09 sled and my buddies 10, the shimming was off (for those arm profiles), those sleds would burn belts just moving around the garage and loading on trailers, no matter what you did with weights and springs, because the starting off position of the arm is in such a bad leverage position at engagement and low speed. No matter your calibration you were always at that bad leverage disadvantage position, until speed picks up and the clutches open up some. But spider shimming was a huge difference and then you see it drops engagement rpm alot which you have to adjust for. But you really then feel how much more control and response the clutches have near engagement. Instead of flaring rpm with no belt grab or connection, the belt bites and you can easily modulate the torque because you are grabbing the belt with authority.
 

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Discussion Starter · #65 ·
Hey, So all the bolts had loctite on them. Heated them up and they all finally gave. I have a silver spring on it, which is pretty light 72/188.

I like what Gunit said, keeping a constant and then tuning from there. So, I think I will keep the setup as it is for now. Seeing as the weights are slightly heavier than stock, and spring lighter than stock, the engagement should be pretty low. I had no bogging issues last year. So, now that the secondary has a stronger spring we'll see how the hauling goes. Also, the weights are pretty dirty and giving them a good cleaning might make a slight difference too.

I did check the weights bushings as well, there's a slight bit of play (~1/16") which doesn't concern me. Overall everything else looks pretty good.
 

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I do not loctite those bolts or nuts.
You don't have incorrect weights, you have a 440cc single carb and 48.5 is what that engine got, straight from cat.
 

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Discussion Starter · #69 · (Edited)
Ok. Primary all back together. Replaced the bushing in one cam arm, and the pin was worn too so got a new replacement pin. It differs very slightly from the original and I weighed them and it is 1gram heavier. But it seems to be the right part # for my clutch…here’s the pics. I think it will be fine, but do you guys think there will be any balance issues with clutch? @GUnit111 @MNkittykat @660catman

You can see the difference right before the threads. Original is flat, new one is tapered. But the part number (0646-141) definately matches with my clutch and supposed to be for AC 9 tower clutch. Can't wait to get on the snow and try her out!
 

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I will give my best non-answer!

That one gram is not very much but I do try to weight match everything on a clutch. The old pin is wore and has pitting so are you sure the new pin is 1 gram heavier than the old one when it was new?

If you want to take the time to correct the 1 gram, I would group the weights, pins, shims and nuts into three sets and weight match the sets by inter-changing the pieces. ie: heaviest weight in a set with the lightest pin, etc.

BTW, that taper bugs me to no end.... charge us an extra $2 and machine that shoulder square!
 

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Discussion Starter · #71 ·
I know, that stupid taper is a pita! I was thinking of using my Dremel to take it off. Probably would shed the 1g I need. All the other pins were 16g and the new one is 17g. Great point though, I should weigh the cam arms/pins as a whole and compare. I’ll do that and see what I come up with. Maybe mixing and matching will do the trick. Thanks for the idea.
 

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Discussion Starter · #73 ·
Ya, if Gunit’s idea doesn’t work I’ll do that. I Just hate the stupid taper…I prefer the old ones!
 

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Personally, I would have changed all of them.
 
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