7900 RPM's

[Phonix]

I bought a 09 Assault this year with a 155 dragon skid with the Polaris 5.1 track.

I noticed yesterday I was peaking out at 7900 RPM on some long pulls.

Don't know very much about clutches yet on snowmobiles. Whats the next step for me? I hear they should pull about 8200-8300 range.

I was riding at 5,000 ft if that matters. Sled runs good in the mean time.

 

[miller tools]

What weights are in it

 

[Phonix]

I am at work. Is there a way I can see what weights are in it without removing the primary?

Also I would assume they are stock.

Thanks for the info.

 

[KrazyKen]

If it's stock in the primary then I beleive they came with 10-62's and a 140/330 spring.
First off, how many miles on the spring? If it's the original spring I would say it's getting weak. If you replace it I would suggest the SLP blue/pink (140/340).
Does it ever spike above 8100 rpm then drop down to 7900<? SLP makes a spacer that goes under the helix in your secondary clutch that helps hold RPM (backshift). It makes a slight change in helix angle.
And yes you can read the numbers on your weights by shining a small light down next to it without removing your clutch or anything.

 

[Phonix]

I bought the sled used, don't know if the spring has been replaced. The sled has 1200 miles. He gave me recipes of a rebuild on a 2010 motor 300 miles ago. Hard to tell if he did any clutch maintenance done. On the max rpm setting after a ride it shows 8100-8300. But when I watched it on trail pulls and fresh powder pulls it would not climb above 7900. I wish this sled had a analog tach.

Thanks a lot for your input. I will check the weights when I get off work..

 

[KrazyKen]

ya the max RPM deal is not a good representation of what is really happening. Watching the tach on a steady pull is a better read of how your sled is performing.
For $25 I would eliminate the primary spring question and throw one in it. I instal a new one every year. Actually I'm waiting for my second to arrive today since I broke one last weekend.

 

[Phonix]

Sorry If I come off as a retard. Would I have to change weights when I changed the primary spring?

 

[KrazyKen]

No. To change the spring all you have to do is remove the six bolts on the primary cover. It's tight next to the belly pan but you can pull out against the plastic and get in out. just be careful not to damage the bushing in the cover that rides on the clutch center shaft. The spring comes right off.
when you install the cover just use a criss-cross torque pattern and slowly work it in so you don't bind the cover. DON'T over tighten those bolts, not sure off hand but they are like only 15 ft pds or something. Pretty much wrist tight with a 3/8's ratchet. Call your dealer for torque specs, I have them at home but not with me now. Re-torque after a short ride to be safe.
If you have the 62's i wouldn't change them, as a matter of fact a lot of guys run 64's (like me). More weight will result in less peak rpm so at this point I would leave them. If you have 64's try the spring first and if you're still not even close on rpm maybe try 62's.
good luck!

 

[Phonix]

Ordered the spring. Thanks again! I will post the results.

 

[Ski-Dont89]

cover bolt torque is 100 in. lbs FWIW.

 

[volcano buster]

Verdict?

 

[MORSNO]

The OP was a one and done guy, he hasn't been on here in over two years (1-22-2013).

 

[volcano buster]

The OP was a one and done guy, he hasn't been on here in over two years (1-22-2013).

And that is supposed to get him out of following up with the verdict to answer my curiosity? Sheesh, what is this forum coming to?

This forum has changed a bunch in the last several years though...

 

[diamonddave]

And that is supposed to get him out of following up with the verdict to answer my curiosity? Sheesh, what is this forum coming to?

This forum has changed a bunch in the last several years though...

If he was running the correct weights for corresponding altitude, then he most likely had worn-out pistons. Very common for the 800 CFI-4.

 

[MORSNO]

And that is supposed to get him out of following up with the verdict to answer my curiosity? Sheesh, what is this forum coming to?

This forum has changed a bunch in the last several years though...

No, it doesn't get him out of it, I also hate it when guys ask a question, get help, and then never report back. But obviously he left years ago and hasn't been back.

 

[volcano buster]

If he was running the correct weights for corresponding altitude, then he most likely had worn-out pistons. Very common for the 800 CFI-4.

How do you get the pistons in the clutch?