REV WONT REV

[halffast800]

I just got back from my first ride in the Bighorns. Snow was good but the sled wasnt. I had problems with rpm. I only made 7200 max, and some times it would bog out and die. After this happened it would only run 4000 max. I changed the plugs and it ran like a champ but only 7200. Plugs looked awesome but wet. Jets are 470. Could it be the clutch sticking and not letting it backshift? 07 800r Summit X 144

 

[sledsrock]

IMO check in the following order:

1. Raves
2. DPM
3. Clutches

 

[xj1978]

How many miles? Rebuilt?

 

[halffast800]

Yes, rebuilt last year, has about 600 miles on new skidoo motor. I took apart the primary clutch and one set of buttons are wore down more than the other two, and the spring has wear marks on one side of it. Any help would be great. Thanks for the tip, I will try to check it out some more tomorrow.

 

[halffast800]

Also, the left carb has an open nipple on the electronic module thats bolted to it. Any ideas? Im pretty mechanical, but some of this new stuff sucks snoflap.

 

[Dynamo^Joe]

IMO check in the following order:

1. Raves
2. DPM
3. Clutches

4)install stock muffler back on to test

 

[halffast800]

Any idea why the spring would rub on one side? I will try the stock muffler. How do you check a DPM?

 

[snowyo]

replace inner bushing and spring cap and primary spring in primary.And the nipple your talking about not having a hose on it is normal.

 

[xj1978]

replace inner bushing and spring cap and primary spring in primary.And the nipple your talking about not having a hose on it is normal.

x2! Spring cups are a high wear item on this model year.

 

[winter brew]

Make sure the white plastic sleeve around the spring has not been removed.
By chance do your lights not work?? Bad relay will act as you describe but the headlight won't work either.
If that's not the case, check the basics....exhaust valve function (pull the black plastic cover and start the sled...they should both suck in),
compression and crank runout (PTO stub).
I am betting on exhaust valve stuck/broken or torn bellows if your only seeing 7200.
If it was clutching it would be something VERY obvious.

 

[halffast800]

I just checked compression,seemed low at 110 psi. on both cylinders. Could stuck exhaust valves do this or am i thinking backwards. Im a total newbie to all of this. Also, shouldnt there be springs under the exhaust valve covers? And with 600 miles on a skidoo motor, what kind of help should i expect from the dealer who put it in? Thanks for all your help, maybe someday i can return the favor.

 

[winter brew]

No springs under the covers.
110 at what altitude? Should be 135-145 at sea level but gauges vary.

 

[sledsrock]

I just checked compression,seemed low at 110 psi. on both cylinders. Could stuck exhaust valves do this or am i thinking backwards. Im a total newbie to all of this. Also, shouldnt there be springs under the exhaust valve covers? And with 600 miles on a skidoo motor, what kind of help should i expect from the dealer who put it in? Thanks for all your help, maybe someday i can return the favor.

Valve position wont really effect compression readings and the rave springs are inside the bellows on the 3D raves (800R motors). What elevation are you at??

 

[t30mg]

His home elevation is 1750'.

Does seem to vibrate bad?

I read on doo talk that the 07's had a prob with crank phase if the pins are not welded.

Anyone here experience that?

 

[halffast800]

Crank run out checked good. Bellows are good. I talked to the guy I bought it from and he said it has solid pins in the clutch, and ran it on 3 while riding the trail in MN. When he went to the hill he put in hollow pins. Who makes the best clutch kit for ditches and mountains with out changing pin weight? I want it to really yank my arms off, so maybe changing clutching everytime would be the answer. Opinions welcome.

 

[Dynamo^Joe]

halffast800)he said it has solid pins in the clutch
and ran it on 3 while riding the trail in MN
---18,8 gram pins

When he went to the hill he put in hollow pins.
---empty hollow thread-able pins 1-3/8 @ 12.1g (plus whatever setscrew)

Who makes the best clutch kit for ditches and mountains with out changing pin weight?
---wish you the best on finding that. Im not saying you wont find that, just saying wish you the best on that (for maximum performance w/o changing pinweight)

I want it to really yank my arms off,
---then you'd have to calibrate per elevation range.
Remember about every 1000 feet direct elevation increase you lose about 5hp-ish.
100% @ 0000' elevation [151hp]
89% @ 3280' elevation [135hp]
78% @ 6560' elevation [118hp]
60% @ 9850' elevation [90hp]
...if you were to be on clicker 2 in minnesota at 1100 feet and go to 9000 feet, you would have 8000 feet elevation increase and lose about 40+hp then according to clicker numbers you would have to clicker up to 8...oh wait, you only have up to 6, so now whatcha gonna do when you observe 7700 rpms and have no more clickers left to play with?

so maybe changing clutching every time would be the answer.
---if you "want it to really yank my arms off" then yes, I would say the slight effort one needs to put into changing the calibration for elevation increase/power reduction, then that would be the best option.

Opinions welcome.
---that's my opinion, don't take my word for it, be diligent and research this out.

 

[xj1978]

Crank run out checked good. Bellows are good. I talked to the guy I bought it from and he said it has solid pins in the clutch, and ran it on 3 while riding the trail in MN. When he went to the hill he put in hollow pins. Who makes the best clutch kit for ditches and mountains with out changing pin weight? I want it to really yank my arms off, so maybe changing clutching everytime would be the answer. Opinions welcome.

Your gonna have to tune your clutches for elavation! There is no way around that. If you want it to yank your arms off then you need to talk to Big John about an 860SHR upgrade.

 

[halffast800]

Thanks. I'm learning faster on here than I could have hoped. Any help is great, so talking it out here is good for me. I don't even mind criticism. Just makes a smarter tuner out of a rookie like myself.