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Old 12-12-2012, 12:59 AM   #1 (permalink)
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Help with jetting!

Hey guys, I'm having a little problems with my gas mileage. I own a 1999 rmk 700 and it gets horrible gas mileage in low elevation. But if I go up in elevation, (not very much) it gets great mileage. I'm not sure whether to change the jets down one or not. I dont want it to run too lean. Any ideas?

Thanks!!
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Old 12-12-2012, 10:21 AM   #2 (permalink)
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If the sled is jetted properly for high elevation, it will be running lean at low elevation. Does the sled have the altitude compensating stuff on the carbs? It could be that the ACCS is not working properly.

You are right to be concerned. I bought a 97 RMK 700 that was jetted on the edge for high elevation and burned a hole in the piston on the first day riding by running it hard at lower elevations. Not fun. Ran GREAT right up to the point of failure, though
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Old 12-12-2012, 11:17 AM   #3 (permalink)
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Originally Posted by BC_Dan View Post
If the sled is jetted properly for high elevation, it will be running lean at low elevation. Does the sled have the altitude compensating stuff on the carbs? It could be that the ACCS is not working properly.

You are right to be concerned. I bought a 97 RMK 700 that was jetted on the edge for high elevation and burned a hole in the piston on the first day riding by running it hard at lower elevations. Not fun. Ran GREAT right up to the point of failure, though
I have NOT purchased an altitute compensator. I plan on getting one now im starting to realize they really make a difference!
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Old 12-12-2012, 12:52 PM   #4 (permalink)
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Cool

Quote:
Originally Posted by BC_Dan View Post
If the sled is jetted properly for high elevation, it will be running lean at low elevation. Does the sled have the altitude compensating stuff on the carbs? It could be that the ACCS is not working properly.

You are right to be concerned. I bought a 97 RMK 700 that was jetted on the edge for high elevation and burned a hole in the piston on the first day riding by running it hard at lower elevations. Not fun. Ran GREAT right up to the point of failure, though
Dan my sled has the ACCS unit attached to the air box, it seems very rich at or near sea level, when i rode for the first time i pulled all 3 plugs to see how things looked and it seemed to me they should have been darker, i was riding at or near the 4,000-4,600 level. Is there any way a guy can test that or check anything out that you know of?
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Old 12-12-2012, 02:09 PM   #5 (permalink)
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ACCS should handle the altitude changes pretty well. Some people opt for yanking it off and doing their own jetting, but that assumes a fairly constant level of elevation. I ride anywhere from 4,600-11,000 feet in a day. I'm not going to stop every few thousand feet to fiddle with jetting, so I let my ACCS do its thing. Do I notice differences in performance at different elevations? ...sure, I do... but as long as it runs decent overall, I don't worry about it.
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Old 12-12-2012, 05:11 PM   #6 (permalink)
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The plugs should be cardboard brown at pretty much any elevation with the ACCS. If it's working. A lot of people had issues getting it to work and removed it.

Jetting without a compensator is a compromise; do you jet for high elevations so you have power, but chance a burndown at lower elevations, or do you jet for low elevations and run pig rich at high elevations? Or do you stop and change jets? I ride from 5 to 8k and jet for about 6 on the sleds with carbs.

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