Stowed last spring with non-ethanol and a heavy 10oz. dose of ATF run throughout the fuel system incl. direct into cylinders after shutdown, normal Marine Stabil on a minimal amout of fuel (whatever the syphon missed)..thanks to the rec's I got here.
This season added 3gal. of fresh fuel and fired it up..still heavy smoke but running good took out and ran a couple miles easy then back to camp to top off the fuel..back out on the lake with a full tank and all good, later a 115 mi. trail run. so made it through the 9 month storage..motor running strong, as intended.
Couple observations I'd like opinon on please:
Lake runs were on 6" of fluffy ontop a great base of 3" frozen stiff wet snow.
RPM: just a hair under 9k
MPH: 80
BACKFIRE: on my trail run, at the second stop 80mi. into the day the unit gave me a faint backfire on restart.
MPG: @83 mi. (trail, avg. 30 mph) filled 8.9 gallons so about 9 MPG
This season added 3gal. of fresh fuel and fired it up..still heavy smoke but running good took out and ran a couple miles easy then back to camp to top off the fuel..back out on the lake with a full tank and all good, later a 115 mi. trail run. so made it through the 9 month storage..motor running strong, as intended.
Couple observations I'd like opinon on please:
Lake runs were on 6" of fluffy ontop a great base of 3" frozen stiff wet snow.
RPM: just a hair under 9k
MPH: 80
BACKFIRE: on my trail run, at the second stop 80mi. into the day the unit gave me a faint backfire on restart.
MPG: @83 mi. (trail, avg. 30 mph) filled 8.9 gallons so about 9 MPG
mile9c1
New member
What'd you average last year? Last year on 01 vmax 600 deluxe I was averaging 11mpg on trails. This year, same sled with a 1.25" track and tuner skis I'm seeing 9.5mpg and same 85mph top speed. I have stock jetting but I think I'll recheck my needle positions.
mile9c1
New member
P.S. mine liked to backfire last year when the carbs were dirty.
I had the faint backfire on hot start last year too..maybe a little worse..the engine is sure running smooth & powerful can't imagine any carb issues based on the way it sounds or runs... the low MPG is a concern though but your 600 is simular? I also have a 700SX thats faster getting 12+? is this common MPG for 600's?
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mile9c1
New member
I always figured 11mpg was common for a stock 600 on hardpack. The 700's have different gears so they theoretically should turn lower RPM's at the same speed (thus saving fuel). FWIW, my Viper so far is also averaging 9.5mpg with the same 1.25" track.
I noticed the belt is in great shape but slightly low on the secondary (ribs just high, belt just low) I consulted the manual and I have NO bolts on the secondary to adjust?..The belt adjustment might explain the MPG & MPH..I hoping any way.
mrviper700
VIP Lifetime Member
I noticed the belt is in great shape but slightly low on the secondary (ribs just high, belt just low) I consulted the manual and I have NO bolts on the secondary to adjust?..The belt adjustment might explain the MPG & MPH..I hoping any way.
the bolts to adjust it are on the backside of the sec clutch, you have to remove the clutch to get to them.
also, I noted you said you were almost 9000rpm, you need to adjust the front clutch weights to bring the rpm down to 8500rpm, the higher it revs the worse the mileage will be all over the power range, because your running at a higher rpm all over slipping the belt likely and the clutching and gas mpg go hand in hand. Likely will need to replace the tip rivet in the clutch weights with a heavier one.
mrviper700
VIP Lifetime Member
cant adjust @ 2700 mi.?
sorry, but i cant comprehend the meaning of that statement, youll need to explain better.
sorry mrviper that doesn't make sense.. WTH..must have been caught up in the Packer win.. anyway the clutch removal weights and rivets probably more than I want to tackle myself..was hoping for a easy tweak to move the MPG up..at least I know what to mention if I decide to take it into the shop..at $4.00 per gal a 33% improvement almost pays itself.
is 12+ MPG realistic for this (all stock) machine?
is 12+ MPG realistic for this (all stock) machine?
the bolts to adjust it are on the backside of the sec clutch, you have to remove the clutch to get to them.
also, I noted you said you were almost 9000rpm, you need to adjust the front clutch weights to bring the rpm down to 8500rpm, the higher it revs the worse the mileage will be all over the power range, because your running at a higher rpm all over slipping the belt likely and the clutching and gas mpg go hand in hand. Likely will need to replace the tip rivet in the clutch weights with a heavier one.
..and thx
mile9c1
New member
I saw 12mpg once but it was a slow rail trail ride. You should easily be able to get 11mpg but it may take some jetting changes. I don't have that sled anymore so unfortunately I can't check what the jetting was.