[02rmksask]

Friend of mine just bought a 97 MM 600 and top speed is very low in my opinion. I drove beside him in my truck and top speed was 90 km/h. Sled hadn’t been running for quite a few years so we pulled the carbs and cleaned them and it fired up fairly quickly. The belt looks new on it and the rollers on the primary clutch are shot so he’s got new ones on order. Just looking for opinions on what would cause the top speed to be this low (I’m assuming it should go faster than that😁) And one more thing, it has a 2 up seat on it so would something be different on this sled (setup for trails?) compared to a normal MM 600.

 

[02rmksask]

Sorry guys. Wasn’t thinking straight before. Never thought about chain case sprockets. Most likely geared for 2 riders 🤦🏻‍♂️

 

[BC_Dan]

My 550 two-up will do 130+ kph (85 mph) pretty easily. What RPM is he running at the slow speed?

I would make sure the primary is shifting out all the way. Take a magic marker and make a mark on the primary sheave in a line from the center to the outer edge. Then go ride. Hit wide open a few times and see how much of the mark is rubbed off by the belt. If there's a good bit of mark left, it may be time to go through the clutches and make sure center to center on the primary is set to spec. Make sure the belt deflection and primary to secondary offset is correct as well.

 

[kccats]

That does seem a bit slow if the rpm is down, what is your compression?

 

[snowmoer]

The Mountain Max were geared lower for deep snow. But, that is a little on the slow side. My 96 600 tops out at about 110 kph on hard pack. Agree with Dan on things to check.

 

[02rmksask]

Thanks for the replies guys. Marked the clutch this afternoon and took it out for a bit. Engine rpms were 8000 wide open but belt is only travelling half way up the primary clutch sheaves. What should a guy look at next?

 

[BC_Dan]

Time to get the clutches off and give them a bath and some TLC. I'd get both of them apart and check for broken/worn parts, especially a broken spring in the secondary...

 

[kccats]

Also check the center to center on the clutches
If the motor has pulled back on the PTO side it will make the belt too Loose!

 

[Vipertriplexxx]

It probably has the original clutch springs in it. When you go through the clutches and align them, replace the primary and secondary springs, they are cheap.

 

[Vipertriplexxx]

Belt can be a problem also, I replace mine often just for performance reasons.