1987 yamaha g1 w 440 arctic cat motor

[snow camo]

Not sure of anyone has tried this but curious if a solid belt sproket would be better than the secondary stock clutch.

[CharlieN]

You would have no variable ratio drive, that would ruin any chance of usefulness.

[snow camo]

I Have seen one other person do it before and it helped w only top end speed. Im looking for low end tourqe and mid range pull. Just having problems getting things to work right.

[slonomo]

Not sure what you're question is? You want the cvt belt drive system, this allows you to have low end power and a high top speed. This is why snowmobiles and atv's use the same type of setup. If you aren't having luck getting it to run right it might be a mechanical problem. Either the engine is out of tune, or the belt and/or clutches are worn. I'd guess you should top out at around 35 mph with a good running 440. You are limited to what the gear ratios allow, and that's about it. You should, however, have tons of power.

What exactly have you done? Where are you in the project? Is the cart running and driving?

[snow camo]

The cart runs and drives. It will do about 35 mph. I t just does not really pull that hard on the bottom. I have it lifted about 10 in with wide tires on it. I recently removed the rear axle cause i need to rotate the axle forward cause im spilling out the vent tube

[slonomo]

Are you running a stock sled clutch? If so, I wonder what rpm it is engaging at and also condition? What about the belt, good condition? You might be getting some slippage?

Some sled engines are tuned for high rpm power output, this could be the case. If engagement is at say 3500 rpm, and power doesn't peak until like 7500 rpm, that's a big gap. To get good low end grunt you would want peak power down in the 4000 rpm range with engagement in the 2500 rpm range.

Might need a vtwin four stroke big block kit for that kind of low end.

[CharlieN]

I would expect if the existing drive were well tuned this cart should be spinning wheels at low speeds.
If you do some searches online about tuning snowmobile drives you can get an understanding of what needs to be done.
Start with belt width and length.
Does the belt start out at the top of the secondary pulley?
Is the belt a snug wrap around the primary pulley so that when it engages it starts at a small diameter there?

You may find if the belt is not a good fit at this time, just correcting this will give major improvements as well as possibly more top end.

Once the belt fits right then tuning springs and clutch weights will make the cart drive better as well.

[snow camo]

The belt i am using does fit snug and is at the top of the secondary cluth. I changed ths secondary spring to a stifer spring and i got better mid and peak power out of it. The primary is still stock i have sii have not touched it yet