Shorter drive belt

[CHEESEMAKER]

Originally Posted by Heliarc

Oh sorry.I misread you earlier.You wanted a stock number.I do not have that.The HP3004 is a shorter belt by about an inch.It will give you more climbing ability at the expense of top speed.

Thank you for clarifying that for me. I'm in the process of getting some carts running again for a Outdoor School program I volunteer at. There is a couple steep hills at camp we rent, but it usually isn't an issue. The belts are old and worn, so I think a stock belt will work just fine for our needs.
I'm only gonna be able to get two of the carts running this year. The other two are having some other "issues" like carb, rebuild or ??. And I got a fifth one that I'm calling the "Mystery Machine." Once I get pictures of it, you will know why I call it that.

[Heliarc]

I had the stock belt on mine years ago before I actually owned it, and though slow, it would still pull some pretty good grades.After I came to own it I had it off in the trails all over the place with the belt pretty badly worn.It would pull most of it even still.I don't think you'll have much trouble.

Definitely want to see some pictures.

[Madman415]

A shorter belt will not give you more torque, it will only get you to high gear sooner.

[Heliarc]

Originally Posted by Madman415

A shorter belt will not give you more torque, it will only get you to high gear sooner.

A shorter belt will reduce the "gear" ratio and will absolutely deliver more torque.

[1fast67]

The shorter belt will hold it into low gear longer thus giving it more torque to climb hills ect. You will lose a little top end speed but not enough to notice.

Sent from my LG-P999 using Tapatalk 2

[Madman415]

ok so you put the belt on, its sits snug on the drive clutch and sits lower inside the driven clutch because it's shorter. The last thing you want to do is have the belt "lower" in the driven clutch if you want to pull. As soon as you accelerate, the front clutch will start closing thus pulling the belt deeper into the driven clutch then it would be with the stock belt. So now that the driven clutch is open further then it normally would be, being in a higher gear, how does that give you more torque?

I've always had EZGO's, so maybe others work differently with different clutch set ups, I don't know. What I do know is that the key to getting torque from an EZGO is to get the rpm's to 2,200 before it even moves, belt sitting at the top of the driven clutch. At 3,500rpm the belt is 1/4" down inside the driven clutch. 4,000rpm the belt will put the clutches in "High Gear" quickly if there is no load. Governor reduces RPM's to 3,000 to cruise. Belt up high on drive clutch and down to the max on the driven clutch. When I played the shorter belt game, I didn't get to 1,500rpm and was already moving along and at 2,000 clutches where in "high gear" state. The Robin engine's torque curve is at 3,200-3,800rpm unless you play with the governor it will continue to pull up to 4,200rpm.

Just like a bicycle, small gear up front, big gear in back, easy to pedal = torque you can ride up a hill
big gear up front, small gear in back, you go fast but you will struggle on a hill because it's too hard to crank the pedals.

[Heliarc]

That might be your problem.I don't have a governor anymore.I think most of the people on here don't either.Regardless, my Marathon is undeniably faster up hills.With the old belt there were a few times I thought I'd have to get off and push while hand throttling it to get up a hill.Now it goes up just fine.I can't really explain how it works, and I understand your point with the bicycle example, but for some reason, it works.It might be that low ranges are higher, but high ranges are lower.

[Madman415]

Is it that it is climbing better or is the engine speed higher giving more power? The only way I can see a shorter belt working better is if the Drive Clutch is just about shot and the Driven clutch is stronger.

Are you running stock clutches?
When you say you eliminated the governor, is the throttle cable connected "directly" to the carb or is it turned up all the way?
I never eliminated the governor completely because I've noticed that with it intact, the engine only gets the fuel it can burn thus giving me awesome fuel mileage. Is it a great benefit to eliminate it completely?
What do you do with the weights inside the rear diff?

[Heliarc]

The first question, I'm not sure how to answer.It's just working better on hills is all I can say.Before the change it was lugging so badly it would hardly run and struggled badly.Now the engine is at a reasonable RPM and cart speed going uphill is higher as well.

I'm running stock clutches with no modifications to them.

As far as the governor, it was never hooked up when I got the cart.I just removed the remnants of it.The cable was cut or broken off so I just removed all of it.So honestly I wouldn't know what benefit it brings you to disable it other than you can get more revs, but you also have to be careful not to over rev it.

I haven't messed with anything in the rear diff so I wouldn't know what you mean there.

[Madman415]

I would like to see someone post a video of the clutches themselves operating with a shorter belt. I'm so interested in this because I've tried it and mine actually was worse on hills. You may be right, it may be because I still have the governor hooked up, but lemme ask ya, Do you have to back off the gas pedal and hit it again to climb hills or is it just "down shifting" on it's own with ur foot to the floor board?