Ok, for all the people who have bikes that are belt drive and those who know extensive information about pulleys, what kind of drive pulleys are you using? I have a pulley I bought from tractor supply and I think I screwed around and bought a pulley for fractional horsepower use only.
Let's talk pulleys
- Thread starter jazz2561
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What makes it fractional horsepower use only? is it made of soft metal or plastic? or is the belt groove too narrow? It should work as long as it's got a big enough groove for a decent sized belt and it's made from aluminum. Now if it's die cast metal or plastic I could see why they would recommand a low power limit.
Most of us are using tractor pulleys, those cast iron ones... but yes, a lot of us use lawnmower pulleys as well. It really depends on how much power you're dealing with and a stock 2 stroke china girl really don't make a lot of torque that can break stuff, but a heavily modified one is a different story.
Which engine are you using or planning to use? and will it be modified to make more power? Depending on the size of the pulley, and what part of the drivetrain it's going to be used on along with how much power we're talking about plays a big role in how strong it really needs to be. A small diameter pulley on the crank would be able to endure a lot more than a larger diameter pulley on the wheel where the torque at the center will be considerably more etc..
Also, do you have a pic of the pulley in question? I may be able to tell if it can hold up by seeing it and knowing what size it is.
Which engine are you using or planning to use? and will it be modified to make more power? Depending on the size of the pulley, and what part of the drivetrain it's going to be used on along with how much power we're talking about plays a big role in how strong it really needs to be. A small diameter pulley on the crank would be able to endure a lot more than a larger diameter pulley on the wheel where the torque at the center will be considerably more etc..
Also, do you have a pic of the pulley in question? I may be able to tell if it can hold up by seeing it and knowing what size it is.
The pully (sheave) groove MUST match the belt you are using. Look at the cross section of a 'V' belt. The angle/width and depth must match the pully (pully match the belt). A belt that is too narrow/wide will not ride properly in the groove of the pully and you'll loose a good portion of the gripping action. Just because the belt fits into the groove doesn't mean it is the same angle or depth.
Take a look at an industrial supply catalog such as Grainger and see what is offered as far as belt and pully sizes. Grainger usually has a page or two of good information about the products in that particular section of their catalog which will explain compatibility.
I don't run belt drives on my bikes but I've wondered why the guys who do haven't experimented with variable pitch pullys. The are adjustable and you can change the ratio between the drive and driven sheaves. http://www.grainger.com/product/Var...-/Ntt-adjustable+pulley?sst=subset&s_pp=false
Look at the list of pullys (part numbers) and you'll see the pully size correlates with belt size.
Tom
Take a look at an industrial supply catalog such as Grainger and see what is offered as far as belt and pully sizes. Grainger usually has a page or two of good information about the products in that particular section of their catalog which will explain compatibility.
I don't run belt drives on my bikes but I've wondered why the guys who do haven't experimented with variable pitch pullys. The are adjustable and you can change the ratio between the drive and driven sheaves. http://www.grainger.com/product/Var...-/Ntt-adjustable+pulley?sst=subset&s_pp=false
Look at the list of pullys (part numbers) and you'll see the pully size correlates with belt size.
Tom
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Thank for the replies, I'm running about 7 1/2 - 8hp. But where can I find a big rear pulley for the rear wheel
