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Discussion Starter #1
Ok so I have been doing alot of research but Iam stumped and need help so I got started on this project to change my pulleys on my lawn tractor to make it go faster.

my engine id is

281701-0412-01

and I found out from brigs website that my crankshaft is a

1" dia. x 3-5/32" keyed crankshaft

ok so then I went to this site to order some pulleys

http://www.mfgsupply.com/MowerPullHDCast.html/mv_session_id=FWVp8BJM
**PLEASE TAKE A LOOK**

So anyways I researched and from what Ive read I understand you are to change out the engine pulley for a larger one about 3 inches to get more speed?
and make the transmission pulley smaller 2 inches smaller ? and since I have now a double engine pulley I could just take it out and put a single engine pulley in right? well Iam not sure.

So I asked on yahoo answers if this could be done to myne and a kind fello replied and said this

"You will not be able to do this and I will tell you why.... The Briggs and Stratton engine uses one size pulley for each engine size and the crankshaft sizes ar not interchangeable. However you could get the larger pulley, and after removing the old pulley, and, by cutting off the old pulley from its shaft, weld the new pulley to the old shaft (after cutting the new pulley off its shaft, of course). I did the same to a large home brew tractor using two old 46" MTD decks that I welded together and got the belts sizes I needed from O'Riely auto-parts. They sell belts from 14" to 10 Feet in one inch increments."

Ok thats great............. Not but then someone else told me it could be done be done.

and they said to try to see if I could mount my double pulley up side down. havnt tried it yet but ..

I really need help on what to do anyways the site I first posted with the pulleys if one of you could be so kind to help me out and tell me what 2 pulleys I should order (transmission and engine) that would be the measurements are confusing me and I would really like to do this so I can get my lawn tractor faster.

http://www.youtube.com/watch?v=w6A456EaDkI

here is a video on youtube of my lawn tractor for a better look at it please help.

ALSO I have phoned many companies which sell pulleys on the internet but everytime I call no one knows **** ALL about engines or anything.

The thing here is I know what I want a 6innch pulley in the front and a 3 inch in the back.
and I dont know which one to order because I dont get the measurements or anything is there any possible way someone on here could find me the exact part I need if not does anyone know of any stores like tsc or anything in canada that could help me???
 

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The voice of reason !
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I have never heard so much BS in my whole life !

What the heck are you getting into young man.

OK first how much more speed are you after and Yeah ok you go ahead and try to flip the double pulley over then send the guy who told you that an email and tell him he full of BULL.

Do you have a hydrostatic trans or gear driven ?
 

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Discussion Starter #3
I have never heard so much BS in my whole life !

What the heck are you getting into young man.

OK first how much more speed are you after and Yeah ok you go ahead and try to flip the double pulley over then send the guy who told you that an email and tell him he full of BULL.

Do you have a hydrostatic trans or gear driven ?
Gear Driven its 6 speed
 

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The voice of reason !
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Gear Driven its 6 speed
Yeah I just saw that pretty good vid you made.:fing32:

Ok first off what are you trying to do race, pull, drag what ?

Or are you just having fun ? And I swear if your just doing this so you can put a dumb video on Youtube showing how high you can do wheelies I'm comming to you're house a slappin some sparks out of your head LOL kidding.

But really depending on what you want to do will dictate what size pulley you use so what do you think you would like to do ?
 

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Discussion Starter #5
Yeah I just saw that pretty good vid you made.:fing32:

Ok first off what are you trying to do race, pull, drag what ?

Or are you just having fun ? And I swear if your just doing this so you can put a dumb video on Youtube showing how high you can do wheelies I'm comming to you're house a slappin some sparks out of your head LOL kidding.

But really depending on what you want to do will dictate what size pulley you use so what do you think you would like to do ?
Ok first to answer your questions I want it to race/ have fun

I swere to you its not about making gay videos on youtube.

I love working with engines and stuff like that.

I thought this would be a fun project to do.

It turned out to be a little harder then I thought on the fact no one knows anything and cant help me.

I want a 6inch in the front and a 3 inch in the back but I dont know how too order them because I dont know if they will fit my crankshaft.

now if you could be so kind. HELP ME!!!! lol

Please dont be offended I cant help it that I dont get everything right away.
 

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The voice of reason !
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Ok first to answer your questions I want it to race/ have fun

I swere to you its not about making gay videos on youtube.

I love working with engines and stuff like that.

I thought this would be a fun project to do.

It turned out to be a little harder then I thought on the fact no one knows anything and cant help me.

I want a 6inch in the front and a 3 inch in the back but I dont know how too order them because I dont know if they will fit my crankshaft.

now if you could be so kind. HELP ME!!!! lol

Please dont be offended I cant help it that I dont get everything right away.
Not a problem Bud.

Ok first lets look at what you have stock from your video i would say your trans pulley is about 7"-9" in diameter , and your front is probably 3.5"-4.5" ?

Does this sound about right ?
 

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Tractorman15 if you would post the diameters of the pulleys that are currently on the tractor along with belt sizes, not the length so much as the width, it would help a lot.

Going to a 6" diameter pulley on an engine to a 3" on a transmission seems to be a very large speed increase to the transmission input shaft unless you have a very low geared drive train.

There are a lot of knowledgeable people on this forum that have "Been there, done that" and will be able to give you some good advice. Just on the surface you may be running into a problem of not enough power to make this work if the ratio is too extreme.

As Ranchkingron said, these folks will need to know what the intended use is. Really makes a difference.

Mike
 

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Discussion Starter #8
Tractorman15 if you would post the diameters of the pulleys that are currently on the tractor along with belt sizes, not the length so much as the width, it would help a lot.

Going to a 6" diameter pulley on an engine to a 3" on a transmission seems to be a very large speed increase to the transmission input shaft unless you have a very low geared drive train.

There are a lot of knowledgeable people on this forum that have "Been there, done that" and will be able to give you some good advice. Just on the surface you may be running into a problem of not enough power to make this work if the ratio is too extreme.

As Ranchkingron said, these folks will need to know what the intended use is. Really makes a difference.

Mike
ok maybe your right I think I jumped the gun on this thread I should probally take out both pulleys and give yall the specs to better help me.
 

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Discussion Starter #9
Not a problem Bud.

Ok first lets look at what you have stock from your video i would say your trans pulley is about 7"-9" in diameter , and your front is probably 3.5"-4.5" ?

Does this sound about right ?
my crankshaft is a

1" dia. x 3-5/32" keyed crankshaft

I know that 100%

but I think the transmission probably sounds right.
 

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The voice of reason !
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Tractorman15 if you would post the diameters of the pulleys that are currently on the tractor along with belt sizes, not the length so much as the width, it would help a lot.

Going to a 6" diameter pulley on an engine to a 3" on a transmission seems to be a very large speed increase to the transmission input shaft unless you have a very low geared drive train.

There are a lot of knowledgeable people on this forum that have "Been there, done that" and will be able to give you some good advice. Just on the surface you may be running into a problem of not enough power to make this work if the ratio is too extreme.

As Ranchkingron said, these folks will need to know what the intended use is. Really makes a difference.

Mike
I think you're right Mike that is a huge jump in gearing,

I think we may have to give this young man a small bit of gearing basics 101 ?

What do you think ?

Gotta had it to the kid he's got a good attitude about why he's doing it.
 

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You can also just put a smaller pulley on the tranny and leave the engine one alone..if you try putting a larger one on the engine,it will likely interfere with the idler/clutch pulley and any belt gaurds or guides will have to be removed as well--why re-engineer the whole thing if you didn't have too?..larger rims and tires will increase top speeds without making any changes to the drivetrain too..there are other ways to increase the top speed by making a jackshaft with two pulleys mounted on pillow block bearings in the center of the tractor and use 2 v-belts instead of one long one direct to the tranny--this allows all the stock parts to remain unmolested ,and will have the advantage of wearing only one belt out that is shorter & cheaper than a long one is..(and they will burn up fairly quickly when your using one as a clutch with higher gearing for more speed!)..
 

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The voice of reason !
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You can also just put a smaller pulley on the tranny and leave the engine one alone..if you try putting a larger one on the engine,it will likely interfere with the idler/clutch pulley and any belt gaurds or guides will have to be removed as well--why re-engineer the whole thing if you didn't have too?..larger rims and tires will increase top speeds without making any changes to the drivetrain too..there are other ways to increase the top speed by making a jackshaft with two pulleys mounted on pillow block bearings in the center of the tractor and use 2 v-belts instead of one long one direct to the tranny--this allows all the stock parts to remain unmolested ,and will have the advantage of wearing only one belt out that is shorter & cheaper than a long one is..(and they will burn up fairly quickly when your using one as a clutch with higher gearing for more speed!)..
Didn't You just say why re-engineer it and here you are telling him to use a jackshaft and pillow blocks etc.etc. thats why I ask him to measure everything and we can give him some tips that will help not hurt.

Your idea of going smaller on the trans input shaft is perfect I think, but we don't want to go too small at the same time.
 

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Discussion Starter #13
Didn't You just say why re-engineer it and here you are telling him to use a jackshaft and pillow blocks etc.etc. thats why I ask him to measure everything and we can give him some tips that will help not hurt.

Your idea of going smaller on the trans input shaft is perfect I think, but we don't want to go too small at the same time.
So you want me to remove both engine pulley and transmission pulley and belt and tell you the measurements?
 

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The voice of reason !
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So you want me to remove both engine pulley and transmission pulley and belt and tell you the measurements?
Do you have a tape measure and or a good size caliper ? and measure the width of the belt length is not important.

All we need is the best measurement you can give us, but you and we will need to know what your trans input shaft size is to help you find one that works also is it splined, smooth, star. etc.

as far as the engine pulley do the best you can but if your going to pull it off anyhow then you can get exact sizes.
 

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Yup, I think it's schoolhouse time for understanding power transmission.

Tractorman I applaud your interest in modifying a tractor to suit your needs. Don't think you need to remove the pulleys from the tractor, just take a tape measure and check how far across the face (diameter) each pulley is. From this a ratio calculation can be done. Then run the tractor as it is and find out how fast it's going. Next step is to decide how fast you want it to go while keeping in mind the available horsepower and capabilities of the machine. With these numbers it's a short walk to determining the pulley sizes you need. Good chance you will need to change just one pulley as has been suggested.

Remember the rule of thumb that it takes four times the horsepower to double the speed. Not a set in concrete rule but it's usually pretty close.

Mike
 

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Yup, I think it's schoolhouse time for understanding power transmission.

Tractorman I applaud your interest in modifying a tractor to suit your needs. Don't think you need to remove the pulleys from the tractor, just take a tape measure and check how far across the face (diameter) each pulley is. From this a ratio calculation can be done. Then run the tractor as it is and find out how fast it's going. Next step is to decide how fast you want it to go while keeping in mind the available horsepower and capabilities of the machine. With these numbers it's a short walk to determining the pulley sizes you need. Good chance you will need to change just one pulley as has been suggested.

Remember the rule of thumb that it takes four times the horsepower to double the speed. Not a set in concrete rule but it's usually pretty close.

Mike
I have a double engine pulley it has a smaller wheel at the top where the belt is and a bigger one on the bottom for iam guessing the the blade was?

how would I find out how fast its going?
 

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The voice of reason !
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I have a double engine pulley it has a smaller wheel at the top where the belt is and a bigger one on the bottom for iam guessing the the blade was?

how would I find out how fast its going?
We will explain that when you get the sizes but basically you divide the diameter of the trans pulley by the diameter of the engine pulley, this is dirty math at it's best but it will give you an idea of how it works.
 

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I have a double engine pulley it has a smaller wheel at the top where the belt is and a bigger one on the bottom for iam guessing the the blade was?

how would I find out how fast its going?
gps..
 

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Im not sure about all that stuff, but heres some pics of mine. 6 inch front pulley, 3 inch rear, both from tractor supply. I get 25-30mph.[/ATTACH][/ATTACH]
there on a cub cadet 1015 with a peerless 6 speed. you cant flip the front pulley, its bs. you will have to mesure for a new belt becouse the old ones not going to fit once you modify it. I use tractor supply for all my belt and pulley needs.
 

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