I want to look into making a stupid fast mower

Hey everyone I'm new here I'm wanting to do a hellacious pulley swap to my simplicity mower... It's a standard 6 speed I, don't have any specs on it yet, I still have yet to find a model number on it. The pulleys I have lined up are (prepare yourself) front 14 inch and rear 2.5 inch... I know that will be probably too fast but I'm a big time adrenaline junkie that loves speed lol. My question is, how fast would I most likely be moving? Thanks guys! Once again, safety is not a concern because if I do go fast with it, I'll have full gear on

Can you fit a 14 inch in there?  I thought I was pushing it with a 9 inch on my craftsman?

14" is pretty big, I would think clearance issues would be a bugger. Also 2.5" is too small to have any belt grip, espesially with that aggresive of a pulley swap. Also if you did somhow manage to comfortably fit a 14" pulley in the front, you're going to want to prep your trans for that kind of input speed. What kind of engine are you running?

Sooooooooooo

14/2.5=5.6

3600x5.6=20160

20160/13.5=you know what screw this imma let a calcuator do it from here



Yeah, I hope you wear gear. And I calculated this for a governed mower. Good luck...

Chances are that your pulley will be wider than the frame. You'll definitely need a custom front axle and direct steering to go much above twice or three times the original speed.

The art isnt just making a mower fast, it's making it able to handle the speed.

MatthewD wrote:

Chances are that your pulley will be wider than the frame. You'll definitely need a custom front axle and direct steering to go much above twice or three times the original speed.

The art isnt just making a mower fast, it's making it able to handle the speed.

Very well said. I can just see the death wobble!

Wait wait wait....how come we have 20,000rpm in the speed calculator?  I don't know the exact specs but I 14" front to 2.5" rear pulley sounds way to high to work. I would think a 2.5" rear pulley would have slipping issues. Probably you don't need more than a 2-1 ratio. Stretch did a highway run and got 60mph or so, forget what ratio he used but even his setup was too high and he couldn't get into high gear with a 20hp v twin.

-Oh, and welcome!

Sorry for double posting, but here is the real worlds fastest lawn tractor. Bobby Cleveland, using a modified briggs v-twin and 820 transaxle (pretty sure) went 96.529 mph. There are two faster records, one from honda at about 116 mph and some other guys at 134 mph, but these do not use lawn mower parts.

I think the issue is, the only people who have an "official" lawn tractor speed record are guiness world records. And what they care about is having impressive sounding records....not how many lawn mower parts you use. That's why atltf.com should form their own sanctioning body and have our own official records with more official rules to keep things in check. But anyway, that's getting off topic. Here's a video.

That was sooo coool!! I bet that transaxle was screamin!! Thanks for sharein mr modified.

Wow....

hmmmmm salt lake racing up the road, now you got me think mr.modified.

That is gonna be sketch-fast I hope the pulley fits