redneck fun....
 

well got a wild hair....

I have been playing around with the idea of playing with my mower and making it faster. it is a simple belt driven mower and it is 9 years old and was $700 brand new.

the idea is that there is a front pulley and a rear pulley. making the rear pulley smaller increases the speed (but decreases torque)

I had an 8.75 inch pulley on the rear and now it is a 5.44 inch pulley. obviously the belt had to change.

the difference was 60% so it should have gone that much faster. I used my handy dandy GPS to track my speed. the numbers below are actual speeds by the GPS. also realize that it probably isn't as accurate at lower speeds.

Gear____8.75____5.44
1_______1mph___1.8mph
2_______2mph___3.4mph
3______2.9mph__4.8mph
4______3.3mph__5.4mph
5______4.2mph__8.3mph

R______1.6mph__2.4mph

https://i44.tinypic.com/sp9do9.jpg
pulley and belt (I ended up going with a different belt)

https://i39.tinypic.com/2lj3uj6.jpg
this is the original pulley and the new one side by side

my goal was to have fun with it and to get it faster but to still have it usable as a mower. I used to mow in 4th gear. now 2nd gear is pretty much where 4th gear was. I can still mow with it and have a little fun. it is kind of like my redneck 4 wheeler.

just for fun (and because several people at work said I would be racing it within a year) I put a number on the side of it.

I know this has nothing to do with gas savings but I figured we could all use a good laugh. it was a fun little project and relatively inexpensive. I like to pick on the rednecks. little did I know that I was one of them too..... lol

https://i42.tinypic.com/fbd6x.jpg

https://i39.tinypic.com/8xri0x.jpg

the beef

Re: redneck fun....
 

You could also use an idler or belt tensioner if necessary.

I bet a bicycle speedometer would be easily adapted.

Re: redneck fun....
 

Cool project. And you picked the right number, too!

Re: redneck fun....
 

400 Posts! WOOT!

Re: redneck fun....
 

Make sure that speedometer also has an odometer- that way you can start a gas log for this vehicle :D

Re: redneck fun....
 

just for kicks, I looked up bicycle speedometers. the dial/mechanical ones go up to 40-50mph so I think I wouldn't be able to tell much as I am still under 10mph.

I think there would also be an issue since my tires are 18.5" diameter. not sure you can set the tire size on even the digital ones.

I actually bought an assortment of pulleys. I currently have 5.44", 4.5", 3.75", 3.25", and an idler pulley. I wasn't sure what i was getting into so I kind of went crazy. I have a lot of spare parts.

I can't make it faster and still use it as a mower. eventually I will retire it and then I may play further.

this project was supposed to be fast and fun but ended up costing me ~$150 and about a month (not all working on it).

given that it is a 12.5hp mower, I would assume that it is actually pretty efficient. I use about 5ish gallons a season mowing grass. my yard is rather small.

Re: redneck fun....
 

Digital bicycle speedometers that I've used can be set for almost any size tire and would certainly work with 18.5" diamter tires.

Re: redneck fun....
 

Just mow in 1st gear. I remember the tractor my dad had when I was a kid, we always mowed in 2nd, because 3rd was way too fast. I imagine one could make it much faster, you could run it into a tree in third gear, and it would not stall out, it would just sit there spinning its wheels. That would be fun to mod faster. Dad still has that tractor, but it doesn't run anymore. Its an antique, and he still thinks someday he'll get it running again.

Re: redneck fun....
 

Next thing, Larry The Cable Guy and his TV crew will be at your door.

Re: redneck fun....
 

a bigger problem than mowing in first gear is reverse. reverse is pretty fast right now so I don't want to speed that up either.

as far as the speedometer, not sure how I would mount the speed pickup. it may be something I revisit later. that would be funny.

larry would probably opt for the guys that actually do race these things. those guys are nuts. just for S+G I looked up how much an actual racing lawnmower costs. I found one on ebay for $3500. that pretty much ended my lawnmower racing career.