Lawnmower racing

[hotroddal]

hey i am just wondering if anyone else on here races lawnmowers, im building a racer right now and its pritty sweet , its got an 8 hp tecumseh horizantel shaft engine with a belt that goes to a jackshaft that goes to a chain that drives the rear wheels, its also got electric start and get this this thing only weights in at 130lbs,and its only 4 and a half feet long, i tookk off every thing that i didnt need, every extra bolt, every extra peice of metal that i ddint need, changed the gearing, and this thing has no trannsmition its just a direct drive so this thing is gona be crazy fast, i know this does not meet the requirements to race it in an actual vent but i just built it to have fun on and rip around town on, and also i custom built a exhaust system thats all chrome, its got a straight pipe about 6 inched long then it sorta couved downward.

[Wickedfinger]

Killborg used to race them .... he hasn't been on for quite a while though ....... mis ya you mean bastid!.

[1984kxtTECATE]

I want to get into the sport, it would be fun hauling arse down the neighborhood doin 40-50 mph, I have a donor mower, I just dont have the money, lol.

[dizasterzrfun69]

well i have an old MTD coast to coast mower that i started to tear apart for this. I was planning on popping an '85 250sx engine in it, but now i'm having 2nd thoughts. the engine is alot nicer looking than i thought and so i might just put this junk 250sx back together and kinda "restore" it as i go. Any ideas how to get power from a 11hp briggs and stratton vertical shaft engine to the rear wheels? I dont know how to do it just because the shaft on the engine runs up and down and the rear axle obviously runs left and right, any ideas?

Kevin

[MTS]

well i have an old MTD coast to coast mower that i started to tear apart for this. I was planning on popping an '85 250sx engine in it, but now i'm having 2nd thoughts. the engine is alot nicer looking than i thought and so i might just put this junk 250sx back together and kinda "restore" it as i go. Any ideas how to get power from a 11hp briggs and stratton vertical shaft engine to the rear wheels? I dont know how to do it just because the shaft on the engine runs up and down and the rear axle obviously runs left and right, any ideas?

Kevin

belt drive!

[dizasterzrfun69]

belt drive!

Do you mean just run a belt to the rear transmission? I was thinking that, but it seems like 30-40 m.p.h would blow the tranny.

[hotroddal]

ok guys i have taken it out for a spin and i can tell ya it is crazy fast and has a ton of torque, i mean you can be cruzin down the road and burp the throtle and it wil do a small wheelie and will burn out on tar.

[MTS]

Do you mean just run a belt to the rear transmission? I was thinking that, but it seems like 30-40 m.p.h would blow the tranny.

you can always rip the old tranie out...what ever it is and run a ski-doo style clutch system to a soldid rear axel that has a belt or chain drive systm...kinda hard to explane

[03 ORANGE SHEE]

they drag them at my local track, alot use a shee motor with drag pipes or a 250r motor, they haul butt!!

[70binder]

how's 45 confirmed mph sound?


looks like crap, but the things fast as hell (and sounds like a harley!!!)

also it's sitting at about 19hp on a 12hp stock briggs.

[hotroddal]

70binder, what all did you do that thing i want some details.

[70binder]

70binder, what all did you do that thing i want some details.

haha sure.

regeared it from 4"/11" to 10"/5" pulleys, converted to 5/8" belts over 1/2", dual tensioner pulleys (to handle the 1960's chevy hood spring for a tensioner, and believe me, you need those 40 lbs of tension)

cleaned up/polished intake, carb, and int/exh ports

flow-maximized exhaust (yes its black iron pipe but all pipes and fittings are streamlined internally

shaved and built head (filled the low-comp wedge machined at the factory with mig'd aluminum block (feels like 9:1 comp vs 6.7 stock)

93 octane

el-cheapo plug that's been in there since i got it (gapped wide as hell and runs perfectly fine)

ratchet-style shifter (minus the ratchet... hope you can count gears)

with the stock tranny, 1st/2nd gear are only about 12% apart in gear ratios, 3rd gear takes 30mph with redline. not counting 4 and 5.... 1-2-3 are close ratio, 3-4-5 are WIDE ratio)

2" exhaust tip out of Trader Horn

seat was lowered 5", wider rear axles were put in along with 20-10x8 cheng-shin turf tires (quiet on the road, mostly where she ran, although still pretty peppy in the dirt/grass) in back, and 15-6x6 goodyear ribs up front

foot thottle, used oiled hardwood and plactic-coated self-propelled clutch cable

no air cleaner lid

pullstart

weighs about 140lbs, it's a heavy frame

also it doesn't have brakes, didnt have any pad left so i ripped em out, i just downshift and let the 300cc beast take care of it

anything else you want?



EDIT:


transmission is actually stronger than the trans in a 200x, at least mine is. gears are harder and look like they mesh better, not to mention they're alot wider.

if you want a bulletproof rearend (good for like 40hp) i have an older 3-spd that converts vert shaft to horiz. shaft, gear ratios are 9:1, 6:1, and 2.5:1

also have a 2-spd unit, gears are 1" wide, ratios are pretty crawly at 11:1 and 8:1

i have several spare briggs blocks (11, 12, 8hp) and a 16hp twin sitting, all not in use.

[1984kxtTECATE]

same, I want to mod out our regualar lawnmower to make it look like a sleeper, lol.

[hotroddal]

70 binder, im just wondering how is your takeoff, because you saud it goes 45 and you geared it to go faster, so does it take a little while to gain speed or is it just like quik to get up to speed, ive recently aquired a 1960 gambles rider and im going to make this one an all out racer, im going to race it in FX races.

[BIGCRIP28]

that thing must blow your ear out with that pipe pointing at your head