Worlds First Fully Automatic Race Mower 20hp Twin True Dual Exhaust

[hixman561720]

i see you made an auto mower fast im guessing it has a variable speed pulley what exactly did you do to make it go like you wanted im working on one just like it and i can make my mind up what to do

[metallicasg100]

nice mower, sounds awesome, check out my video of my dual exhaust v-twin mower

[drDROID1]

Legit pipes

[countryboyps3]

nice true duals

[noledroByrreK]

thats gonna be a hot frame

[HybridIce02]

hello, i have one question for you. I have been making race mowers for a while the easiest way possible. Belt and pulley swaps. For some reason tho on my hechinger i cannot seem to get it right. i have a 6in on the front and a 3 on the back and am stuck on belts since my clutch is in the center and both belts have to be perfect to get all gears right. im stuck between a 51-53 on the front and a 37-39 on the back. any suggestions?

[cobrafied]

@HybridIce02 all i know is you have to have matching pulley widths with your belts, or your belts will break. I wasnt around for the race last year, and 2 years ago I was having the same issue as you I believe, although I plan on buying a centrifugal belt clutch for this years. Good luck.

[alecm94]

@cobrafied Thanks!

[alecm94]

what brand of paint did you use on the rims? cuz i want them THAT color lol

[cobrafied]

@alecm94 Home Depot look for Chrome Spray Paint.

[TricksAtHome]

I hav the same mower can u give me detail on how u did it?

[cobrafied]

@TricksAtHome burn holes through the metal frame with torch, run plumbers pipe and weld good luck

[cofferson]

I really wanna make one of these fuckers :P wheres the best place to learn what you need to do???

[cobrafied]

@cofferson your imagination. and google might help ;)

[cofferson]

@cobrafied oh if i make one it'll be awesome hahaha but yea i guess google is a good place to look. thanks :P

[suchfunstuff]

Getting that idle down is easy. Just look for the smaller spring going from the governor arm to a stationary tab. Bend the tab so that it has less tension (toward the gov. arm). You could just remove the spring altogether and set your idle with the throttle stop screw.

[HemiT426]

how do you get the motor off with the exhaust welded like that?

[cobrafied]

@HemiT426 Good question, id have to sit and look at it, might be able to reheat and turn the headers cause theyre welded to plumbers pipe pieces which are threaded.

[300exrider81]

i was told if you would stright pipe a 20 hp briggs it wouldnt run right is that true?

[cobrafied]

@300exrider81 . we've straight piped a few mowers in our races and they all run flawless. i heard that too, until we did ours without listening and it was fine. I even drilled 1 inch holes with a step drill bit around the airbox for any possible free'er flow. All is like i said, fine. A bigger jet wouldnt hurt though, mower repair shops may help u with that (i havent even looked into larger jets)

[alecm94]

where'd you get the rims?

[cobrafied]

@alecm94  "chrome" spray paint, its not quite chrome but looks nice.

[Z3CHYD]

now THATS sweet :)

[creamyfilling102]

ohh yeah the briggs I/C series. perhaps the best engine ever built. we've got the 14.5 horse and it runs like a champ. unfortunately the Murrey Deck is a piece of shit and it doesn't cut very good. when that mower goes to hell, i'll probably soup it up like yours.

[VTeamRacing88]

the exhaust on it runs through the front axle which is welded solid to the frame so it will not have an issue with flexing.

[VTeamRacing88]

have you tryed taking the butterfly out of the carb? i have had that issue with one of my engines and that was the problem. there are the 2 screws that hold it in place and there is a little bit of room for movement. i would try that and see what happens. if that does not work try to take a small file and make it so it will work.

[cobrafied]

@VTeamRacing88 we replaced the carb gasketsbut haven't "removed" the butterfly, how exactly does that fix the idle I think I don't quite understand. Yours sounds perfect I can't wait to go back home this summer and fix the idl, I'm in love all over again with the sound.

[VTeamRacing88]

you need to lower your idle on that thing!  lol

[cobrafied]

@VTeamRacing88 you noticed, yes. It won't calm down though, the idle has been turned down but the idle arm floats off resting point and we gotta look into it further, your ideas and pointers are appreciated if this issue sounds familiar.

[pedekiller]

i was like, nice, till he pulled the hood and it was the opposed twin, then i was like OMG EPIC WIN!!!!

nice rig dude! bout to start my own build but i'm a noob and i'm stuck with a one lung 12hp

[cobrafied]

@pedekiller yes, craigslist has gold awaiting us mower tuners. Buddy if you work on getting the smallest pulleys u can find for both front and rear, your 12hp will rocket. My friend swapped a 18hp twin in place of his one lung 12, so its up to you to be stuck!

[pedekiller]

@cobrafied thanks man.

got my build going. 11hp rover rancher, does about 30kph with a 5" engine and 3" tranny pulley. got to weld the diff yet and adjust a few other little things (require a slightly smaller belt) and it'll be all set to go but as of now...it's soo much fun!! poor mans ATV :D

[cobrafied]

Yeah much more sport inhaving no suspension, and drifting on gravel is really fun

[420witchdoctor]

I'd turn it into a wheelin machine.

[cobrafied]

@420witchdoctor we are trying to add an offroad event to the list of challenges, the track is made we just need approval.lol

[420witchdoctor]

@cobrafied AWESOME!

[tylan13chuck]

its a yard machines. How did you custom paint it

[cobrafied]

@tylan13chuck spray can and pinstriping. Lol id like to gowith a different paint scheme this year since we didn't win the show class, its a semi metalic paint. Schucks/krager/checkers carrys decent dupont car paints in spray cans.

[qxvmx]

the header pipes run through the articulating frame assembly????? or did you make it solid???

[cobrafied]

@qxvmx the front is welded so the body doesn't move, torched through the frame, ran the pipe through, welded thepipe to the frame for support. This way we can lower it without possible clearance issues & we didn't have to cut our blackpipe, just plug and play..minus all the welding to the header and frame.

[dirtscooterer06]

also is that an mtd wizard?

[cobrafied]

Not sure, yard machines/mtd somethin or other... I dont remember.. I stripped all the emblems off the first day I got it.

[dirtscooterer06]

hey man can you put up a video of what the pulleys set up undereath looks like i would apreciate that thanks man

[cobrafied]

2" rear pulley (not the drive pulley) stock front pulley i believe.. make sure your pulleys are the same width or youll eat belts like no other. I cant make a video cause I moved out of state.

[suchfunstuff]

If that thing goes faster than factory, you MUST let us in on your setup! What did you do with the pulleys and varidrive? The only thing I can tell is that you are still using the 1 speed rear.

[cobrafied]

theres the drive pulley and then the rear pulley, the rear pully is a 2" pulley, and i believe the front one is still stock, the 2" aftermarket pulley was hard to find so soon, so its actually the wrong size and eats up belts real quick, we went through about 5 belts trying to get the right lengths and widths... next year should be reliable.

[suchfunstuff]

And you're still using the varidrive? So you just kept trying different 5/8" belts to compensate for the differences in pulley sizes?

[sdylke]

foot peadal all the way best set up

[dangeroustoys56]

I dunno- i originally put a hand throttle on my murray- i didnt like it as much as i thought, so im still in process ( too much other stuff to do) of putting a foot throttle on it.

[cobrafied]

I guess it would be hard to operate if you had to turn your wheel so much and it was attached to the wheel. interesting, is that what you didnt like?

[dangeroustoys56]

Most my issue was i put it on the same side as my shifter- so id have to let off the throttle to shift- i had to mod the steering wheel a bit to make the throttle fit it ( er cut it) - i did notice the cable ( even tho tied down) would get tighter when i turned , but by then i had hit the wheel stops.

I used an ATV brake lever- i think that was a bit large to be using, was sorta awkward to press.

[dangeroustoys56]

Nice tractor- gotta love the twins.

I was gonna say about putting a foot or hand throttle on it- but y already mentioned y were gonna- it makes a WORLD of difference in power/reaction time.

Im tinkering with a couple tractors, just for fun- a 94 murray with a twin and a 69 wheelhorse body on a 96 MTD chassis- should be interesting.

[douellette88]

wow nice mower. i have a craftsman with a 18hp opposed twin and i want to do an exhaust like that, where'd you get the pipe and how'd you do it?

[cobrafied]

its blackpipe-plumbing pipe man! i used a torch to heat some of the pipe to bend it in certain areas (only to bend the pipes upwards out the back) other than that just screwed everything and tig welded... blew holes through the frame with the torch to put the exhaust through it for a solid fit for racin cuz we get a lil rowdy ;)

[JudgeSteelflax]

that is america, i need to make a mower with a two cyl. and duals my self.

[cobrafied]

Heavy? I dont know it works for us we arent in professional races or anything, got the mower for free, my tranny is belt drive, gonna switch to centrifugal or something for next year with thumb throttle..more mods to come but yeah.

[yamaharules163]

Nice machine, how do you like the opposed twin, is it heavy?

[cobrafied]

righton! thanks!!

[paulbreor]

lol,you have some really nice toys in that garage,but the racing lawn mower is the cherry on pie!

[cobrafied]

thanks i meant to take that part out i dont like showin off, had a few beers!

[Nickgarage]

I  love the color!

[cobrafied]

thanks! rattle can black night metallic! worked well, needs somethin else though, we didnt win show mower :(... gonna go with some sheetmetal or diamond plate on the sides and foot. hood scoop with raised intake outside of the body like a blower scoop... maybe some orange or green headlight bulbs too.