go-kart w/ lawnmower engine, help!
- Thread starter Clip
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Clip said:
If you arrange idler pulleys correctly, then tq is great. My 11hp single cyl briggs will pick the front end up from a stop. The first one i made a had a wheelie bar......gee wonder why. The 18hp one would ride the bar like mad with the 2.5 pulley. Til one day is broke and i flipped it, hit a tree at like 20mph and messed the front up. I ended ed up accidentally killing it playing chicken with another race mower. At last second guy turned toward me by mistake.:cry: We hit so hard...that it broke the block on 18hp!(opposable cyl like a boxster motor) Wheel meet block = cracked block......needless to say...didnt do that again.
I had thought about a go-kart with a tractor rear end. The motor would sit behind the axle making it like a porsche kinda. Im alway coming up with crazy new ideas n stuff. Ill find my sketches maybe.
those look fairly simple. lol. but maybe there's more to it than meets the eye eh? 
i'm watching this thread, i have a 11hp briggs outside i've always wanted to turn into a gokart, and i have another one with a 5speed tranny and a blown engine, combine the two with a smaller pulley....there you go...apparently.
so an 11hp engine and a stock lawnmower transmission is enough huh? is that for sure? i didnt think it would work so i dropped the idea...figured the lack of torque would suck but maybe it wont be lacking....
i'm shooting for something that will hit approx 40 mph....i dont need anything more. what are good clutching methods? stock idler pulley setup?
i'm watching this thread, i have a 11hp briggs outside i've always wanted to turn into a gokart, and i have another one with a 5speed tranny and a blown engine, combine the two with a smaller pulley....there you go...apparently.
so an 11hp engine and a stock lawnmower transmission is enough huh? is that for sure? i didnt think it would work so i dropped the idea...figured the lack of torque would suck but maybe it wont be lacking....
i'm shooting for something that will hit approx 40 mph....i dont need anything more. what are good clutching methods? stock idler pulley setup?
my goals are the same, around 40 with plenty of turf-tire smoke.
simple setup, with pedals and steering coming from northern. belt will be an advance auto item as well as gas and electrical. battery is going up front, gas tank under my seat (seat coming from the junkyard), and engine/trans sitting above the axle. im not sure how to rig it yet since the transaxle is meant to hang under the frame with the old brackets. im sure i can find my way around that with an arc welder, grinder and hammer.
most karts have 4-8hp engines, mine's at 14. h8r has said that the 5spds dont hold up as well as older 3 spds but its all ive got to work with since its vert output.
as for the idler pulleys, i have no clue how they even work or what they do, so ill cross that bridge when i come to it.
good clutching methods...couldnt tell you. when i took my transaxle apart it looks like all the clutch/brake pedal did was press the brake pads and bring the trans to a stop so i could shove it into another gear. its either so old or so smooth that i just shift without using the clutch/brake. just yank the handle around. does the clutch take the power off of the belt by adjusting a pulley or something, because at first glance it looked like it just pressed a rod that pushed pads into the 1" brake disc.
simple setup, with pedals and steering coming from northern. belt will be an advance auto item as well as gas and electrical. battery is going up front, gas tank under my seat (seat coming from the junkyard), and engine/trans sitting above the axle. im not sure how to rig it yet since the transaxle is meant to hang under the frame with the old brackets. im sure i can find my way around that with an arc welder, grinder and hammer.
most karts have 4-8hp engines, mine's at 14. h8r has said that the 5spds dont hold up as well as older 3 spds but its all ive got to work with since its vert output.
as for the idler pulleys, i have no clue how they even work or what they do, so ill cross that bridge when i come to it.
good clutching methods...couldnt tell you. when i took my transaxle apart it looks like all the clutch/brake pedal did was press the brake pads and bring the trans to a stop so i could shove it into another gear. its either so old or so smooth that i just shift without using the clutch/brake. just yank the handle around. does the clutch take the power off of the belt by adjusting a pulley or something, because at first glance it looked like it just pressed a rod that pushed pads into the 1" brake disc.
When you want to go over 20 mph you have to look for a different transmission. Most 5 speed transmissions use a non ball bearing design and wear out very quickly or just die quick. I use an older transmisission that is ball bearing and is a three speed. Also, You have to do something to lower the center of gravity......or you will find out going round courners can be scary:biglaugh:. (flipping) I cut and redid my frame to lower and make my tractor a hardtail lowrider. Also, i am lookin into making one of my karts from the plans showed earlier.
all or most of these older mowers use a belt drive system that is hinged. there are a set of pulleys that apply pressure to the belt, allowing it to grip the rear tranny input shaft pulley. when you push the break pedal, it moves the pulley setup, on a hinge, to loosen the drive belt just enough so its floating, and does not grip. push the pedal harder and the silly little disk brake is applied. carefully take a look underneath while you depress the pedal. (hint- this wont do jack unless the pre-load spring is there to return the pulley to the gripping position, just incase yours fell off and you didnt know it.)
i have a 3 speed and a 5 speed transmission.
3 speed has a broken/screwy reverse gear, i'll have to look into rebuilding it because i took it apart to investigate it not working at ALL...couldnt figure it out, and put it back together. now i've got three forward speeds. decent, but i want reverse if i'm going through the trouble to mount this thing.
as far as clutches, this is the main problem, along with getting power to the rear end if you plan on any sort of suspension setup. belts just make everything screwy. i have found a design for this application that i really like, i'll look for the site later. the guy never finished but it was pretty sweet. full suspension, dual drive trailing arm in the rear. possibly a 4wd CVD up front i dont remember.
i'd like to look more into the durability issue in these tranmissions, because the 5 speed would allow some brute torque and a slightly faster speed....
are you guys thinking about going CVD in the rear? the stock track is quite narrow...
i'm thinking a normal width gokart...just homemade and not bought. i cannot nor will i pay hundreds of dollars for something like this. i figure 50 bux into rebuilding the motor/adding a nicer muffler, and then supplies for the frame, which i'd fab myself. (thats going to be very hard...but its a great way to learn!)
i have a 3 speed and a 5 speed transmission.
3 speed has a broken/screwy reverse gear, i'll have to look into rebuilding it because i took it apart to investigate it not working at ALL...couldnt figure it out, and put it back together. now i've got three forward speeds. decent, but i want reverse if i'm going through the trouble to mount this thing.
as far as clutches, this is the main problem, along with getting power to the rear end if you plan on any sort of suspension setup. belts just make everything screwy. i have found a design for this application that i really like, i'll look for the site later. the guy never finished but it was pretty sweet. full suspension, dual drive trailing arm in the rear. possibly a 4wd CVD up front i dont remember.
i'd like to look more into the durability issue in these tranmissions, because the 5 speed would allow some brute torque and a slightly faster speed....
are you guys thinking about going CVD in the rear? the stock track is quite narrow...
i'm thinking a normal width gokart...just homemade and not bought. i cannot nor will i pay hundreds of dollars for something like this. i figure 50 bux into rebuilding the motor/adding a nicer muffler, and then supplies for the frame, which i'd fab myself. (thats going to be very hard...but its a great way to learn!)
You know the idea of a swing arm suspention? Like the older atv or qaud rear end? Thats what im doing first. The axles will have extentions and the motor and trans will be mounted as one unit. The transaxle will be mounted to swing arm and axles will have own bearings to ride on.(one big swing arm) Im going to be using a heavy duty chain and centrifical clutch.(more durable) Btw, the "cheaper" go-karts use the swing arm design.
yeah that system is kinda what i meant by trailing arm suspension. this one i saw was weird though, it had two seperate swing arms for the rears and a seperate chain for each, mounting the differential and sprokets off the transmission inboard. perfect idea but he never finished the kart as far as i know.
i dont really want the engine to be bashed around being right above the rear axle... i'd rather have it mounted on the main frame... its just getting that power to the rear. maybe i could take your idea and implement some small CV shafts from a small car like a geo metro... then i could mount a clutch between the engine and tranny, and then it could be on the main frame, and then out to the independant suspension.
the only problem is getting the angles correct so it will not bind. maybe i could also glean the suspension from a geo. should be small/light enough.
i'd look for a VW rearend but i dont want something so massive, i want a kart not a big buggy that will hit 90. maybe i could but the a-arms off a VW....
i dont really want the engine to be bashed around being right above the rear axle... i'd rather have it mounted on the main frame... its just getting that power to the rear. maybe i could take your idea and implement some small CV shafts from a small car like a geo metro... then i could mount a clutch between the engine and tranny, and then it could be on the main frame, and then out to the independant suspension.
the only problem is getting the angles correct so it will not bind. maybe i could also glean the suspension from a geo. should be small/light enough.
i'd look for a VW rearend but i dont want something so massive, i want a kart not a big buggy that will hit 90. maybe i could but the a-arms off a VW....
is it more feasible to use a motorcycle engine, clutch, and tranny?
i think i want to find an old setup like that, rebuild it, and go from there....
what do you think? i figure 20 hp or something from a moto engine and i'm set...
i think i want to find an old setup like that, rebuild it, and go from there....
what do you think? i figure 20 hp or something from a moto engine and i'm set...
LOL.
i'm really hoping to get a moto engine with a tranny as well...then i'd have pleanty of gears to rip through!! and i wont finish until near the end of summer probably... i have to make plans yet. but i have some in my head!
i'm really hoping to get a moto engine with a tranny as well...then i'd have pleanty of gears to rip through!! and i wont finish until near the end of summer probably... i have to make plans yet. but i have some in my head!
OK well temptation hit me and i decided to throw together a quick out-of-scale mock up of what's in my head. i spent only a few minutes on it so please excuse the ill-done proportions. (mainly the teeny wheels...)
what do you think? that is my rough idea for a horizontal shafted engine.
i'll draw up plans for a vertical shafted one in a minute...
what do you think? that is my rough idea for a horizontal shafted engine.
i'll draw up plans for a vertical shafted one in a minute...
try & be like this =D
http://www.automotosport.info/?prikaz=vijest&id=236
original website - http://www.kartvader.com/
http://www.automotosport.info/?prikaz=vijest&id=236
original website - http://www.kartvader.com/