mini buggy videos- ATGC update

[ryf]

videos of my lawn mower engine and tranaxle go cart/minibuggy at work and play. currently its restricted to about 3/4 throttle, but it still goes pretty quick. thanks for looking

http://www.youtube.com/v/skN9XjUF0PI

http://www.youtube.com/v/MXkKVqHyVZI

 

[wingnut]

Very nice. It looked like you where able to shift gears on the fly. I didn't think you could do that with a lawn mower transaxle. Every mower I've ever owned would grind the gears if I tried to shift without coming to a complete stop. Is that a feature particular to the pearless transaxle you're using?

 

[ryf]

peerless 820 (found in the big boy mower/tractors for plowing and etc)

ummm.. you can shift em all on the fly if you use the clutch like a car and are using a gas pedal, problem with them on mowers has always been the motor speed doesn't change when you try to shift, thus making it much harder to get the gears to mesh....

I drive a tractor trailer for a living and not using a clutch is called slip shifting, very similar technique except I use I use the clutch to take the load of the tranny between gears (not double clutching like they teach in rigs, just like in a car with syncros) the key is figuring out the rpm for the speed and do it with "firm quickness" so you don't miss your points, and yeah I still mess up sometimes, usually downshifting/slowing down

 

[wingnut]

ok. So it sounds like the mower trany isn't designed for shifting on the fly but you've developed the skill to do it anyway. Does hat sum it up? I was entertaining using a mower trany on a utility cart for the wife to get around the farm with but I get the impression that shifting will not be something she will want to do regularly.

 

[ryf]

what kind of speeds are you planning? if you doubled the input (use a pulley 1/2 the diameter on the transaxle side) and open your governor to 3600 you could do almost 20mph on stock tire size assume your current top speed is around the average of 6mph. that would not really require shifting except when pointed uphill. I would say most people could run it without shifting at about 15mph top speed almost all the time (95%) assuming thats what you geared it for with an empty vehicle. loaded you'd really need to slow down to protect the axle from weight loads or do what I did, run it by chain to another axle. the second axle takes the blows, leaving the transmission to only deal with moving loads. I used a cheaper 205 peerless, it would have worked well except for towing, and it would not deal with higher speeds than about 15-20 mph without stay with stock tires. my tires are 24" and my load is greater than expected, so it didn't fair well... but it did work great until I tried to pull a well stuck atv from a river. got the ATV out but thrashed the main ring gear.. pretty tough considering. the 820 gears are machined, the 205 gears were cast.

 

[wingnut]

I'm looking for lower speeds. 15mph would be plenty. I was however hoping to make it a two seater and have enough left over to haul some hay. Sounds like that might work with a Peerless 820 but anything else will limit me to a single seater. I'll go with an 820 if I haven't seen one on the used market yet. I've seen some rebuilt ones on fleebay for $190+ shipping but the whole point was to keep the cost down by allowing me to use an old vertical shaft motor from a used mower. If I'm going to spend $200+ on a transaxle, I might as well spring for a horizontal shaft motor and just use a clutch. Thanks for the help.

 

[ryf]

I got mine from a mower junkyard, $75 bucks for the 820, I'd try what you have, if you aren't pulling anything heavier than what you'd pull with a mower, it will be fine at slow speeds. plus you can always stay in lower gears like 1-3rd and it will still go slow and be fine. my first gear is around 3rd for that reason, too slow to drive but great for climbing and pulling. also consider using a centrifugal clutch instead of a foot clutch, much easier for a novice to not break stuff. just a thought. the issues I had were from my massive over driving of the parts with a bigger than recommended engine

that said, I built my cart with enough frame for a snowmobile setup... so leave room for growth.

 

[Jblankster]

looks nice! cant wait to see the snow mobile engine in there lol

 

[ryf]

not till it breaks, thanks though


http://www.youtube.com/v/84Wv37eB638

recut for youtube with soundtrack, I was bored this morning

 

[oscaryu1]

Looks very nice! All custom?

 

[ryf]

yes, there are builld threads on here

 

[gregles]

i saw that a while a go on there ... dose it have rear suspention? or what?

 

[tykenfitz]

i thinking of using a transaxle like that for a shifter kart but would it be a bad idea be cause it's hard to shift? if you had a power full engine and the kart was pretty light what sppedds might you expect would another type of manual trans. be better?

 

[ed1380]

we have 20 year old wizard riding mower. i can shift on the fly. just press the clutch in a bit and do it

 

[tykenfitz]

Also, it wouldn't do any off-roading because I live in the city I just need a pretty fast street kart could a setup like this be good for 2-seater?

 

[ed1380]

if you gear the output of the mower transaxle then yes. over 12mph the bushings in the tranny die

so about 12teath on the tranny and 36 on the axle/wheel

 

[tykenfitz]

So, what your saying is don't just put a smaller belt on the tranny input, put a sprocket on the tranny output?
Wouldn't it be hard to turn then because the wheels would be spinning at the speed?
EDIT: How about some big a$$ rear tires so the tranny wouldn't have to spin that fast but you would still get alot of distance from not that many rpm?

 

[modelengineer]

Tranny input going faster = faster wearing out bushes
Tranny output geared faster = faster wearing out gears, or bending something internally from increased stresses.

Remember these things aren't designed to do more than 10mph max. If you could replace the bushes with bearings then it might be really good, I don't know

 

[ed1380]

you could try to find a used or broken 2stroke engine w/ tranny

even if you gear it down a bit, youll still top out about 40

 

[ryf]

sorry, been busy lately, the output is gear up, as is the input on mine, and its currently topping out at 52 MPH since I re-geared it recently. I have added rear suspension, we are still working it out to see if it works, so its off the record, lol. the 820 trans is all steel cut gears, not pot metal or sintered like the cheaper ones, the big failure point on the cheaper ones is the main axle ring gear, and the 820's ring gear is 3-4 times as big, and better quality. yes the bushings will wear out, but they can be ordered from any tecumseh/peerless dealer. you definitely need to over engineer the mounts for any transaxle your using, as the biggest failure point on racing mowers is twisting off the axle housing ends, because the heavy front of the trans isn't properly supported when you are bouncing along offroad.

I used my transaxle as a transmission only, this will GREATLY increase its life as the axles are under a static load, which helps the gears and housing not get flexed which helps start the damage process. if you were running a cheap transaxle with a 8-12 hp engine and centrifugal clutch on a light weight street cart, it would hold up well, I used a cheap tranny, but the weight of me (350lbs) and the buggy (another 500+) was too much for it.