Need help please!!!!

[tgras141]

Hey guys, i am totally new to this whole thing, im starting with a simple little probably edger engine go cart. i know basically what is on this site about go carts, my main uses for this cart would be mostly asphalt use and some hard packed dirt use when we go riding in the desert... um so basically im starting from scratch, i do have the ability to do basic welding, i have a live axel to use, some tires, and an edger engine, im also thinking of using a little 70cc engine from a small dirtbike such as a xr70. If you have any suggestions or anything that has worked for you in the past, please please PLEASE!!! let me know. thanks soo much, ill have pictures up soon and i will also let you know how many teeth are on the sprocket. and if you just happen to live near long beach, california and would have some old crap parts that you would be willing to donate i would be oh so grateful!!!!


let me know and thanks again

 

[anderkart]

If you ever got that tiny edger engine all mounted up and working you'd most likely be very unhappy with its performance. A Honda XR-75/80 motor with its transmission would give you much-much better performance. Those are cool little motors, I used to ride an old XR-75 and it pushed my 235lb weight around surprisingly well.

 

[tgras141]

haha ya, im 15 and about 140 but i have a out of service xr 100 in the garage after i moved on up to a yz250f. but i would rather not disect that little piece of equiptment, my thing is i dont want to have to work the clutch, cuz its gonna be hard enough to set it up for shifting, thats why im thinkin somethin smaller??? whattya think??? and do you know anywhere that i could get a little old engine?
ps do you know any way i could hook up the lever used to shift to where i can shift it maybe by hand or even by foot??

 

[anderkart]

Lots of guys have made a hand shifter setup (like a car stick shift) that simply ratchets back and forth with a linkage rod attaching to the stock bike shift lever. (thats been repositioned upright or downward) Then they just mount the stock clutch lever to the shifter itself for easy one hand operation. You could probably devise a simalar shifter setup that was foot operated and then mount the stock clutch lever somewhere.

The harbor Freight 6.5hp engines seem to be a popular choice. Here's link to a coupon: http://www.oldminibikes.com/forum/g...p-clones-sale-again-get-your-coupon-here.html

I've seen quite a few small engine bargains for sale on my local craiglist, you could start watching yours for a deal. Instead of looking at all the ads, Id suggest you use they're search function using each of these search terms: Briggs, go kart, gokart, go cart, gocart and Honda engine. I've also seen quite a few complete running (or near running) karts selling for under $100 on my craigslist lately...

 

[Russ2251]

What size is edger engine?

 

[tgras141]

the biggest thing ive found is a 3.5 hp in my grandpa's backyard, its out of service
but im lookin right now... but do you know much about welding ander??

 

[modelengineer]

The shifter is easy as pie to set up, dont let that stop you. The XR75 is a much better choice of motors.

 

[anderkart]

the biggest thing ive found is a 3.5 hp in my grandpa's backyard, its out of service
but im lookin right now... but do you know much about welding ander??

That 3.5 wouldn't be super fast, but not as bad as I was saying. I misread your 1st post and thought you'd meant a tiny weed eater engine. If you can get that 3.5 goin and you dont want to tear you dirt bike down, go for it man.

I'm a crappy welder...

 

[tgras141]

i did the speed calculation thing and i have 10 inch tires, with a 40 tooth axel with a 14tooth sprocket (i believe, i may end up using a different one) and it runs at 3600 rpms but it said the thing would go like 40, now that seems unlogical to me... what do ya think? cuz that would be perfect for me

 

[brendonv]

I dont think u would be unhappy with the 3.5hp although because the 70cc is a bike engine and has gears its a much better choice. It would have greater acceleration and would be more of a thrill to ride changing gears all the time. I have a 3hp on my kart and it hoots pretty good. Acceleration is pretty good. Im currently rebuilding a 160cc 2 stroke victa to put on there. Just ordered a gasket set for it, should be here 2morrow arvo the guy said so should have it on the kart by monday ish.

 

[anderkart]

i did the speed calculation thing and i have 10 inch tires, with a 40 tooth axel with a 14tooth sprocket (i believe, i may end up using a different one) and it runs at 3600 rpms but it said the thing would go like 40, now that seems unlogical to me... what do ya think? cuz that would be perfect for me

Yep, looks like that combonation should be good for 37mph on paper anyway... Sometimes lower powered engines (especially with heavier kart loads) wont spin up to their full 3600-rpm potental while climbing or even driving on flat ground.

Many small engines develop they're maximum torque at some point below 3600-rpm's (like meyby at 2500) and while they have the ability to turn higher than 2500 rpm's, many times they're actualy producing less overal power while doing so.

So what I'm trying to say is, going down hill your gearing combonation should go 37-mph at 3600, (even with a 1hp engine) but you'll just have to try it and see what your top speed really turns out to be with your engine and driving conditions.

With a 3.5 hp engine, and unless you've got huge open areas to always be riding around at top speed, you might find you'd have more fun with the better acceleration of something like a 14/60 gearing combonation.

 

[tgras141]

one last thing for now, ummmm... have you found any helpful posts in the past on how to set up the pedal for throttle and pedal for brake, i think for the brake im gonna go with the band style kinda thing, its cheap and fairly easy set up, ive been looking at sites with free plans, but theyre all jumbled, i need something with steps, not just a diagram, cuz thats just kinda overwhelming.

and if you are a bad welder... did you have someone do it for you?? or did you just prebuy the frame and everything, i could do that but on limited funds, it just seems like a waste to have it done if i have the resources to do so.

 

[anderkart]

I cant think of any specific pedal threads, but that'd make a really cool new thread for you to start. I'd ask everyone to post some close-ups of their pedals, linkage and rear connections. Sometimes just seeing how other karts have been done is better than any step by step guide.

Here's my throttle pedal, It's just got a simple cable going to the carb.
My brake pedal is the same only with a 18" linkage rod going to the master cylinder:
(If you start a pedal thread I'll take/post closeups of everything on mine)

I've seen quite a few home made pedal setups just by looking at the pics on our Photo Gallery & Project Log here. The simplest one I remember was just an old gate hinge and a spring.

You'll find a few pedals for sale here:
http://www.google.com/products?hl=e...a=X&oi=product_result_group&ct=title&resnum=4
(many only need a 5/16" hole drilled in your frame or meyby a 2" section of 5/16"ID metal tubing welded on top to mount, you could build and mount your own pedals pretty easy)


I just bought a used factory made kart. I've only messed around a little welding stuff cause I've usually had friends around that do a much better job.

 

[modelengineer]

it runs at 3600 rpms but it said the thing would go like 40

The engine won't have enough power to spin up to full revs, as someone has previously said. My 3.5hp 2-stroke kart with 8:1 reduction would do about 25mph with pretty piss-poor acceleration. If a gokart can't out-accelerate a Toyota Echo, then it's not got good acceleration LOL.

*EDIT* pic of pedals. Note the right pedal is throttle, left pedal is clutch (yes, a 1 speed kart needs a manual clutch lol!)

and the clutch just for giggles

 

[tgras141]

im starting the thread, its called "Pedal Pics", what kind of brakes have you found best for a small kart??

 

[modelengineer]

Hydraulic disc brakes. Hands down. Can also be very cheap from ebay.