murray explorer project.

[Dougthewelder]

my kart started life much like the one in this picture.

By vitamaxx at 2009-09-27

my spoiled step brother wrecked it into a tree and decided he didn't want it anymore. at the time i was learning to weld. the front of the cart was broken quite badly, the front axle had been riped from the frame when it was wrecked. so as one of my first projects i designed a front suspension for it modeled after a 4x4 pickup.

this is a pic of my friend riding it. i was in a photography class when i took this so i used a B&W film camera.



so as you can see it looked quite silly with a front suspension and the same crappy 1 wheel drive rear setup. i had always intended to design a rear live axle set up but i got distracted by school. after i got my degree in welding and blacksmithing from a community collage i decided to get a studio art degree.

but now that i'm done with school i finally get to build a shop to go back to doing what i enjoy most. welding and fabrication. i do art stuff as well as fun things like go karts.

so having some free time and the tools and a place to do it i ordered a 1" axle and bearings as well as a 6hp LCT engine and a TAV30. i found some turf saver tires already on the rims for a good price at my local tractor supply Co. i originally meant to just bolt the new setup to the frame with no rear suspension but when i got the axle in i started feeling that i would not ultimately be happy with that. i began thinking what sort of suspension would be good on my cart.

my #1 goal with the suspension was to relieve torsional stress from the frame. this is because the frame on this thing is so-so in strength at best. most of the go karts i had seen had a rear suspension where the whole section with the rear wheels and engine where on a swing arm that could move up and down only. i felt that this sort of thing would be good for keeping the kart level but bad for keeping the wheels on the ground in uneven terrain. what i really wanted was a rear suspension that would have independent movement for ea tire and yet still used a solid rear axle. once again i wanted something like a 4x4 pick up but because i didn't had a differential and didn't want an axle the engine and TAV would need to move with the rear axle.

here are some pics of my progress.

By vitamaxx at 2009-09-27

By vitamaxx at 2009-09-27

By vitamaxx at 2009-09-27

By Vitamaxx at 2009-09-27

By vitamaxx at 2009-09-27

sorry about the quality of the pics. most are with my crappy phone camera... i will post better pics of my progress and a video soon! thanks for looking!

 

[EagleTalons]

Looking good! Sometimes if you take videos with those phones it will seem to be a better quality.

 

[rgvkid]

Wait a minute! The Rear is going to collapse under load. You need to make it a 3 link by adding 2 trailing arms. Maybe like this. I have been thinking of doing the same thing witha 3 link but i would have to mount the engine on the upper triangle link and the trailing arms on the bottom. Goggle "Prerunner 3 link" and imagine the same setup as you have with the triangle ontop and the engine mounted on it.

 

[Dougthewelder]

i have a cross link you can see it in the picture. its the curved one. i made it an arch so it would clear the sprocket and brake disk. it definitely works i have gone for a ride around the yard once already with no brakes (so i couldn't go to fast). i just finished the brake system tonight and will post pictures of it soon in this topic.

 

[Dougthewelder]

home made brakes!

so i needed brakes for my cart. the original band brake was never that good and now the kart weighs even more and is more powerful. there were a few online options but i thought it would be fun to try to build them my self.

this may not be the best way to do this. the only thing i will say is that it is "a way" to do this. this system stops my kart, in fact i think i over designed these a bit i think they would stop a small tank! lol

ok so i started with a set of 18$ pads form the auto parts store

By vitamaxx at 2009-09-30

i just asked them for the smallest pads that had. i took one pad a cut it in half (when cutting or heating brake pads use a respirator the fumes can be bad for you). and welded square tubing onto the backs of ea half.

By vitamaxx at 2009-09-30

then i made my calipers out of more square tubing (i have a bunch of this stuff so i use it for everything lol)

By vitamaxx at 2009-09-30

By Vitamaxx at 2009-09-30

then i welded my brake pads onto longish pieces of tubing and bolted it together to look like this.

By vitamaxx at 2009-09-30

By vitamaxx at 2009-09-30

By vitamaxx at 2009-09-30

then i drilled holes in the ends of the long pieces connected to the brake pads so i could use a brake cable to squeeze them together and installed them on my cart. (i had also made a disk earlyer that day but ill spare you the "how to cut a round piece of metal demo" )

By vitamaxx at 2009-09-30

By Vitamaxx at 2009-09-30

By vitamaxx at 2009-09-30

hope this helps someone! videos coming soon (i ordered a video camera so any time now!)

 

[Dougthewelder]

well i got my video camera! so here is the first little clip i took i will upload more of me riding it and stuff shortly!

http://www.youtube.com/watch?v=q7n-OvNjedg

oh and the reason the wheels stop suddenly is i'm pressing the brakes.

 

[rgvkid]

Cool! Can't wait to see the suspension articulate. Looks good. How did you link up the brakes up front?

 

[r_chez_08]

great brake design!

 

[anderkart]

Man, you even made your own rotor. Nice job Doug, you got some hard core DIY'n goin on there.

 

[Dougthewelder]

Cool! Can't wait to see the suspension articulate. Looks good. How did you link up the brakes up front?

well i was going to use just a normal bike brake cable but it seemed a bit flimsy so i used a parking brake cable i got at the local auto parts store for 16$. its heavy duty and works great!

 

[Dougthewelder]

here is a video

http://blip.tv/file/2675516

i used blip because you tube deleted my sound...

 

[rgvkid]

Bro, you guys are cooler Cats then i thought! No offense, but at first because the kart looked kind of shotty. Maybe because of the peeling paint and scrap parts. But you guys actually look cool and the kart looks great! Kind of a Hot Rod Bobber style in my eyes. Its a bobber kart! The front suspension reminds of the old Model A car setup. I think its the Model A. Simple but effective. How did it feel? maybe you can put some towers on and use some small mountain bike shocks or some other small hydraulic shock to control the rebound. But then it might loses the fun factor.

Good idea on the parking brake cable. Can you show a pic of the undercarriage so we can get an idea on how you engineered the mechanics of the your brake system design? It seems to be working fine and im sure those pads will probably last you forever.

Great Job! Oh Yah, I want the first song on the video. Great clip also. Lets see some more, looks like alot of fun over where you live.

 

[Dougthewelder]

haha thanks for the kind words man! the ride is good i think. some shocks couldn't hurt but it seems just fine to me. i like the look of this kart also, it's got kinda a "Mad Max" thing going on i think.

the song is by a band named "Royksopp", the song name is "happy up here"

i will get more video and pics of the underside of the kart and the brake system for ya soon!

 

[rgvkid]

Cool i have some royskopp on my you tube playlist. Check out Deadmouse, he throws some dope beats.

 

[mckutzy]

wow this looks great,
so how far from the pivot point to the center of the pad?, and how long is the brake arm from the pivot to the end of where it retains the cable?
i am building a mini choper and almost done but im down to the brake issue and cant find one localy but have considered making one like yours. very nice idea.

 

[Dougthewelder]

to avoid having long arms for leverage on your chopper try something like this instead. for the bolt use something with a coarse thread or even something like the bolt out of a C clamp. you will need it to move the pads a fair amount with just one half turn. but the pressure will be outstanding. it will be like a screw press. weld the lever to the bolt head. you will need a spring return on the lever also.

By vitamaxx at 2009-10-04

a bolt like this would be good. also the length of the lever will modify your leverage and how far you have to pull the cable.

By vitamaxx at 2009-10-04

 

[Dougthewelder]

some videos! (we all love videos)

here are some videos giving a better look at the suspension and brake systems of the kart. enjoy!


http://www.youtube.com/watch?v=ei5E5E_yX0A

http://www.youtube.com/watch?v=XoDjsIdD5hc

http://www.youtube.com/watch?v=dDkzJ1nbRTI

http://www.youtube.com/watch?v=WXmriwh36qU

 

[BAMBY]

your suspension is really impressive. i like the ball joint under the mainframe...

goood break ideas too! i also had thought of the screw type, but the one you implemented on your kart... i like that a lot!

nice work,
BAMBY

 

[mckutzy]

excellent work, cart looks great,
i had originally thought of using car pads and some type of levers for a brake, but what u suggested sounds pretty good. thanks for the tip.

 

[Dougthewelder]

well what i suggested still used car pads just a different way of pulling them together. on a mini bike you don't want to have real long levers because there just isn't enough room for it.