Fat Tire minibike the build

[karl]

I have a mock up of it, I got the top of the frame done, 18in tires, 3hp briggs. Sorry for crappy photos my camera is charging, will keep posting updates.

 

[gokart14]

cool

 

[karl]

I got more done, then the welder ran outta wire. For the rear axle I got a good idea, I got a blown up transaxle and I am gonna use the shafts for the axles. I will post more updates when I get more wire.

 

[Bluethunder3320]

wow man. check out the build i was doing until i ran out of cash. i still have the frame but i need tires and an engine but i might use the H60 tecumseh i got to rebuild.

its just like yours. just to give you an idea.

http://www.diygokarts.com/vb/showthread.php?t=10237

 

[Doc Sprocket]

In your other thread, you mentioned the use of 3/4" EMT. Make sure you've got TONS of ventilation while you're welding it. The fumes will seriously screw you up. Put a fan close by, blowing the fumes away from you...

 

[karl]

I got ventilation covered, I welded by a doorway with a box fan blowing out the door.

 

[Doc Sprocket]

Good. Better safe than deceased. Are you going to use the turfs, or the knobbies? I ask because I get lousy traction with the turfs, and am probably going to change to knobbies hoping it'll help.

I assume you'll be in dirt, gravel, mud and grass like I am.

 

[karl]

I dont know, I think the turf savers will be ok, There is alot more weight focused on the tire on a mini bike. Besides, the knobbies are almost bald and they fit on a 1in solid axle that I have. Wait I got some 18in tire chains

 

[Doc Sprocket]

Well, I hope you have better luck with the turfs than I do...

 

[anderkart]

Well, I hope you have better luck with the turfs than I do...

I agree knobies would be better but how much psi are you running?

You probably already know all this but you might find just 5 to 10lbs still holds a bead and hooks up a lot better.

 

[Bluethunder3320]

i have 18x8 turf saver rear wheels on my kart and it does fine when i go crazy off road.

only peels out when i take a sharp turn and the weight lifts off one side and since i have a differential that wheel spins super fast.

 

[Doc Sprocket]

I agree knobies would be better but how much psi are you running?

You probably already know all this but you might find just 5 to 10lbs still holds a bead and hooks up a lot better.

I run my pressure so low that every now and then I'll hook a hard corner, the bead will burp, and presto- I've got a flat. If I don't switch to knobbies, I will be installing tubes.

Don't get me wrong, the turfs are actually very good on some surfaces like hard pack dirt and even asphalt. But more often than not, I'm in loose stuff- gravel, dirt, mud, snow, etc.

 

[karl]

I got 18in tire chains with cleats that will fit those tires. Traction solved

 

[Doc Sprocket]

It certainly would! I'd just hate to think what happens when a tire chain lets loose at 45MPH!!!

 

[anderkart]

I run my pressure so low that every now and then I'll hook a hard corner, the bead will burp, and presto- I've got a flat. If I don't switch to knobbies, I will be installing tubes.

Don't get me wrong, the turfs are actually very good on some surfaces like hard pack dirt and even asphalt. But more often than not, I'm in loose stuff- gravel, dirt, mud, snow, etc.

Yeah I agree and figured you'd already tried the lower pressure thang. You could always do the DIY bead-lock mod with a few sheet metal screws coated with silicone...

 

[karl]

UPDATE I traded my buddy some stuff and got a 6hp tecumseh power sport with a comet tourqe converter assembly. That will replace the little 3hp. I will pick it up monday. I got a little more work done on the frame, mostly welding because I tacked the frame together at first. I got a pic of my welder, it is a lincon pro core 100. Will keep posting updates. Getting closer to

 

[migel101]

that will be a little upgrade in speed

 

[karl]

I started a poll, should I gear it for speed or power? I got a 6hp tecumseh with a comet tourque converter now soooooooo

 

[sideways]

I say gear it for about 20mph. Should go pretty good with that engine and torque converter.

Gearing is pretty easy to change later anyway.

 

[Bluethunder3320]

i would say 25-30. thats plenty of speed on a home made bike, and the torque will still be there for towing and hill climbs.

also, realize that turf saver lawn mower wheels will be off balance and wobble at high speed.

my kart has speed wobbles. it should have been going 40mph, says the calc, but ill check.