I need ideas for a live axle

[Carp]

I just picked up this kart for $68 on ebay. It has a tube welded in place that had an axle inside that wasnt live.....one wheel peel...noooooo. I need help/ideas on converting this to a live axle with some pillow blocks or bearings I guess. I can weld.... Thanks! Looking forward to anyone's ideas or even some pictures...[ATTACH][ATTACH]kart 3.jpg[/ATTACH][/ATTACH]

[ckau]

Take a look at ********. They got everything you need. axles, bearings, hangers, hubs, etc. You can get a complete bearing/ hanger kit in one package. Cut that tube off, position and weld the hangers, everything else bolts on.

[Carp]

I was thinking about cutting off that tube but it is actually the end of the frame and that rear hoop is welded to it. That axle tube is my concern.....I need to make room for a sprocket. I have a bit of planning to do.... Thanks ckau

[metalstudman1]

Find some tubing/pipe that will slip over the side rails on the rear. Cut the back off the frame and eliminate the heavy axle tube (it might be the right size to slip over the smaller frame rails!) sleeve the frame from the bends to the roll cage supports.You should probably move the engine plate towards the center or on the 2 short center frame supports to give you the clearance needed for the sprocket and brake.Now your axle bearing plates can be installed on the new sleeve and have some added support.

[Carp]

I did exactly that! except my sleeve isnt that long.....my sleeve was an old metal insert from a leaf spring bushing....itwas about 5 inches long. I welded it in. Now I plan on spliting a piece of tube to brace it along the outside. That was the engine plate side. I just cut the tube on the other side and welded a short bolt in the tube for strength. I planned on welding on bearing supports right where the pipe used to be. I'll post some pics tomorrow. Thanks metalstudman1.

[Carp]

Question....should I go with the 1" stepped axle (down to 3/4 on ends) or just a straight non stepped 1" axle? I want to go with the popular choice so it is easy to find wheels that will work.

[metalstudman1]

I have a question about your engine placement- so you're leaving the engine plate where it's at? Meaning your sprocket/chain is on the out side of the frame? Now about the type axle- what type of hub are you going with? 4 x 110mm is what's on most karts,(most smaller/mid-size atv's use this pattern on the rear wheels too) 4 x 4 is golf kart pattern and very common also.You need to consider- the axle will have to be much longer for a hub, sprocket holder and clearance out side the frame. The reason most live axle karts have the engine in the center of the frame is for the hubs to be close to the outer frame and bearings to minumize bending and equalize torque to both wheels.The way the axle is made on the 1" to a step down (where most breakage occurs)is very important (tapered is strongest vs straight cut down to 3/4". 1" straight has the weak point inside the hub and will take more abuse.

[Carp]

I plan on moving the engine plate to the center and the sprocket will be inside the frame. I'm going to run a jackshaft to make a gear reduction since this is for my 5 yr old. Not sure if I should go with the drum/band or mechanical disc/caliper. I plan on mounting that inside the frame also if possible. So far I'm up to $190 at BMI including rims wth hubs welded on with tires, 1" straight axle, drum/band, hub & sprocket and 2 locking collars. I've seen complete axles on ebay for $199 with no guess work.

[metalstudman1]

Great -post some pics. Just remember dad will be driving it too!!!(always lots of test runs) I take it your going to use a standard friction clutch with #35 chain?

[Carp]

yeah, standard friction clutch on this one with a gear reduction. #35 chain seems so weak.....I was going to go with #41 so I could run #40 or #420 chain if needed. What are your thoughts on chain selection??

[Carp]

Also, what are your thoughts on a brake system....band/drum or mechanical caliper. This thing wont be going fast for now.

[metalstudman1]

Any of the braking systems will be fine-Band is by far the easiest to install and maintain- go with the 6" size if possible. You're limited on the #35 chain as this the most common drive sprocket with a friction clutch. A jack shaft isn't just for gear reduction, it's only necessary if you can't get a big enough axle sprocket (more than 50teeth) to clear the ground with the smaller tires. If you were to put tires larger than 16"/18" the #35 chain wouldn't be strong enough. Horizontal engines allow for throttle limiting screw at the pedal or cable end without causing longterm damage to the motor not running max rpm's

[Carp]

I was thinking a 10 tooth clutch My other daughters cart is 9 / 54.....600 with a tav-30. The tav is a 3:1 reduction in low gear.....600 x 3.....1800.....with 20" tires. This cart will have tires around 16".......so even with a 10/72 thats only a 720 ratio....

[Carp]

I want at least a 1200 ratio or deeper......

Thats going to require at least a 2:1 reduction

[Carp]

posting pics now....

[Carp]

done 1.jpg

done 2.jpg

done 3.jpg

[Carp]

I ordered a complete axle set-up, clutch & jackshaft from BMI. For the price, I could have just bought a used kart and scabbed the parts!

[metalstudman1]

That's true -but it's the experience you'd have missed.Nothing like turning a POS kart into a FUN machine.

[Carp]

Originally Posted by metalstudman1

That's true -but it's the experience you'd have missed.Nothing like turning a POS kart into a FUN machine.

I agree completely....I really do enjoying the welding.....arc/stick welding that is!

[Carp]

Ok....so here are the updated pics with the engine, clutch, jackshaft & axle. This thing has the torque of a backhoe!.......In the 3rd pic, I had to create a pocket in the bar so the recoil cage would clear during chain adjustments. kart1.jpg

kart2.jpg

kart3.jpg

kart4.jpg

[metalstudman1]

Looking good!!! You sure have a lot of axle hanging out there. Unless you bought a HIGH dollar axle that allows flexing you might bend that one pretty easily.Well does it have any top end to go with the backhoe torque?

[Carp]

No top end at all....I geared it for my 5 yr old daughter until she gets the hang on driving. That axle is kinda long...... That back of the kart was only 18" wide but I wanted the rear tires out there for stability. Not sure what to do about that. I could shorten it, rethread it and find some wider rims to keep the tires out there???

[metalstudman1]

Just keep a watch out for snagging trees in the turns and don't jump it unevenly.The kart looks great,you're doing an excellent job- I'm sure your daughter will love it.

[Snoopy]

Nice looking work, and the kids will never forget the lessons of making it work!
Snoopy

[Carp]

Thanks Snoopy. I've since put larger tires on the rear and put the 145/70 tires up front. I think I went the wrong route with the clutch and jackshaft.....the torque converters slip way less on hilly terrain. Oh well......another lesson learned.

[Carp]

It's geared really deep 18:1 but that little drum clutch just cant hang when pulling out on a hill.