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  #21  
Old 08-30-2015, 12:22 AM
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Quote:
Originally Posted by crazykart View Post
10 tooth on the driven and 72 or 80 on the axle sounds great for offroad.

There will be no other jackshaft between the driven and the axle sprocket unless you want to do "compound gearing", but that's a different boat that I don't think you need to sail.
Why would one need a compound gearing. What the advantages
on the compound gearing that I would not get from going direct from the series 40 10t on the driven to a 80 sprocket?

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  #22  
Old 08-30-2015, 02:27 AM
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Compound gearing allows you to get the same gear ratio as a 10t>80t (8:1) without having to use a huge 80 tooth sprocket on the rear axle.

Say if I had some 10" tall tires, but needed an 8 to 1 ratio (10>80) I wouldn't be able to get that ratio because the axle sprocket would be like twice the size of the tire. With compound gearing you can take a small drive sprocket to a jackshaft with a larger sprocket, and then on the output of the jackshaft have a sprocket smaller then the one on the input side, and a lot smaller axle sprocket than the 80 tooth that would be needed.

Here, play around here http://www.compgoparts.com/Technical...Calculator.asp
And it'll show you how compound gearing calculation works (plus I'll be honest, I don't wanna explain it while inherited lol)

Basically it allows you to get ratios you couldn't get because of space/size limitations. Or it allows you to get more clearance from your axle sprocket.
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  #23  
Old 08-30-2015, 10:37 AM
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Quote:
Originally Posted by crazykart View Post
Compound gearing allows you to get the same gear ratio as a 10t>80t (8:1) without having to use a huge 80 tooth sprocket on the rear axle.

Say if I had some 10" tall tires, but needed an 8 to 1 ratio (10>80) I wouldn't be able to get that ratio because the axle sprocket would be like twice the size of the tire. With compound gearing you can take a small drive sprocket to a jackshaft with a larger sprocket, and then on the output of the jackshaft have a sprocket smaller then the one on the input side, and a lot smaller axle sprocket than the 80 tooth that would be needed.

Here, play around here http://www.compgoparts.com/Technical...Calculator.asp
And it'll show you how compound gearing calculation works (plus I'll be honest, I don't wanna explain it while inherited lol)

Basically it allows you to get ratios you couldn't get because of space/size limitations. Or it allows you to get more clearance from your axle sprocket.

Ok that make since, where I will have about 12.5 to 13 clearance I will be fine.

So the question I have on the 40 is there place to attach the 10T on the driven. I seen sever pics where the driven is on a
small axle with the 10T. Such as post # 12 on this tread
http://www.diygokarts.com/vb/showthread.php?t=9036
  #24  
Old 08-30-2015, 04:38 PM
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The driven is mounted to a jackshaft, as stated before. On that jackshaft you can have the sprocket anywhere you like. Beyond the jackshaft that the driven is mounted to you won't need any other jackshaft unless you're doing compound gearing.
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  #25  
Old 08-30-2015, 05:23 PM
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Quote:
Originally Posted by crazykart View Post
The driven is mounted to a jackshaft, as stated before. On that jackshaft you can have the sprocket anywhere you like. Beyond the jackshaft that the driven is mounted to you won't need any other jackshaft unless you're doing compound gearing.
OK... Misunderstood... Guess I have been working too many long 15 hours days lately.
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Old 08-30-2015, 08:05 PM
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Lol, you and I both friend.
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Old 08-30-2015, 10:33 PM
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Here a updated picture.

Put in a "bench like" seat bringing it up a bit. Da family insisted
on this as they did want to ride on the ground.

I have the shocks installed on the a-frames. Just waiting for hubs and rim to arrived. Been backordered for 10 days
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Old 08-31-2015, 06:50 PM
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Questions for you folks on the live axle hubs in the rear. I want to go with a 1" axle. Looking at the hubs az2282 has a step down which to my understand you purchase a step down to 3/4 treaded. This axle inserts and stops in the hub which allows one
to place a 3/4 nut on the end.

THere also a 1" live hub with no step down. What stops and holds the axle in place. I think I can place a locking 1" color on the inside but is there a carter pin or clip on the outside?

Advantages or disadvantages over the 2?

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Old 09-02-2015, 10:26 PM
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Was able to put in some nice black spacers I found at the local
farm and tractor supply this week. Below is a pic which I installed
a black spacers on each side of the 12" shock.

Still looking for some 16" shocks for the back of the motor swing on the rear. Have not had good luck in find ones which I can confirm their weigh ratings.
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  #30  
Old 09-02-2015, 11:32 PM
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Why not just lengthen the shock mounts by 2 inches on each end? Would give you the 16" overall length with just using 12" shocks.
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Old 09-02-2015, 11:50 PM
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Quote:
Originally Posted by crazykart View Post
Why not just lengthen the shock mounts by 2 inches on each end? Would give you the 16" overall length with just using 12" shocks.
Oh yea... That makes much more sense and cheaper. Moving them up 2 inches on the back of the kart "seat" area and 2 inches up will bring it up to that 16 inches.

I am considering bringing the point that swivels at the body of
the kart and the swing arms. So when I sit down with 2 of us it
will bring it down. I am afraid of it "sagging" before we start moving. Kind of like what these brothers did.
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  #32  
Old 09-11-2015, 09:53 AM
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Well went to order the axle last night and had the wind out of my sail deflated sorta speaking.

So my width of the front of the cart outer edge tire to tire is 60" So I want to keep the
rear wheels / axle the same width. So I ordered the 22X11 - 8 tires with a 8 hubs 9" wide. From what I read the hubs inside measurement is 4 inches to center. So if my math is correct with a 11" tire on each side that gives me about 6" from the center hub to edge tire. Since there 2 that 12" from the 60" which my calculation I need a 48" axle
shoulder to shoulder.

But the problem is I can not find such beast. Only a 42" which is 40" shoulder to shoulder of the axle. Which will leave me a 4 inch gap at the sides of each tire.

So any suggestions?
  #33  
Old 09-11-2015, 12:12 PM
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the wider your rear axle, the more compromised your steering is going to be.

I found a 54" axle here but that seems pretty wide doesn't it? I hope you were looking for one that has the step on it, otherwise i dont know where to get a super long one. Then again, your kart is wide. Steering is going to be something to work on if you want to keep it so wide.
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Old 09-11-2015, 12:31 PM
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The 54" is way to wide I found this as well.

So if I stick with the 42" (40" S2S) giving me about 52 wide base
in the rear. Will that give me problems since the front is wider
with a 60" front?

I can make some cuts and new welds and take off about 3 total in
the front without major overhall.

I did find a longer axle on bmi but it a 1" with threads and key
but no step down. Which I need to get different hubs and a locking collar for the hubs.
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Old 09-11-2015, 12:37 PM
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The front can be wider than the rear, but not the other way around. I don't know a ton more about it than that. The wider the axle, the more difficult it is to turn.
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Old 09-11-2015, 01:10 PM
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Honestly, I can't figure out if there would be a problem with having either side wider or narrower than the front. Here's why:





If that makes any sense.

On my kart, my front is narrower than the rear.

EDIT: Forgot to add, it also depends A LOT if you have a live axle powering both wheels, or just one.
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Old 09-11-2015, 02:27 PM
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Bmi has a 44" step down axle, and they do make custom length (up to 55") 1" regular axles. They also do all machining in house, so you might want to give them a call, see if they can't cut you one to size, then step and thread the ends for you. It's probably going to cost a good penny, but should be cheap enough.
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Old 09-11-2015, 08:45 PM
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Quote:
Originally Posted by Zombient View Post
Honestly, I can't figure out if there would be a problem with having either side wider or narrower than the front.
There's a lot of physics, math & engineering involved...

Quote:
Originally Posted by Zombient View Post
EDIT: Forgot to add, it also depends A LOT if you have a live axle powering both wheels, or just one.
... & there's the key; the tractor you added has a diff, meaning each wheel can move independantly, essentially making it a single wheel drive...

In simple terms, the wider the axle, the larger the turning circle due to drag (because one wheel is literally being dragged through the corners)...

If the front, steering wheels are narrower than the rear, the drag will seem higher than if they were wider than the rear; not that there is more drag, it will just feel that way; the more you can reduce drag, the better the kart will feel...

Quote:
Originally Posted by crazykart View Post
Bmi has a 44" step down axle, and they do make custom length (up to 55") 1" regular axles. They also do all machining in house, so you might want to give them a call, see if they can't cut you one to size, then step and thread the ends for you. It's probably going to cost a good penny, but should be cheap enough.
For this project, I suggest the beefier 1 1/4" axle...
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Old 09-11-2015, 09:05 PM
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I did get out the grinder and welder and make some changes with the front suspension. By the time I was done I have reduced the
front from 60.5 to 56 from outside tire to tire.

With that said using the stock 44 / 40 S2S + the 12 for tires from
center point. That will give me a 52 and 56 bases. With only 2 inches in on the rear which I can live with.


I have considered the 1.25 axle. But since the 1.25 axle is
a tube thus not solid. I only assume the solid 1" with a step down
was stronger. Plus with the wheel hub with a step down connection seems to me a more sturdy setup than using the
hubs with locking collars???
  #40  
Old 09-11-2015, 09:23 PM
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I may have to come check this out, where ya located? I'm in WVC... with my baby, The Sarge.

http://www.diygokarts.com/vb/showpos...postcount=1448
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