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Discussion Starter #1
Haven't seen a thread about these yet and I'm in the market and don't know squat about them really. I figure they're like anything else, they depend on alot of other factors but I'm just lookin for some basics, and figure this could benefit others b/c they've come up in a few threads recently.

My specific application will be going on a 4mil cub, stock frame, +6 swinger, possibly a +8. I weigh around 145lbs. so it usually takes quite a bit of paddle to get some hook. I figure i'll end up with some 12 pdl extremes or possibly 14 pdl setup. I'm just lookin for some simple things like general length, height, etc. Any info is welcome.
 

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On my bar's from what i have read and seen alot of people make there bar length the same or about 6" longer than there wheel base but that is what i have read.

I use 3/4" .049 wall tubing for the bottoms and a 3/4" .065 for the top bar on the 4 bar and on the 3 bar i use a 1" .065 bar for the top and a 3/4" .049 for the lower's.

I will be making one for my shee in the next week or so and i will post up pick's when i am done with it.

On the height you want to be able to set a coke or beer can under the tire when the bike is sitting @ rest.
 

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i use a single top bar thats 1in 058, and the duel lower bars are 3/4 058......i make mine from 6-6.5 inchs. the longer the bar the more forgiving it is..... the one i built is fully adjustable with a start ride heigh of 4 inchs off the ground..



 

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Discussion Starter #4
I was thinking I would probably do the single upper too. I want to make it adjustable for different swingarm lengths as well and have a few ideas for this.

What kind of wheels are used and where can you find them?
 

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QUOTE (okbeast @ Jul 17 2008, 08:21 PM) index.php?act=findpost&pid=5715I was thinking I would probably do the single upper too. I want to make it adjustable for different swingarm lengths as well and have a few ideas for this.

What kind of wheels are used and where can you find them?

i have a go cart tire on mine.
 

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yeppers, go kart wheel....not sure of the size but its a front wheel and tire, not a rear. I guess you could use a rear, they are just a touch wider..
 

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QUOTE (blasterman88 @ Jul 17 2008, 08:55 PM) index.php?act=findpost&pid=5713i use a single top bar thats 1in 058, and the duel lower bars are 3/4 058......i make mine from 6-6.5 inchs. the longer the bar the more forgiving it is..... the one i built is fully adjustable with a start ride heigh of 4 inchs off the ground..






are you struting your bike up when you run the bar.... if not the top tube going to the sub frame is not going to work to well with a shaw I dont think. you would need to bolt it to the swinger.....

anyways very nice bar.... I like it.
 

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I have built many wheelie bars and rode a few also. I will give ya a little insite..

The single upper bar is fine and they work great but, When you use two smaller uppers it actually is a smoother transition on and off the bar. meaning when the wheel touches the ground the two smaller bars flex more and makes the the trasition a little less noticable. Also it seems like the the two upper bars gives you more stability side to side. I know these are trivial but beleive me you will notice the difference.
on my bike I would not put the tube between the upper and lower tubes. you get more flex that way and it is much more comfortable. feels like a "lazy boy", but you need to watch that on single upper style bars.. the bar can twist easier if you get side ways.
You will need to tie the top bars together with a tube and tie the lower bars together with a tube. this will stop the bar from twisting.
The single upper bar is always easier to build and maybe a bit lighter, but i think if i was going to build any more i would only do the twin uppers.

ATV drag Wheelie Bar **NOTES**
Always use heim joints to attach wheelie bars, Never rigid mount to chassis
Never allow people to grab and pick the bike up with the wheelie bar, unless they are at the very back near the wheel.
Always check the bearings in the wheel before every race weekend.
Check welds for cracks before every race weekend.
try to use continueus bars for upper and lower tubes with min welds, if you must weld cros bars extra, never weld completely around the bar.
Your wheelie bar legnth should be a min of your wheelbase.
NEVER use mild steel or conduet for your wheelie bar!
attachment points on bike should be your rear carrier since bolts and a point high on the subframe.
If you are running a shock, NEVER put a brace between the upper and lower bars.




tubing sizes, 4130 Chromoly
twin uppers use 3/4" dia .065 lowers 3/4" dia .049
single upper use 1" dia .065 lowers 3/4" dia .049
Wheel should be light but as wide as you can get. You must use a bearing on your wheel, No bushings.
 

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So on the uppers should you run a brace between them like you would on the lower's to keep them from bowing out or in?
 

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Discussion Starter #14
QUOTE (BBIII @ Aug 6 2008, 12:24 PM) index.php?act=findpost&pid=7612So on the uppers should you run a brace between them like you would on the lower's to keep them from bowing out or in?

Majority of the uppers I have seen are individual pieces. I would imagine that if you got all your geometry right and cut everything to close tolerances you wouldn't have much horizontal displacement.
 

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I've built a few bars and agree with everything Ziggy said about 4 bars vs. 3, the most forgiving setup is 4 bars. I've tried a few times to get a 3 bar to work but they would dart to one side or the other sometimes and it had nothing to do with them being built or installed straight, a little rut or one tire hooking harder is enough to upset a 3 bar system in my experience. Once you start going crooked with a wheelie bar, the quad tries to turn on the inside rear tire and things get ugly fast, the extra weight of the 4th bar is worth the launch consistency in my opinion.

I make the upper bars out of 1" .058 and the lower bars out of 3/4" .058. I used to make the upper bars out of 3/4" .058 but bent them on a longer wheelbase chassis, 1" .058 is strong enough not to bend but still has some flex. I don't tie the upper bars together but the bottom bars are tied together.
 

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QUOTE (UBETRUN @ Aug 9 2008, 10:07 PM) index.php?act=findpost&pid=7820I've built a few bars and agree with everything Ziggy said about 4 bars vs. 3, the most forgiving setup is 4 bars. I've tried a few times to get a 3 bar to work but they would dart to one side or the other sometimes and it had nothing to do with them being built or installed straight, a little rut or one tire hooking harder is enough to upset a 3 bar system in my experience. Once you start going crooked with a wheelie bar, the quad tries to turn on the inside rear tire and things get ugly fast, the extra weight of the 4th bar is worth the launch consistency in my opinion.

I make the upper bars out of 1" .058 and the lower bars out of 3/4" .058. I used to make the upper bars out of 3/4" .058 but bent them on a longer wheelbase chassis, 1" .058 is strong enough not to bend but still has some flex. I don't tie the upper bars together but the bottom bars are tied together.Are you running a single wheel or two wheels on the four bar wheelie bar? I`m trying to build on for asphalt!
 
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QUOTE (neely97 @ Nov 6 2008, 10:30 AM) index.php?act=findpost&pid=15113Are you running a single wheel or two wheels on the four bar wheelie bar? I`m trying to build on for asphalt!
For asphalt. Always use a single wheel. Never use a setup like what is on a drag bike.
 

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QUOTE (Planet Asphalt @ Nov 6 2008, 09:04 AM) index.php?act=findpost&pid=15116For asphalt. Always use a single wheel. Never use a setup like what is on a drag bike.So is a three bar or a four bar setup better for asphalt? I have a three bar and I have big problems with the bike changing directions left or right! Also what heigth do you have the wheel of the pavement with the bike at rest with rider on?
 
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