Author Topic: Center Hub Front end  (Read 6759 times)

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Offline oz

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Center Hub Front end
« on: January 26, 2012, 01:38:33 PM »
Does anyone have any Engineering drawings/Schematics to build a centre hub m/c front end. Failing that one they want to get rid of I think yamaha gtr1000 had a centre hub set up!

Cheers Oz
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Offline John Noonan

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Re: Center Hub Front end
« Reply #1 on: January 26, 2012, 01:41:30 PM »
Oz, email Kent from Airtech or Mike Ackatiff


John

Offline oz

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Re: Center Hub Front end
« Reply #2 on: January 26, 2012, 01:43:30 PM »
Nice One cheers John.
Newcastle born and bred a City built on Coal and Steel and a people built of stronger stuff

Offline wobblywalrus

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Re: Center Hub Front end
« Reply #3 on: January 26, 2012, 11:19:27 PM »
The DiFazio, I think this is how you spell it, hub steering system is made in England.  It might work.   

Offline oz

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Re: Center Hub Front end
« Reply #4 on: January 27, 2012, 01:52:40 AM »
Yup wobbly thats the one I managed to find one a few years ago but I seem to remember it was around the 5k price range a little to rich for a man of my means especially when with some rudimentary schematics I could make it myself,Its the way the bearing setup within the pivot/wheel is puzzling me.

cheers Oz
Newcastle born and bred a City built on Coal and Steel and a people built of stronger stuff

Offline Peter Jack

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Re: Center Hub Front end
« Reply #5 on: January 27, 2012, 05:11:41 AM »
Couldn't you run a short hub to one side of the kingpin and then offset the wheel so it's centred back over the kingpin. It would require a pretty sturdy arm or maybe even an upper and lower arm coming from one side to support the kingpin.

Pete

Offline Jon

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Re: Center Hub Front end
« Reply #6 on: January 27, 2012, 06:16:31 AM »
Sounds serious Oz, going sit in rather than on?

Think of the 2 bearings on the cross as top and bottom kingpin bearings.
The angle of them looking from side is your rake & the hub pivots around them when you steer.
Steering rod goes onto one side and pivots the wheel bearing support tube.
Wheel bearings need to be quite big on the ID to allow for steering angle.

Cheers
jon
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Offline Dean Los Angeles

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Re: Center Hub Front end
« Reply #7 on: January 27, 2012, 10:30:34 AM »
It's a simple concept if you think in terms of a conventional set of forks with the pivot moved to the middle of the wheel.
The rake and trail remain the same. It's a simple pivot. As Jon mentioned you need huge wheel bearings to allow enough turning radius.
Hub center steering is the correct term. You get more search results with it.
The real work is in the custom wheel that will fit those bearings.

http://www.tonyfoale.com/Articles/Steer/STEER.htm

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Offline oz

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Re: Center Hub Front end
« Reply #8 on: January 28, 2012, 02:58:19 AM »
The plan is I have are based around a Jawa speedway laydown engine and a eaton blower
 I want to build an A (special construction) with a wheel base as long as I am so I lie flat with just my eyes looking over the top of the front wheel and no point higher than that so starting at the front it really has to be centre hub.
Newcastle born and bred a City built on Coal and Steel and a people built of stronger stuff

Offline Queeziryder

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Re: Center Hub Front end
« Reply #9 on: January 28, 2012, 03:46:39 AM »
Oz
Have a word with some of the sidecar guys
They run something similar which maybe adapted easier.

Neil
Old enough to know better, but too interested in speed to care

Offline Jon

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Re: Center Hub Front end
« Reply #10 on: January 28, 2012, 03:57:08 AM »
Few good pics of a couple Hub Centre setups here Oz.
http://www.dlra.org.au/forum/viewtopic.php?f=18&t=1314&start=90

Sam Wheeler's video clip shows some good pics of his double A arm front end about the 7 minute mark.

I am building a monoshock version of Buddfab's front end.

Cheers
jon
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Offline bones

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Re: Center Hub Front end
« Reply #11 on: January 28, 2012, 04:58:49 AM »
Oz
    There is a huge amount of machening in a hub center. Evering has to be made.
   The Buddfab streamliner's leading link fork does not use a steering head- so height should be ok.
    Much easier to make, standard bike front wheel will work.
   Check the Buddfab site for some pics.
    cheers    Bones

Offline Seldom Seen Slim

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Re: Center Hub Front end
« Reply #12 on: January 28, 2012, 11:43:08 AM »
Don't I remember that Peg Leg Craig's sidecar outfit has center hub steering?  He used to hang around on this Forum - haven't heard from him lately.  Look him up on the "member" listings and maybe you can get some info from him.
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Offline oz

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Re: Center Hub Front end
« Reply #13 on: January 29, 2012, 07:06:02 AM »
Excellent those pics give me a good idea of what i am working towards.
Newcastle born and bred a City built on Coal and Steel and a people built of stronger stuff