One man's idea is....

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REAR
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Joined: Sat Jun 16, 2007 10:19 am

One man's idea is....

Post by REAR » Tue Dec 01, 2015 7:32 pm

The great thing about preserving American Kartings early years is that it allows us to look at many different design concepts that were tried in the quest for the ultimate handling machine

At this years running of THE BIG ONE Chris Marchand brought a very unique Kurtis Kart designed by championship race car builder Frank Kurtis that he acquired from Dave Bright in a kart buy out.
Unlike fellow race car builder Jim Rathman who chose a monocoque type rigid design for his Exterminator kart Frank Kurtis tried to employ torsion bars and friction dampening into his chassis.

Take a look below and notice how the torsion bars are mounted along with the adjustable friction dampeners on the front axle allowing for adjustment of the front axle spring rate while the rear wheels are also sprung and dampened on their own axle independent of the front axle allowing for their own adjustments.

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Don't know how well the chassis worked out but it is a great example of one mans attempt at a better mouse trap. If trends and progression are any indicator the idea may have looked good on paper and had sound engineering minds behind it but it obviously did not produce the results that Mr. Kurtis had hoped for.

A nice side note to this story is that Don Thompson out of Illinois ended up taking the kart home with him. Lets all hope Don does one of his super restorations on this kart and brings this great American karting chapter back to life.

R.E.A.R.

ted johnson
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Re: One man's idea is....

Post by ted johnson » Tue Dec 01, 2015 9:11 pm

I imagine the main reason for Kurtis doing the kart this way is that the suspension, brakes and general design were all inspired by, and lifted from the Kurtis-Kraft series of quarter and half midget racers from the fifties and early sixties. I raced QM's, and there were several Kurtis-Kraft cars in the group I raced with. This was all before karts came around. The QM's were somewhat successful, though there were better QM's like the Moss. The only time I drove one of the Kurtis Karts, it was HORRIBLE. It had an AU-8 Continental with a built-in 6:1 gear reduction, and ran and drove like a tank. As bad as the Xterminator was, the Kurtis was worse! http://www.forgottenfiberglass.com/fibe ... -cars-too/
Ted

Chris Marchand
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Re: One man's idea is....

Post by Chris Marchand » Tue Dec 01, 2015 10:57 pm

We assumed this was a Qtr Midget chassis because there were numerous nerf bars with the frame. And just looking at it, it looks like it would handle like a tank .

ted johnson
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Re: One man's idea is....

Post by ted johnson » Wed Dec 02, 2015 9:32 am

Chris, back when I first ran a QM in 1951 (I was seven), there was a league in Brevard County, Florida. The auto dealers had a set of common plans, and had local shops fab the QM's to the plans. They had no rear suspension, a transverse leaf front spring with friction shocks, and the first ones had a hand brake. Pop built one for Newell Ford, and it had a foot brake and telescoping shocks (WOW!). I got to drive it for three seasons, '51, '52 and '53. I won my fair share of races, but finally decided that QM's were boring, so I quit the series. I still went to the weekend races at the 1/10 Mi. Melbourne airport track, so I got to try out several factory built midgets in the later years, including the Kurtis, Moss and Larc-Douglas cars, as well as Pressweld's ill-fated attempt. The Moss was the best of this group, though the locally built cars with several years of development behind them did very well indeed. As I remember, they had a live axle, but the inside wheel had bearings so it rotated independently from the axle. Since they only ran on either a 1/20 or 1/10 mile oval, that worked O.K. They all ran a Continental Red Seal engine with a gear reduction box. I remember when we were in our first few years of karting that Pop and I discussed getting a Moss 1/2 midget, but my memory of how boring the QM's were caused me to talk him out of it. Ted

REAR
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Joined: Sat Jun 16, 2007 10:19 am

Re: One man's idea is....

Post by REAR » Thu Dec 03, 2015 7:46 am

Don't know if it handled like a tank but can sure tell it weighed as much as a tank. Had a hell of a time just moving it around to get some photos,

Food for thought on the swing-arm style rear suspension concept. In order to correctly adjust the chain for tension you have to check the slack at compression of the rear end so you would need the driver seated and actually bouncing some to get the right adjustment. This adjustment would have been very critical due to the poor quality of chain that was available during this karts time frame.

Karting....Made in America

R.E.A.R.

dave bright
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Re: One man's idea is....

Post by dave bright » Mon Dec 14, 2015 9:39 pm

I sure would like to see it when it's restored. Liked it but its too small or I'm too big.

tom kelley
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early seventy's bug
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Re: One man's idea is....

Post by tom kelley » Fri Jan 01, 2016 6:50 pm

just a little update....
don and i dropped this off at a good friends house and the Thompson ,Sheridan,Kelley kurtis kart may actually be up and running for the big one 2016
tom

ted johnson
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Re: One man's idea is....

Post by ted johnson » Fri Jan 01, 2016 9:58 pm

Tom, what'll you install for a power plant? Lots of them came with Continental Red Seal engines, but that wouldn't be appropriate for TBO! It ought to have a torque monster like a PP AH-81 or a West Bend 700. What would be coolest would be one of the 7+ cube saw engines like one of the big Titan, Remington or Mall saws! http://www.acresinternet.com/cscc.nsf/G ... r?OpenView
Look here. You can find some big beasts worthy of the Kurtis. Ted

tom kelley
Posts: 17
Joined: Fri Apr 11, 2014 10:16 pm
Vintage Karting items owned: 1961 rupp
early seventy's bug
sweet modified yard cart turned racer
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Re: One man's idea is....

Post by tom kelley » Sat Jan 02, 2016 4:56 pm

ted,
we have pictures with them with a clinton on it
so that's probably what will go on it
tk

REAR
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Joined: Sat Jun 16, 2007 10:19 am

Re: One man's idea is....

Post by REAR » Sun Jan 03, 2016 8:54 am

Its great to hear that this kart will be saved because bringing these old karts back to life is what this hobby is all about and knowing the cast of fellows involved in this project its a pretty safe bet that we are going to be in for some real eye candy that will be returned to its past glory.

R.E.A.R.

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