December 29, 2014 at 10:21 am #39555
These are YouTubes of a shifter Kart and a clutch Kart I setup with hand controls for a T4 paraplegic (arm pits down). I made these videos back around 1993 for some guys that wanted more information about my karts, I ran across the VHS tape a couple a day ago and put it on YouTube. I raced shifter Karts from 1993 to 2004 , I had to quit because it was damaging my shoulders. I was thinking someone looking for hand controls information may find it useful.
shifter kart setup
Clutch Kart setup
December 30, 2014 at 3:25 pm #39666
In the video of the shifter kart I showed the arm rest with the red pads that I put my elbows on to hold my body in corners. From 1993 to 2000 the tracks I raced where slick because of asphalt sealants that where on the tracks. The arm rest worked well on slick tracks , when I put my elbows on the arm rest it transferred weight to the rear of the kart and increased the traction on the rear of the kart. This system work great on slick tracks.
In 2000 they had a company grind the track surface so the track had a lot of surface traction. This caused problems with using the arm rest, when I put my elbows on the arm rest the kart would jump and lift up on 2 wheels. I tried all the set up tricks to remove traction like removing torsion bars,
loosen bolts on bumpers, soft axles, removing seat struts. All this stuff helped but the kart still had to much traction when using the arm rest. So the arm rest need to go.
I got a RIBTECT seat and used it for the bottom part of the seat ,I did not do any cutting on this seat , I used the whole seat. The seat in the videos is a Pro-Rib seat I got it from Power Sports Racing, I cut the top
half of this off , so I could mount it on top of the RIBTECT seat. I used flat band steel 0.125 thick and 1.5 inch wide about 18 inches long and put it on the outside of the seats so I could bolt the seats together one on top of the other. I used 5 straps bolted to the seat with 4 bolts in each strap ,2 bolts go into the lower seat and 2 bolts in the upper seat on each strap. I played with cutting the upper half the seat to get it so it came to my arm pits, I played with bending the steel straps to get the right angle between the seats. Then I went to the track to test it and make more adjustment. Then took the seat off the kart and lined the inside with poster paper so the inside surface was smooth over the whole seat. Then I took the seat
to a fiberglass shop and had them make mold of the inside of the seat . Now I had mold the shop could make seats from, I kept the mold so I could have a new seat made each year . The bottom of seats take a beating when they touch the track and would only last about 1 season. I did some testing with having seats built with different thickness to come up with the that worked best for me. If the seat is too thick it will mess up the kart handling. Also the seat in the videos has bump up area in the back that helps
support the neck , the new seat also has this same bump up , I needed it to support my neck area.
The new seat improved the kart handing. I still had to use all the set up tricks to remove traction like removing torsion bars, loosen bolts on bumpers, soft axles, removing seat struts. A seat that has sides that come all the way to your arm pits, has the effect of a increased lever arm and put more load into the kart frame, this causes the kart to have more traction in corners. This new seat worked better than the arm rests , the kart jumped less and went up on 2 wheels less in corners. I came up against a speed limit in this set up, the fast guys ran low 36 second lap times , if ran faster than 37.5 second lap time the kart would jump and go up on 2 wheels in corners. I tried all the tricks to reduce traction but could not over come this traction problem on tracks that surfaces with a lot traction. The problem got worse on race day when all the karts lay rubber on to track surface.
I changed how I did brake bias from the video , I went to using pressure reducing valves made by Stainless Steel Brake Corp I got them from Racesparts Wholesale part number SSB-1000, these are in line pressure
reducing valves that have a little size. They have a knob you can turn to reduce the pressure your brake line hose by up to 60%. I mounted 2 of them my steering wheel , one for each master cylinder. I ran a 6 inch
brake line from each master cylinder to each pressure reducing valve. Then I connected the brake line hoses coming from brake calipers to the pressure reducing valves. So I one pressure reducing valve in the brake line going to the rear brakes and one pressure reducing valve in the brake line going to the front brakes. With this set up I could turn the knobs on the steering wheel while I was out on the track driving to adjust the brakes, this system worked great.
I am T4 arm pits down no working muscles , any muscle that crosses line of my arm pits does not work. Supporting my upper body in the kart was my major goal in setting up a kart. The things you do to support upper body will mess up the how the kart handles on the track. Karts pull high side loads
and if your body is not supported you will not be able to drive. Paraplegic with a lower injury like close to the waist level would likely not have a problem and could use a normal kart seat with no other support.
You will need to put a bungee cord across the front bumper over your legs, to hold your legs in the kart. If you hit a big bump in the kart your leg can bounce out the kart, this happen to me, I got lucky and did not damage my leg.
I used a Velcro round my legs up where my legs come out of the seat near the gas tank to keep my leg away the exhaust pipe on my shifter, in corners your leg whats to slide toward exhaust pipe. I got third degree burn on my leg from the pipe, my leg slid 8 inches over onto pipe due to cornering forces when I burned my leg.
I do not have pictures or video of the changes I made to the kart after the time the video on YouTube where shot.
The Clutch kart video is kart with a KT-100 Yamaha motor, I did not need arm rest supports like I used on the shifter kart . On this kart I did use a PRO RIB seat that I got from Power Sports Racing, this seat does come up a little higher on the sides than a normal kart seat. I only used this Kart a few months got bored with it and moved to shifter karts.
January 2, 2015 at 10:31 pm #39811Walt GiffordParticipant
We had a guy like that down here. Had a rat kart with a clone motor set up with extra side pods to keep his legs in place. He drove his own car to the track too. I guess karts are the ultimate mobility devise. Nice guy, haven’t seen him around lately.
FAA certified jet engine and aircraft technician,
Nicholson Speedway class champion 2001,
Yamaha KT100 Service Center,
41 years karting experience
January 3, 2015 at 8:58 am #39818Jay SinonParticipant
Just shows ingenuity goes a long way if you want something bad enough.
January 3, 2015 at 1:34 pm #39829Michael ZahorskiParticipant
I know Eddie Lawson helped setup a 250 superkart for Wayne Rainey a few years back. He strapped in and used motorcycle hand controls.
January 3, 2015 at 6:23 pm #39843
The tracks where I was racing told me no handle bars allowed, I had to have a steering wheel, they said handle bars could impale my body in a crash. They told me no air shifters of electric shifters had to be a mechanical shifter.
So any body building a handicap Kart need to check with the tracks where they plan to race to see what they will allow before building a Kart up.
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