Kart race engines vs. the big displacement....

medusa51 said:
I was into 1/8 scale RC racing in 1990 and they had 2 speed and 3 speed clutch's I always wondered why nobody ever tried it on a kart. And 4wd! Just driving a awd over a rwd you could see a big advantage. Maybe we need awd karts. lol
Click to expand...
Don't know how well it worked, and huge scrub radius, but.....
1603110203502.png
 
On a fast dry track like most Main events are in the South you might be well slower with 4wd (extra weight, etc). Remember the WRC (Road Rallies) been beaten on asphalt by 2 wheel drive Kit Cars with less power than them.
 
How about a worm drive off the crankshaft or jack shaft to a small differential via viscous cuppler. I still can't figure how to match a gear ratio change
 
Jim46 said:
How about a worm drive off the crankshaft or jack shaft to a small differential via viscous cuppler. I still can't figure how to match a gear ratio change
Click to expand...
Make the ratio from the jackshaft the same to each axle.
Adjust drive ratios at the engine to jackshaft chain.

Pretty much what every 4 wheel drive does.
 
I know this is an old thread and I should probably keep my mouth shut, but I can't...how about this 500cc max displacement and no minimum weight?
 
Back in the days of ole, we used to race WKA open 2cycle dirt at the old Travlers Rest Speedway north of Greensboro SC, 300cc weight was 300#, 135 was 330#, 150 was 350#. This was before jackshafts were around, so we ran 4 shoe oil clutches outboard except for the rotary valves (B-Bombs & T-60 Daps). Chris was in his teens and weighed about what Evan weighs, he'd show up with his girlfriend and a Margay Expert with a KT-100 stocker, I was helping 3 other drivers and building their motors, a K-35, K-30 & a T-60, out my junk I ran occasionally an Expert with a .010" over piston, but I weighed around 340#, Chris & I couldn't run with 135s and there was an LMR 100 reed that usually outran us, it's was around 115cc so they say. I decided to juice up my Kt-100, somebody gave me a used superstar 5 shoe clutch so I made it a 3 shoe and did away with the finger spring plate, up the compression, did some porting and milled off the fins around the intake and made an adaptor to put a Gem v-12 reed for 101 Mac on it and put HK 34mm Tilly on it, and I cut the chamber and added about an inch to the center section equaling it to the 135cc open pipe, it would then run in the top 5 and got me 3rds. Chris & I usually ran a 9-71 gear package when both KTs were piston/port motors, after my mods I could run a 10/69 gear. I tried to get Chris to run my kart since he would be around 305#, but he wouldn't saying he wouldn't want feel responcable if it blew up or something. I wanted to see David Wadell and Larry Perkizer's 135's finish behind a KT-100.
 
possible but not worth it.. imo.. not enough cylinder to bore at least 4mm, and compressible volume will require a lot of change in head..
which is why I built the first billet 250..
 

Attachments

  • mikes cases 003.JPG
    mikes cases 003.JPG
    88.2 KB · Views: 26
Last edited:
Sledge, Kermit Buller did one about 4or5 years ago billet bottom end 150 they had trouble with the rings . Mike, I've got one that we been playing with for 2years pictures are on here somewhere. later Chuck.
 
nobozos said:
Sledge, Kermit Buller did one about 4or5 years ago billet bottom end 150 they had trouble with the rings . Mike, I've got one that we been playing with for 2years pictures are on here somewhere. later Chuck.
Click to expand...
Not all the 150s were billet, Chuck, and there were bigger issues than just the rings, like with any engine you bore. when the sleeve gets too thin heat dissipation is usually an issue. Added to that if bore or capacity would always be effective most 100cc would be very slow on any surface and they are not. On sprint tracks modern rotary valve SA and FA were faster than previous engines with bigger displacement, and faster than modern 125 TAGs too. Obviously at long oval tracks power can be effective from a big engine... as long as it stays together.
 
Yo Rain take a look at the one pictured above ∆∆∆∆∆∆∆∆ that's a 149 call it a 150 of a buddy of mine no billet bottom end. I never said all the 150's were billet .Have a safe trip to Spain for Christmas I don't think that they are gonna let you back in the U S A even though you are a citizen now. I'll have my people talk to your people lol later Chuck.
 
nobozos said:
Yo Rain take a look at the one pictured above ∆∆∆∆∆∆∆∆ that's a 149 call it a 150 of a buddy of mine no billet bottom end. I never said all the 150's were billet .Have a safe trip to Spain for Christmas I don't think that they are gonna let you back in the U S A even though you are a citizen now. I'll have my people talk to your people lol later Chuck.
Click to expand...
They will. They don´t want me anymore overseas now that I am American. Package will say Return to Sender, lol.
 
ECkarter said:
Don’t forget the Tal-co 150
Click to expand...
If I am not wrong the Tal-co was a piston port engine. I don´t think it had more power than even the good JICAs, much less a reed or rotary. At least not same performance. It was affordable I think though.
 
rainman said:
If I am not wrong the Tal-co was a piston port engine. I don´t think it had more power than even the good JICAs, much less a reed or rotary. At least not same performance. It was affordable I think though.
Click to expand...
The TKM BT82 is the engine you are thinking of. And they were just about as equal as any other jica. They have a modern version still made today. TKM also made several reed and rotaries. The TKM R135 was available with bores from 135-150cc.
 
You must log in or register to reply here.
Back
Top