FLAT TRACK BIKE

#41
awesome job Addison for pulling off first place in the main race and first in the heat race Saturday at cedar lake arena on one of my rupp's. kid can drive with only a 196cc grey hound between legs. most of use where only staying for Saturday i do believe 2 or 3 guys where sticking around for Sunday racing. good luck guys and we will see you all at Atwater or maybe torque fest.
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#42
Addison 1place main, awesome job pulling it off at the end. it was a test and tuning night for me with this new motor and it didn't help when Addison ran into to Darrin and knock off the air cleaner. that was about 50 seconds into the video(off camera) and NO i'm not telling anybody what this motor is....LOL Lets just call it the tilly eater. the other two bikes he was racing with where a 236cc 28mm carb and a 225cc 24mm carb(my other bike)
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#45
Awesome job Addison on getting second place in the main and first in your heat. your were creeping up on Jason on the last lap until that lap bike got in the way. man it would of been interesting if they kept the racing at 8 laps for the main. but with curfew they cut the racing down to 6 laps. great job Jason holding off for first. long overdue buddy and jack getting third. it was fun night watching for sure.
Main race

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HEAT RACE.

MAIN.
 
#46
been kind of busy this summer and haven't had much time to post stuff so here is little up date on my flat track racing. earlier this summer we where kick out of AMA because are driver was under 16 and the only reason why was couple guys didn't like the fact a 14yr old kid was winning and guess who? the guy that was in first for points and only buy a little. even though it was a gentlemen's agreement that he could race with us. Well AMA allowed use to vote him back in again buy taking a drivers vote.
kid been winning his last 3 races on my rupp bike.
1st addison tt race 9-11-21.PNG addison first place 9-18-21.jpg addison first place 9-19-21.jpg
 
#48
addison win 10-10-21.jpg
awesome job Addison last weekend. two days of weekend racing. Saturday we were fighting demons with the bike chassis and by Sunday main we were ready to go. also was a testing day for are new motor for next year. which we did not even have it crank up for the race. we just let it idle around the track....lol. couple big thanks for randy and the guys over at dyno cams for welding up and grinding profile i ask for and Max Gregorich rockers. both work out good for this engine build of mine. even though we didn't run a full season of racing we still came out with the most wins, 8 races in are first year of AMA racing.
 
#53
bryan the swing was for a pit bike setup. i had to machine some spacers and weld it up to fit the bike correct. it works like a pit bike or dirt bike setup now. it was crazy how this came together. completely untested bike with the new suspension parts and pulled a retired motor off the self on to the bike just for this bull ring race track. i had only one clean weather day where my road was clear of ice and snow to test run it in a straight line only. still not knowing how well it would corner and all. bike was spot on race day. didn't touch a dam thing other then tire air pressure.
 
#54
bryan the swing was for a pit bike setup. i had to machine some spacers and weld it up to fit the bike correct. it works like a pit bike or dirt bike setup now. it was crazy how this came together. completely untested bike with the new suspension parts and pulled a retired motor off the self on to the bike just for this bull ring race track. i had only one clean weather day where my road was clear of ice and snow to test run it in a straight line only. still not knowing how well it would corner and all. bike was spot on race day. didn't touch a dam thing other then tire air pressure.
I’m going to start a new build based off a 1970 Rupp frame and am looking into what I want to do for suspension modifications I want a longer swing arm and longer forks. Probably will keep dual shocks out back
 
#55
i got lucky with this swing arm. it was the exact length my modified stock swing arm. down fall would be if your going to use a torque converter it will not clear the swing arm. i run a clutch only because of the type of application....racing in a circle(oval track). now maybe and i mean just maybe...lol you might be able to run a 20's series because that driven needs to face in and that might just clear the swing arm. but also the driver now needs to align with the driven. so the engine may have to come to the left more? a lot of if's before knowing it would work with a torque converter?
 
#56
i got lucky with this swing arm. it was the exact length my modified stock swing arm. down fall would be if your going to use a torque converter it will not clear the swing arm. i run a clutch only because of the type of application....racing in a circle(oval track). now maybe and i mean just maybe...lol you might be able to run a 20's series because that driven needs to face in and that might just clear the swing arm. but also the driver now needs to align with the driven. so the engine may have to come to the left more? a lot of if's before knowing it would work with a torque converter?
I will probably stick with a extended original swing arm then. I need to start mocking stuff up and see what’s going to work I will be running a torque converter not sure if ill be going with a 20 or 30 series yet
 
#57
Ok bryan, here is what i had to do to make it work. Made this spacer in the center and welded it into place. Old setup with the steel swing arm i had machine out bearing cups and welded them into place. So the steel swing arm would pivot on bearings and not just the stock bolt and rubber bushing. The stock rubber bushing went bye..bye and i had a solid bushing in place of it. End of last year we were pushing the bike so hard that we would twist the swing arm and through the chain off. Mock-up picture of the spacer in place. New swing arm has high speed bearings in them to pivot on. Also see how close the sprocket is. 18tt 35 chain. you could move it all back ,but you also don't want the wheel base to long either. 20211212_140638.jpg
 
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#58
Ok bryan, here is what i had to do to make it work. Made this spacer in the center and welded it into place. Old setup with the steel swing arm i had machine out bearing cups and welded them into place. So the steel swing arm would pivot on bearings and not just the stock bolt and rubber bushing. The stock rubber bushing went bye..bye and i had a solid bushing in place of it. End of last year we were pushing the bike so hard that we would twist the swing arm and through the chain off. Mock-up picture of the spacer in place. New swing arm has high speed bearings in them to pivot on. Also see how close the sprocket is. 18tt 35 chain. you could move it all back ,but you also don't want the wheel base to long either. View attachment 286580
Yea looks like no room for a tav pulley on that jackshaft. Sounds like I’m really going to have to beef up the stock swing arm or make something from scratch
 
#60
Yea looks like no room for a tav pulley on that jackshaft. Sounds like I’m really going to have to beef up the stock swing arm or make something from scratch
there is so much plus+ with the new swing arm. wheel adjusters, floating brake setup if the wheel and axle/chain gets adjusted the brake still stays the same,light weight arm and super strong. single shock setup...etc.. if you do build it out of steel? just try to incorporate the same stuff as the aluminum's have.;)
 
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