What could possibly go wrong?

well the little 29cc bike is being retired. it is a sad day.

BUT, dont fear, my projects always come back better.

in this case, i have an almost brand new 5 hp briggs. it has less than an hour of use, and looks factory, no dents not even any dirt packed in the fins, it just happens, that it will fit in the frame of the old 5 speed bike. now i know what you all want to know, and that is, it it gonna have gears? that is a definate yes. i feel that with this power, the gears are gonna be fairly shallow, but i have an idea to combat that. it is gonna be a street bike, as much as that pains me, but the casette doesnt have a creeper gear. i did the math, and i need a 6 to 1 for dirt use, but that will be very hard to make. i can make an about 5.5 to 1. (with a jackshaft) which should work ok. im gonna have about 65 ft lbs of torque, and with pedals, you can make more, so i hope i wont break the chain. its gonna have a centrifugal clutch, because there is no room for a cub cadet, or belt clutch. im gonna leave the governer in, and leave the engine 100000% stock. i need help connecting the throttle cable, on the below tank bracket. i really need a picture. speaking of pictures, i have mocked up the engine. let the build begin.

I am open to any advice, from the people that know about high power, and gears.
 

Sidewinder Jerry

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well the little 29cc bike is being retired. it is a sad day.

BUT, dont fear, my projects always come back better.

in this case, i have an almost brand new 5 hp briggs. it has less than an hour of use, and looks factory, no dents not even any dirt packed in the fins, it just happens, that it will fit in the frame of the old 5 speed bike. now i know what you all want to know, and that is, it it gonna have gears? that is a definate yes. i feel that with this power, the gears are gonna be fairly shallow, but i have an idea to combat that. it is gonna be a street bike, as much as that pains me, but the casette doesnt have a creeper gear. i did the math, and i need a 6 to 1 for dirt use, but that will be very hard to make. i can make an about 5.5 to 1. (with a jackshaft) which should work ok. im gonna have about 65 ft lbs of torque, and with pedals, you can make more, so i hope i wont break the chain. its gonna have a centrifugal clutch, because there is no room for a cub cadet, or belt clutch. im gonna leave the governer in, and leave the engine 100000% stock. i need help connecting the throttle cable, on the below tank bracket. i really need a picture. speaking of pictures, i have mocked up the engine. let the build begin.

I am open to any advice, from the people that know about high power, and gears.
My personal choice for a bicycle chain is a Shimano HG71. I also like using a Sram X4 rear derailleur and shifter. With a 5 speed it's more than likely a freewheel not a cassette. You may want to consider my 4 speed freewheel. You should be using double walled rims and get a rear cro-molly axle. The stock axle will be prone to bending. If you're going to be off roading, then switch from the freewheel hub to an actual cassette hub. Get a suspension seat post as well.

Thread '4 Speed Freewheel' https://motoredbikes.com/threads/4-speed-freewheel.58615/
 

redneckracing674

Active Member
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Dec 18, 2021
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211
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Lancaster SC
i am using the rear wheel out of a giant sedona. it has (pre) deoore components. im guessing it has a cromo axle. it has exgage 4000lx componenets if i remember right, and they are deore, rebranded. all decent mtb stuff. aluminum rims ok? or double wall steel ones. they are tubless hook bead if i remember right.

i have kmc hp chain. it is in spec. not very stretched
 

darwin

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Where ya going to put your feet?
side-view-beautiful-african-american-woman-riding-bicycle-her-legs-handlebars-beach-150365452.jpg
 

Wrench

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so cal
He's just gonna have to make foot pegs Because no way is he gonna look as good as that Chick riding that bicycle
 

redneckracing674

Active Member
Local time
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Joined
Dec 18, 2021
Messages
211
Location
Lancaster SC
im gonna either put my feet near the rear tire, or put em below the motor. i might put some pedals on the jackshaft ends, and burn out the bearings lol. i cant do that i already tried on my friction drive setup.
 
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