mini chopper question

[vengeance]

hello from pa. this is my first post. im building a stretched mini chopper and i have an 8horse motor. does anybody know how if this will go 70 mph with a clutch and sprocket? i never built one before. any advice will help thanks.

 

[vengeance]

pic of what im going buy

hello from pa. this is my first post. im building a stretched mini chopper and i have an 8horse motor. does anybody know how if this will go 70 mph with a clutch and sprocket? i never built one before. any advice will help thanks.

here is what im trying to make

 

[kendelrk]

70mph with 5hp is skeptical, is it a small engine or shifter type bike/dirt bike engine? if your looking for top speed i suggest a torque converter. dont know if you want comet 30 or 40, someone will tell you, but with alot of mods and good parts, you might be able to hit that speed, but not with a centrifigul clutch

 

[vengeance]

im sorry i meant to post an 8horse. i do have a new torque from bulletline its tha same as a30 comet they tell me and im running a 60 tooth on rear wheel but some people say to run a jack shaft for more speed but ive never built anything so im not sure what to do? thanks for the reply by the way

 

[r_chez_08]

hello from pa. this is my first post. im building a stretched mini chopper and i have an 8horse motor. does anybody know how if this will go 70 mph with a clutch and sprocket? i never built one before. any advice will help thanks.

Put a comet 30 series on the 8hp briggs and you may hit 50mph on flat road.
Put a centrifugal clutch on and gear for 70, and within a few hundred yards of clutch smoking and lack of acceleration and your clutch would be dead!
Try looking into a small streetbike motor or highly modified clone or something if you want 70.

However, you say that this is your first build. Can I reccomend gearing for approximately 35-40 mph first, and then you could up the speed if you feel the acceleration is sufficient, and your frame, wheels and driveline can take it.

Please bear in mind: you need to be very good at fabricating if you want to ride homemade toys at 70mph. Please take all neccesary safety precautions like a helmet, gloves and leathers.

 

[kendelrk]

its basically speed= money. how fast can you go? lol. youll need many performance parts and some gearing help from someone on this forum as im not good at it. 70 is a hard number, but with the right amount of money, you can make speeds like such possible

 

[r_chez_08]

im sorry i meant to post an 8horse. i do have a new torque from bulletline its tha same as a30 comet they tell me and im running a 60 tooth on rear wheel but some people say to run a jack shaft for more speed but ive never built anything so im not sure what to do? thanks for the reply by the way

How many teeth does the torque converter have on the jackshaft? Make sure it is the same pitch as your 60t sprocket.

Have you got wheels yet?

A jackshaft is usually used for gearing down for higher torque, especially if you have big wheels or something, because it is often not possible to use a larger rear sprocket because of availability, cost and size problems.
A jackshaft can be used for higher speed, but it is not neccesary and is only adding excess weight.

 

[vengeance]

well the frame and front ed are made from chicago chopperworks.they build real size customs. it has a 6 inch wheel no rubber yet.8 horse briggs. a torque converter no jack shaft so maybe 70 is out of line but 40to 45 would be cool .

 

[Doc Sprocket]

That's a bit more reasonable.

 

[dol-phan007]

well the frame and front ed are made from chicago chopperworks.they build real size customs. it has a 6 inch wheel no rubber yet.8 horse briggs. a torque converter no jack shaft so maybe 70 is out of line but 40to 45 would be cool .

How much did you pay for that frame? Thats nice.