Choosing the right engine?

[cojaro]

Well, I've found a place that sells a 49CC minibike engine for $100 + s/h.

Will that be strong enough?

here it is - http://www.giovannibikes.com/bikeparts.php

 

[imported_robertdjung]

You'll also want to know what kind of clutch it takes, what kind of chain, mounting holes, price of clutch, etc. The pic of the clutch they list is just the insides of a clutch --- i didn't see a housing, sprocket, etc.

I'd still get a cheap engine from pep boys, costco, etc.

 

[cojaro]

Well, once my minibike is finished, it'll be about 150-200lbs w/ me on it, i'll buy the clutch and stuff separate. I'm planning on a 12tooth drive sprocket connecting to the 60tooth sprocket I already have.

Think it's strong enough?

 

[imported_robertdjung]

I guess I wasn't clear -- what I'm saying is that engine might not use the same standards as a normal engine... You've got to know the output shaft diameter and whether a standard clutch will fit on it -- or you've got to find out if they sell a clutch and a sprocket that goes with it.

 

[jrjulien1]

i dont think that the 49cc engine would be up to the task of pushing 150 to 200 lbs up hills and such unless you used a very low gear ratio resulting in a low top speed in other words dont mess with these small engines use something between 3.5 and 9 hp for your minibike because not only will you have a higher top speed and more low end torque it'll be easier to find replacement parts for the engine and clutch should anything go wrong

hope this helps

 

[cojaro]

Then I guess a 3.5-6.5 hp engine is in order.

Costco has a 6.5hp engine for US$150. w00t.

 

[mikeandike]

wen i bought my engine at costco i got it for US$117

 

[cojaro]

wen i bought my engine at costco i got it for US$117

Is it the 6.5hp Champion engine?

 

[mikeandike]

yeah

 

[jrjulien1]

iv bought an entire go kart frame with tires and an old fiberglass body for 50 bucks and it had a 5hp engine with it the only thing that was wrong with it was the sterring and no brakes
Woot

 

[cojaro]

iv bought an entire go kart frame with tires and an old fiberglass body for 50 bucks and it had a 5hp engine with it the only thing that was wrong with it was the sterring and no brakes
Woot

Good buy!

 

[jrjulien1]

ya i bought it from a friend of my dads i sold it a while ago tho it wasnt big enough for me anymore as im 6 foot 2

 

[cojaro]

ya i bought it from a friend of my dads i sold it a while ago tho it wasnt big enough for me anymore as im 6 foot 2

I should have any problems like that, since I'm only 5'4"

 

[jrjulien1]

ya thats the main problem i have ordering anything pre built for a kart or minibike is that most frame parts or frames are too small for me so im mostly stuck building my own stuff

 

[joe]

49 cc go cart will do about 35 mph with 160 lb man . that is with the stock 19 tooth to 44 tooth sprocket (the chain is like a 15 or 20 ,it's realy small ,smaller than a bike).this setup will only give you about 45 mph on a small minibike. that is more than enough for small kids (65 lb to 160 lb) but for the money the 6.5 h.p engine sounds like the best bet

 

[jrjulien1]

the thing about the 49cc isnt the top speed that you get its the torque that you get as those engines turn fast but dont make very much torque which would make acceleration and uphill travel difficult

just another reason a 6.5 or bigger is better