Building minibike

[inspire_biraj]

Is it possible to build minibike with Small generator engine?Plz help me with this. What should be minimum requirement of engine to carry load of approx. 120 kg

 

[landuse]

A generator would work fine. You just have to make sure that it has a straight, keyed output shaft. Generators sometimes have a tapered shaft, and you cannot put a clutch on those. I would say about 3HP would be the minimum (geared low 10:1)

There are many other factors that might influence the decision, like tyre diameter being used

 

[inspire_biraj]

I am using 8 inch tyres and the total load of frame is approx. 25kg

 

[inspire_biraj]

Previously I used grass cutter engine, 32.8cc,1.4hp,7500rpm and i didnt succed.Here are the pic

 

[landuse]

Previously I used grass cutter engine, 32.8cc,1.4hp,7500rpm and i didnt succed.Here are the pic

Yup, I think you are goingto have to use at least a 3.5HP engine. You will have to gear it low for it to have any torque and move you. With 8 inch tyres you will have to use a jackshaft I think. You could try a 10T clutch and 60T back wheel sprocket. You might get away with a 6:1 ratio

 

[inspire_biraj]

Actually what matters to carry a load? Horsepower or Displacement ?

 

[landuse]

It is hard to say which is better, because there is no direct correlation between the two. For example, a 202c Predator engine is 6.5HP, but a 200cc motorbike engine can put out like 30HP.

The higher HP is probably what you are looking for, but I wouldn't get too big an engine for that small frame. 6.5HP will be more than enough.

 

[OzFab]

Actually what matters to carry a load? Horsepower or Displacement ?

As landuse explained, displacement does not control horsepower so, horsepower is more important...

For what you have (nice bike by the way) I'd suggest a maximum of 5hp. Although your little 32.8cc grass cutter engine only produced 1.4hp, a 49cc pocket bike (mini moto) engine will produce around 5-6hp

 

[tractor guy]

I had an old APC mini chopper with a 49cc engine like this one. I dont know what the gear ratio was but with me (200pnds) and my heaviest kid (50-60pnds) it would do around 10-15 mph (struggling on the hills). I dont know what the hp is outta these things but they work fine.

 

[inspire_biraj]

Ok, I am going to try it again with more bigger engine.Thanks all

 

[firemanjim]

http://www.diygokarts.com/vb/attachment.php?attachmentid=42364&d=1384866402
That tire/sprocket came from a 49cc pocket bike. All you need to get your bike moving good is the correctengine and clutch set up..... I will find/post a link to what you want shortly. They are cheap and work great. It the same engine i used on my daughters mini kart. Watch the videos i posted. It pulls me with ease and fast. The vid with me riding is ONLY half throttle due to no brakes at the time....
http://m.ebay.com/itm/400508944848?nav=SEARCH&sbk=1
Thats a hi-po/pricey one.... but would work great as a drop in/bolt up swap...
http://m.ebay.com/itm/330680547281?nav=SEARCH&sbk=1
That one is exactly like mine.., works great...

 

[BuckhunterMN]

Torque, is what moves your Mini, Gear it right and you will be fine. BuckhunterMN

 

[DMCdesign]

Biraj, I am frightfully keen on that grass cutter engine. Do you have it with you?

EDIT: I live in UTTRAKHAND, and he lives in NEPAL, so it might be easier to ship the engine here........