What stops you from using dirt-bike engines?

Legality, probably. A 69lb 200CC engine with transmission combo? Almost 16" wide? That's for a little motorcycle.

Not too many use shifter kits on the HF engines. In fact, I don't think I've ever seen one.

Motorized bicycle/ motor assisted bicycle=having PEDALS
no pedals its a motorcycle

I don't think it's a better idea at all. Putting an engine that large on a bicycle is a bad idea, if you ask me.

Might as well get a motorcycle. Stronger, more powerful, legal. But greed rules in this day and age.

Like Aleman said legality. In Texas that bike would be considered a motorcycle, even with peddles.

OTOH if you're planning to make a motorcycle that motor would be alright I guess.

Big motor.... better have even bigger brakes

right now I have a ktm 250cc and a honda 125cc dirt bike motors and I will not use either of them in a bicycle frame as the frames will NOT hold up under that amount of power. People break bicycle frames with Just a 48cc 2stroke Ht. What do you think a 250cc 2stroke would do to the same frame?

Cavi Mike said:

With the amount of work I see you guys put into squeezing some of the most ridiculous engines in your frames including building frames from scratch, what stops you from just getting something like this?

Click to expand...

Not much... distance?
and I already got one.
(It's under the kitchen table.)

really

Got a honda vfr out there, and the harley is really took apart...

I just like bicycles.
They are an excellent means of transport, and the motor assist helps a lot!

Very inexpensive, a complete package universal application design... Gosh, what's NOT to like!

As far as using 'unusual' engines, Gosh!!!! What a challenge!
To resurrect something that was otherwise headed for the foundry, and create some bit of entertaining transportation with it... Wonderful!

Welcome aboard Motorbicycling.com !
We do a LOT of fun stuff here.

Best
rc

a PROUD member of the 20mph Club!

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