[spectastic]

I'm considering getting a pos mtb and motorize it for off road and touring uses, using one of the 80cc kits that costs ~$150 on ebay. Anyone done this? I've got some questions..

legal:
one of the major reasons for doing this is because I don't have to pay for registration and insurance on it, or at least I hope so. TX law states that it needs to meet 3 standards (<50cc, <30 mph top speed, automatic transmission).. But I'd like to think even if it's 80cc, it shouldn't be a big deal, right? I mean it's not like I'm going to be pulling wheelies with this thing. I can't imagine being pulled over and having to prove it meets state regulations..

maintenance:
I imagine the thing should be pretty straight forward right? carburetor and spark plugs should be the main things right? single cylinder should be pretty reliable.

saw some youtube videos on these 80cc engines. thing sounds like a tractor, even with the muffler. any way to address this?

I assume there's no catalytic converter, with it being so cheap. any health concerns with that?

are wheel changes a huge PITA? or is it not really a common problem with mountain bikes? the thing weighs about 25 lbs, which isn't too bad. I can't imagine that would be too much of a problem for 2" or 2.5" knobbies. right?



I'm considering taking a motorcycle around the country. however, I find taking a bicycle much more attractive. But I also don't want to pedal up mountains and through the desert. And I don't want to buy a dirt bike that costs money... So motorized bike sounds like a perfect compromise..

 

[Unkle Krusty]

Thought of it.

They used to be popular, driving directly on to the back tyre.
Now the engine sits in the middle of the frame. The 80cc will likely do 50 to 60 mph. So I suggest disc brakes on the bicycle. I also heard it is best to use a rear wheel with 36 spokes. Let us know how it works out.

Unkle Crusty*

 

[Porky]

That under 50cc rule is normally strictly enforced at least by law.

These sub 50cc bikes are very popular in my town, especially right in the city.

You probably don't know this but motorized bicycles have been around forever:

https://en.wikipedia.org/w/index.php?search=Whizzer+(motorcycles)&title=Special:Search

Google motorized bicycles:wink:

Sam:coffeescreen:

 

[Dodsfall]

Unless it's clearly stamped on the engine somewhere, it's going to be hard for someone to determine at a glance if you have a 49 cc engine or an 80 cc engine. That being said, there may be a few people in law enforcement who are experts at telling the difference.

Unless you are making a nuisance of yourself, odds are you won't be checked. Be prepared to pay the fines if you get caught, or simply get a motorcycle license and you won't have to worry about that part.

 

[velisoped]

Saw these this weekend. Maybe you can get some ideas from it.

 

[Unkle Krusty]

Power to the peddle

Up here George of world record fame, builds 2 and 3 wheel units with an electric drive motor in the front hub. The seat and center frame of the three wheel units lean. Add shopping baskets, and they are a popular go to town unit.
Next time I see him, I will ask when he is going to put an engine in one.

I will share the abuse I get with you guys.

Unkle Crusty*