I'm starting my first engine driven builds. So fast I've taken a bike and key jumped right in. I've gone over handlebars going 10 miles an hour before and walked away, but now, it's getting serious. I have an older 3.5HP Briggs and Stratton and a nice heavy bmx frame grime the 90's I'm trying to build around. The lower bar is actually off an electric moped my boss found in the garbage. It has a perfect place to mount the engine and everything. I have front mountain bike suspension I'm putting on it and it is definitely getting a sweet of moped rims and brakes. So I guess my first question is, are 17 inch rims the biggest I'm going to find? I want the latest tires I can fit on the frame. I have been looking all over eBay and that's the largest rims I've seen. Two, I have front suspension, but I am going to build a seat on springs. Is that going to be enough to make it a comfortable ride? I want to RIDE ride this. What are some good designs for spring loaded seats? I've seen a few different styles. Which ones are the best? Next is building the tank. The motor is older and is choked not primed. When I build the tank for it, can I put a primer on it? As of now I need ether to get it started and I would prefer a sealed system. It would be left outside a lot. Don't need to be getting water in the gas. So I was just given one of those tire driven generators for a bicycle headlight. Has anyone hooked one of those up to their motor to put power to the headlight, brake light and directionals? Am I going to burn it up? It's older than I am so it's quality but I don't want to ruin it. I've been doing my research but I am not finding any definate answers on this stuff. Or maybe I'm just wording it wrong on trusty google. Also, what size sprocket should I get on the centrifugal clutch and rear tire? I know these are a lot of questions and this isn't the right forum for asking questions but I wanted the motor guys to see this. I want to do this right the first time. I'm building this to ride. I know I have a lot of questions, some of which are probably obvious, but at least I'm asking. This bike is getting built in my down time at work and I really need to streamline this build. I would love to ride it before the winter... any help would be great! Thank you and I apologize for the fact that this isn't the place for this.
need some advice. just a few questions before I start my bu
- Thread starter mobilrods
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so heres a few pics to make this a legit build post... i have more than this going on right now...
The heart
The skeleton
So I guess its newer than the 90's.. but it is seriously heavy. Its a good strong frame. I wish i had taken a picture of that moped frame before i cut it up but i jumped in on a whim and a happy with what i saw. It's gonna be nice and low and it is some nice thick pipe so i will have some strength. it also going to stretch it a good 6 inches. i'll put some more pics up when i get a chance.
The heart
The skeleton
So I guess its newer than the 90's.. but it is seriously heavy. Its a good strong frame. I wish i had taken a picture of that moped frame before i cut it up but i jumped in on a whim and a happy with what i saw. It's gonna be nice and low and it is some nice thick pipe so i will have some strength. it also going to stretch it a good 6 inches. i'll put some more pics up when i get a chance.
That looks like a good engine to start with but you are going to have to do a lot of modifications to fit it in that frame. Moped wheels are constructed the same as motorcycle rims so you can easily lace a moped hub into a motorcycle rim. That's what I'm doing for my rear wheel on my build. That way you can get larger rims and tires, I'm using 21" mx rims that with tires mounted come out to 28" diameter. Also the bicycle generator probably won't last more than a few minutes running off of the engine, you can get a small generator from kubota tractors that works great and already has a belt pulley you can run off of a jack shaft. Look for my thread "another btr build" and rollinlow's thread in this section for ideas.
So I guess if your 21 inch rims end up being 28 with tires then 17s might be just fine on my 20in frame... I checked out those generators from kubota. They seem to be reasonable priced. Thanks for that. That'll probably be the route I take. The bottom bar I'm putting on it drops down pretty low. With that and bowing the top bar out there should be plenty of room. I'll try to post a picture or two more later so you can see what I mean.
