BMX build, would like some advice before I go about this...

intrepid

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I plan to motorize a bmx bike. Here is what i want.
quick
looks good
good power, good engine/kit
frame mounted
cheapish, i guess
everything BUT the abomination i built last year.(Big, heavy, tires one inch thick, pain to work on, chinese engine, big mess with doing anything, tires pop nearly every ride)

I havent posted for like months so hello everyone but since then i basically rode my piece of s**t for a bit until i got fed up with the tire pops. I sold it, and the guy popped the tire a few days after he got it which i feel bad for, though not my problem anymore i guess lol. I plan to do something better, easier, more fun
98735

Kink Gap. Found on cl for 200. If i dont get it I will get something close, with nice thick tires and some brand besides walmart with a retail price over 200, just a nice bike but used i prefer on price, the one i found is quite unused

QUESTION: How the hell do i fit an engine on this thing?
I thought a bit and came up with the following few ideas

1. Mount engine on the bottom of the frame, this sounds the hardest for me. I see a lot of indian guys on youtube doing this with cookie cutter frames, and cookie cutter engines. I don't trust this too much since they need a cookie cutter frame designed for a bottom mounted engine to even do it. Sounds hard to do it on anything else that way I'd think. If I found a way to do it, I would love the look

2. Do this, somehow. https://motorbicycling.com/proxy.php?image=http%3A%2F%2Fimg.photobucket.com%2Falbums%2Fv641%2Ftumac%2Fenginemount002.jpg&hash=800683162ef306f6e1ba92b6614045eb I would like this the best and looks great though I can't find any words from anyone who has ever done this and seems like some hard custom work npot to mention an engine with that shape to find

3. I mount the engine as on any other bike with room for it, but instead of cutting and expanding the frame around the engine(which everyone else does and i think it looks TERRIBLE) I will split the top bar horizantally and turn it to two bars wrapping around the cylinder head and finishing back together just where the top bar should end normally, at the foot of the seatpost. This sounds most easy to me since its just cutting, bending. If i do this I plan on using a yd100.

If I use idea 1 or 2, would anyone know what kind of engine I need that would fit that way and work? Thank you for reading all this
If anything comes to mind, please tell me. Come up with your idea and tell me it, or if you like one of mine tell me why!
 
Option two using an eBay pocket bike engine.

The other two options are back AF.
98739
 
What did you want to use this bike for?
Are you intending it to be road legal transport?
Are you intending it to be a freestyle bike for the skatepark/ dirtjump trails?
Is it important for you to be able to pedal power the bicycle with no help from the engine?
How far are you going to have to pedal the bike without help from the engine?
Good luck with your project. Stay safe, and fit good brakes. 🙏😅
 
What did you want to use this bike for?
Are you intending it to be road legal transport?
Are you intending it to be a freestyle bike for the skatepark/ dirtjump trails?
Is it important for you to be able to pedal power the bicycle with no help from the engine?
How far are you going to have to pedal the bike without help from the engine?
Good luck with your project. Stay safe, and fit good brakes. 🙏😅
I'm a rising junior now in hs and hope to build one in time for college to get around campus, though its all a little idea and I shouldn't worry about that so soon. If I were to build the thing today, I would ride it around town and screw around. I have 2 friends with mopeds go about 30-40 and I'd like to be able to keep up with them.

I don't care at all about legality. I rode by cops going 30 on my last motorbike all I did that was precautionary was turn the engine off. I won't worry about legality since the cops around here dont seem to care or even know what the hell I'm riding.

I love doing jumps of bmx bikes and wheelies, so yeah. I also look forward to trailing on it. I dont think I will do anything crazy like go to the skatepark with it or jump down flights of stairs, but I would like some maneuverability and jumpiness on it, so yes.

After I fit the engine on a bike like this I will not want to ride it without the help of the engine. I don't think its too important

I would imagine that I will only want to pedal the bike as far as it needs to start the engine. Another thing coming to mind is through a stop light that just turned green and I gotta go quick and dont have time to start the engine and go, but I wont be doing this for far I don't think.
 
The triangle frame is fairly important,,, I my self would not remove the the bottom angle post...

A fellow on this forum did a top post split tube so the jug and head fit between it,,, of course he used a 2 stroke engine on his build
View attachment 98740

Pick up some used bikes for the tubing,,, get your welder friend with the jigs too tack it together so its alined and straight... 👍

Run the tubes the full length from the steering head too the rear wheel flanges was my plan on a fat tire bike project,,, I got lucky and didn't have too split the top tube too fit the engine...

Make sure you leave enough room in the frame for different engines,,, that way your not bogged down too 1 style or brand 😁👍

Future up grades that is,,, try too use add on engine mounts,,, that way they can be replaced latter if you have too do a engine swap out...

Im only throwing out ideas as its interesting too look at a few options,,, focus on the main build,,, with options to change things up later on down the road...

If at all possible,,, your not going too have alot of real-estate too work with,,, you'll have your work cut out for you...

Anything is possible if you have the time and a few funds...

Good luck,,, keep us up todate on how this transpires 👍👍👍

All builds put us the challage...

Don
Cool, yeah that sounds like a good idea
 
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