Anyone add a motor to a bicycle?

raggie33

*the raggedier*
Joined
Aug 11, 2003
Messages
11,851
What's the easiest cheapest way to go? To me all the 66 cc engines look the same every brand spears to be the same
 

scalpel_ninja

Enlightened
CPF Supporter
Joined
Sep 16, 2020
Messages
355
I’m not sure if it’s the cheapest site, but this is a source that’s been around for a while: https://www.bikeberry.com/

You’re right in that most two stroke engines are pretty much the same. Some are marketed to have more power due to the construction and carburetor setup. Kits usually come with an engine, throttle, gas tank, clutch handle, exhaust, drive chain, and bolt-on drive gear for the rear wheel.

Installation is pretty similar, however if your bike is not the usual “two triangle” frame, modifications and custom mounts might be needed. Three add-ons that made my bike and my friend’s bike immensely easier to maintain and safer are:

Adjustable rear axle tensioners. The usual chain tensioner (spring loaded wheel pushing on the drive chain) often was a point of failure for my friend’s bike. I opted to shorten my drive chain to be just right from engine to drive gear with little slack. These tensioners are simple eyelets that capture the rear axle and a bolt is welded to it; tightening it pulls the axle rearward and takes up slack in the drive chain.

Mag wheel for the rear. The sandwich hub adapter the the rear drive gear has a risk of spinning free and ripping all the rear spokes apart when under hard acceleration (ask me how I know). A “Mag” wheel is a one-piece wheel without thin spokes. The construction is pre-molded and threaded for the drive gear to bolt directly to it. Some models also allow for adding a disc brake (even safer).

Disc brakes. With the added power of a motor, traditional brakes that rub on the rim aren’t enough stopping power and the posts where the pads mount can flex due to the higher speeds. This makes the pads contact unevenly with the rim, further losing braking power. A disc brake setup can remedy this.

Other considerations: upgraded exhaust to make it quiet enough for certain neighborhoods, new engines need a break-in period, and local laws and emissions.
 
Last edited:

alpg88

Flashlight Enthusiast
Joined
Apr 19, 2005
Messages
4,075
I installed such motor on a bike when i was a kid, about 35-40 years ago, but i'm looking at modern gas engines, and they are still the same as they were back then, nothing really changed. I put it on a pretty heavy duty cruiser. it had no front brakes, only rear coaster brakes. i managed not to get killed, but front brakes would definitely improve safety. different exhaust would not make it quieter, i tried, i even tried a muffler from a car. the tone changed a bit, but it was still as noisy, the whole engine vibrates and makes noise, not just exhaust gases. Did not have any chain tensioners, i removed links until the chain was tight enough, never had it fall off, or any other issues. That is pretty much it, very simple straightforward install.
 

knucklegary

Flashlight Enthusiast
Joined
Feb 11, 2017
Messages
2,768
Location
White Sand Bch
I owned a second hand Monark, they were sold by Schwinn. It came with a 2 stroke (gutless) motor. That was back around 1963. Motor eventually burned up, and then I bought a Honda scooter 50cc powerhouse! Used it for a newspaper route, I was the fastest delivery boy in town.
 
Last edited:

raggie33

*the raggedier*
Joined
Aug 11, 2003
Messages
11,851
Nah a ebike cost more both bikes new from Walmart cost me like 159 for both. I see some gas engines for around 130
 

alpg88

Flashlight Enthusiast
Joined
Apr 19, 2005
Messages
4,075
yea, good ebike is 1000 dollars to build, at least, i'm building an ebike with a mid drive motor now, at minimum it is 1200 bucks for a kit with a battery. if you want good quality battery with LG, or Samsung cells 200-300 dollars more.
Gas engine kit is definitely cheaper by a lot.
 

raggie33

*the raggedier*
Joined
Aug 11, 2003
Messages
11,851
Whats crazy I think it would take a 1500 watt electric moter to be as strong as a 50 cc 2 stroke
 

alpg88

Flashlight Enthusiast
Joined
Apr 19, 2005
Messages
4,075
I can not compare side by side, since i do not have my gas bike for decades, but going just by memory, my 2000watts scooter is much more quicker than gas bike was. 50cc have very narrow powerband, electrics are way wider.
 

raggie33

*the raggedier*
Joined
Aug 11, 2003
Messages
11,851
True my 250 watt ebike was fun ? But it's small frame and 14 tires sucked
 

orbital

Flashlight Enthusiast
Joined
Feb 8, 2007
Messages
3,309
Location
WI
+

edit:

I just keep thinking of a used Honda Metropolitan or better yet Yamaha Zuma (50cc) 4-stroke

..wrong footwear for this women, but you get the idea
1664832653953.png
 
Last edited:

Monocrom

Flashaholic
Joined
Aug 27, 2006
Messages
17,103
Location
NYC
Won't lie, after seeing e-scooters and e-bikes spontaneously combusting; I'd rather have anything with a gasoline engine instead.
 

aznsx

Enlightened
Joined
Apr 24, 2015
Messages
669
Location
Phoenix, AZ USA
Won't lie, after seeing e-scooters and e-bikes spontaneously combusting; I'd rather have anything with a gasoline engine instead.

Given my career, I'm of course a very 'E-' kind of guy in general, but those old classic 'mopeds' from back in the day are certainly looking better and better to me.
 

alpg88

Flashlight Enthusiast
Joined
Apr 19, 2005
Messages
4,075
Won't lie, after seeing e-scooters and e-bikes spontaneously combusting; I'd rather have anything with a gasoline engine instead.
that was one of the reasons why i gave my scooter away., If god forbid battery catches on fire, it will be a disaster in my apartment. i wont even be able to throw it outside the window cuz it would not fit. E bike otoh has a removable battery, i'll be charging it right by an open window, where i can just dump it out, if anything, Gas motor unfortunately is not an option inside an apartment.
 

jtr1962

Flashaholic
Joined
Nov 22, 2003
Messages
6,742
Location
Flushing, NY
I installed such motor on a bike when i was a kid, about 35-40 years ago, but i'm looking at modern gas engines, and they are still the same as they were back then, nothing really changed. I put it on a pretty heavy duty cruiser. it had no front brakes, only rear coaster brakes. i managed not to get killed, but front brakes would definitely improve safety. different exhaust would not make it quieter, i tried, i even tried a muffler from a car. the tone changed a bit, but it was still as noisy, the whole engine vibrates and makes noise, not just exhaust gases. Did not have any chain tensioners, i removed links until the chain was tight enough, never had it fall off, or any other issues. That is pretty much it, very simple straightforward install.
I tried one of these around the same time. I think it was called the Bike Bug. After about a month I returned it. The speed was decent. I could get to about 27 mph. The drive system was awful. It used a metal roller which chewed up tires. After less than 100 miles the tire was worn out. The acceleration stunk. It was way too noisy. And refueling was a pain as it involved bringing a gas can to the nearest gas station. I think I also needed to add oil to the gas. One day one of my neighbors knocked my bike over. The engine started making weird noises and running erratically after that. That's when I sent it back. It seemed to annoy drivers as well. I had a few of them get in front of me, and slam on their brakes. Never had that happen before I put the motor on.

Electric is worlds better. "Refuel" at home. No maintenance. Plenty of torque off the line. My brother got an e-bike and loves it. I have yet to take the plunge. I'd definitely go with one using a LiFePO4 battery though. I don't want to play the burning/exploding battery lottery. I can't trust batteries made in China using the cheapest parts.
 

raggie33

*the raggedier*
Joined
Aug 11, 2003
Messages
11,851
I'm more stupid then I used to be this dang thing took me damn near 4 hours to buid?.but my frame was not idea have to mod it to get air filter on
 
Top