Super Reliable 2 stroke, Max RPM 12K, 40MPH

  • Thread starter Deleted Member 4613
  • Start date
This is good it can bolt up to the 5:1 gearbox. However check out these ststs:

Total Displacement: 41.5cc
Bore: 40 mm
Stroke: 33 mm
Piston Rings: 2
Compression: 7.5
Carburetor: Walbro WYK-93
Oil Mixture: 40:1
Horsepower: 1.97 hp at 7500 rpm
Torque: 1.66 lb ft at 5500 rpm
Clutch Diameter: 78 mm
Spark Plug: NGK BM7A
Approx Idle RPM: 2500 rpm
Approx Max RPM: 12000
Weight: 6.5 lbs (2.96kg)

Although it can go up to 12k rpm it should never be pushed to that. That's 12k under no load or long duration. It has a max hp of 1.97 at 7500 rpm; once you go over that hp will begin to diminish under load. After you get beyond max hp the contributing factors to speed then become aerodynamics, weight reduction, gravity, terrain surface and wind direction. Still I do like this engine.
People use these on go peds They'll run under a four hundred pound load for years
Bwahahahaha, 2 strokers fighting over scraps. Us 4 strokers are riding, see ya!
Zenoah makes a lot of different sized small engines that are super reliable. The RC hobbies use Zenoahs, boats, planes, helis..

No reason to doubt the one in this thread for reliability. My only question would 41cc enough for a MB?
Everyone has an opinion...for me the 49cc CG engines are not enough on a bicycle without a fair amount of pedaling. I realize the Zenoah will come running much better than a stock CG 49cc but the torque to get up and go is very important to me. I would probably not be satisfied with a 41cc engine. For others it may be perfect.

The MB hobby has all sorts of chaps...some like to just fuel n ride, to others liking total build of bike n engine for performance.
I like the challenge of taking the CG engine in it's original...possibly crude...., state and building it to run better....tune...reinforce for reliability.

The challenge of refining the engine for performance is just as much fun for me as riding the bike.....building...tuning....

Some wouldn't want to fiddle with turning wrenches. The ride is where it's at for them. The unlimited options make this hobby great. So this Zenoah may be great for some. As for the seems very fair to me.
I have zero problems with motors like this for the average person.

The appeal of the cheap engines falls into 2 categories of people.
1. Limited income.
2. Weirdos/Tinkerers (me)

The mechanics and techniques involved in making a reliable motor are actually quite simple. The real challenge is just getting a quality engine from the start.
I think I fall into categories 1 & 2.
I’d possibly be classified as a broke, weirdo, tinkering gear head.
It’s just not typical for a 64 Y/O to be building and riding motorized bicycles. All the people I know my age who ride cycles either ride bicycles or BIG motorcycles…not the kind of cycles we ride on this forum.
I didn’t think much of this hobby until I got in to it. Then I got hooked.
I started by helping someone else to get their MB road worthy and reliable.
This hobby is unusually fun. The small size and weight of the MB makes it a blast to ride.
I think I fall into categories 1 & 2.
I’d possibly be classified as a broke, weirdo, tinkering gear head.
It probably describes a good number of people here, and there is nothing wrong with that. This forum is such a great resource for people to learn and research. If they take the time to study they can plan out a reliable bike build while also keeping the costs down. I laid out a build using the Hyper cruiser with upgraded wheels and disc brakes with the silver slant engine kit from BE and it ended up right around $500, and that was with a couple of personal additions