Are 2-Stroke Bicycle Engine Kits worth it? Let’s find out!

Are 2-Stroke Bicycle Engine Kits worth it? Let’s find out!

So over the past few months I’ve had hundreds requests to do testing on two-stroke engines Now I’ve got about eight or nine two-stroke engines whether they’re weed trimmers or snow blowers I have all sorts of two-stroke engines, but I really wanted to do something different So I went out and found a two-stroke bicycle build a bicycle kit for a pretty good price online Now the price is probably indicative of the quality. It was only I like $120 so I don’t think this kits very good But if it needs a little modification to make it work, I think we’re up to the task So anyway, let’s go and get this project underway and put together this bicycle and just see how it does. All right, let’s see What’s in this bicycle kit? First step I’m going to make is to go ahead and remove the rear wheel and install the sprocket Sure looks a lot like a recycle tire. These little rubber scraps are not quite consistent So it’s very important that I get this sprocket centered up perfectly and unfortunately It’s going to be pretty hard to do unless I shim it up with something so what I’m going to do temporarily is use some zip ties to stick between the sprocket and The axle itself the hub itself and that’s gonna help me shim it up and make sure that everything is spaced. Just right These bolts are not that tight So now I’m going to ahead and tighten them down a little bit more and when tightening these bolts it’s important to do it incrementally Just like you would any part that Has a lot of flex in it House you can see I’ve got the sprocket installed the space between the hub and the sprocket is even all the way around it did Not have a very tight fitting and that’s why I use those zip ties so what I’m going to do now just spin this wheel over just to make sure that the sprocket is Balanced and that’s also fairly straight Okay, that’s pretty good that’ll work really well So before I put this engine I’m really curious Regarding what the inside this engine looks like and I’m also curious about how much torque is applied to these head bolts So I’ve got a little torque adapter hooked up to my wrench I’m go ahead and take this Sutter head off and then take a look inside Okay, that was torque to 9.2 foot-pounds of torque 11.9 k-8 point five and seven point three Okay, all that sara is an aluminum gasket there’s an oily coating inside on the cylinder Okay, it looks like the back bike mount will work but the front bike mount is too narrow Then this kit came with it looks like another Universal and my adapter So I’m go ahead and swap these two bolts out and put the other adapter on This is definitely not the way to do this if you want to keep these bolts But I don’t plan to ever use these again. I just need to get them out I’m gonna remove the rubber handle grips. These things can be difficult to work with rather than getting these all oily I’m just gonna use compressed air and a nozzle. I learned this trick many years ago Okay, this is the clutch assembly so I’m going to do is just connect this cable to the clutch assembly This little spring here is nothing looks like nothing more than just a heat shield spring so it slides right over the cable keeps it from touching the exhaust and melting and There’s a little bracket here in the back that this cable will slide through So what I’m gonna do now is just put this little spring in place Slide through the clutch assembly There’s a little piece that will allow this cable to stay in place Now the gear should spin freely and it does So next time I hung up the throttle cable, so what I have to do There’s a little dowel that needs to fit into this handlebar. It’s a quarter inch. So what I’m going to do is just mark my Handlebar where I need to drill a hole and then tap a quarter inch hole So anytime I have to drill a hole in something that’s round I like to use a center puss just to sort of create a little Indention that allows a drill bit to stay in the right place while I’m drilling Okay, now we’re going to go ahead and put the throttle cable inside the carburetor If you look inside the carburetor you can see the carburetor is cooperating and working correctly Okay, imma go ahead and install the coil So the gas tasting arrests right on top of these cables and that’s going to be a problem because I won’t be able to use my brake So what I’ve done is I’ve split a piece of PVC pipe which is going to overlay these Cables and when I clamp the tap they tank down. I’ll still have freedom of movement for these cables So I want to install the chain guard I think chain guards are pretty important, especially when the chain is this high up because loose clothing could get caught in it So the front of this is supposed to attach near the front sprocket in the back is supposed to be zip tied Around this frame and as you can see, that’s just not going to work It’s going to come in contact with the chain. At least it is at the bottom as well as it’s all contorted So what I’m going to do is I’m going to just cut a little bit of metal out So it’ll fit nice and tight up against the frame and I’ll poke a couple holes in this and zip tie it together So it’ll have a nice secure fit One thing I want to point out is this fuel tank came with a pretty good sized dent This dent is larger than the diameter of my finger and it came that way I guess damage and shipping not a big deal because I’m just gonna use this bicycle in this engine for the video test But for something that’s really concerned about how their product looks this may be an issue So just a quick rundown on how this is supposed to work Obviously the engines gonna have a choke. So if you want to start this bike what you do is wheeze the clutch lever it disengages the engine so the chain going to the engine spins freely and There’s a little button that you can push in that keeps the clutch from being engaged Because the minute that clutch engages the engine the engines gonna want to spin over So, how do you start this bike? You want to get pedaling get a good speed up? Let the clutch out it’s gonna spin the engine over in its start there’s a stop engine switch on the near the Accelerator so you can just push the clutch in shut the engine off keep riding or you can just you know Use the shut off switch when you’re near a stop So what next up some fuel this requires an 18 to one mix during break-in period which is several tanks of fuel That’s really surprised. This thing is probably gonna smoke quite a bit Well that two-stroke bike build was a lot of fun but riding the bike was even more fun That is quite a nice little kit. I was really impressed with it how well it went together Well, I didn’t find instructions for it in the box. I did find some online It is a universal kit requires a little bit of modification But not too hard to put together Also the bike seems to run comfortably between 22 and 25 miles per hour much more than that And it seems to vibrate a lot the engines just not very refined. It tends to really shake quite a bit I was really surprised at how much it does shake but 22 to 25 miles per hour is a lot faster than I can Pedal on a continuous basis. So it’s a big improvement over just riding using my own power Anyway, just want to say thanks to those that recommended. I start testing with two-stroke engines I plan to begin testing with two strokes really soon Thanks so much for watching the video. Please take care, and I look forward to see you next time

About the Author: Michael Flood


  1. Loved the video, also saw the four cycle kit, but I’m going for the two cycle, expecting mine in a few weeks

  2. I had 4 in the past years ago motorized bikes these Engines and kits dont last to long it's best to just buy a Real moped are 50 cc scooter Also the kits messes up your Back Rims and Bend them Because of the motor Bicycles was not meant to have Engines and go high speeds

  3. Bought one of these kits years ago, was made in China then sent to Japan for new bearings, was sold from California vendor. I put over 25k miles on this little kit, only changed a few tubes. Good times, bought and built one with my dad before he passed away, many miles of smiles from dad.

  4. Apparently some <cough>CENSORED<cough> believe they should swim against the stream and instead of electrifying their bikes, or replace their mopeds with e-bikes they purchase 2-stroke bike conversion kits. YES 2-STROKE! I kid you not. It's as if science stood still the last 50 years. Goddamn. There truly is no end to human stupidity!! (And let's not even mention safety here).

  5. So what is the best two stroke bicycle motor out there on the market right now then? I've had a few but they all seem to wear out prematurely. I use Maxim 927 pro series 2 stroke oil.

  6. for one your first mistake was buying a cheap engine. If you want a quality bike you have to buy a real beach cruiser bicycle with a well welded frame. if it is not welded to your liking then touch it up, with a weld of your own.[ reinforcement] then buy a real engine that has been properly machined. then it takes a lot of time and money to find the right parts, to make a good bike. you first must make sure the frame can take the horse power the engine has to offer. did that ! now you must match the engine to the frame with a real motor mount system. i will let you figure that out as it took me a long time and money to get there.[vibration]. HINT when you see something on e-bay or amazon buy it now, you may never see it again. bike in place and motor properly mounted, we move on to exhaust. the u pipe in the exhaust must be properly fit by opening the inside dimensions of the pipe by spreading the ID, figure it out bro. [ mechanical skills required ] by the way im using voo – doo exhaust that has been bored out. with expansion chamber. now you focus on intake system. the average carb. is 19mm. but if you want real power then i say run with shit that puts that in the dust with a 21mm. carb. or better yet a 28mm plated. then you add a reed valve kit and tap into that with a v- valve that supplies a air boost kit and a nitro kit. i also suggest a 1.5 gallon gas tank. or you may have to fill gas more then you would like.

  7. Great review!
    I appreciate you showing the dent, but I laughed to myself thinking about a hypothetical super-anal person who ordered a two stroke bike engine from China and was surprised and pissed that there was a dent in a thin-walled tank. 🙂

  8. I bought a bike with an 80 cc kit already installed. I've ridden maybe 100 miles on it (so it probably has 450 miles total on the engine)…have enjoyed it a lot…but yesterday…I tried to take it out…..
    started peddling to start it….it was starting….but then suddenly stopped in it's place…. locked up and I flew off head first….I was lucky to have not hurt myself worse than I did.
    Can anybody tell me ….why it locked up….I have the correct oil to gas mixture….
    i mean it's totally locked up….I can't even turn the back wheel….or pedal it….it's locked….
    What can/should I do? ……and I'm not a mechanic….but I will try to fix it …if someone tells me what I should do…
    please help….

  9. I started to get really get diapointed by my 2 stroke kit back then because of its constant break downs, cost of fuel, and leaving me stranded in the middle of nowwhere. I got a kit hoping i can beat the cost of public transportion because it started cost just as much as operating a motorcycle but definitely not worth the headache of running maintenance.

  10. Thanks for the info I'm buying one from a friend of mine. Never rode one before but after watching your clip I'm excited and well informed thanks

  11. Well , you checked head bolt torque when you removed the head but WHAT IS THE HEAD BOLT TORQUE SPEC SUPPOSED TO BE ?

  12. I built my own with an old Tanaka Bike Bug 49cc bike engine kit and got it a consistent 38mph, only problem was spokes coming loose and then bent rims. Went to a dual wall rim with stainless steel spokes with some Loktite on threads and that fixed it. The drive was a cog that was friction driven, the engine was on a spring loaded pivot and started when engaged to rubber. I had guys chase me down to talk about it, so fun. I sectioned a RM250 expansion chamber and it got a CrAzY powerful powerband that would kick in at around 15mph, really screamed ?

  13. I buy DF RTX 49.7cc it a clone honda cub c90 and having trouble riding it because i wear knee brace! I want know there way start ride this scooter because can`t move foot pegs up & i stand 6' 1" tall my doctor want start riding bikes.

  14. can these go up hills fine? i plan messing around on one of these on my street and there is a big ish hill that i would need to get up. also if im not worried about noise do i need the exhaust? i hear the ones with these are really restrictive and that its good to either remove the baffle or to just cut it back a bit but why couldnt i just not use the exhaust at all?

  15. You should get a high performance engine with Reed valve intake and high performance carb and head with expansion chamber exhaust and see how fast that goes… anyways I love the videos I've watched allot of them keep up the good work

  16. Here's a tip. Wrap some innertube rubber around frame where the engine mounts to frame,double up the nuts so it will stay tight.Helps cut down the vibration.

  17. Who the heck dislikes your vids? I personally think they are amazing. My dad always distrusted brand name hoop la, and you break it down into controlled testing. Much love

  18. I bought one of these a few months ago from BikeBerry, put it on an aluminum frame mountain bike. Carbeurator kept leaking, had the bright idea to raise the motor up and use the rubber kit that's for that purpose. Bad idea, vibrations make it nearly undriveable, and eventually one of the connector bolts snapped off rendering it not completely safe to reinstall and operate. Solved the brake problem with a dual brake lever, but the rim brakes quickly wore down to nothing. Going to buy a steel frame mongoose with disk brakes and a slightly more expensive engine. I am NOT mechanically inclined but it was easy enough to install and maintain for awhile.

  19. I would recommend building one of these to anyone. I built one that I have had for around 2 and a half years. The only things of consequence that broke early on were the actual throttle ( the fake chrome end ones)and the stock CDI. I've had the usual punctures and cables break (I now carry a spare inner tube and a cable, but shoelaces have got me home). The number one thing that causes breakdowns is the spark plug. I recommend carrying a spare and a scrap of sandpaper. Before I even put the kit together I got a proper sparkplug cap/boot and a decent sparkplug. The plug makes a lot of difference. It takes very few tools to work on these engines and they are extremely basic and easy to work on.

  20. Same kit I had on my bike, it took me everywhere! To work, friends, and it was fun in mud too ?, until someone stole it?.

  21. I like you carisma very nice ,you help a lot of people don’t have car and they have to walk or take a bus and that is a pain in the ass good job bro

  22. I had fun putting mine together too. Mine didn't come with a frame adapter, so I made one. Also, I put the engine on a bike with coaster brakes, which worked out just fine. Very fun, and more powerful than expected.

  23. These kits are great if you are handy but if you cannot adjust and repair yourself its just not worth it, because they are in constant need of repair and adjustment.

  24. Im turning 16 in like 10 days an this is going to be my Vehicle of Choice. I don't want to get my drivers licence because that takes having a car and needing to pay insurance on it. I also live in florida so I'm not totally sure if these are legal for me.
    Also the bike im using is a combination of 2 roadmasters that my dad and me found, it's going to be an amazing project.
    And thanks for this great review on this video and that 4 stroke video.

  25. I know this is an older vid/ I have seen it before. Could/should have double nutted that motor mount bolt to remove it without damage.Just one idea, IF you have 2 of the correct size nuts which should have come with the kit…

  26. Seems governments all around the world are all becoming tyrannical. One cannot travel freely with all of the pesky law's these days.

  27. I also bought this – it is great. however, I have one issue with carb. the float is taking in gasoline, so it just floods the whole engine with gas. I think a replacement float is not very feasible – might have to make one myself..

    any others with the same float issue out there?

  28. That was awesome, I was just looking for these motors, I just wanted a cheap motor that I can use for rc, think this would be awesome lol

  29. You have to love anyone that will take off the head just to look inside and note the torque/ lbs. needed for each of the four bolts caps. This person reeks devotion and would highly recommend him working for Consumer Reports. I believe they would beg to have you; your Resume would be your You Tube site / links and TYVM.

  30. In case no one has mentioned it already break away torque is in no way equivalent to tightening torque. The torque on those head bolts would be I’m guessing between twenty six foot pounds and forty foot pounds depending on what they screw into.
    The tensioner would be better fitted to the top brace and pulling on the chain instead of the bottom pushing on it, safer too as it won’t slip and jam the wheel.

  31. Why is a 2 stroke engine are less durable than a 4 stroke engine? Is it because they have less lubrication than a 4 stroke engine?

  32. See. Buy Car. $500- $900. Then im Brooke all month.
    Next licence DMV. $52. TABS. ? $130. Insurance..$200. ? Why not? $200.. It's so screwed anyway..
    Should I fill the Tank. Always broke anyway.$70.

  33. I've been building and riding these things for years. For those interested, there are better adapters for the rear sprocket. The standard rag joint setup sucks and will end up damaging your spokes. I personally use the Manic Mechanic adapter that bolts around the hub.

    The frame I use is square tubing, so the standard idler/guide pulley stays put, but because of the stress of the chain, on round frames it is prone to being pulled into the rear wheel to eat some spokes and bring you to a halt. Get one that bolts to the bottom and upper arms on the back of your bike.
    Some people ride for speed. Take the bike fenders off if you do. Vibrations will weaken the mounting points, particularly on the front fender, and well, one of these lodging against the wheel is gonna be a bad time.

  34. I had to do some MAD fabrication to mount one of these to a tricycle. I had to get a chunk of metal made that allowed that sprocket to mount to one of the rear axels at the middle. Had to cut away at a shield in order for the sprocket to fit. Had to eliminate the ability to use the pedals for anything more than a foot rest because the trike mechanism for the wheels to spin freely and change gears could not be salvaged in this build. Because of that, I had to buy a pull-string kit that bolts right up to the motor in order to get the thing started. At the end of the day, it works! Now my biggest challenge is finding a way to mount the drive wheel onto the axel in a way that it can withstand the torque the motor produces.

  35. Just so you know, You cannot ride a bicycle equipped with an ICE of any size on British public roads. It can of course be ridden on private roads or private off road with the land owners consent. I don't know when it was outlawed because I can remember seeing them when I was a boy in the 50's/60's.

  36. I was just thinking when I was riding my bike. It would be cool to put electric motor and a two stroke motor on it.have a bike that's built for speed Max out the two stroke motor shut that off and turn on your electric motor and go faster that's what I imagined sounds cool right?

  37. Im a huge fan of Project Farm . just made a Exhaust that makes a 2 cycle as efficient as a 4cycle , it is very quiet, wayyy more power, .. My testing for a 52cc scoooter was 121 mpg in real world testing (was getting 80-ish?).. stop lights, slight hills, and playing with the full power at times. NOW 2 cycles can really compete with 4 cycle in all points. the power is amazing! all the way throughout the R.P.M. range ( it can lug like a diesel) to climb hills like it never could with a tuned exhaust… . unfortunatly I had to put in larger head bolts. it had too much power! 1.4 liter tank went 44.7 miles!

  38. I really enjoyed watching your video…more video uploads please…
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  39. I built a mini-bike with a centrifugal clutch a few years ago. I got a little over-zealous after I got the engine, drive and wheels installed (no brakes, yet but who needs em!). First run –thing fired right up – idle was set at like 2500 but how was I to know? Off she goes with me hanging on for dear life as I seemed to overlook the fact that a centrifugal clutch engages at pretty low RPM and doesn’t let go till you throttle down. Well… I can’t throttle down and no brakes of course! Got up to like 20 MPH in the back yard with no way to stop. I have like 30 trees in a 1 acre lot. After dodging trees, my house and the dog for like 2 minutes, I bailed and slid across the grass for like 10 feet. Wish I had a video – it was hilarious

  40. We have built 3 of these and they are ball !! .. they have worked great for us. We use the Walmart Nel Lusso Mens frame and they look like an old motorcycle from 1901. We have about 200 miles on them an so far no problems. We have had to retighten some fastener but nothing broken. We did add disc brakes to the front (hydraulic bike disc brake) since the extra weight and speed (about 25 mph) needs a little more than the coaster brake on the back. We found some nice looking sprung seats and made some decals on a vinyl sign cutter with gold vinyl for the tank to make it look kind of factory.

  41. Hi, found your video very helpful, I have enjoyed fitting but I had to use my skills to make the engine fit, I recommend to others not to rush this project and found giving the bike itself a sevice , greasing the wheel bearings excetra as you need a good base to start from, best regards Pete UK

  42. I have a 1940s kit from Sears and the engine is bullet proof I have no issues at all goes to show how they made quality back then

  43. Are they worth it? Ask the poor soul behind you who is forced to breathe the oil from that engine. I would love to see them all outlawed. Double for diesels. After a couple thousand miles the stench really nauseates you. Oh, and by the way, the carcinogenic fumes have been long well known to cause cancer. They have known this for decades.

  44. 80cc not enough you need at least 200cc 4stroke for a big boy bike and Euro scooter transmission to convert some tourqe into speed. Finally get proper lights because you a big boy .

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