2 Stroke Vs. 4 Stroke

[Alex Behan]

So I’ve been seeing a lot of back and forth between the people who prefer 2 Strokes over the 4 Strokes and vise versa, and I was wondering which is actually the best overall. And why is that the best? I’m new to all of this and I would like to make an informed decision before I spend the money. So I would really love you’ll guys’ help and expertise on this subject.
Thanks!
-Alex

 

[Greg58]

This question is like asking if a Ford is better than a Chevy or Dodge, everyone has their preference. I can't help with four strokes since I haven't owned a four stroke bicycle. I have owned several dirt bike of both types, in smaller cc engines 2-stroke is easy to install. The four stroke will require a little more work, members like VMB who has built many of both could help a lot more.

 

[Greg58]

Norm from Venice motor bikes has said before to shy away from the ebay clone kits, I think the transmissions have been the problem. If you have a question on fours he would be a good source of information.

 

[Venice Motor Bikes]

I personally think the 2-strokes are more fun, (not to mention faster, lighter, easier to install & less expensive)... The down side is that they're less reliable & you have to mix gas & oil together to fill the tank.

The 49cc 4-strokes are slower, heavier, harder to install, less powerful & more expensive... but the up side is that they last longer & you can simply pull into a gas station & fill the tank if you run out of gas.... also as mentioned by Greg is that the only 49cc transmission that I'll use is the 7G Ghost Racer by GasBike.net... It has a very reliable bely drive (without a freewheel)... All the others IMHO are junk.

The larger 4-strokes (like the 212cc) have tons of power, but they're very difficult to install (& keep maintained).

 

[zean]

If you are able to purchase (they are hard to find) and ride a well built 212cc motorized bicycle you will never be the same. You won’t be able to say, “I ain’t never had too much fun.”

 

[Tony01]

2-strokes for the track, 4-strokes for the streets.

 

[Alex Behan]

I personally think the 2-strokes are more fun, (not to mention faster, lighter, easier to install & less expensive)... The down side is that they're less reliable & you have to mix gas & oil together to fill the tank.

The 49cc 4-strokes are slower, heavier, harder to install, less powerful & more expensive... but the up side is that they last longer & you can simply pull into a gas station & fill the tank if you run out of gas.... also as mentioned by Greg is that the only 49cc transmission that I'll use is the 7G Ghost Racer by GasBike.net... It has a very reliable bely drive (without a freewheel)... All the others IMHO are junk.

The larger 4-strokes (like the 212cc) have tons of power, but they're very difficult to install (& keep maintained).

Why are the larger 4-Strokes harder to install and keep maintained?

 

[zean]

The larger 4 strokes, if I may partially answer your question, weigh almost 40 pounds. They are big. They shake, rattle and roll. Someone with a lot of experience has to weld and/or cnc metal parts then bolt them together to make a precise mounting system. Slightly modified they have a lot of power, so the entire drive train, clutch, brakes, suspension, steering, tires and wheels etc. should be checked close regularly. Thank you.

 

[Sidewinder Jerry]

I've had my Robin Subaru 35 which is a 33cc 4 stroke for 11 years now. It was very easy to install since it's a rear rack mount. I also run through a triple chainring shift kit; the reduction range is 66.79:1 to 16.25:1. This enables me to do with a small cc engine what most larger cc engines can do. I also use a reduction gear box instead of a reduction belt drive.

 

[Venice Motor Bikes]

Why are the larger 4-Strokes harder to install and keep maintained?

zean did a great job of answering this question for me!

 

[Alex Behan]

zean did a great job of answering this question for me!

Thanks for pointing it out. So I understand if you don’t know but why does a 4-Stroke rattle and move about more?

 

[Venice Motor Bikes]

Thanks for pointing it out. So I understand if you don’t know but why does a 4-Stroke rattle and move about more?

It was pretty much already said... The large 4-strokes are big, heavy powerful beasts... & all single cylinder engines are impossible (by design) to perfectly balance... & to add to the problem; all the available 'bolt on' engine mounts available are inadequate.

As zean said, 'it takes someone with welding & fabricating experience to make a proper mounting system for them'

 

[Alex Behan]

It was pretty much already said... The large 4-strokes are big, heavy powerful beasts... & all single cylinder engines are impossible (by design) to perfectly balance... & to add to the problem; all the available 'bolt on' engine mounts available are inadequate.

As zean said, 'it takes someone with welding & fabricating experience to make a proper mounting system for them'

Ah okay. Well thanks for the insight!

 

[rugger327]

I gave my son a 49cc kit from Bikeberry. It's a clunky kit, but installed as expected with no instructions included. We have had it running a few weeks and the exit shaft out of the dual chain transmission broke. That should be a hardened steel component. The engine can't provide enough torque to break it, but it did. It must be a pot metal shaft. I doubt that I'll even pursue warranty because I don't want more junk.

We'll probably just pull the trigger on a 7G Ghost Racer transmission like Venice Motor Bikes suggested.

 

[mapbike]

I gave my son a 49cc kit from Bikeberry. It's a clunky kit, but installed as expected with no instructions included. We have had it running a few weeks and the exit shaft out of the dual chain transmission broke. That should be a hardened steel component. The engine can't provide enough torque to break it, but it did. It must be a pot metal shaft. I doubt that I'll even pursue warranty because I don't want more junk.

We'll probably just pull the trigger on a 7G Ghost Racer transmission like Venice Motor Bikes suggested.

Ive never owned one of those 4 stroke kits, bit over the years Ive heard of many people not liking that double chain drive transmission and swapping to the belt drive setup.

I can't offer any advice or tips and teicks since Ive always done the 2 smokers on my bikes, But frome what I always heard the two transmission setups to go with on those engines are the type you mentioned or one that was called " easy motorbike " if I remember right. not sure if this one is atill being made of not, but their website is atill up.

Best wishes getting that bike lined out.

 

[curtisfox]

Map is right they have been troublesome for years, I have a new one I bought years ago, come with a crocked shaft threads, better is the belt drive one........Curt

 

[emma21]

I’ve had both, and I’ve ridden my whole life. We can say that both 2-stroke and 4-stroke engines require an air-fuel mixture to facilitate combustion and push a piston down. However, 2-stroke engines have simpler designs compared to 4-stroke ones; they don't have a timing chain, valves, or camshafts. So a 2-stroke dirt bike may be less easy to handle at increased speeds compared to a 4-stroke dirt bike.

 

[Greg58]

Welcome to the forum Emma, I have had both two and four stroke motorcycles too, but the difference with these bicycle kits is a lot. You can make a decent running/riding bike with a $90 kit when it’s a 2-stroke, not so with the cheap four stroke. You have to go with the high end kits with better transmissions, most of the knock off kits from Amazon or eBay fail quickly.

 

[Mossy]

Old 2 stroke and new 2 stroke... My 74 40hp Evenrude outboard motor has the same engine as a 75hp the difference is the exaust and another carburetor... My artic cat from 74 was the same deal... In the mid 80's they peaked... By the 90's there was pressure from the EPA to replace them with 4 stroke engines... Gas to diesel in the big boats... 2 stokes went from 20:1 premix to 50:1 for the EPA... The 4 stroke got better to replace the 2strokes with counter weights to smooth them out over head cams to be powerful as 2 stroke... While this is going on outdoor power equipment barely changed... EPA didn't effect them off road engines... Plus it's a harder sell for heavier less powerful hand held engines... These 2 stroke engines for bicycles are copy's of the 1940's design and the 4 stroke engines only just got over head valves... So it's not a comparison to today's on road or EPA engines... They still require the old gas ratios and carburetors and like time stood still... The big difference is in the wide pedals to clear the 4 stroke... The 2's are made to fit a bicycle with no modifications just bolt it on... Rear sprockets all you have to change... A 4 has gear reduction or CVT belt... A 4 has less RPM range but makes more torque than a 2... More custom fabrication etc... It really depends on how you ride... And you're fabrication skills... And also how much space you have to work on and store your bike... Long distance go with a 4 if it's short distance a 2 is going to be better... Not a lot of money skills and space a 2 stroke is going to be for u... You can start out with a 2T kit and switch to a 4T later but if you modified everything for a 4T it's going to be difficult to go back to a 2t setup... Another example is the 2 stroke Tecumseh engine... It's 2 stroke but everything is going to build like a 4 is configured... Or the shifter and friction drive engines 2 or 4 stroke are set up completely different than either of those type engines... The China Happy Time is my choice because it's the cheapest and easiest build and I don't have a long distance to go... It's more of an ongoing never ending art project than something I would ever depend on...