What engine for a go kart?

[ubersoldat]

Hi, I've read some threads at this site and various other info about karts, and I'm actually new to go karts I'd like to know what kind of engine would you prefer. I would like to put ~6hp gas engine. I'm planing to build my own kart and I can't decide what engine to buy (well this is the most expensive part of the kart).
Here is what I've found:
http://www.duropower.com/item.asp?PID=9&FID=3&level=1
http://www.duropower.com/item.asp?PID=10&FID=3&level=1
http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=96549

I believe these are most common.
If you have any other suggestions please share.

And what is better a 4stroke or a 2stroke engine and why?
I'd also like to know if it is better to buy a low power engine but also put a TC on? Or just a powerful engine with a clutch?
Thank you for your answers I appreciate your concern.

 

[sayre315]

well on the engine thing i'd say get the harbor frieght,
if you want to spend less than check craigslist for tillers, edgers, chippers, engines ect.
you could find a briggs 5hp for a very decent price
you could easily get one for under $50
and i'd say if you want to spend the money on the tc then do it
but a 5hp engine would do fine

 

[kibble]

4 Stroke engines are easier to use for the most part and are easier to get, but 2 strokes have higher RPM usually and require mixing oil with gas. It all depends on what you want to do. If you're pretty new to this stuff, you may want to stick with a 4.

All the engines you posted are Honda Clones and are pretty much built the same. They're really good for the price, a genuine Honda of the same power would probably run you $400+.

Using a TC will give you more get up and go power as well as a good top speed and are definitely good if you're planning on doing a little bit of off-roading. Using a clutch, if geared properly, will work well too, but at a trade off of power vs top speed.

 

[modelengineer]

What engine for a go kart?

Motorbike engine for fastest, best acceleration, best noise, most fun. Industrial engine for (sometimes) a cheaper alternative, and is easier to set up.

 

[Russ2251]

what is better a 4stroke or a 2stroke engine and why?

I admit that I am a 2 cycle chauvinist.
Reasons are many:
Lighter.
Faster.
Far less complex (only 3 moving parts).
Power to weight ratio is roughly double that of an equivalently sized 4 cycle.
No oil changes required.
Down side:
Somewhat noisy.
If not 'in tune' can be smokey.
Some folks have a problem with mixing oil and gas (known as Kool-Aid-aphobic).
Seems to me (for the most part) that those who don't like them have never used them, or even understand them.

 

[ubersoldat]

Thank you for your answers. I also wanted to ask you where do you live, and does harborfreight deliver engines to your country and if not do you know any e-shop from which I could buy an engine and get it to my country (European Union)?

 

[modelengineer]

Ubersoldat, shop around your area to find places that sell similar engines. It might end up cheaper since you don't have to pay for delivery from the states.

Russ, you forgot that 2-strokes are noisy, vibrate more, pollute more (not a big deal IMO) and use more fuel.
Don't get me wrong, I love 2 strokes but in many applications 4 strokes are superior.

i.e for my buggy; people who have used 2-strokes (CR500) have seen fatigue cracks in the engine mounts and all over the chassis because of the excessive vibration produced.

I chose a 4 stroke engine because of the extra low end torque, less vibration, less fuel consumption, dont need to mix fuel (not a real problem, I agree, but better if it can be avoided), more pleasing noise (completely subjective), larger selection of suitable engines in the 500-650cc range... the list goes on.

 

[Russ2251]

I forgot nothing. I could easily fill pages with advantages/disadvantages.

you forgot that 2-strokes are noisy

I said that.

vibrate more

Because they fire more often, silly.

pollute more

Said that too.

use more fuel

Non issue with a kart. What's the importance of milage?
Does Jr look for mileage? Unlikely.

 

[Kenny_McCormic]

They are so light they sip gas no matter what.

 

[jr dragster T]

Yeah realy this is a FUN KART group not a anti-polution site. If your having fun who's looking for milage. PS your talking to the guy who's engine burns 1.5 litre's of alky in 30 seconds!

 

[modelengineer]

Sorry, didn't read your entire post before commenting Russ. I believe you when you say you know lots about 2 strokes and 4 strokes having read many of your posts.

Because they fire more often, silly.

Yes, but knowing the cause doesn't stop them vibrating.

not a anti-polution site.

I know, it's one of the things that makes this site great! Youtube comments section I think is the worst for this sort of thing. You only have to post a video of an engine with the slightest whiff of smoke coming from it and if the GREENIES see it, heaven help you.

Anyway, I think ubersoldat now has a thorough understanding of the pro's and con's of both 2-strokes and 4-strokes and can now make an informed decision about which engine type to use.

 

[Russ2251]

...you say you know all about 2 strokes and 4 strokes...

I never said that, as it isn't so.

 

[sayre315]

well for some reason im not realy good with 2 strokes
i mean, there great and mixing gas and oil takes 15 sec's when you put the gas in there
but its mostly bc im not very familier with 'em

 

[Russ2251]

well for some reason im not realy good with 2 strokes...
but its mostly bc im not very familier with 'em

Get one and play with it. Take it apart...put it back together.
Once you study it and figure out exactly whats going on inside, it will suddenly all make sense. You'll be amazed at how simple they really are.
No poppet valves, camshaft, tappets, or gears. Timing is never an issue as there is nothing to time. Most difficult thing to understand is intake porting. These 2 dimensional animations don't help very much in that respect.
2 cycle animation #1
2 cycle animation #2
2 cycle video

 

[jr dragster T]

Timing is never an issue as there is nothing to time

What about ignition timing?

 

[Russ2251]

What about ignition timing?

Uses a flywheel key. You know this.

 

[Jerryburger]

I think the only disadvantage of 2-strokes for our use is unfamiliarity. Hardly ANY junk 2 stroke utility motors to pull off of the neighbor's broken edger and use for our "crazy ideas"......
If these things were as common as the flattys, it'd all be different. Most 2 strokes familiar to common folks are of the junky, tiny, tempermental weed-whacker variety. (No wonder the bias against them!) As it sits, to use a 2-stroke you gotta improvise and fabricate.... (Well worth the effort). Most of us don't (or didn't) have the means to do so. As far as vibration goes, I think that's mostly opinion. Maybe it's the higher frequency of vibration that bothers people more, but I have a hard time believing a 2 stoke literally vibrates more.

 

[ubersoldat]

Hello,
thank you for your answers, opinion. As I have a problem of shipping an engine, I went to ebay and craiglist but there you also have to meet in person because most people want to be payed in cash and they don't want to hear anything about shipping. So I thought maybe I could get the same engine out of a portabe power(electric) station.
http://www.duropower.com/item.asp?PID=172&FID=2&level=1

Can you comment upon this idea. I understand that the same engine cost twice as much as it did alone. But is the engine proper to be used for a go kart?

 

[Jerryburger]

The generator motors MIGHT have a goofy tapered shaft, which would make your life tough also.
I would think these guys might be able to ship international?
http://www.smallenginewarehouse.com/

 

[Kenny_McCormic]

Hello,
thank you for your answers, opinion. As I have a problem of shipping an engine, I went to ebay and craiglist but there you also have to meet in person because most people want to be payed in cash and they don't want to hear anything about shipping. So I thought maybe I could get the same engine out of a portabe power(electric) station.
http://www.duropower.com/item.asp?PID=172&FID=2&level=1

Can you comment upon this idea. I understand that the same engine cost twice as much as it did alone. But is the engine proper to be used for a go kart?

Buy a blue motor off the harbor freight website? http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=96549