Why isnt karting moving towards 4 cycle instead of 2 cycle. Motorcycles / Snowmobiles / and other motorsports have done. Longer life / easier to tune / And easier for people without alot of knowledge of motors to use.. Some of these motor companies need to come up with bigger 4 cycle race motors for karting.. Then alot of the noise people complain about at tracks can be alot easier muffled.. And stay open..
We already discussed this far and wide. CIK-FIA even pushed for it 20 years ago which led to a bunch of engines to be created (Vampire, Biland, IDEngine etc)
4-strokes are :
- More complex in their architecture, so more complex to service
- Service times were not so much longer than 2-stroke
- Un-fun engine (doesnt rev as high, lean more towards torque than peak power)
- Heavier than most 2-strokes.
In Europe we had many pushes for 4-stroke (the newest in date being the ID.Engine). But they dont offer pros over 2-strokes and it would require the motorists to learn something new. Even for rental karting, manufacturers were reluctants to offer a new engine
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Its mostly a weight to HP to cost equation. When you can put up 22 HP at a cost of $2500-3000 and a weight of under 50lbs (complete package) and not have crazy maintenance costs then you will have something.
Briggs - 36lbs - $1200 - 9HP
Tillotson - 38lbs - $1200 - 15HP
KA100 - 48lbs - $3100 - 22HP
Rotax Max - 51lbs - $3500 - 30HP
Tillotson has a package that could be close, but they are late to the party and the package has had a ton of design revisions and a poor reliability reputation. In addition, they seem to be focusing on the T4 package with hard tires which makes them effectively the same speed as a 206 on track.
Rotax has a reliable package, but lost people in the past with how they managed the package, design revisions, etc. People moved away to more stable platforms. Its gaining some traction again in Texas right now, we shall see where it goes.
Briggs is cheap (relative), low maintenance, and now has a stable established design. Great entry level platform that will be difficult for someone to unseat in the US. It is THE grassroots kart engine platform for sprint karting and has ties to various dirt platforms. KA100 is an expensive maintenance hog, but the design is well established and stable and has solid parity. I think it is the platform that someone could potentially displace due to 10 hour maintenance intervals alone. That seems to be the angle many Rotax club level folks are considering.
If someone had a reliable 15-20HP engine platform that cost $1200 and wasnāt a maintenance suck, it could maybe gain some traction. If they had something that was 20+HP and checked those boxes people would give it a shot. There is a reason they donāt. That is hard very hard to achieve that sweet spot in a 4-stroke. They get big, heavy, and expensive on you.
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They did. Vortex, TM, TKM, Biland and others. They never really took off. World Formula was actually a CIK class, not an engine.
Two valve OHV engines work well for karting, small enough, light enough, low enough and make just enough power.
When you try to get to even 80cc two stoke performance, four strokes make less sense. Youāre moving to four valves, OHC, much higher RPM and a heavier, taller package. The advantages of having something relatively low cost to buy and maintain go out the window once you step out of the industrial type engines.
Motorcycle manufacturers went 4 stroke because they had no other choice commercially.
Two strokes can be (and are) silenced when needed in karting. Another thing about the faster four strokes is that the lower frequency noise they make travels rather from the track compared to the two strokes.
Good thread on the options over time here:
This is the topic I meant to link
Perhaps a ābetterā option is the rotariesā¦.see: Aixro. They are also 2 cycle and emissions-poor. But they have an even more favorable power-to-weight ratio, and insanely long rebuild times.
I keep waiting for the LiquidPiston folks to finalize their engine, but perhaps the US Army will take all their capacity for dronesā¦
the US Motorpower 820 Copperhead was a potential 2 cycle domestic solution and had karting pedigree, but that project seems to be folded.
If I was going to try to find a 4 cycle motor, Iād go along the lines of the Honda horizontals, and thereās currently a Daytona 190 shifter groupā¦ the Cg is lower, and the power seems reasonable. No idea on what the rebuild intervals end up being. Also unsure on how much power the 2v gives up vs. the 4v Anima, but seems to be quite a bitā¦ At least thereās lots of Chinese support (read: parts availability, albeit of wildly varying specs.)
ooohhhhā¦.those could be lots of fun.
YEP rotors are very simple for anybody to fix. There seals have got TONS better. I dont see why they dont become popular. They are in alot hobby race cars now ā¦ They are seeing a comeback ā¦
I know this doesnāt fit your agenda but it appears to me that the karting market already has what it wants at this time. I get the feeling that you keep trying a convince everyone to buy a solution to a problem they donāt have.
Nope just think karting needs to have some different alternatives in karting power plantsā¦. To liven up kartingā¦
I donāt follow motorcross much, but I thought the 4 strokes there were given preference in the power outputs that made the 2 stroke uncompetitive?
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Whereās the Danger Dorito?
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There are a ton of engines that exist and can be bought and driven on practice days, even if there isnāt a class offered for it to race in. Nothing is stopping you from buying an Aixro or an Exciter or a 90s FSA engine and going out to flog it at will.
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How long have you been around karting? I can list a ton of engines that have come and gone. IAME alone used to have some crazy amount.
between 2000 and 2010 the market was absolutely flooded with new ideas. You could go to any kart show and it was new concept after new concept back then. Itās all settled down now because businesses didnāt want to continually lose a shed load of money trying to sell engines to a market of 5 people who might be interested in engine concept #6373. This was because in a market that priorities spec-classes, only a few win out in the end.
RIP Maxter, never forgotten
I think Chuckās got it right. 2 Stroke vs 4 Stroke basically doesnāt matter; itās mostly about power, weight and cost and, historically, 2 Stroke has been, cheapest, lightest and most powerful but other packages can work. Iād also argue that 2 Stroke is just as reliable once you compare like for like. They can all be fun to drive/race too.
On the noise issue, I live walking distance to two kart circuits and a motocross track. I canāt hear the kart circuits, even on an owner driver weekend (predominantly Rotax), I can sometimes hear the 4-strokes at the motocross track. Again, once you compare like for like (i.e. 30HP 2-stroke with a 30HP 4-stroke) the noise levels are comparable.
The spec vs open debate is essentially just a marketing exercise. Field spread in the old Formula Super A (the most open short circuit class that I can recall), wasnāt any wider than in any of the spec classes of today. I donāt think anybody can argue that spec classes have ended up being cheaper once theyāre run competitively. They have their place, but they shouldnāt be the foundation of the sport. The great thing with open classes is that, given a stable rule set and a little time, all manufacturers and tuners end up at roughly the same point of competitiveness. Any gains are tiny. It also allows for a healthy ecosystem of manufacturers, gives us all something to talk about and gives newcomers a simpler entry into the sport.
Karting scene is pretty healthy at the moment.
Letās get some skin in the game instead of telling us all we are wrong.
Buy a kart and a one-off engine you desire then find somewhere to race. Then report back to us. Get your own thriving community of T4 or E-kart club racing going. I promise itās not as easy as you think from behind the keyboard.
We can have a proper discussion on 2t vs 4t all day, but your rational of just having options, just because, doesnāt hold much water.
Put your money where your mouth is and buy something.
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Well in the next few years the E karting and Tillotson T4s will find there own niche in karting just takes time.. As far as karting we are Rental Karters or my grandson is.. No thoughts of buying a kart.. But we are big E karters and support that effort alot and trying to help get the news out there.. If we did do ICE would do Tillotson T4s more of a level playing field without competing with the no money no object people.. I have spent alot on Karting in last 3 years and in the 70sā¦ And forums are about giving opinions / thoughts / and info just exercising mine..
You are in for a rude awakening if you think any form of racing, āspecā or not, doesnāt have money is no object people.
I agree and thatās fine you just normally present your subjective feelings as objective facts.
Or stating karting as a whole āneedsā something when really itās just what you want.
I talked to someone who raced an ekarting world championship last year (ironically while we were both driving 206 kartsā¦) and they commented how it was very expensive. And not the travel part, but the practice time. The people who did the best were practicing all the time at home and for a long period before the championship at the facility that hosted. If people have the money to spend, it will get spent one way or the other.
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