Yup, exactly! I was a 125 guy and nothin was better....till I got to twist a YZF 250 off the line. I jumped off, wide-eyed, thinkin..."Holy crap. Really? That's the fastest effin couch on the planet!" Too easy...

I'm thinkin it might be the same in RC if someone is thorough enough. Gear up a little everywhere (spur, pinion, f/r diff input), toughen up the driveline/clutch a little, tune suspension to handle the weight, and roll on with a smile! If the engine is built well enough it can scream between 9 and 12K rpm.

As of now 8th e-buggy is already exposing some of the torque issues in the drivelines and how torque changes suspension tuning a little. BL torque is nothing compared to what 4-stroke can do after gearing up. Interesting stuff...

Great Evil,

Just what we need, yet another motor to choose from. LOL. I know there were a few people taking some of the 4-stroke airplane motors and putting them in cars/trucks some years back. It is a sound idea, but not sure on the practical use. The current issue is the lack of RPM for a given size motor when compared to the same size Nitro motor. That is to be expected as MX has proven with the 250 vs. 450. In time I think it could work, just not sure when. The added use of a two or three speed clutch/spur gear would be a big help, though not sure if it would work well in the offroad arena as the gears are pretty exposed.

I also would like to see this, and they are less to rebuild than you think. First, they are ringed engines. So $20.00 for a new ring and the engine is rebuilt! And valve adjustments are needed, but are very simple to do. I've owned around 20 or so 4-stroke engines throught the years and prefer them in my airplanes, I've even had two 4-stroke helis. I also run all my 4-strokes on 30% heli fuel. (cool power) amazing run time to boot...

I vote yes!

How bout a Wankle?

bumping this for friend

4-stroke has real potential if it's ever properly developed. There are a few misconceptions here:

It is not true that 4-stroke is less powerful than 2-stroke of the same displacement. While that's generally true (especially in our model engines), in motorcycle racing it's no longer the case. A pro level 450cc bike makes more hp than the 500cc 2-strokes used to, same is true of the 250ccx4 vs. 250ccx2 and MotoGP. 2-stroke engines were developed to the point that they were not finding ways to make them appreciably faster from year to year. All of them are spinning more RPM than a 2-stroke will ever be capable of now because they've figured out how to prevent valve float. The main reason our model engine 4s engines don't spin fast is because it's not usable for airplanes. There is a maximum usable speed for propellers.

Lets keep the number one factor in mind of why the MX world made the switch and manufactures were forced to develop the 4 strokes... The EPA mandate that 2 strokes were to dirty to be used in the motorcycle and off-road areas. It happened to snowmobiles as well. This forced the manufactures to look at increasing the performance of the 4 strokes to where they are today. The ability and technology is there but until it is forced to be developed it will not happen...

I would dissagree that 4 cycle is cleaner.

Cleanest, most fuel effecient, lowest oil consuming snowmobile you can buy right now is the Ski Doo 600 E-Tec 2-Stroke (and Ski Doo makes the most effecient 4 stroke also)

Stock 1995 CR500 HP is 54hp, Stock CRf450 is 49hp

Now, on the track, the 450 is usually faster (it is 15 years newer in suspension, frame, tires, etc...) and has a much easier to race powerband

But, the CR500 does make more (and if modded, 70+hp on a stock bottom end, and 90+hp is available fully tricked out)

Ringed engines are cheaper....if you're only replacing rings. If you blow the valve train it becomes a nightmare to fix ;-) At least on the wallet...so that's what I was referring to....rings are dirt cheap, but valves and heads and springs and timing chains (if the model version has one?)...etc etc etc Just more moving items in there...do depending on what happens will depend on how much your wallet hurts.

MX 2 stroke rebuild was like $125 or so....which I did @ twice a season on a good year..... 4 stroker rebuild was more like $750, but only needed it every few seasons at the club level.

Catastrophic failure is WAY more on a 4 banger though ;-)

You mean they don't give away those titanium valves, skirtless pistons and all the bearings for all those moving parts? lol

4 strokes gained allot in a short amount of time, with copious amounts of money and R&D to get them there. Yea, a 50hp 11,000 RPM, 500cc engine is possible, but the price of the bikes did almost double allong with it. You basically have a single cylinder Indy Car engine when you are all said and done, and it's as durable as a $3 watch after you dropped it a couple of times.

Imagine if they had put the same efforts of R&D into 2 stroke technology? Hell, the 95 CR500 didn't even have a Power Valve on it! Litterally still mid 80s engine technology.

The only major player in the last 10 years to pursue any 2 stroke technology is Bombardier and Rotax. FICHT and Direct Injection has brought 2 stroke engines as the cleanest in the Marine (JetSki AND Outboards) allong with Snowmobiling. They actually use less oil than a 4 stroke counterpart.

Dumb thing about dirt bikes and atv's is the fact that in some states and national parks, they just flat out banned 2-strokes rather than give the industries a chance to clean themselves up. It's as intelligent a move as when the gov mandated cat. converters in the 70s on cars.

I have a 4 stroke OS if someone wants to try it

Even a four stroke wouldn't match brushless power in 8th scale cars. Electrics are around 90% efficient with the power generated and have full power at 1 rpm. Mechanical engines aren't even close to that kind of efficiency. You can literally set up a 1/8 buggy with 4 hp with a brushless setup and it uses ALL of it versus a nitro engine which will waste half of the power in noise and smoke.

From what I have seen, nitro engines put out the right balance of power and more torque is not needed. I spend half my time trying to figure out how to get rid of torque in my electric cars. Most of the developments are around taming the torque in the 1/8 cars now.

It would be cool to see a thumper like engine in 1/8. What is probably holding it back are ROAR rules so there really is no incentive for it to be developed if it truly will run better than a typical nitro engine. Hopefully, some guy in his garage will figure it out and if enough people start showing up with them, things will change.

Electric 1/8 is only around because a few enterprising people figured out how to make it work cheaply before mfg's even considered it a possibility. All the mfg designs now are basically copies of rc-monster, tekno, rc product designs, from five years ago

HRC's Honda CR450f's make 70+ hp on the track today. I have never heard of a CR500 built to make that hp # for motocross because they were so hard to ride.

Snowmobiles are probably a better study since their weight and clutches allow engine builders to go crazy with the power and they have developed them over the time that the motorcycle guys have given up on 2-stroke.

For model engine purposes I think the potential of the 4-stroke is easier tuning, better run time and a more usable, lower RPM powerband.

if 4 stroke motors are what it takes to overcome all these electric shenanigans going on now im all for it :D