Dr. Evil

iTrader: (12)

Well, I think there are such things like a 2/3 speed gear box. I know more stuff to worry about.

Well, that being said, I do know the CRF 450 for what it's worth, can wind pretty high in RPM. I would say possibly as much as a 2 stroke can.

That being said, I would think this could work.

Not to mention, since all the power is down low, you can gear up to accomodate the loss of RPM on the top end I would think.

Hmm.

Displacement, displacement, displacement.

So, I guess, there would have to be a .42 for buggies and a .56 for Truggies??

Double the size like in motocross??

newuserlosi8t

iTrader: (65)

i like the sound of that just like a 4 stroke mx

mattozx6rr

iTrader: (15)

for under 200 bucks it might be worth playing with but I still like the sound and smell of the nitro more. does sound pretty cool. wonder what kind of exhaust they are running?http://www.hobbypeople.net/index.php...e-engines.html

mattozx6rr

iTrader: (15)

ok, so it runs on nitro too. Trying to talk myself out of this but its getting harder! i have a spare old MBX5T sitting around that would make a good test bed.
Damn thing weighs almost a pound!

If nothing else it would get tons of attention at the track

pyromania

iTrader: (18)

Wow those 4-Strokes sound so sick. I would love to see them get into off-road racing, but it will take a while to do.

Now on the bad side, imagine a newb trying to disassemble and reassemble their engines.

+ YouTube Video

pyromania

iTrader: (18)

No tuned pipes are needed for 4-strokes. A simple silencer would do.

mattozx6rr

iTrader: (15)

I was thinking more a straight pipe out the side or back

Storydude1

iTrader: (7)

You'll need some sort of baffle. straight pipe won't let it breathe.

Advantage to a 4stroke nitro is TORQUE. They don't spin as fast, but they pull stumps.

There is a reason the air guys use the smaller 4 strokes to pull big props.

rotarynut

iTrader: (30)

4 STROKE SUPERIOR ??? you must be dreaming!!! a 2 stroke engine has way more HP per cc. of displacement hands down given they have the same disp., thats why in MX they had to double the engine displacement in order to get any performance out of them. 250 & 450cc 4 stroke = 125 & 250cc 2 stroke. More than likely why they went to 4 stroke is some enviromentalist whack job said they were "Poluuuting" the air. Keep Al Gore and his crowd out of R/C.
Do you realize that some of the .30 monter truck nitro engines are putting out almost as much power a you average Briggs & Straton push mower.
Hell you might as well bungy cord a lexan body to your mower and go racing
And for those who want to hear BBRRRRRRRUUUPP!! BBRRUUUUUPP!! go to an old folks home there's plenty of that in there.

RandyJones

iTrader: (26)

You haven't looked much at aftermarket pipes for 4-stroke MX then. Head pipe and silencer make a big difference on them too.

Of course in MX 4-strokes rule. 450cc has 200cc more displacement, 250cc has twice the displacement of a 125cc REAL-STROKE bike. I guarantee you build a 450cc 2-stroke, it will hurt the Air-stroke bike. AMA ruined MX. Not the EPA like everyone tries to blame.

I have rode the new 4-stroke bikes and they pull like a tank and RPM like a 2-stroke. Another bad thing we have to deal with the 4-stroke is to have a competitive motor, the rebuilds are close to $1,500.00

I do see it coming eventually though to RC and we will all just have to see how it pans out.

hambone

iTrader: (1)

It would've been a neat video if it was on a decent track and driven by a better driver. The truggy sounded good.

Tony Newland

iTrader: (53)

I've seen Damon's 4 stroke gt's in person a few times.... last weekend in fact. and they always look cool. I think the biggest advantage is the runtime. I think he said they go about 20 mins on a single tank... rediculous.

The absolute key is gearing and clutch on them. They turn a bit less RPM than .21s but that can be compensated for. As far as weight its pretty much even, a .21 with filter, clutch and pipe weighs in at around 16oz/1lb and thats what most .52 4 strokes come in at. So weight isnt an issue.

Several of us locally have banged around the idea of building a truggy mule to test with. Maybe that could be this winters project Always wanted to try it. 4 strokes are much more reliable and durable, they rarely need rebuilds and by running at much lower RPMs there is half the wear we normally see.

MotoGod

iTrader: (118)

Yeah I'd buy a 4 stroke engine for an RC without a problem. The biggest advantage to the 4 strokes in MX is you can ride them lazily and still be SCREAMING fast. Put the bike in 3rd and you can either lug it or scream it and it will pull you out of whatever problem you got yourself into....so I don't really think a single speed will be a problem on an RC car in the end.

Pros:

1. Torque for days
2. Less RPMs, means less wear and tear on the engine which means longer life
3. Tuning would probably be a snap on them, but I'm guessing here
4. Way better runtime

Cons:

1. Less HP per cc
2. slightly heavier (which could also be a pro depending on your setup I suppose)
3. Harder to tear down
4. More expensive when a rebuild is needed

So those cons don't look too bad to me, but the pros certainly look enticing! The same debate went through the MX world when 4 strokes came back (they were king many many moons ago!). I always loved my 2 strokes as well, but the first time I slung a leg over a 4 stroke...I was sold. It left you with SOOO much more energy to focus on riding instead of keeping the 2 stroke "on the pipe".

So if anyone produces a Truggy 4 stroker....I'll be in line to pick one up for sure! Just my take on it.

pyromania

iTrader: (18)

Don't tell me you actually believe some of those over hyped HP numbers.
I always laugh when I see those 4-5hp claims.

Dr. Evil

iTrader: (12)

Well, 4 storkes need more displacement to keep up /be better than 2 strokes.

I agree they are more work to disassemble. But, currently, in the MX world, the bikes weight about the same.

As far as 4 strokes being a tank, I don't agree.

OS made a sideways mount 4 stroke in the late 90s to go in a particular onroad car. The motor was strong on the bottom end.

The engine needed a 2 or 3 speed to keep up with the 2 stroke engines, but, it had advantages the 2 strokes didn't have. Hole shot.