HondaCRX

this is a HONDA! a 31cc 360 degree 4 stroke. conversion by carr precision. not only is it bigger than the ryobi but its a SOHC engine(single overhead cam).
me want!

DougT

My Feedback: (1)

Cool motor but did yu know the castings are made of concrete?

HondaCRX

huh? i know there heavy but its still cool

Tmoth4

My Feedback: (1)

I think it's cool. Would it run inverted? It could work in something like a 1/4 Tigermoth. I would guess it would have more torque than a 2-stroke so it could swing a big prop?

Jim

w8ye

My Feedback: (16)

I was interested in how the engine was made? There is not enough room under the vavle cover for the overhead cam sprocket?

Also there are two pushrod tubes coming from the cam just above the crankshaft? I then went to the Carr site and it has a drawing there with a arrow pointing to the top that depicts there being a cam in the top. Also, as being a little bit like a Y-S engine by using the crankcase as a booster? The drawing moves when you enlarge it.

It looks like it's worth talking about?

Can anyone elaborate on this? I've never seen one except the Carr pictures?

Enjoy,

Jim

Volfy

My Feedback: (23)

I believe that's only the oiling system. It acts a bit like a dry sump system, except it uses the crankcase as the circulating pump. The intake charge is inducted straight into the combustion chamber, so there is no super charging effect like the YS.

I kinda think Ryobi's wet sump system for ther 4strokes is simpler and works just as good. Their latest version is lighter and more powerful than the previous two. Might be close to the power of a 26cc 2stroke weedie.

HondaCRX

its an overhead cam, one of those things you thind is a pushrod tube is actually for thetiming belt. i think the other is for oil
[link=http://www.auav.net/honda/index.htm]video[/link]

HondaCRX

and heres the [link=http://www.honda-engines.com/min_main.htm]honda site[/link]

Dave_Gherardini

For starters. Thats a gx 31 or gx22. And its not OHC. It has push rods. I have a few of them and they are built like a typical honda. They are heavy. I have removed the oil foamer/slinger system and installed a remote tank to get the weight down to a respectible level. They will turn a 16x6 8k rpm. 18x8 6k. There are few folks using them on planes un modified and they are as reliable as you can get in any postion.
Honda has recentley(last year) come to market with a new smaller and lighter engine that is ohc but i have only seen one at a distributor but thay are selling them now. I would suspect the GX series engine was to heavy for the trimmer market but perfect for brush cutter and clearing saw market but those are small markets compared to the trimmer market. The IDC .(or ryobi or any other marketing name we know them as) that is marketed to mass merchants is a much lighter engine and cheap but makes a great engine to.

Here is a pic of the GX with the mods made. Ive removed the foamer/slinger housing and cut the crank off. Lost 12oz. I ve finished the engine but know pics of the finished mods yet. Next mod will be fuel systems and mag. Then ports.

w8ye

My Feedback: (16)

The overhead cam engine is the GC series.

Here's a description of the oiling system on the GX....

A clever rotary-slinger pumping lubrication system keeps oil in a completely misted state and circulates it using pressure fluctuations generated by the movement of the piston. Built-in passages effectively return the circulated oil to the oil reservoir from every part of the engine, and an oil return port positioned in the center of the reservoir ensures that oil cannot accidentally flow into the combustion chamber.

The GX rocker arms are set a .12 & .15 mm


Enjoy,

Jim

Dave_Gherardini

Yes, The GC is lighter and cheaper and still uses the principle oiling system the GX uses. Very ingenuis in my humble opinion. The GC is still very quality design and materials but built for larger markets. It will make a better rc engine than the gx but thats just my opinion. Its way better quailty than the IDC but if cannot be made lighter then it will only be a "better but heavier connversion".
heres a peek under the rocker cover of the GX

HondaCRX

ok! so its not a sohc engine thank you for telling me. i still want to find one somewhere.
heres the same one mounted on a plane

DougT

My Feedback: (1)

Even though they are different makes, it's amazing at the similarities between the Ryobi and Honda. With the rocker cover removed, the parts look almost identical in dimensions, placement, moments, etc. With the behemoth oil system removed, it looks much better and the carb/exhause/ignition look like a Ryobi as well.

Can't wait to see the OHC Honda in action.

HondaCRX

under the rocker cover , the honda looks almost identical to an os 4 stroke with the valve adjustment and everything

Stevepala

Dave G.

I've been thinking about using one of these engine (GX31) and was hoping you could give me the dimension of your engine after the mods.

How will the oil system work after the mod anf how much does it weigh?

I've asked about the GXV50 in other post, do you have any info on that one regarding oil and fuel system.

Thanks

HondaCRX

the 50cc CANNOT be inverted.

Stevepala

Ok, how about this one, Robin Subaru of Japan makes a 4 cycle 35 cc motor that put out like 1.8hp. It's used on gas power scooters. From what the scooter site claimed you have to mix the oil with the fuel.

The Robin America site was not working correctly so no info can be found there.

So what if the Honda 50 engine can't be inverted, could make a scale warbird swing some big blades if the motor could loose enough wieght.

HondaCRX

the engine MUST remain in the upright position to maintain proper lubrication.

Stevepala

Yes I agree it "MUST" remain upright for proper lubrication, but a barrel roll or loop as long as the pilot keeps positive G's won't cause the aircraft with this type of sump to fall out of the sky. Not all Lycoming and Continenal aircraft engine have dry sump inverted lubrication systems, but the FAA still allow them to fly.

I'm just looking for ideas and info.

Thanks

jerry dotson

HondaCRX.

I have been flying a GX 31 on my Fleet biplane for 4 years. It is very dependable. I get 7500 rpm on 18-6 zinger and 6800 on 18-8 zinger. Plane seems to fly better on the 18-8. Weighs exactly 5 pounds including CH ignition and battery. I also have a Ryobi 26cc. They are OK,lighter but not as powerful. I can't say which is better quality but the Honda looks a lot better. It is also more expensive. These people have it for $200.

http://www.tulsaenginewarehouse.com/catalog/honda/

Stevepala

Jerry

Would you be kind enough to provide some measurement on that engine. The overall width with carb and muffler, height and depth, and just width of head without carb and muffler.

Thanks

jerry dotson

Steve,
The oil sump is right about 6"wide. It is round....has a fan in there to make a mist and blow it through passages to lube the engine. That is why it can run inverted unlimited because the oil sump is round. The width is why I chose the Fleet. I had originally planned on a 1/4 scale J-3 but the fuse was not quite that wide. I don't run a muffler. It is quiet even with a straight pipe. I have an OS 60 FP that makes more noise. You can see the pipe in the picture.

Dave_Gherardini

Heres a pic of the cam. Single lobe with followers. Very neat design but for high rpms to much stuff. Im hopeing to get the total weight with stock ignition down to 4lbs. But so far 4.25. With CH ign system it could get below 4. But, i havent had the engine inverted for more than a few seconds. I might get to it this weekend.

Dave_Gherardini

Herses a pic of the upper crank case with the slinger. An any postion oiling system. Very cool...

HondaCRX

those are the coolest pics on this thread