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CRRC Pro 40cc petrol (kit engine)

Started by Brian Cooper, October 26, 2009, 09:09:37 am

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Brian Cooper

October 26, 2009, 09:09:37 am Last Edit: October 28, 2009, 17:52:36 pm by Brian Cooper
For those who don't mind getting their hands dirty (and saving a few quid) CRRC Pro are doing a 40cc kit built engine.
Basically, it comes in lots of little packets and we just bolt it all together.  Seemples.  :)

The first start was a bit tedious due to the plug gap being too wide, but once it was sorted out it settled down and ran well.  :af

After only 40 minutes of running in, it feels silky smooth and is happily turning a
20x8 Graupner G-Sonic prop at 7,000 rpm.
It feels very strong and powerful.  :)

Further experiments with different props are planned for when it's fully run in and running on a less oily mix of fuel.   :af

B.C.

Hairyflier

I did a build thread on here a little while ago but it may have been lost in one of the system crashes. Run mine on a 20x10 - superb.  :af
I do not agree with what you have to say, but I'll defend to the death your right to say it. Voltaire

Alan

They look fun, and cheap for a 40cc lump. Lots of places will build it for you too, for about £15.
I dunno...

Brian Cooper

The engine has now had the benefit of a couple of hours of running-in time and the carb has been fine tuned.

It is still running on a slightly oily mix of fuel, but it is now smoothly turning the
Graupner G-Sonic 20x8 prop at 7,500 rpm.   :)

This is very respectable performance.  I'm impressed.  :af

B.C.

Mudders


paulplane

I've seen the kits on ebay. Might treat myself to one. I'm a bit short on engines, especially petrol. Bought a Thunder Tiger 91 new version today, so a petrol is next... :)
Don't be a don't be, be a doobie!

Brian Cooper

Quote from: Mudflap on October 29, 2009, 19:31:51 pm
What mix are you using Brian?

Mat :)


It started life on 35:1

It is currently on 40:1

It will run on 50:1 after another hour or so of running time.  :af

Oil is Bel-Ray HR1 synthetic racing oil.  :)

B.C.

dogshome

18*8 G-Sonic 8,000RPM with 10 minutes running so far.
肉(ròu)包(bāo)子(zi)打(dǎ)狗(gǒu) (meat+bun(2nd and 3rd)+hit+dog)
Literally: To hit a dog with a meat-bun

Scram

Quote from: dogshome on January 23, 2010, 16:06:28 pm
18*8 G-Sonic 8,000RPM with 10 minutes running so far.


OOOH   :o

I have seen 6,200 rpm on mine running a 20 x 10 wooden EAT prop after about an hour running in on 30:1 with Castrol 2T oil.

Produces black goo from the exhaust   :'(

Are we not at all concerned at the instruction in the manual not to exceed 6,500 rpm??   :study:

J
Egg beaters make Scram - bled eggs. Sceadu 50 HPM, Sceadu 50 SWM, X-400
Wizard Compact. E.G. Alula, E-Typhoon, Typhoon, Vampire, Mini-Vec, Aresti 2m, Speedo, Deuces Wild.

dogshome

8000 isn't excessively high for non-flywheel equipped 40cc two stroke. Bigger capacity chainsaws do a fair bit more than that.

It's not run in yet and I admit that a 20*8 will give more thrust and be quieter though.

6500 is a bit on the slow side to me.


Black goo is normal. Grey goo is something to worry about  :)
肉(ròu)包(bāo)子(zi)打(dǎ)狗(gǒu) (meat+bun(2nd and 3rd)+hit+dog)
Literally: To hit a dog with a meat-bun

dogshome

20*8 Graupner Sonic - 7,000 RPM and a bit more after some running.


Just pinched the DL out of the Megawot for something else...

CRRC 40 will prop hang and make steady progress vertical on the 7' WOT. Not nearly as much oomph as the DL on a pipe, but for just over £100 it does the job.

Noise testing isn't good though - 84dB on LHS, but much more on RHS - and it's all intake noise that side.
肉(ròu)包(bāo)子(zi)打(dǎ)狗(gǒu) (meat+bun(2nd and 3rd)+hit+dog)
Literally: To hit a dog with a meat-bun

dogshome

Hopefully more is less (volume, baffles and dB!)

肉(ròu)包(bāo)子(zi)打(dǎ)狗(gǒu) (meat+bun(2nd and 3rd)+hit+dog)
Literally: To hit a dog with a meat-bun

tiposx

August 29, 2011, 20:25:34 pm #12 Last Edit: August 29, 2011, 20:36:02 pm by tiposx
Here is one hauling round a 1/4 scale model that weighs around 20 pounds. I think we are using a 20/8 prop
MS 22 aug 2011.wmv
And this is the first time the engine was started:
crrc 40 test run.AVI

AlexC

I had problems with engine trying to run backwards, fitted this ignition unit from Agape racing and now runs better.

http://www.agaperacingandhobby.com/viewitem.php?productid=223