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ntender
02-01-2014, 11:28 AM
Hi guys

Does anyone know how to reduce the tappet noise on this 200cc pushrod engine (can the engine make even be identified?) The factory clearance is supposedly 0.05mm intake and exhaust. But is this hot or cold? I tried it both ways. It still makes too much noise for my liking after just 5 minutes of riding from cold. I've even got it where there's practically no clearance on both valves when cold, and still it's noisy. This engine only has 1400km, or 870 miles on it. People say it should be a bit noisy, but how much is too much? Is there some trick with these pushrod engines?

Any help would be appreciated.

http://i1264.photobucket.com/albums/jj486/ntender/MotomiaPachinoengine.jpg

SpudRider
02-01-2014, 05:13 PM
That's a typical clone of a Honda pushrod engine. :) You might want to check the valve lash specifications in the following thread.

http://www.chinariders.net/showthread.php?t=977

The valves in these bikes always make some noise, even if the valves are adjusted properly. Also, slightly loose valves are much better than slightly tight valves. Always remember, slappy valves are happy valves. :)

What motor oil are you using?

ntender
02-02-2014, 03:58 AM
Thanks for the response.

I've checked out the links you gave me.

At this point the oil I'm using is Castrol High Mileage. I think it's 20W60. I'm using it as a running-in oil. Remember, I've only ridden around 1400km. I was hoping this particular oil would deal with the bigger clearances more effectively, but it doesn't. The noise is the same.

We also have a warm climate here. It's summer now, so temps outside are around 30 to 35 Deg C, or 85 to 95 Deg F, so that also plays a part.

SpudRider
02-02-2014, 04:26 AM
I hope you are enjoying the summer weather in the southern hemisphere. :) Your choice of motor oil is excellent.

The valves in these engines normally make a fair amount of noise. Unless you are hearing a clapping sound, or some other unusual noise, I don't think you have anything to worry about.

katoranger
02-02-2014, 09:01 AM
Noise is normal. All the pushrod engines make noise.

Weldangrind
02-02-2014, 12:41 PM
I indicated the engine model in your other thread, but it bears repeating here. It is a CG200, which is based on the Honda CG125 that has been bored and stroked.

I've never tried it, but I'm sure you could loosen the bolt in the top of the valve cover to confirm oil flow to the top end. I recommend that you remove it completely while the engine is off to determine how long the bolt is, and also to note any presence of oil. You could then start the engine, let it idle for a moment and then loosen the bolt to see if oil seeps out. Please be careful, since I'm not sure how much oil pressure would be behind that bolt.

ntender
02-03-2014, 03:33 PM
Thanks for the useful info guys. I appreciate the responses. It's just that I've never owned a bike with a pushrod engine before. I think I'll take it out on a looong ride somewhere to get a better feel for it.

bogieboy
02-03-2014, 03:53 PM
I am curious the oil choice reasoning? I use 10w-30 in my chinabike (also a cg200 pushrod engine) and thats what i broke it in on... I also chose to do a "hard" break in... I.e. Ride the heck out of it, revving hard and engine braking hard... 99% of your breakin is done in the first 20-30 miles...if its babied, theres a chance you dont get your rings properly seated and you may never get the true potential out of the engine... At least thats my opinion...

ntender
02-03-2014, 06:08 PM
The idea with the oil was that it might deal better with bigger clearances, like a thicker oil may do. This oil doesn't seem to do that. It's more experimenting than anything. Also, where I live, the chance of temps getting down to freezing is very small, but it can get warm, about 35 Deg C, or 95 Deg F, hence this type of oil.

My biggest problem is I'm not totally convinced about the reliability of these bikes, so the idea is to preserve the engine. I don't think I've exceeded 7000 RPM in 900 miles from new. I've owned a different chinabike, an overhead-cam type, and that seemed fine in over 23000 miles. But hey, that's me, I worry about stuff going wrong.

Weldangrind
02-03-2014, 08:33 PM
Dude, if you knew how these pushrod motors were punished in Asia, you wouldn't be concerned. :D

ntender
02-04-2014, 01:50 AM
what kind of life can one expect with these motors, distance-wise?

SpudRider
02-04-2014, 01:53 AM
what kind of life can one expect with these motors, distance-wise?

I have ridden about 62,000 miles (100,000 kms) on my Zongshen 200GY-2 (Sierra 200). :)

http://www.chinariders.net/showthread.php?t=13119

Weldangrind
02-04-2014, 02:26 AM
I would expect a pushrod motor to go even further, since there is no cam chain and no tensioner. The single cam lobe (same lobe bumps the intake and exhaust) runs off of a gear from the crank, and it is bathed in oil. A good recipe for longevity.

Change your oil frequently, clean the screen each time, set the valves every second or third oil change, remove the clutch cover and clean the centrifugal portion of the oil pump once a year and enjoy it.

bogieboy
02-04-2014, 11:53 AM
The idea with the oil was that it might deal better with bigger clearances, like a thicker oil may do. This oil doesn't seem to do that. It's more experimenting than anything. Also, where I live, the chance of temps getting down to freezing is very small, but it can get warm, about 35 Deg C, or 95 Deg F, hence this type of oil.

My biggest problem is I'm not totally convinced about the reliability of these bikes, so the idea is to preserve the engine. I don't think I've exceeded 7000 RPM in 900 miles from new. I've owned a different chinabike, an overhead-cam type, and that seemed fine in over 23000 miles. But hey, that's me, I worry about stuff going wrong.

Ok, i can see that thought... I have always been of the opinion of the manufacturer says to use a certain weight thats what i will use...LOL thats all...

As spud has said these bikes are quite reliable given you keep the nuts and bolts tight...and i agree with WaG...they punish the snot outta fhese engines across the pond... I have no qualms about revving mine to 8-10k rpm routinely...i rev it til it dont want to go no more...LOL

ntender
02-04-2014, 12:00 PM
Well I feel a little better about the durability issue now. It's no fun riding if you think that at some point the piston's gonna escape and whack you in the twig and berries if the revs get up there a bit.

Thanks for all the contributions as far as maintaining and actually using these little bikes goes.

Weldangrind
02-05-2014, 12:55 AM
The good news is that replacement parts are cheap as chips on www.taobao.com (http://www.taobao.com). As far as the twig and berries go, a cup is cheap insurance. :D