200gy engine noise at higher rpm

[mgibsonaz]

My bike starts first kick, purrs like a kitten in lower rpms, stays quiet under load accelerating to speed , but when I back off the throttle to maintain speed it rattles and crackels until I reduce the rpms and it quiets back down at around 35 mph, I dont have a tach, but low rpm at that speed.
I did have to screw in the adjustment to only 1/2 turn out to pass smog, so I think it was way lean, but I have turned it back out and not making a difference. I am thinking of trying a valve adjustment, as they are still at factory settings. Just changed the oil and levels are good, but that was the first thing I thought was maybe not enough oil.

[SpudRider]

Is the engine making the noise, or is the exhaust system making the noise? In either case, it is well for you to adjust the valve lash. If the exhaust is making a popping sound, your carburetor jets might be too lean. If the engine is making the noise, you might have to adjust a manual, cam chain tensioner, et cetera.

Please give us more specific information regarding the noise, and its location.

Spud

[mgibsonaz]

the noise is definately coming from the engine....and kind of a vibration, rattle, and crackle.....when I let of the throttle and just putt its fine, but if i increase the rpms it starts the noise again.

[mgibsonaz]

is there a sticky for the cam chain tensioner, I am going to pull the tank and check the valves, cam chain tensioner sounds even more like it, as I listen it seems like a chain sound, but if i pull in the clutch everything is silent

[SpudRider]

I suggest you check for loose, engine mounting bolts. The cam chain would continue to make noise, even when you engage the clutch.

Spud

[mgibsonaz]

checked all mounts, it is definately a noise from within the engine, just seems to be there during higher rpms, but its not like Im winding it out, still hardly any throttle.

[Weldangrind]

Do you have a pic of the engine? If it's a pushrod motor, then there is no cam chain tensioner.

[SpudRider]

Please post photos of your engine, and show the area where the noise if originating.

Spud

[TheLoneRoger]

First post, so 'Hi'.

Not wishing to hijack your thread, but my LF200 GY-5 also seems to periodically get 'rough' at higher revs. Often, simply tightening the drive chain seems to make it better, but at the moment the chain seems almost too tight and it still shakes like a bad 'un at higher revs.

I can't say I could pin down a particular noise, just a lot of vibration.
Like you say, starts lovely, putts along sweetly at low revs, but nasty once you open it up.
Wish I knew why, but if I find out, I'll be sure to let you know.

Incidentally, I'm new to Chinese machines, and was just wondering how similar or not the various brands are when they share a similar model no. e.g. is a Zongshen 200GY just a re-branded Lifan 200GY (or vice-versa) or are they completely different? Is 'GY' just some kind of Chinese code for 'Trail/Enduro model' or is there more to it?

Anyway, Im pretty please with my Lifan - I had an XR200 before, and although there are obvious differences in build quality, it's not nearly so obvious as the price difference! It's a lot of fun-per-buck, and so what if the plastics break if you sneeze at them - they're replaceably priced!
Cheers
Roger

[Weldangrind]

Welcome Roger!

"Replaceably priced" is a terrific line.

To confirm, the Zongshen product you refer to is a Yamaha clone, and entirely different from your Honda clone. I don't know the origin of the GY reference.

I'd be checking the motor mount bolts to see if they're the source of the vibration.

[SpudRider]

Welcome to these forums, Roger. We are glad you joined us.

Check all the bolts for you engine mounts, and secure them with red locktite. Loose engine bolts are frequently the cause of the problem you described.

You are correct; the Chinese use the GY designation for dual sport motorcycles. There are 3 basic types of Chinese, dual sport bikes, based upon the type of engine the manufacturer copies.

The most common type of Chinese, dual sport bike is a hondoid, which employs a copy of a Honda engine. My Zongshen 200GY-2 is rarer; it employs a copy of a currently manufactered Yamaha engine. Finally, the Qinggi/QLink/Konker motorcycles employ copies of Suzuki engines.

Spud

[SpudRider]

Originally Posted by Weldangrind

Welcome Roger!

"Replaceably priced" is a terrific line.

To confirm, the Zongshen product you refer to is a Yamaha clone, and entirely different from your Honda clone. I don't know the origin of the GY reference.

I'd be checking the motor mount bolts to see if they're the source of the vibration.

You beat me to the punch by a minute, Weld!

Spud