Chinese CG125 Loud rattle/ tapping

[cooper99]

Hi all i have a chinese cg 125 with the old ohv engine in it and its making a loud rattling / tapping noise all the time apart from at idle, i checked my valve clearences and they are fine, its really bugging me, any ideas for what i could check, i have checked all of the engine mounts etc to no avail, thanks

[Colin the Bear]

Cam chain / tensioner?

[cooper99]

im afraid it doesnt have a cam chain its ohv

[Guest]

OHV = Overhead valves..?

driven by a chain that is inside the engine running from the crank to tell the valves when the engine is at the right place for valve position.

hows the oil level, low oil will give a similar sound. as theres not enough to get up top.

[cooper99]

na overhead cam (ohc) is driven by chain, ohv is has the cams in the crankcase and uses pushrods to open or close the valves so there is no cam chain. ill check the oil though... but i recon its ok as i only did it 300mile ago.

[Colin the Bear]

So a chinese pushrod engine that rattles. ? Bit like a cryptic crossword clue really. No make, no model.

Bent push rod. Worn push rod guide/bushing. Could be the clutch basket. Con rod bearings big or little end. Might even be piston slap. Could be an engine mounting come loose or broken away from the frame or in fact anything come unfastened. Chinese are famous for bits dropping off for one reason or another.

[cooper99]

lol sorry guys its a senke sk125 its pretty much an old style cg125, it runs perfectly fine, its just annoying i dont want the thing to just blow up on the way to work, i dont think my push rods are bent, its doesnt sound like a big end going i have had that before, however i had thought of the little end, would that make the bike burn oil, engine mounts are a possability i guess....

[Colin the Bear]

Not the exhaust baffle is it?

[cooper99]

thats a good point yeah could be somethin inside the silencer, ill have a look tommorow