top end rebuild how often?

[jerickw]

hello guys i have a 2006 gy-2 style cg 200 with a zongshen 250 that i converted to a enduro style dirtbike. my question is with pure dirt use how often do i need to rebuild the motor with these chinese motors? I never really go above third gear but i spend alot of time at high rpm's. i was just gonna do the standard 150 hours that id do with a ktm or honda but was not sure if its more or less often since this does hold more oil then a dirt bike

thanks in advanced!

[Ariel Red Hunter]

Originally Posted by jerickw

hello guys i have a 2006 gy-2 style cg 200 with a zongshen 250 that i converted to a enduro style dirtbike. my question is with pure dirt use how often do i need to rebuild the motor with these chinese motors? I never really go above third gear but i spend alot of time at high rpm's. i was just gonna do the standard 150 hours that id do with a ktm or honda but was not sure if its more or less often since this does hold more oil then a dirt bike

thanks in advanced!

I don't know which kind of engine you have. Is it push-rod, or overhead cam?

[jerickw]

Originally Posted by Ariel Red Hunter

I don't know which kind of engine you have. Is it push-rod, or overhead cam?

the the air cooled zongshen 250 and it is a pushrod style

[jerickw]

heres just a picture of the bike mid ride yesterday still runs great good compression as of now at least just pops alot since i cant find the exhaust gasket for the point that it connects to the motor

[Ariel Red Hunter]

Originally Posted by jerickw

the the air cooled zongshen 250 and it is a pushrod style

The pushrod engine is one of the longest lived little engines ever built. It was originally designed to operate in absolutely abysmal conditions. A good air cleaner, and thousand mile oil changes will make this engine run a very long time. So will valve clearance check-ups. If you don't have a speedometer, 1000 miles is about 30 hours at an average speed of thirty-five miles per hour. As long as the cylinder compression is good, the engine is good to go. The copper o-ring for the Honda 230 fits, and is much better than the original head pipe gasket that comes with these little hummers.

[jerickw]

Originally Posted by Ariel Red Hunter

The pushrod engine is one of the longest lived little engines ever built. It was originally designed to operate in absolutely abysmal conditions. A good air cleaner, and thousand mile oil changes will make this engine run a very long time. So will valve clearance check-ups. If you don't have a speedometer, 1000 miles is about 30 hours at an average speed of thirty-five miles per hour. As long as the cylinder compression is good, the engine is good to go. The copper o-ring for the Honda 230 fits, and is much better than the original head pipe gasket that comes with these little hummers.

thank you for the information! i have a odometer i broke the speedo but odo works still at least and ive been changing oil every 10 hours so far since ive been doing dirt riding. also sidenote do you by change know an actual oil filter that fits these? the mesh filter is a joke. i have yet to recheck valve but i got the engine installed 2 months ago and with the gy-2 frame you have to drop the motor to even check so ill prob wait till the end of the season to check

[2LZ]

As ARH states, a dang long time , especially if maintained. It's not like the good-ol'-days where you had to do a bore, piston and rings every two season on your 2 stroke.

[Ariel Red Hunter]

Originally Posted by jerickw

thank you for the information! i have a odometer i broke the speedo but odo works still at least and ive been changing oil every 10 hours so far since ive been doing dirt riding. also sidenote do you by change know an actual oil filter that fits these? the mesh filter is a joke. i have yet to recheck valve but i got the engine installed 2 months ago and with the gy-2 frame you have to drop the motor to even check so ill prob wait till the end of the season to check

There is no other oil filter for that engine that I know of. That's why you should change the oil frequently, like you are doing. 10 hours is about 350 miles, if your average speed is 35 mph. You can change at 20 hour intervals, if you so choose. There is a reason for that oil filter. For the region of the world that this engine was originally designed for, getting people to even change oil at all was a big problem. Expecting them to change an un-obtainable filter was just too much.

[jerickw]

Originally Posted by Ariel Red Hunter

There is no other oil filter for that engine that I know of. That's why you should change the oil frequently, like you are doing. 10 hours is about 350 miles, if your average speed is 35 mph. You can change at 20 hour intervals, if you so choose. There is a reason for that oil filter. For the region of the world that this engine was originally designed for, getting people to even change oil at all was a big problem. Expecting them to change an un-obtainable filter was just too much.

yeah i guess that does make sense. i saw somewhere someone matched one that fit but i cant quite remember what forums it was on i may have to look a little if not just cleaning it and the magnetic oil plug should be enough with the frequency. thanks for the info

[Mudflap]

CG engines have a centrifugal oil filter under the clutch cover, attached to the crankshaft. It does a good job at trapping the fine particles. Quick and easy to clean once the clutch cover is removed.

[Weldangrind]

The stock screen is identical to what is used in the Honda XR200 OHC motor. It works fine as long as it is cleaned every 10 hours or so.

[wilserchinarider]

Originally Posted by jerickw

i have yet to recheck valve but i got the engine installed 2 months ago and with the gy-2 frame you have to drop the motor to even check so ill prob wait till the end of the season to check

Sometimes it's tight, but you can usually get the valve cover off without lowering the engine. Sometimes people will trim or grind away a bit of the valve cover fins to make valve cover removal possible / easier.

[Ariel Red Hunter]

Originally Posted by Mudflap

CG engines have a centrifugal oil filter under the clutch cover, attached to the crankshaft. It does a good job at trapping the fine particles. Quick and easy to clean once the clutch cover is removed.

Thank you for that info. I didn't know that. I'll remember it, though.

[jerickw]

Originally Posted by wilserchinarider

Sometimes it's tight, but you can usually get the valve cover off without lowering the engine. Sometimes people will trim or grind away a bit of the valve cover fins to make valve cover removal possible / easier.

ok thanks for the info ill have to see about grinding it down next time a remove it because ive tried taking it off before while on the bike just didnt have the clearance hopefully doing that will let it slip off

[Mudflap]

On some bikes the valve cover will clear the frame if the rocker arms are in a certain position. If it almost comes out, try rotating the crankshaft and see if there is a spot where you can wiggle it out.