Tyrant I don't know what engine type, 2 or 4 stroke, you're running at this point. My comments are for those running 2 strokes.
I've a 66 cc China girl that had over 600 hrs. of run time two years ago when the hr. meter died and she's still running great...it's certainly not close to box stock but your right 1K isn't much even for the much maligned CG, even for a straight kit motor, though proper engine care and riding technique is important for really extended motor life. If you are fortunate enough to buy a relatively well balanced & clearance 2 stroke motor or have the skills necessary to build one then you have a good foundation for long service life. Lowering the engine heat and improving the motors lubrication, which also lowers heat, are the next steps in longevity for these little 2 strokes.
Oddly enough some modifications to improve horsepower will also greatly improve engine cooling and lubrication (cooling) like the addition of a well designed aluminum head that acts as a huge heat sink, or adding a reed valve induction with piston window and machining an extra port passage will not only flow more air, but the added fuel/oil mix will also cool the wrist pin, upper rod & interior of the piston better due to the piston window. Higher compression is a good goal but only to a certain point, too much is actually detrimental and destructive as well. A modest bump to compression for performance is fine.
As to riding technique on a 2 stroke: keep fuel flowing to the engine for cooling, don't try to use compression breaking especially on long downhill stretches or idling at stops; blip the throttle continually to keep fuel mix flowing to the motor. These 2 stroke's are air cooled and need air flowing around the motor to cool so avoid long periods of idling, but they are also fuel cooled so idling at stops starves them of both air flow externally and the internal cooling fuel flow as well and they get overheated quickly even in winter weather at stops, fuel flow is the only source of cooling at idle..so blip that throttle.
One final aspect wide open throttle, all the time is a bad thing, some throttle on all the time is a good thing. The well modified China girls can run 13,000 rpm but won't last too long at these elevated revs. Long sustained pulls at 8,000 rpm's or so with these modified motors will add a lot of wear on the motor but the real problem is the toll these speeds place on the rest of the bikes components over time. I like speed but limit them to short bursts on my bikes 2 stroke, four stroke or electric.
High rpm's on a highly modified CG 2 stroke can benefit from a bit of retarded ignition timing after 7k or so, normal advance curve up to 7k... just the opposite of 4 stroke design where advance continues up the rpm scale. I find the stock CDI is fine for 95% of my riding on slightly modified China girls.
Most may be already be aware of these things & many may disagree with some or all of what I've expressed, but others may benefit from some of my observations..
Hope your engine (4 or 2 stroke) holds up for many more enjoyable miles and again welcome to the forum.
Rick C.
I've a 66 cc China girl that had over 600 hrs. of run time two years ago when the hr. meter died and she's still running great...it's certainly not close to box stock but your right 1K isn't much even for the much maligned CG, even for a straight kit motor, though proper engine care and riding technique is important for really extended motor life. If you are fortunate enough to buy a relatively well balanced & clearance 2 stroke motor or have the skills necessary to build one then you have a good foundation for long service life. Lowering the engine heat and improving the motors lubrication, which also lowers heat, are the next steps in longevity for these little 2 strokes.
Oddly enough some modifications to improve horsepower will also greatly improve engine cooling and lubrication (cooling) like the addition of a well designed aluminum head that acts as a huge heat sink, or adding a reed valve induction with piston window and machining an extra port passage will not only flow more air, but the added fuel/oil mix will also cool the wrist pin, upper rod & interior of the piston better due to the piston window. Higher compression is a good goal but only to a certain point, too much is actually detrimental and destructive as well. A modest bump to compression for performance is fine.
As to riding technique on a 2 stroke: keep fuel flowing to the engine for cooling, don't try to use compression breaking especially on long downhill stretches or idling at stops; blip the throttle continually to keep fuel mix flowing to the motor. These 2 stroke's are air cooled and need air flowing around the motor to cool so avoid long periods of idling, but they are also fuel cooled so idling at stops starves them of both air flow externally and the internal cooling fuel flow as well and they get overheated quickly even in winter weather at stops, fuel flow is the only source of cooling at idle..so blip that throttle.
One final aspect wide open throttle, all the time is a bad thing, some throttle on all the time is a good thing. The well modified China girls can run 13,000 rpm but won't last too long at these elevated revs. Long sustained pulls at 8,000 rpm's or so with these modified motors will add a lot of wear on the motor but the real problem is the toll these speeds place on the rest of the bikes components over time. I like speed but limit them to short bursts on my bikes 2 stroke, four stroke or electric.
High rpm's on a highly modified CG 2 stroke can benefit from a bit of retarded ignition timing after 7k or so, normal advance curve up to 7k... just the opposite of 4 stroke design where advance continues up the rpm scale. I find the stock CDI is fine for 95% of my riding on slightly modified China girls.
Most may be already be aware of these things & many may disagree with some or all of what I've expressed, but others may benefit from some of my observations..
Hope your engine (4 or 2 stroke) holds up for many more enjoyable miles and again welcome to the forum.
Rick C.
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