Ghost racer 7g poor manufacturing

[Riggsz]

YOU GET WHAT YOU PAY FOR! After installation I installed the proper amount of 10w 30 synthetic oil & proper low octane gasoline in gas tank. The motor started just fine & let the motor break in for 1/2 hr running straight at idle. Periodically also starting before road test. During said road test I ran the engine at low to mid rpm for a 1/4 mile or so then slightly increased rpm as to insure proper break in as I have purchased & installed over a dozen Huasheng 49cc 4 strokes in past. After increasing rpms the motor started cutting out slightly & smoke & oil was pouring out on exhaust & into carb from vent hose. I have ran tests on this engine after this mishap & it seems the oil rings in motor are faulty. Motor being under warranty still I called Gas Bike.Net where I purchased the kit & after 40 attempts to speak with support tech or to file a warranty claim no such luck. Also emailed support with no reply & they are ignoring the fact that they do not want to deal with this problem. I decided to repair engine myself & have found broken rings, compression ring installed upside down, & the piston installed backwards with arrow facing towards exhaust. After honing scratches from cylinder & new rings properly installed with piston facing in correct alignment the motor is running great. The transmission with it's one way 10 tooth sprocket is another story lol Ha!

 

[Imthegrt1]

That's bites ...check them of my list

 

[MotorBicycleRacing]

YOU GET WHAT YOU PAY FOR! After installation I installed the proper amount of 10w 30 synthetic oil & proper low octane gasoline in gas tank. The motor started just fine & let the motor break in for 1/2 hr running straight at idle.

Periodically also starting before road test. During said road test I ran the engine at low to mid rpm for a 1/4 mile or so then slightly increased rpm as to insure proper break in as I have purchased & installed over a dozen Huasheng 49cc 4 strokes in past. After increasing rpms the motor started cutting out slightly & smoke & oil was pouring out on exhaust & into carb from vent hose. I have ran tests on this engine after this mishap & it seems the oil rings in motor are faulty. Motor being under warranty still I called Gas Bike.Net where I purchased the kit & after 40 attempts to speak with support tech or to file a warranty claim no such luck. Also emailed support with no reply & they are ignoring the fact that they do not want to deal with this problem. I decided to repair engine myself & have found broken rings, compression ring installed upside down, & the piston installed backwards with arrow facing towards exhaust. After honing scratches from cylinder & new rings properly installed with piston facing in correct alignment the motor is running great. The transmission with it's one way 10 tooth sprocket is another story lol Ha!

Idling a brand new motor is the worst thing you can do to it.
You want load on the rings and you want to rev it out to seat the rings right away.

A slow low ring load break in makes for a bad ring seal and a glazed cylinder.

I am pretty sure that the arrow is supposed to be facing the exhaust.
I have a few Haushengs and a few Honda GX 50's but I never had to take one apart.

However yours is the second complaint I have heard about bad rings in a Huasheng 7G
kit from Gasbike unless you are the same guy?
Gasbike has a history of ignoring warranty or missing parts complaints.

Where did you get the replacement rings from?
Did you take pics?

Glad to hear that you got it running good......

 

[butre]

Idling a brand new motor is the worst thing you can do to it.
You want load on the rings and you want to rev it out to seat the rings right away.

A slow low ring load break in makes for a bad ring seal and a glazed cylinder.

this is good advice, but I do have something to add: you do want to idle it until it's warm before you go revving it out, and you don't want to rev it out without load. let it sit until warm, and then ride it hard. just giving it throttle is just as bad as babying it during break in

 

[Riggsz]

Hey SoCal, As far as I know I am the only one that has had this problem with the 7G motors.Everyone has has there theorys on breaking in 4 stroke engines. I have had much luck with the old school method which is heat cycles. The "three heat cycle" seems to be most popular. Turn the engine on, let it idle for 10-20-30 minutes, give it a couple of revs, then shut it down. Cool off completely. Repeat. Repeat again. Ride @ 1/2 throttle for 20 miles or so & shut down. Let engine cool down ride again @ 3/4 throttle for 20 miles shut down cool off. Now full throttle is possible for short bursts @ idle or riding. With most new 4 strokes the honing process is much smoother & not needing such a long break in process & the rings seat much faster. All the new parts in the engine are mating together and the aluminum parts need a chance to expand, from the heat, fully. Riding before the engine is warm (and this reflects both the heat cycle routine and the controversial ride it hard off the floor) can cause the pistons and rings to sit prematurely causing wear and potential damage.

 

[crassius]

chinese pistons are unreliable - I've seen marks both ways on the 2-strokes and wouldn't trust them on 4-strokes either - I always check pin location on the 2s & check alignment marks & dipper on the 4s

 

[Riggsz]

I think the Chinese who are putting these engines together should lay off the Suki Yaki!

 

[butre]

I think the Chinese who are putting these engines together should lay off the Suki Yaki!

sukiyaki is delicious and not chinese, I think they're personally emptying every can used in the making of these engiens

 

[Fabian]

Idling a brand new motor is the worst thing you can do to it.
You want load on the rings and you want to rev it out to seat the rings right away.

I agree.
You definitely want to be reeving the engine to peak cylinder pressure, which is going to be somewhere around peak torque, to force the piston rings against the cylinder wall to ensure good mating between both surfaces.

I have never used manufacture recomended (gentle) break-in with any of my engines, be it car, motorbike, agricultural equipment or my motorised bicycle engine. Having said that, i do not abuse the engine, rather just operate it like i normally would, from the very word go, and they run just fine, and (on the dyno) they make more power than those who have followed the gentle break-in process.

I am pretty sure that the arrow is supposed to be facing the exhaust.

I agree.

 

[KCvale]

Just to be clear, the HS 142 engine is one thing, the 7G is another, this is an HS 142 engine problem not 7G as it has it's own faults.

The only issue I have had through a dozen 142's was the oil seal on one I tried to file down for a bearing clutch bell.

I do them all the same...
Fire it up, let it warm a couple of minutes, and then a ride around the block and back to the build bay to check everything.
The next ride is the hard ride, plenty of wide open with typical residential stops.
After our test miles, ~10 usually we change the oil.

HS 142 PERFORMANCE TIP: Get an NGK 7544 (VR7HIX) Iridium spark plug, we still can't believe the boost but standard in them all now here.