Chinese cylinder wall differences

B

Bubba-1

New Member
What are the differences in the cylinder walls between the 49cc & 66cc engines? I thought that I had read somewhere that the 49cc motors have a steel liner while the 66cc motors did not.

Could somebody please enlighten me.
 
As far as I know, it depends on the company you bought the HT from and if they make them well. Like my RAW 80 is perfect. The plating is great, walls are smooth, etc.

My friends GRUBEE 80 is ****. The plating is chipping off and he will soon need a new top end. We both ran the same oil and ratio, along with the same tuning. Just order from RAW, they are the best!
 
You can go up to 130cc in Wisconsin, as long as it has functional pedals.

340.01(29m)
("Moped" means any of the following motor vehicles capable of speeds of not more than 30 miles per hour with a 150-pound rider on a dry, level, hard surface with no wind, excluding a tractor, a power source as an integral part of the vehicle and a seat for the operator:
340.01(29m)(a)
A bicycle-type vehicle with fully operative pedals for propulsion by human power and an engine certified by the manufacturer at not more than 130 cubic centimeters or an equivalent power unit.

If you'd like, here's 2 PDF documents stating the relevant law info regarding motor-bicycles for Wisconsin. They are business card size if you'd like to print them.
cnetsystem.com/misc/bike/Wisconsin_Moped_1.pdf
cnetsystem.com/misc/bike/Wisconsin_Moped_1.pdf
 
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Thanks Pilotgeek. I missed that part. I was thinking the smaller motor for other reasons too though. Like the crankshaft balance, smoother running and longer lasting. I also thought that I had read somewhere about steel cylinder sleeves in the smaller ones. I can't find that reference now of course though.
 
The 49cc's do indeed seem a bit smoother/ rev out a bit higher. My 66cc's chrome bore has had no problems after about 700 miles. I have heard some stories about steel sleeves being put in crooked though.
 
anythinf from the chineese factories can be put in crooked. they have NO quality control
during assembly
the first time you start it is the first time it has been started
i have received motors with NO clutch bearings, cracked block on one, 1 blew the head gasket on the first startup on one.... head bolts were finger loose....lol, i had one they never removed the casting seams in the jug and several other major issues.
you take a chance on every motor being either great, fair for a while and some are trash right out of the box. most are fair or better
but the price is right to replace the motor

stay dry
gubba
 
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Pilotgeek said:
The 49cc's do indeed seem a bit smoother/ rev out a bit higher. My 66cc's chrome bore has had no problems after about 700 miles. I have heard some stories about steel sleeves being put in crooked though.
Click to expand...

the 50's are smoother because the 80's are just 50's with a bigger piston's the crankshaft isnt properly ballanced for the larger piston
 
It's more from a repair standpoint. As in if the motor gets a lot of miles on it and the rings and cylinder get worn but no other damage, a steel lined cylinder can be honed where as an aluminum cylinder cannot.
 
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