Story of two boys a world away

[allen standley]

Example of how a person can be discouraged from these No Quality Control 2cycle motors.
From my local junker guy I purchased a milk crate with 4 parted out motors, 2 - 48s and 2 - 66/80s. Plenty of spare parts which made the $20 purchase a bargain.
As i was going through, I picked up a 66 which actually looked as if it were never run. I pulled the head and there was no typical carbon buildup nor fuel stain on the piston…looked new!
This motor (although I have no idea of the history) was painted black @ factory and was in fact complete except no clutch cover and missing a couple pucks.
I pulled the cylinder and immediately discovered why it was junked.
Same old story played out in my mind. Goes like this or similar.
13 year old kid mows lawns, works at the golf course caddying, works all summer long to buy an engine kit to put on his bike. Finally earns enough money to order his Amazon / ebay motor kit. It arrives several days later and he's so excited to do a good install so as to ride and enjoy. He has a mechanically inclined Dad or Uncle to help with the install and everything assembles as it should. The moment of truth comes so he hops on and pedals up to a speed, pops clutch BDDDDDH. No start- he tries again- BDDDDDH, Pop Pop. He tries again BDDPOPPOPPOPPOPBDDH.
This repeats a couple more times and the motor starts, then quits and never starts again. OR, the motor starts it runs! he motors down the road but the motor doesn't seem to accelerate. No power - No umph - then motor stalls. No matter what Dad tries to trouble shoot nothing fixes. Bike is parked and the quality and reputation of these motors continue to reflect on the 13 year old chinese boy sitting on a concrete factory floor, barefoot, next to a wooden box of motor parts all willy nilly.

My point? Sometimes, more often than not you DO NOT GET What you pay for.
So is life.

I Advise buy from somebody you can talk to.

Here's the problem with this once New motor. As we can see Cyl. plating was spalling off the very day it was assembled.

 

[indian22]

Great insight Allen.

Rick C.

 

[lewdog7431]

My question would be ,i can see how the plating has been removed and the under metal is showing probably raw aluminum does that actual plating make a difference with the piston and the rings passing through that threshold of missing material ,the rings are going up n down so fast and the tollarance should be +or= what for a ring to slide evenly throughout the stroke before what breaking and seizing and or allowing gasses to escape through the chamber to cause low compression whitch means low power ? ? ?

 

[allen standley]

Nobody can see how the plating was removed. The plating was never removed, It is poor plating due to improper conditions during the process of plating. No quality control -a situation where every cylinder cast is counted as a sale. Nobody in a communist country dares to stop a production line------SEND IT THROUGH or be a problem. do you understand?
Did you read the post from the start? The pic speaks for itself- does it not? Would you install that? The engine this was removed from NEVER started.

 

[indian22]

Chrome plating makes all the difference. It completes the seal with the steel piston rings & keeps pressure levels where they should be. Loss of seal pressure means engine won't run. The chrome is hard and durable, the aluminum of the jug is soft and the steel rings would ream the cylinder walls in just a few rotations without the chrome protecting it..

Back in the fifties and sixties the air cooled 2 cycle engines had steel liners that worked well for wear, durability and were long lasting, but held too much heat and eventually the piston would seize and a new engine top end replacement was required. The explanation for this is that steel and aluminum expand under heat at different rates and seizing occurs. Often even the lower rod bearing was fried trying to keep up with the ever increasing forces of friction.. Four cycle engines are much more forgiving in this area of liners and can be bored out and oversized piston installed when cylinder bore wear occurs. This can't be done with chrome liners, these must be replaced.

It's a major mistake to think two stroke and 4 strokes engines have much in common. They don't!

Chrome plating the cylinder bore of air cooled 2 cycle engines solved the seizing problem, but here's where Allen's post is dead on correct...bad chrome plating quality on cylinder bores is much worse than using the the old cast iron liners on 2 strokes. They would at least run until the piston seized under hard running. Two cycle race engines were notorious for seizing during those mid century contests and the Japanese manufacturers quickly turned to high quality chrome bores to fix the seizing problem and today most high quality two stroke motor cycle engines typically run chrome bores, though some use exotic materials like ceramics etc.

Good chrome plating is just that...good. I've run China girl kit motors for over a decade and not had a single problem with plating until the last two years. I had two back to back engines sent out with bad chrome liners. Two different motor brand and two different distributors, that I've purchased from in the past with no problems. I had spare jugs on hand from old engines past and I just put these on and the bikes are running fine now.

I'm holding on to my old cylinders until China gets this problem fixed. The old chrome was so good I was able to carefully port and even machine third transfer ports without chrome flaking off the edges let alone spalling. In my opinion the problem is a lack of quality control.

Rick C.

 

[allen standley]

 

[allen standley]

Chrome plating makes all the difference. It completes the seal with the steel piston rings & keeps pressure levels where they should be. Loss of seal pressure means engine won't run. The chrome is hard and durable, the aluminum of the jug is soft and the steel rings would ream the cylinder walls in just a few rotations without the chrome protecting it..

Back in the fifties and sixties the air cooled 2 cycle engines had steel liners that worked well for wear, durability and were long lasting, but held too much heat and eventually the piston would seize and a new engine top end replacement was required. The explanation for this is that steel and aluminum expand under heat at different rates and seizing occurs. Often even the lower rod bearing was fried trying to keep up with the ever increasing forces of friction.. Four cycle engines are much more forgiving in this area of liners and can be bored out and oversized piston installed when cylinder bore wear occurs. This can't be done with chrome liners, these must be replaced.

It's a major mistake to think two stroke and 4 strokes engines have much in common. They don't!

Chrome plating the cylinder bore of air cooled 2 cycle engines solved the seizing problem, but here's where Allen's post is dead on correct...bad chrome plating quality on cylinder bores is much worse than using the the old cast iron liners on 2 strokes. They would at least run until the piston seized under hard running. Two cycle race engines were notorious for seizing during those mid century contests and the Japanese manufacturers quickly turned to high quality chrome bores to fix the seizing problem and today most high quality two stroke motor cycle engines typically run chrome bores, though some use exotic materials like ceramics etc.

Good chrome plating is just that...good. I've run China girl kit motors for over a decade and not had a single problem with plating until the last two years. I had two back to back engines sent out with bad chrome liners. Two different motor brand and two different distributors, that I've purchased from in the past with no problems. I had spare jugs on hand from old engines past and I just put these on and the bikes are running fine now.

I'm holding on to my old cylinders until China gets this problem fixed. The old chrome was so good I was able to carefully port and even machine third transfer ports without chrome flaking off the edges let alone spalling. In my opinion the problem is a lack of quality control.

Rick C.

Thanks so much Rick, I am learning Lots from you. I appreciate the back story. I appreciate even more knowing you know so much more than I, and you are openly willing to take the time as you do to share with us all.

 

[indian22]

Thanks so much Rick, I am learning Lots from you. I appreciate the back story. I appreciate even more knowing you know so much more than I, and you are openly willing to take the time as you do to share with us all.

Thanks Allen. I don't know how much I know but I grew up with men who knew a lot and encouraged kids to try stuff and told stories about the old guys that mentored them (they would have hated that term applied to them). One of the guys was Alf Francis who was the head, mechanical Fred of formula one racer & world champ Sterling Moss. He also was well acquainted with John Surtees, who was a world champ on bikes before becoming one driving formula one cars. Alf introduced me to Surtees' books concerning 2 stroke design theory & that got me interested in ring dings and I campaigned a series of various size Bultacos as rider, crew chief, sponser & mechanic; I was no more than mediocre at each but had fun doing it. Along the way I learned from others, but probably forgot most of my instruction, except that which drew blood or broke bone.

Rick C.

 

[indian22]

Allen this is similar to very low U.S. tech circa 1907 moto bike assembly and testing.

Rick C.

 

[lewdog7431]

Thanks also rick fpr the enlightment and the discription of the jug plating and how it goes down, thank you