Rebuilding Chinese 2-stroke engine - photo tutorial

Not super pro but the step by step engine tear downs by Norm are good.
I am by no means a "PRO" or "EXPERT" on these little engines. Is there a proper procedure to breaking down and putting them back together? I'll do a seaarch and see if can find the post by Norm on this ! They are very simple though from my point of view.
Thanks !
 
Radial depth is the measurement from the top to the bottom of the ring.


Axial depth is the measurement from the outside to the inside.


Is the cylinder plated or just a high silica content aluminum alloy? Id be surprised, cause high silica aluminum is relatively expensive to produce.
 
Sorry !

I knew as soon as I did not take many photos, that later I'd wish I had. If I have to tear this engine down again, I'll definitly take photos. Since I put it back together I've installed a pull starter and a centrifugal clutch on it as well. I just need to find a bike to put it on and get it running and tweaked.
Sorry guys. I'll try to do better next time. Also, if someone finds another thread/post about tearing them down and putting them back together, please post. Maybe the one Pablo posted here about Norm might be one. Fabian, you think if we can find a way to utilize that "D" cell that we might be able to gain a little extra power out of these things ?
Thanks !

..... PC .....
 
Radial depth is the measurement from the top to the bottom of the ring.


Axial depth is the measurement from the outside to the inside.


Is the cylinder plated or just a high silica content aluminum alloy? Id be surprised, cause high silica aluminum is relatively expensive to produce.
I want to make sure I uinderstand correctly. The ring has width and depth or thickness. Is radial the same thing as width. It has nothing to do with diameter, right ? Let me know ASAP. I'm going to the garage right now to get a ring and my michrometer !
 
lol. yes just check the ring flat. Top to bottom.

Since you're a newbie, do you know how to do Private Messaging. No, I don't think you're dummy. I know I had problems at first and others have too. Heck, I'd been a member for a month or so before I even knew about it !!!
 
lol unfortunately i am a forum *****... as much as I hate to admit that.

PM me on "forum *****". I don't kniow what that means. Also, let's try to stay on subject here. This thread belongs to someone else. Some don't like it at all when you take over their thread. I respect them. I've had it done to me before. PM anything !
 
Hi Porkchop

I am already in the process of design and then construction of a 350 to 500 watt dc generator that doubles as an electric starter motor and auxillary 350 to 500 power assist fed back through the SickBikeParts Jackshaft, shifter (shift) kit to the Chinese motorised bicycle motor.

My initial goal was to have enough power generation capacity for two 100 watt automotive style driving lights with enough reserve power to run 3 sets of automotive indicator lights and two automotive style brake light sets.

A side goal was to be able to charge a 12 volt 7 amp hour battery to give short bursts of power to the dc motor/generator, allowing 350 to 500 watts of auxillary power to be fed into the Jackshaft system for emergency overtaking maneuvers of pedal powered cyclists in their expensive lycra bike shorts riding their excessively expensive road racing bicycles, holding up the freight train that is me towing a gross weight of 60 kilos with my trailer and payload combination :)

Fabian
 
Radial depth is the measurement from the top to the bottom of the ring.


Axial depth is the measurement from the outside to the inside.


Is the cylinder plated or just a high silica content aluminum alloy? Id be surprised, cause high silica aluminum is relatively expensive to produce.
O.K. Here's what I'm getting 1.97mm for the radial (top to bottom) and 1.87mm for axial (width). I can't tell you anything about the cylinder other than is does not have a liner. I can just say the engine is a Grubee 50cc Starfire Gen. II, manufactured in January 2009. Hope this helps.
 
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