The bottom ends of these motors are good for pretty high mileages if the oil is changed regularly.
First thing is to check the compression (im betting its low) then
I would go for a full top end rebuild purely on how cheap these little twins are to rebuild.
Pull the top end which means you can check the big ends of the con rods for obvious play.
Get the barrels bored and honed to +.5mm.
Get some +.5mm pistons and rings (i have had pretty good success with cheap ebay pistons and genuine honda rings rebuilding a cb200 like this).
The cylinder head can then be rebuilt and with new valve stem oil seals.
Check the play in the valve guides and the cam journals for wear as these engines suffer from top end oil starvation. Fucked journals mean a second hand good condition head will be needed.
Grind the valves in.
Throw in a new cam chain and call it done.
All this is super cheap and should give you a good starting point.
The first thing before anything is to get the engine running properly So get that compression test done.
If by a miracle its good then you need to get a good spark from the ignition system (new coils, points and plugs will cost no more than £50 its almost rude not to) and a correctly metered fuel supply (clean & rebuild the carbs)
These bikes have such a huge amount of spares available they are a nice little cheap project to tinker with while drinking a couple of beers on a friday night.
Enjoy
First thing is to check the compression (im betting its low) then
I would go for a full top end rebuild purely on how cheap these little twins are to rebuild.
Pull the top end which means you can check the big ends of the con rods for obvious play.
Get the barrels bored and honed to +.5mm.
Get some +.5mm pistons and rings (i have had pretty good success with cheap ebay pistons and genuine honda rings rebuilding a cb200 like this).
The cylinder head can then be rebuilt and with new valve stem oil seals.
Check the play in the valve guides and the cam journals for wear as these engines suffer from top end oil starvation. Fucked journals mean a second hand good condition head will be needed.
Grind the valves in.
Throw in a new cam chain and call it done.
All this is super cheap and should give you a good starting point.
The first thing before anything is to get the engine running properly So get that compression test done.
If by a miracle its good then you need to get a good spark from the ignition system (new coils, points and plugs will cost no more than £50 its almost rude not to) and a correctly metered fuel supply (clean & rebuild the carbs)
These bikes have such a huge amount of spares available they are a nice little cheap project to tinker with while drinking a couple of beers on a friday night.
Enjoy