Breaking engine cases: Zongshen / CSC TT250 / Bashan 'Xplod' CG 230 balance shaft

tonyscott123 · 10-17-2017, 05:11 AM

The kick start system on my bike has given up the ghost, and I have to get into the motor to strip it out.

I have taken off the RH engine cover, stripped off the centrifugal oil 'filter' and the clutch.

Now i am trying to get the rest off (refer to the attached picture so kindly supplied by CSC). I need to get off the balancer gear on the RH (front) of the motor, and the crank gears, before splitting the cases.

No matter what I do with the limited tools available, I can't move the castle nut on the counter balancer (I believe it is a left hand thread) even with a heat gun applied.
How do I get this off? Also, how do I get the rest of the crank gears off?

And last question, any guidelines for removing the cylinder head and barrel?

Any further tips to splitting the case?

Thanks

Tony Shelver

wamey · 10-17-2017, 05:49 PM

Universal socket:
http://a.co/caCK5HQ

and an impact wrench, keep the bike in gear and tension on the system in one direction or the other so it doesn't shake too much

Ariel Red Hunter · 10-17-2017, 06:53 PM

Quote:

Originally Posted by tonyscott123

The kick start system on my bike has given up the ghost, and I have to get into the motor to strip it out.

I have taken off the RH engine cover, stripped off the centrifugal oil 'filter' and the clutch.

Now i am trying to get the rest off (refer to the attached picture so kindly supplied by CSC). I need to get off the balancer gear on the RH (front) of the motor, and the crank gears, before splitting the cases.

No matter what I do with the limited tools available, I can't move the castle nut on the counter balancer (I believe it is a left hand thread) even with a heat gun applied.
How do I get this off? Also, how do I get the rest of the crank gears off?

And last question, any guidelines for removing the cylinder head and barrel?

Any further tips to splitting the case?

Thanks

Tony Shelver

On removing the head and the barrel, taking the head off is pretty obvious, after you take the valve cover off. But be careful when you pull the barrel. I used to use two notched pieces of wood to hold the rod and piston straight up when removing the barrel. That's how you avoid denting the piston and the crankcase mouth...ARH

tonyscott123 · 10-18-2017, 02:17 AM

I don't need the universal socket, I bought the special castle nut tool which is also used for the centrifugal oil filter castle nut. The universal sockets are usually too big to fit inside there.

Now to see if I can borrow an impact wrench somewhere.

Cylinder head came off fairly easily once I got a 1/2 drive 12mm socket (the smaller drive socket head twisted off)....

wamey · 10-18-2017, 09:50 AM

Quote:

Originally Posted by tonyscott123

I don't need the universal socket, I bought the special castle nut tool which is also used for the centrifugal oil filter castle nut. The universal sockets are usually too big to fit inside there.

Now to see if I can borrow an impact wrench somewhere.

Cylinder head came off fairly easily once I got a 1/2 drive 12mm socket (the smaller drive socket head twisted off)....

Another thing to watch out for, see if you can see which way the thread is going on the shaft (LH or RH), I don't know which way these go, but you never want to tighten this stuff down with an impact wrench.

tonyscott123 · 10-31-2017, 01:09 PM

Got the motor apart some while ago (dealer did the final few bolts as i didn't have an impact wrench).

Beginning to think I need to replace the whole motor.... What alternatives? In the Philippines I had a Zongshen with a 200cc 'CBB' (Honda CB design with balance shaft) that was lighter on fuel and faster than the Bashan '250'. And as it turns out, more durable.
How difficult to fit one of these?

Original problem was a totally destroyed transmission shaft bearing, with metal all over the motor.

Seems that both transmission shafts, the bearing and maybe the LH crankcase need replacing. Add in the various gaskets.
I got the LH crankcase back to get a machine shop quote to repair, and notice tha a few of the bearings have metal gunk in them, and can lock up under finger pressure.

Now I am concerned that all bearings need to be replaced, maybe even crankshaft. Also could have affected the top end to some degree, although i couldn't see anything at a glance.

10-17-2017, 05:49 PM	#2
wamey Join Date: Jun 2017 Location: Madison, WI Posts: 96	Universal socket: http://a.co/caCK5HQ and an impact wrench, keep the bike in gear and tension on the system in one direction or the other so it doesn't shake too much
	0

10-18-2017, 02:17 AM	#4
tonyscott123 Join Date: Nov 2011 Posts: 22	I don't need the universal socket, I bought the special castle nut tool which is also used for the centrifugal oil filter castle nut. The universal sockets are usually too big to fit inside there. Now to see if I can borrow an impact wrench somewhere. Cylinder head came off fairly easily once I got a 1/2 drive 12mm socket (the smaller drive socket head twisted off)....
	0

10-31-2017, 01:09 PM	#6
tonyscott123 Join Date: Nov 2011 Posts: 22	Got the motor apart some while ago (dealer did the final few bolts as i didn't have an impact wrench). Beginning to think I need to replace the whole motor.... What alternatives? In the Philippines I had a Zongshen with a 200cc 'CBB' (Honda CB design with balance shaft) that was lighter on fuel and faster than the Bashan '250'. And as it turns out, more durable. How difficult to fit one of these? Original problem was a totally destroyed transmission shaft bearing, with metal all over the motor. Seems that both transmission shafts, the bearing and maybe the LH crankcase need replacing. Add in the various gaskets. I got the LH crankcase back to get a machine shop quote to repair, and notice tha a few of the bearings have metal gunk in them, and can lock up under finger pressure. Now I am concerned that all bearings need to be replaced, maybe even crankshaft. Also could have affected the top end to some degree, although i couldn't see anything at a glance.
	0