Fixing The Chain Tool And The Seized Motor’s Cylinder Head Comes Off At Last!

A couple of weeks ago, I followed up the chain replacement with some maintenance on my chain tool.

The 520 pitch pin for the chain tool didn’t fare very well after riveting the new chain and burred over again, so I had left it in the vice ready to tidy up with my handheld rotary tool.

Returning to the chain breaker/riveting tool, a couple of days later, I found I was unable to remove the 520 pitch pin from the collar as it had burred over.

Some work with the rotary tool took care of that and I was able to remove the collar and retrieve the spring.

I put the 50 pitch pin and collar back in the chain tool kit and checked the smallest pin. It turned out to be just the right size for the cam chain pins on the seized CB250RS motor.

I assembled the pin with the spring and the matching collar.

I fitted the chain tool onto the cam chain and tightened it.

After a few minutes I was able to break the cam chain.

I packed away the chain tool in its box. I’ll need a new chain tool before attempting any further breaking or riveting of 520 pitch chains!

With the cam chain no longer in the way, I was finally able to remove the camshaft and cam gear.


Next I loosened the cylinder head mounting bolts.

Then I realsied I hadn’t removed the cam chain tensioner bolts, so the mounting bolts for it came off next. I still wasn’t able to remove the cam chain tensioner though, as the cam chain was still in the engine.

I removed the lower engine bracket next.


The cylinder head nuts were the last thing holing the cylinder head down.

Finally, the cylinder head was off!

The cam chain guide came out very easily, but I still wasn’t able to remove the cam chain tensioner.



While the cylinder head gasket was in reasonable shape, the valves looked like they could use a good clean!

I disassembled the cam shaft, then packed and labelled the small parts to make finding them easier when the time comes for reassembly.

While putting the motor back on the bench, I managed to knock over the pegboard and with it all the tools that were neatly hung up!

I spent a few minutes replacing the hooks and setting the tools up in a way that will work for me later.

Finally, I updated the lists for the seized engine and called it a day.

The next update will most likely be more disassembly of the spare engine, although I may find some time to work on Sylvie as well!

That’s all for now, the next update will most likely be more engine teardown, although I may fit some more work on Sylvie in at some stage…