Hi all, great site you have here.
Just bought an '88 honda cbr 600 with 24,600 miles for $600. The bike is in great condition but it doesn't run. The previous owner said that it either had low, or no compression in one of the cylinders, he couldn't remember.

I haven't tried actually starting it yet, but I am wondering where to begin. I think I'm gonna do a compression test on each of the cylinders, and proceed from there. My first of many questions is, what is the best way to get at the spark plugs? Do I have to remove the radiator first? Or is there a special combination of wrenches that I'm supposed to use? Also, what size wrench do I need for the plugs? Thanks in advance.

 

the plug will take either a 13/16" or 21mm thin wall deep sparkplug socket. most normal sparkplug sockets are too thick to fit down inside the head. you will either have to buy the right one from the dealer or another store. or use a grinder and make your own thin wall socket shaving down the outside.
with a deep socket and short extension, you can easliy change sparkplugs without removing the radiator.

 

Thanks for the reply but after having no success with a 21mm socket, I ended up talking to a honda dealer and he told me that I would need an 18mm thin wall deep well socket. Turns out he was right. Thanks anyway.

 

The best way I have found to remove the plugs is to put the socket with a short extension down the hole in the head, then put the ratchet on the extension. Break the spark plug loose, take the ratchet out, pull the extension and socket out and then use a short length of 3/8" rubber hose (inserted into the plug hole and pushed over the insulator on the plug) to unscrew the plug and remove it. Reinstallation is reverse (use the hose to start the plug, then tighten with the ratchet). They are a tight fit to get to, but not impossible.

 

yes, that is the same procedure i do with the wrench. it doesn't fit in all at once. sorry about the wrong socket, i was going off the top of my head and forgot its the smaller size plug.