Cafe racer stylings.

Here's a great CB360 cafe racer site, Motofiaccone.  Please mind the scantily clad young lassies.  There is some decent info on tank construction, seat fabrication, painting, and various other cafe racer minded strip downs.  Sometimes, I wonder how anyone has time to do all of these things.  Really. How?

Putting it all back together...

So, the pistons have been removed and I have a ton of parts to choose from.

I ordered new rings but only have used pistons and cylinders. By fitting all of the pistons into the cylinders I get the ones that are tightest and with the least damage.

Note the scratches and lovely cam chain damage in these pictures.

I pick my pistons and am very careful putting on the new rings so I don't scratch the piston or break that long awaited new ring. There is nothing more frustrating, believe me. Well, dropping the circlip from the piston pin into the bottom casing--that makes you cry. Or maybe when you get the whole bike back together and then you hop on and crank the kickstarter only to have it clink across the garage floor--no, it didn't just come off, the whole damn arm snapped--that's frustrating.

With the newly added rings, I oil up the inside of the cylinders and head back out to the garage and do it all in reverse. Please, make sure to put a towel under the piston when putting the pin and clip back in, you don't want to have to take apart the bottom end if you don't have to. Also, note that the arrow on the piston should be pointing toward the exhaust when reinstalled.




Once the pins and clips are in place, slip the cylinders down over the pistons. You may have to work the rings into the more confined space. A rubber mallet would certainly come in handy.



Once you have everything lined up, push the cylinder body all the way down and take a good look at what you just did.



Now, put the rest of it back together. Beginning to end, I'd give this 8-10 hours depending on your skill with tools, your work space, how much beer you drink, and your smoking habits.

Top-end tear down

Here's a real quick run through of tearing down an engine to the pistons. Note, that this may all be done on the bike without having to remove the engine from the frame.

(the bike before any work)

First, remove the seat, gas tank, and battery. Next, remove both exhaust pipes and mufflers. It wouldn't be a bad idea to loosen the battery box at this time to ease removal of the carburetors.

(to remove the seat pull the pin connecting it to the hinge)

To remove the gas tank, turn the petcock to stop. Then, remove the gas lines connecting the tank to the carburetors at the petcock. Pull the tank forward and out of the rubber mounting piece. Lastly, pull back on the tank and it off of the bike. Make sure to not snag any of the electrical harness in the process.

(remove the lines at this connection--it really doesn't matter, but they are easier to reach in my opinion. Note: I have used clear solvent resistant tubing for my gas line. This enables me to check float bowl levels on the carburetors and to quickly assess any issues with gas flow while tuning.)


(This is the tank pulled out of the rubber mounting. Do take caution to not tear the rubber mount--they can become fragile after 30 some years)

(after removing the battery, loosen/take out three bolts holding it to the frame)

Next, remove the exhaust pipes from the engine block and the frame. To do this, loosen the nuts nearest the header pipes and engine. Then, loosen the nuts holding the muffler and the passenger foot pegs to the frame. The pipes should come off as one piece. Make sure to not lose any exhaust gaskets or nuts. The right side pipe is a bit more difficult to work out due to the foot brake, but with a little maneuvering and care to not scratch the chrome, it finds its way out.

(This is the bike at this point--notice, I have removed the starter motor on a previous tear down)

(This is a close up, obviously perhaps)

So, now we start tearing into the engine. First things first, remove the carburetors at this point. In my ever so informative sequential pictures, I did not do this. So, this goes to show that there are multiple ways about this. At some point, ie when you are going to remove the valves, the carburetors have to come off. So, one may choose whenever they feel ready.

Start by removing the points cover. This is the grooved black casing found above the spark plug (left side of the bike).

Once this has been taken off (save the paper gasket) follow the wires to the harness. This is where the breaker points connect to the coils. A short description of how this works is the cam chain is turned by the crankshaft and in turn rotates the oblong cam triggering a spark advancing mechanism. This is fancy for a spring loaded switch that opens and closes the points which control when the coils fire the spark plugs and thus combust gas in the cylinder chamber. You can visualize the feedback loop of this all because when the gas combusts it depresses the piston and turns the cam chain...a lovely little closed loop of controlled explosion.

(connected)


(disconnected)

Now, we want to remove the breaker points and entire timing mechanism. I have provided some pictures again. Unscrew the two larger screws holding the plate to the bike. Next, loosen the bolt on the cam--you may have to click the bike into gear to give you some resistance.

(notice the two larger phillips head screws on the edge of the circular plate)


(remove the bolt at the center of the cam--put it back into the cam chain once the spark advance mechanism has been removed so as to not lose it)

Okay, so the timing has been taken apart. We can now remove the breather cover (picture shows this all ready taken off). The two plates also need to be removed that attache the top part of the engine to the frame. Again, the picture shows them dismantled.

(check out the sweet gold tappets--I'll put the link up to them soon. They are made in South Africa and run about 8 a piece)

Once the breather cover has been removed, move on to the valve cover. Should be about fourteen bolts total. Eight large and 6 small. Make sure you have a nice ratchet set or you aren't going to get much past this point.

The cam chain is still attached at this point. To take off, loosen/remove bolt (on the wheel chain raps around) and advance the engine half turn (done by removing the stator cover and advancing the alternator). Remove the second bolt. This takes a bit of working, but you can wiggle the cam through the cam chain and get it off of the bike. Accomplishing such a feet requires taking out the cam chain tensioners as to acquire ample slack for said wiggling. Note there are two tensioners, one at the dorsal and ventral of the cam chain. Remove both of these prior to removing the cam. Also, be very very careful not to drop anything into the engine as this will require a full bottom end tear down to remove schwag. Not fun unless you have to--also not that hard, so if you feel like learning a bit more, cluts it up.

If you are going to tear the engine down farther, you need not concern yourself with holding the cam chain in place. I should mention that the reason for my tearing the engine down was a cracked oil ring. I was burning a whole lot of oil and then the engine froze up upon kickstarting one day...so...I am not expecting any major damage or permanent freeze, but new rings are at the very least in need.

Remove the carburetors.

(you must remove the airboxes prior)

Removing the carburetors is a bit more complicated than simply taking them off. You need to disconnect the throttle cable from them to take them completely off of the bike. Of course, to just tear down the engine you could disconnect them from the manifold and leave it at that. But, if you are going this far, a quick carburetor clean-up and check-up might as well be in order. So, disconnect the carburetors from the manifold and pull out of the frame as far as possible. Disconnect the throttle cable at the carburetor (not at the handle bars like some manuals suggest). I will leave the fun of figuring this out for yourself. It is simple, just keep your patience.

Once the carburetors are off, remove the valves and subsequently the cylinder block. With all procedures, no heavy forcing and/or prying should be used. Usually a few taps with a rubber mallet is all that is needed. And make sure all nuts and bolts are loosened before prying with screwdrivers and pry bars.

And that is that. I am still waiting on my new rings. I have some extra pistons and cylinders so I am trying different pairings to see which has the snuggist fit. The compression was about 145 before disassembly, so not much to really be worried about. Write with any questions: uberdoom@gmail.com . More posts on bike in the future.

Over the winter I will be turning it into a cafe racer--painting, cleaning, cutting, chopping, polishing, tuning, etc...