Project Atlas - '69 CB350

this engine was recently "serviced" although I think they did the bare minimum of trying to hone the cylinders and call it good - the timing tensioner is seized and I'm guessing that resulted in THIS:

ignition timing was 90* off and that's probably why the bike was parked.
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every. single. JIS screw. was. stripped!

I have some sympathy... I am, after all, working on the patio in my back yard (no garage here!)
but hey... do it right may take some time like my last build. the end result will be worth it
I'm always surprised by the number of "mechanics" and engineers that don't know about JIS. But then, I only learned about ten years ago. In my defense, our machines had maybe three metric fasteners. All the rest still ASE.
I've checked out the cam, it seams servicable
"fat cam" with 36.xx MM largest diameter on the lobes.
I THINK, this is the desirable "early" fat cam? (tach is the 10.5k redline version)

I was busy putting rockers/shafts in the appropriate bags to keep them together I have not yet inspected them for wear. I wonder if they can be resurfaced without hurting the performance aspect of the cam

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working a little bit with the parts washer and got the parts looking much better!

will likely be blasting the barrels and sending the rest of to vapor blast. who knows

was able to acquire a second cam on ebay - mine was marginally worn


original cam on left - "new" cam on right.


the original cam has this groove and the numbers 10/3/1 on it ** the "new" cam has no groove and marked 6/6/1
both have the same measurements but the new cam is in much better condition

now I just need to find some NOS pistons that are oversized. (the bore is... well it's OK but I'm concerned about the markings on the pistons themselves)
Today I've taken apart the CL450 forks.
They are external spring forks and I am exploring lowering them.
Removing the internal damping rod was a pain, but I wanted to see how these forks worked, to ensure they can be "safely" lowered internally... I do believe I can make a spacer for them, where they can be lowered up to 3 inches (I won't be lowering them that much I don't think... maybe 2"
I'll also be removing the fender mount bosses and cleaning up the forks some. Yes I do realize that is detrimental to performance - this is nothing more than a "will be ridden to the local bike gathering spots" build and hopefully another 1moto/handbuilt invite.

Monday is shop day around here - Most of the engine parts are on their way to be vapor blasted. I've begun working on the internals of the forks to lower them "safely" and it's been pretty boring around here without much to do. So I've got a couple of concepts to work out. Any votes on who likes what? (after falling in love with the hard tail, I am now very much enamored with the mistress bobber)

spent about 4 hours today on the top and bottom triple getting them cleaned up

SL350 top and bottoms so I can use the 35mm black bomber forks



I also cut off the steering lock cylinder and plan to use the mount as a headlight mount. There was no real easy way to remove the bosses on the lower triple without revealing my methods so... they will have to be used for SOMETHING just not sure what. I also have to figure out a method to attach the handbar under and in front of the top triple...


overall I am happy with how well these are turning out - still got some final touches to make before they are perfect.
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Looks good. My first build was a 71, and put your tank on. What are you planning to do with your original tank?

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The original tank had some JB weld epoxy on the seams - I am pretty sure it's junk, it has a small dent in the top rear so I may just hang it from the rafters.

I have a plan to cap these forks off that might make people never want to consider wearing an open faced helmet again.


also, the handlebars will be mounted UNDER and FORWARD of the top clamp - using some brackets I am making:

found these nifty allen plugs - the top bolt for these external spring forks are too tall, meant to secure the top clamp in place above the fork. They are also 16x1.50 thread if anyone needs to know - same size as a BMW engine oil drain plug - so these types of bolts in all sorts of fancy ends are available cheaply.


still gonna have to clean up the top of the fork there... and I still have a plan to make it look more.... diabolical :eek:
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