Topic: 1972 CB350K4 Twin Rebuild

[r6100mph]

So I picked up this beauty for $200 off craigslist.  Was sitting outside under a carport for 4-5 years.  Vines growing over the tires, hundreds of moths under the gas tank, and seat.  I figured if it didn't run, i was going to part it out, but got it home, threw a battery in it, some fuel, and fired right up.  Pretty rough running but hey, a whole motorcycle that runs for $200, not bad.


Shot with DSC-W1 at 2009-08-10

Shot with DSC-W1 at 2009-08-10

Shot with DSC-W1 at 2009-08-10

Shot with DSC-W1 at 2009-08-10

Shot with DSC-W1 at 2009-08-10

[r6100mph]

Starting to strip her down, and get cleaning.


Shot with DSC-W1 at 2009-08-10

The tank was an issue with the rust in the tank, used Muratic acid to clean the inside of the tank, but watch out this stuff will eat the skin off you arm, but a couple of minutes, full strength in the tank and it was pretty much spotless.  I made the mistake of using the petcock to keep the fluid in and it ate right through the aluminum, in seconds.  use a rubber stopper.  Sorry no pics of the cleaned tank.s




large dent right on top, where my paint and body guy, (my dad) filled in with bondo

[r6100mph]

Carbs:

[r6100mph]

Decided to strip completely down, re-paint everything





Sorry for the jump in pics, but in the midst of dis-assembly, I didn't take more pics.

The engine out of frame:

[r6100mph]

Pipes, before and after, they are in pretty good shape, expect for a few dings, and looks like some battery acid or something was spilling on the right side pipe, and ate into the chrome.





Rear fender, started with some naval jelly rust remover, not leaving it on too long, then wipe clean and rinse with water.  Then using some chrome polish, "blue magic" I think it was.  Works pretty good, even removes some of the surface rust.  Still some pitting but not too bad

[r6100mph]

Frame cleaned and painted with gloss black.  Triple trees cleaned and painted with satin, along with the bar clamps satin. 

Taking all the nuts and bolts and using a wire wheel grinder to clean them.  It's a softer brass wheel that doesn't leave deep scratches.  Many of the brass wire wheels I have, are far to stiff for cleaning. 

Installed new "superbike" bars which fits the bike really well, as far as look goes, and also pretty comfortable.  Gives you a more "aggressive" stance.

[r6100mph]

the rolling chassis:

[r6100mph]

Engine in, and all other stuff.  Another big jump in pics, but I was on a roll!





The Tank:


Mocked up with another 350 tank I have and the old seat:

[Zaipai]

Wow that is looking very slick.. For a $200.00 starting price you can't go wrong.. Nice work!

[r6100mph]

Wrapping up the rebuild.  Installed all new cables, Emgo air filters, no re-jetting required, just some fine tuning with air/fuel mixtures, and an eyeball synch with the dual cable carbs.  









just got the new seat cover installed today, and I'm waiting on the front brake cable.  I will post some final pics of the finished bike in a few days.

Runs great!  Top notch, pulls strong with no hesitation.  It did have a slight hesitation around 4000-7000 rpm, but I pulled the carbs again and soaked them in a carb cleaning bucket.  A blocked, secondary jet I believe, because now the hesitation is gone, and smooth from idle up to redline!  There is an oil leak out of the clutch pushrod, and shifter seal in the engine, but I plan to pull the engine, and re-build completely with new piston rings, light hone, clean valves, maybe re-paint engine.  

I haven't checked valve clearances yet, or checked timing, but they cant be too far off with the way it runs.  I plan on going through the engine, and doing all the maintenance stuff now the cosmetic stuff is done.  Stay posted on the engine rebuild, and I have another 1972 CB350K4 i'm going to re-build but completely stripped down cafe racer, minimal wiring, possibly a cafe style seat with the hump to house battery and rectifiers, etc.  I love that look where it's open frame where the battery should be.

[r6100mph]

Now that it's pretty much finished I will go through the "before" pics and mimic the shot for the after pics.

here's one:

[r6100mph]

Special thanks to my dad for being the cleaner, and painter!  Couldn't have done it without you!

[Zaipai]

Wow that is looking very nice. If you can get some video of it moving around when you are done that would be cool!

[r6100mph]

I will try to get some video, but I don't have a camcorder, just the small clips I can record with my camera.  I'll give it a shot!

[articblue]

Pretty awesome, and a good find at that.

[d3buttz]

looks good MAN!  lets go ride this weekend, the guys and i get together on sundays in the highlands.

[r6100mph]

I'll have to keep that in mind!  I still need to get it registered and insured so I can get it back on the road.  I hate dodging cops around town!

[r6100mph]

Some final pics with the new seat cover.  I still want to get rid of that tail light and maybe get some LED's to put on the rear fender bolts.  Would clean things up a lot!

Now on to the next one!

[r6100mph]

No tailight.  Any thoughts?  Leave it on or get rid of it?

[Zaipai]

Maybe put a low profile light with license plate bracket on it. It really depends on what your going for, it does seem to need some thing there. I never really cared much for the stock tail light.. too big and square.. I have to say that is ONE clean sharp looking bike, I would be proud to ride that around.. Awesome work.

[GoatBaSS]

It might look good with a 1950s car taillight. Working with the curve of the fender?

[strangedaze39]

I like GoatBaSS's idea.

Check this one out Ford Model A style:
http://cgi.ebay.com/ebaymotors/Chopper-bobber-model-A-tail-light-license-bracket_W0QQcmdZViewItemQQ_trksidZp3286Q2ec0Q2em14QQhashZitem5ad287ccfcQQitemZ390079171836QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessories#ht_500wt_1182

[luder]

Nice build and one sweet looking ride.....luder

[GoatBaSS]

I was thinking something in this arena.  

 www.nostalgic-products.com/ lighting.htm
The 39' might look cool close mounted to the fender. A few options to consider....

[r6100mph]

All great ideas, thanks for the input!  I'll have to do some photoshop work to see what options look the best.  I'll post the pics, if I ever get around to it