1970 CB350K2 Cafe Build "AK47.1"

Hi All,
I have been lurking the forum for quite some time while I dreamed of someday starting a cafe project of my own. Two weeks ago while surfing craigslist at 0300 in the morning I found this little gem:



Ok, so its not a perfect gem but the price was right, it wasn't seized and there isn't a ton of rust. The shift lever was broken, it was missing the kick start. The tank was empty and rust free and the engine had fresh, clean oil in it. I picked it up the next morning and the multi step process has begun. My plan is to get it cleaned up and running in stock configuration for this riding season. I have a 2008 Kawasaki EX250 that is pretty much my daily rider in the summer, so I don't "need" another runner, but my wife would like to learn to ride as well. Once I am sure that the bike is in good enough shape to warrant the money spent to cafe it the process will start all over again next winter.

Here are a couple more shots:

I built a work surface to bring the bike up to a more appropriate working height.


Then I began the rip and tear to get down to a roller that I could take to the car wash and clean up.


And so begins another "Big Arse Project."

Re: 1970 CB350K2 Cafe Build

Ok, I started polishing up the chrome on the mufflers and exhaust pipes, here are a couple shots to show the results.

Side by side shot of one polished and one as received:


Side by side shot of both polished up and looking good:


There is still some patina on the mufflers, but I like them that way. Afterall, this isn't a new bike.

I am having trouble sourcing an exhaust collar for one of the headers. The exhaust was off the bike when I got it and one of the collars was missing. I have done a lot of searching with no luck. The part in question is #2 in the below diagram. Anybody have any ideas to source one, new or used? The only place I have seen them is ebay and people want 40-50 bucks for them.

Re: 1970 CB350K2 Cafe Build

if you can't find them on ebay for cheaper than that, might have to go to a junkyard or even machine your own. Good work on polishing that chrome, but can you make the pics bigger?

Re: 1970 CB350K2 Cafe Build

really 40 50 bucks for exhaust collars where you at Hawaii. I wonder if the Kawi ones are the same. if you can get me some measurements i can try and find mine and compare them. they look similar. And thats a nice bike to start with. what plans do you have for her? keep it up.

Re: 1970 CB350K2 Cafe Build

By request, the pictures have been enlarged. Forgive me as I have never posted pictures to a forum before so I am not sure what size is most appropriate.

Thompson, I will get some measurements tomorrow and post them up. As for my current plans, I just want to get the bike cleaned up and in running order. Once that has been accomplished I will begin transforming it into a cafe. I really like the look of drag bars on the 350, but I may still go clip ons. Not sure about the seat yet as I would like to relocate the battery under the seat to clean it up a bit. I really like some of the fiberglass production seats available, but so many guys on here have built some amazing things by hand as well. I may go that route myself. As for paint, I have a scheme in mind, but the original paint on the tank is in great shape, so I may have to source another tank to paint so I can leave the stock one in original state.

Looking forward to sharing the build with everybody on this site, you all do some amazing work!

Re: 1970 CB350K2 Cafe Build

Just a quick update as work has been extremely busy lately and has been getting in the way. I will have a nice long weekend this week so there will be some progress.

I was able to finally find an exhaust collar on ebay for the right price, and it is on its way. I also have new exhaust gaskets ready to go when everything gets here. The rear wheel and fender came off today for clean up and I started cleaning up the engine cases, I won't be going to crazy with the cleaning and polishing in Stage 1 as I will do a complete tear down next winter as part of Stage 2. For now a simple cleaning and light polish will be fine.

I promise more pictures this weekend, I will have a lot of time to get things done.

Re: 1970 CB350K2 Cafe Build

Ok, so the pictures are a little late. My weekend was interrupted by some household items that needed tending to in order to keep the SO happy. A few quick updates for tonight. I was able to finally track down the exhaust collar through a honda dealer, so that is on its way. I began tearing apart one of the carbs today for cleaning and stumbled across this unfortunate issue:

It may be a little hard to see, but the carb diaphram has a pretty healthy crack in one spot and a pinhole in another. From what I have found, these diaphrams are no longer available so I have two options, first is to send it away for a custom diaphram and the other is to attempt a patch. I believe I will opt for the patch at this time, has anybody tried patching a diaphram before? Success? Failure? Linky?

This picture I just thought was cool.

Starting on Friday I will have a whole 7 days off so here is my To Do List:

Clean carbs and reassemble.
Clean engine and return to frame.
Finish polishing rims and return to bike.
Install new points and verify timing and ignition.
Install battery and attempt to fire.

Long list, but I have a lot of time to work on it so we will see how far I get.

Re: 1970 CB350K2 Cafe Build

http://www.siriusconinc.com/pro-detail.php?pid=&product_id=1503

Re: 1970 CB350K2 Cafe Build

danfr said:

http://www.siriusconinc.com/pro-detail.php?pid=&product_id=1503

Click to expand...

Thanks for that link danfr, a little more than I want to spend, but I might have to bite the bullet on that one. I attempted a patch, we will see how that goes.

The good news is that some work has been done and the engine is running.

I did a little more polishing on a few items, here's a shot of the rear brake hub in progress.

Unfortunately I got busy and forgot to take a picture once I was finished.

I also got the rear wheel cleaned up a bit and it is looking pretty good, with the exception of the spokes, I didn't do much to them. When I do the complete tear-down next winter I will get it spic and span, for now this is good enough.


Here is a good shot of the tank after I got it cleaned up a bit.

And the obligatory short video of the bike in running order, sorry for the poor quality, iphone videos are not the greatest.


Hopefully I can get a little more done this week, I still need to finish cleaning up the fenders, the seat, mounting up the air boxes, brake adjustments, and get the clutch cable adjusted.

you can get the exhuast collars from servicehonda.com. I had a hell of a time finding the right ones myself as the 68/69 pipes (cl and cb) have different collars than the later years.

http://xtremeusa.com/fiche_section_detail.asp?section=121119&category=MOTORCYCLES&make=HONDA&year=1968&fveh=2899

here you go. $3.34 a piece.

edit: make sure to look at your headers, as I mentioned there are two different collars, one type is longer because the headers look like they do in the above link. However if your headers have about a 2inch long piece of metal wrapped at the end (as opposed to the flared ends in the above link) then you need to get the later exhaust joints. The part number for the later (shorter) collars is COLR, EX. PIPE JOINT 18233-318-000. The part fisches are misleading because they are the same drawing, however the pipes changed I believe after 69, and you can see #2 on the 1968 has a different part number than #2 on the 1973 fische.

Hope all that made sense.


edit2: just realized you already ordered one from ebay, :facepalm: