Author Topic: 1972 CB350F restoration (Read 7729 times)

Sparked · « **on:** February 09, 2009, 04:09:29 PM »

I bought this bike with the intention of cleaning it up, tuning it, adding some gas and then be riding come spring (2007). Well I started with the cleaning, and found silicon around the head and cylinder gaskets. I knew it had at one time been laid down on the left side, well, it'd been laid down on the right side too.

So I decided to really have some fun with it, parked it in a shed and helped my dad build his garage (or more a woodshop with a garage door) and then before the sawdust started flying strip and rebuild the 350.

I'll have it on the road this spring for sure. Started it for the first time ever this weekend and that's a story in of itself. I'll post pictures and share some of the lessons I've learned in rebuilding the bike in this thread. I know one thing, I wish I had found this forum awhile ago. Reading some of the threads I've found answers to questions that had me hitting my head against the wall.

stay tuned.

Tim in Ohio · « **Reply #1 on:** February 09, 2009, 04:21:58 PM »

Welcome to the forum. I'll be watching for your updates.
Tim

keiths · « **Reply #2 on:** February 09, 2009, 04:32:39 PM »

I had the same problem before finding this forum. We will all be watching your progress.
Good Luck,
Keith

Hush · « **Reply #3 on:** February 09, 2009, 05:58:02 PM »

Yep us 650 rebuilders live here too

hoodellyhoo · « **Reply #4 on:** February 09, 2009, 07:05:25 PM »

Welcome. Glad to see yet another 350 thread.

mattcb350f · « **Reply #5 on:** February 10, 2009, 04:46:30 PM »

Quote from: hoodellyhoo on February 09, 2009, 07:05:25 PM

Welcome. Glad to see yet another 350 thread.

...I'll be watching this one too.

It kind of looks like it has a 400F exhaust on it, or at least the header. That's pretty cool.

Matt.

Sparked · « **Reply #6 on:** February 12, 2009, 09:34:27 PM »

Ok, here is a quick point form run down of what I've done so far, and what I have yet to do. Figured that'd be a good idea for a starting point.

What I have done so far:
-striped the bike down to the frame
-sandblasted and powdercoated frame, chain guard, swingarm
-replaced broken top bridge
-taper roller steering stem bearings
-fixed the wiring (broken ground for the lights)
-dismantled the engine, flipped the crank bearings and reassembled with new gaskets, seals and piston rings.
-lapped the valves
-replaced scarred rockers with less worn ones from donor engine
-quick cleaning of carbs with carbclean
-duct tape patched seat
-new clutch cable
-new throttle cables

What needs to still be done:
-rebuild carbs with carb kits
-sync carbs (3 cylinders are running super rich)
-new tires, tighten/align spokes
-paint the tank
-clean rust out of tank
-exhaust gaskets
-rebuild front brake and MC
-install rear brake
-new tach cable
-new chain / sprokets
-fabricate stopper for the center stand so it stops hitting the exhaust
-rebuild rear shocks
-rebuild front shocks
-there's probably still more to add..... lots of little details....

I'll be adding pictures that I have taken as well as asking questions as I go. I would like to restore the bike as close to original as possible eventually, but until then I'm working towards safe and reliable and rideable. It has spent too long sitting and waiting and it's really time to start putting some miles on the bike again.

Sparked · « **Reply #7 on:** March 13, 2009, 11:00:54 PM »

Ok, I've hit a little snag. I installed and reinstalled some new throttle cables on my bike and no matter how I adjust them I can feel the cable drag in the sleeve and it's enough friction to hold the throttle open on it's own. Is there a way to lube cable or what else should I be looking for.

(P.S. If I can figure out the posting of pics I'll get a few uploaded so you guys can double check the routing of the cables too)

Sparked · « **Reply #8 on:** March 14, 2009, 01:53:55 PM »

Ok, I figured out how to get some picture's up. Here is what my bike looked like the day after I bought it sitting on the deck.

Sparked · « **Reply #9 on:** April 22, 2009, 08:22:11 PM »

Man I am not keeping up with the postings as well as I should be. Currently I am working on the tank and sidecovers, getting them ready for paint. I had a crack in one side cover that I repaired with some ABS cement, then covered over with bondo. Bondo-ing the tank and trying to return it to a resembance of it's former shape has been a trial and a half but I got it to the point i was comfortable spraying the tank with primer and tonite wet sanded the primer looking for the last of the low and high spots.

I have new tires (Avon Roadrunner) and am going to take the wheels in a shop to have them mounted trued and balanced, not a job I wanna do myself and I'm getting itchy to getting the bike back on the road.

Rebuilt the carbs with all new o-rings over the weekend. Soaked the parts in simple green for about 1/2 hour and then scrubbed and assembled. then reassembled a few times trying to chase a leaky carb. IT sure dosn't take much at all to be left in the needle valve seat to hold it open and let the gas flood through.

I have a new chain, but was wondering if I should change the tooth count on my sprockets one or two teeth. I'm going to be doing 90% city riding, 10% twisty mountain roads and about 5% hiway... I'm thinking of keeping the bike honda stock and then maybe changing things on the bike if I feel it's needed.

I'm really getting itchy to get my bike done and on the road, I have my fingers crossed for the end of the month... But so much stuff I need to do, both with the bike and the rest of life.

HondanutRider · « **Reply #10 on:** April 23, 2009, 05:55:36 AM »

Sounds like a nice project...you'll have to post some "after" pictures for us to see.

Regarding your new chain, I'd consider putting new sprockets on at the same time, unless the old chain wasn't really worn. They tend to wear-out with the chain and its usually advised to replace the sprockets when doing the chain. I also would keep the same ratios as a stock CB350F. The bike has great gearing for around town and on the highway it already has to rev pretty high. It only is a 350 and they weren't noted for really long high-speed highway cruising. Sounds like your intended use is exactly what they were good at doing.

Sparked · « **Reply #11 on:** May 01, 2009, 05:19:35 PM »

I'm painting today.

So excited, master cylinder kit and sprokets will be in middle of next week, and I'm going to get a stainless front brake hose built for it. So if I paint like a mad man next week (out of town on the weekend again) I should have a road worthy bike come next weekend.

taymoor · « **Reply #12 on:** May 01, 2009, 06:07:44 PM »

Sounds like an awesome project. I'm restoring the same model. Just curious... where do you get the ss brake lines made?

Sparked · « **Reply #13 on:** May 01, 2009, 06:37:33 PM »

I'm working on a few options. I'm going to go by a hose manufacturer that specializes in one off industrial hose applications and am going to see if they can build some for me. If not that Z1enterprises.com says that if I give them the fitting arrangements and hose lengths they can build ones to spec for me.

taymoor · « **Reply #14 on:** May 01, 2009, 08:20:18 PM »

I'm real excited to see yours as a finished project. The ss is gonna look awesome I'm sure.

Sparked · « **Reply #15 on:** June 26, 2009, 03:34:13 PM »

I'll have some pictures up soon.

But I got a question though, whats proper break-in procedure after rebuilding the engine? How many miles below what RPM before I can start to open it up?

Sparked · « **Reply #16 on:** July 23, 2009, 05:47:55 PM »

Well I got about 250 miles on the bike so far, and then last weekend something let loose. here is a link to the pictures of what I found. Looks like I'm going to be rebuilding the engine again.

http://forums.sohc4.net/index.php?topic=55459.0

Zaipai · « **Reply #17 on:** July 23, 2009, 05:56:27 PM »

Well that bites. Hope it goes better this time. You can just never tell about the quality of parts these days.

Sparked · « **Reply #18 on:** June 07, 2012, 12:51:00 PM »

She is back alive.
Cleaned out the carbs and got the donor engine running over the weekend. It is making a funky sound that I think is cam chain so I will have to check and see if it is stuck or not. Fires right up on the first kick though. :-):-):-)

Sent from my Atari

hoodellyhoo · « **Reply #19 on:** June 07, 2012, 03:49:07 PM »

Great job!!!

Sparked · « **Reply #20 on:** August 11, 2013, 08:49:16 PM »

Installed new bars with barend mirrors today. I like the riding position of it and the new mirrors are awesome. No vibration at all. Think I need to resync the carbs as the bike will accelerate by itself when idling. Above 6000rpm it pulls nice and strong.

MoMo · « **Reply #21 on:** August 11, 2013, 09:05:31 PM »

Nice, I checked out the link to the broken case-if the motor had been apart it is possible the snap ring that retains the bearing was not put in correctly

Sparked · « **Reply #22 on:** August 11, 2013, 10:11:38 PM »

Yeah it is completely possible that I screwed something up when I was assembling the engine. The new one has alot less miles on it, but was sitting out in the weather alot longer. I want to get it running properly so I can start on my 550 I brought home recently. I don't have enough space to work on more than one bike at a time.

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Author Topic: 1972 CB350F restoration (Read 7729 times)

taymoor

taymoor