Topic: My First Restoration - 1972 Honda CB350 Four

[72_350_FOUR]

Hi Everyone, my name is Jeff and I'm from Columbus Ohio and this is my first restoration project. I have always wanted one of these bikes and i found a really good deal on what was a kind of running bike so i new it was the right time to dive in head first.  I'm somewhat mechanically inclined, but have never tackled a project like this. Anyway to start with here are a few pictures.

#1 - This was the picture from the ad on Craig's List, and the guy pretty much implied the bike was running, and being ridden.  However when i got to the storage place (should of been my first clue) you could tell it had been sitting a while.  We haggled and i ended up paying what i thought was a fair price.  The Battery was dead and so we jumped it and it turned over but wouldn't start.

#2 - This is what the bike looked like when it got it home in the back of my truck.    A little different, you can see the carb overflowed all over the motor, and I eventually found out why.

#3 - This is what it looked like after wiping away the cobwebs and dust.

I guess the direction i am going to take is to clean it up the best i can and get it running really well, ad a few aftermarket products, and then decide what to do with her from there.

[72_350_FOUR]

Well after getting the bike home i put some fresh gas in it, jumped it and it fired up!!!  YES!   the i took it down the block and back and it ran like %^&*....  oh well at least it runs,,,
After i parked it, uh oh, one of the carbs was leaking all over the engine. 

I started by taking the seat and tank off.  The seat was tough because the lock had stripped out and so i couldn't even raise the seat, I had to take the lock off, when i opened it up the insides were in pieces, I'll deal with that later.  Next i took off the tank and drained it.  A little rust but nothing horrible, I'll get ot that later too, or may go after market, not sure..

As soon as i could i ripped all of the homemade LED lighting off that the guy i bought it from had installed.. i think he used speaker wire!  and the worse part is he drilled 2 holes in one of the side panels for a green toggle switch...  should be beat for that!    you can see it all in the big Ball of wiring picture...

Next i took off the carbs, and thanks to a great tutorial on this forum they came off easy!

[brooze72]

I guess the direction i am going to take is to clean it up the best i can and get it running really well, ad a few aftermarket products, and then decide what to do with her from there.

Welcome Jeff.  That is an excellent plan.  So many guys seem to want to dive into the deep end before seeing if there is water in the pool.  Once she's running solid you can add the farkles or whatever.  Great news that she fired up.  Now for carb service & the 3K tune up..

[72_350_FOUR]

Picture #8

I got the carbs apart and started cleaning, everything was going great and i figured the outside carb on the LH side was leaking due to a bad float or stuck float well i was wrong it was worse. One of the stems that the pin for the float goes through was snapped off.  So you guys came to rescue again and recommended Jim French to me. I'm shipping out the carb to him tomorrow hopefully, and he will micro weld it and according to him it will be better than new..  i can send you his website if you need it, i cant post it here for some reason.


So that pretty much brings the project up to date, I'm doing a little polishing etc.. while I'm working through the carb issue... Oh and the Previous owner dropped off the title, 2 sets of mirrors and all the airbox components to me today !!!!

[72_350_FOUR]

thanks Brooze,  3k tune up ?

[brooze72]

It's the recommended Honda service every 3000 miles.  Should be posted on our site somewhere..

[harisuluv]

Looks to be in fantastic condition.  I just bought a few bikes and a guy threw in a 350F motor.  Those must be some tiny pistons in there!

[72_350_FOUR]

A few more polishing pics. Each piece im getting better.  I'm just doing what i can without too much  part removal right now. Mirrors came out well, I have 2 sets so i will have some older ones for sale soon, along with a couple other items, stay tuned.

[dougan]

Looks to be in fantastic condition.  I just bought a few bikes and a guy threw in a 350F motor.  Those must be some tiny pistons in there!

Someone else on here posted this picture in a build thread.  I bookmarked it because it shows how awesomely huge the 350F cylinders are.

[lostinthe202]

           ^
            !
            !
            !

Ahhh, THOSE are the four angry squirrels I've heard about eh?  (hehe)

[Sage]

Hey Jeff, where are you located in Columbus?  I'm in Johnstown, and I am currently looking for a CB350 or similar for my first restore.  I'll be following your progress, and it would be awesome to see the bike in person some day, and to pick your brain a bit before I dive in.

Andy

[SOHC4 Cafe Racer Fan]

Clean motor.  What kind of power does the 350 Four make compared to a 350 Twin?  Just curious.

[HondanutRider]

Clean motor.  What kind of power does the 350 Four make compared to a 350 Twin?  Just curious.

Less

[72_350_FOUR]

Hey Jeff, where are you located in Columbus?  I'm in Johnstown, and I am currently looking for a CB350 or similar for my first restore.  I'll be following your progress, and it would be awesome to see the bike in person some day, and to pick your brain a bit before I dive in.

Andy

hey Andy, I am in Columbus (Worthington Area) I havent been at it a real long time, but i'd sure be willing to share what i've learned up to this point...  I am going to resume working on it this week, now that it's not 150 degrees outside... !!  i'll have it out and about soon, I hope, and would love to show it off.    I'll be posting some new pics soon also.

[brooze72]

Posted specs of the day were 350 twin, 36HP and 350F, 34HP

[72_350_FOUR]

Wanted to give a quick update.  I got delayed on this project last month due to going on vacation, and then when i got back not having power for 4 days, then it was about 102 degrees everyday which made it about 110 in my garage, even with a fan.  I worked on a few things anyway and lost 3 pounds sweating !  Anyway Jim French did an excellent job of Micro welding the tower back onto the carb body, it went together flawlessly. I got all new gaskets on the carbs, adjusted float level etc etc...and got them back together and back on the bike, however when i put gas in and turned the fuel on, my petcock was leaking, and also carb #2 was leaking. I'm not sure why, and I'm pulling them back off tonight....sigh!  to find the source of the problem.  Anyway i got the bike cleaned up pretty well and feel like I'm real close to whipping this carb issue.  Good news is all of the electrical works, so I'm happy.

[Sage]

hey Andy, I am in Columbus (Worthington Area) I havent been at it a real long time, but i'd sure be willing to share what i've learned up to this point...  I am going to resume working on it this week, now that it's not 150 degrees outside... !!  i'll have it out and about soon, I hope, and would love to show it off.    I'll be posting some new pics soon also.

Well, no matter how long you've been at it...it's that much longer than me...

My plan is to find something that runs well, and then I can gain some experience with the less technical aspects of the restore.  If all goes well, then maybe I'll tackle something more challenging.  Maybe when you've got it running we could meet up at some point, I'd love to see the bike and get your thoughts on how I should proceed.

Andy

[72_350_FOUR]

Well i worked on the bike last night, and my carbs were not what was leaking, it was actually the fuel line where it attaches to the carb.  The petcock however is in bad shape and leaking a lot, luckily i got an email yesterday that Bike Bandit has shipped the rebuild parts for it.  Also i noticed my tank has really rusted bad over the last month. I used the sea foam and nuts and bolts method to clean it, but it will have to be done again. I may try the reverse plating process i read about on here. 

One issue i am having is my throttle is really tight when the bike is turned to the right.  I tried different adjustments, but only got it working right when the bike is straight on or turned left.  the throttle will snap back as it should.  I may post this question over on the "bikes" forum also after i hunt around the tip/tricks to see if anything is there. 

All in all a great night of work last night, made a lot of progress.

[flybox1]

Nice work.  love the 350F
search the forum for VINEGAR and THE WORKS for tank de-rusting methods.
vinegar works great if you have a week, and is really cheap/biodegradable.

as you turn your bars to the right, the throttle cable is pinching somewhere, or at least, making a tighter bend.
loosen the lock nuts under the right control housing. they are on the thingamajigs, or snorkel looking chrome tubes that the throttle cables run into, as they attach to the control.  loosening the nut should allow the cable snorkels to swing freely from under the control. watch the cables as you turn your bars to full stop on the right.   you should see the cables 'pivot' check for snap back here. if snap back is good, secure the snorkels in this position with their lock nuts.  now, check for snap back with bars to the left.  if its less, you'll have to re-position the snorkels back in the direction it needs to be for the left.  find the midpoint and the happy medium for them

[jneuf]

Posted specs of the day were 350 twin, 36HP and 350F, 34HP

Interesting. I had never actually looked at the figures before. The 400f makes (as advertised anyway) 37 hp. So I'd imagine lined up side-by-side, a little 350 twin might "blow my doors off" after it starts turning rpms.

On another note, great looking project! The 350f is a sharp looking bike!

[72_350_FOUR]

Thank you guys, appreciate it.  Just trying to get her on the road!    I'll try your suggestion flybox, thanks!

[72_350_FOUR]

Throttle cables were zip tied to the frame by the PO.  when i turned to the right, especially hard they would almost be bent in half. Once i got rid of the zip tie they work fine. I just need to see what the stock routing is and if they are tied anywhere to the frame.  Throttle snaps back in all pos. now.

[SOHC4 Cafe Racer Fan]

Posted specs of the day were 350 twin, 36HP and 350F, 34HP

Interesting. I had never actually looked at the figures before. The 400f makes (as advertised anyway) 37 hp. So I'd imagine lined up side-by-side, a little 350 twin might "blow my doors off" after it starts turning rpms.

On another note, great looking project! The 350f is a sharp looking bike!

That's interesting. Maybe that's why the twins are popular race bikes. I wonder if the make more torque than a four. I saw on cafe racer that one tuner added 20 hp to a 350 twin.

[jneuf]

Posted specs of the day were 350 twin, 36HP and 350F, 34HP

Interesting. I had never actually looked at the figures before. The 400f makes (as advertised anyway) 37 hp. So I'd imagine lined up side-by-side, a little 350 twin might "blow my doors off" after it starts turning rpms.

On another note, great looking project! The 350f is a sharp looking bike!

That's interesting. Maybe that's why the twins are popular race bikes. I wonder if the make more torque than a four. I saw on cafe racer that one tuner added 20 hp to a 350 twin.

Can't find the torque specs on the 400f, but the 350 twin makes 18.4 lbs. @ 9500 RPM, and it's max HP is at 10,5000 rpm as well. 400f makes its max HP at 8500 RPM, so I can imagine it's making quite a bit more torque down low.

Now I want to see this drag race!

[brooze72]

Wow, that seems unusual having the max torque & HP at such high RPM, what is the redline on those motors?  Most bikes seem to peak before the redline & then taper off.  Give us a link to those curves please, just curious.  I want to see that race too! 

[SOHC4 Cafe Racer Fan]

Now I'm even more interested.  That would make for an interesting race.

[72_350_FOUR]

Well i have the old girl running pretty decent.  I installed a Dyna ignition, and found the PO had the wires reversed going to the coils, so that's why i was having so much trouble getting it to time right, I feel pretty dumb on that one, never even thought to check,... found it when i was installing the Dyna.  Anyway it's missing around 3/4 throttle range, and everything I'm reading in the Honda carb manual is pointing to lifting the needle a notch, plus a new air filter. Everything is stock except the 4 into 2's...... if that doesn't clear it up I'll look at increasing the mains.  Last night was the first night i really had her out and running for a while. Wow i love the sound of this motor, I'm becoming quite attached.  i think if i could cruise down a never ending country road at 30 mph..I'd never come back, at that speed she sounds like she would run forever....  Still have to adjust the tappets, and then i want to re-synch the carbs, and then I'm gonna RIDE.   I made some overflow tubes for the carbs since the PO lost the originals, now my # 2 carb is leaking a couple drops after shutdown, or maybe it was before and i was evaporating before i noticed, now it's on the floor. so another float level check will be in order too.  Right now I'm just shutting off the gas and letting it idle a little bit, that seems to almost stop it. All in all I'm happy with where I have brought it in this short time.

[72_350_FOUR]

It's been a great summer and i sweated my arse off all summer in the garage but it's been well worth it.  I finally have the bike tuned and it is running great, chocolate brown plugs on all cylinders and pulls through the gears without any hesitation or missing.  I found they key was to completely get all of the stock airbox components in place and tight, then once i got a new airfilter, and added the mac 4 into 1, and really synched the carbs the right way, it was an unbelievable difference. What a fun little bike.  Now i'm just working on detailing it, and deciding where to go from here...

[72_350_FOUR]

Some more pics.

[Mugen_Stumpo]

looks very nice, congrats

[72_350_FOUR]

Got my Rotor from Scott today, I dont know if i should put it on the bike or frame it !!!!  LOL!  it is bad A$$ !!! 

[Jinglyjangly]

Hi nice bike, Ive got two once I have owned since new in 1976 have attached a photo
of it when it was a couple of weeks old. Im afraid to say took it apart in the 80's to
give it a good clean and its still in big lumps, although I have had the engine refurbished
but its at the end of a long list of projects, I have another which I run occasionally which
I bought for spares but is too good to break. I have got to say that back in the day
the kawa 400 twin was slightly faster topend, but the honda could catch up in the twistys
and I think they handle better than a 400 four, but could do with a sixth gear
attached a pic of mine in cyprus 1976 , (due to the war in cyprus it had been in a showroom
for a few years)

[iron_worker]

Great bike you've got! You've cleaned it up very nicely. I would love to restore a 350 four one day. I think they are a sweet little engine.

IW

[72_350_FOUR]

Thanks Guys.

[72_350_FOUR]

Just a quick update to show my new additions.  A cafe fairing, a new drilled rotor and some new turn signals for the front.  the turn signals are actually for British bikes, but the 5 inch stem on them was just the ticket for getting around the sides of the fairing.....I'm not thrilled with the bar ends, they vibrate alot and i have to keep readjusting them..I ordered some different mirrors which are more of a sport bike rectangular type, i hope they are better.... The fairing is great to tuck behind and open the throttle