Author Topic: 1972 CB350F First RestoMod  (Read 8395 times)

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Offline zammykoo

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Re: 1972 CB350F First RestoMod
« Reply #25 on: May 10, 2016, 10:47:36 AM »
I doubt the tail light conversion would release sufficient taxing to satisfy a second HID. This dual lamp conversion is something I've explored for a build but shied away from for this very reason. Absent of a major upgrade to the alternator or using an aftermarket stator designed for battery-less operation (with CDI) you'll likely not get there.

Any chance you could find/use 1 HID and a single LED projector instead. That may get you there. And lastly, in some states, those won't pass Inspection because they don't have the focus planes or dimmers as HI/LO operation. Depends upon where you live, and how sticky the Inspectors/Cops are. If the lens doesn't have DOT approved on it, ticket time for you!

True that. The more I think about it I may end up going with a single projector setup and retrofit that into a headlamp bucket (has high beam solenoid). And this could be a phase two thing once I get the bike running.


Good to see another 350F project! Welcome to the forum, looking forward to seeing where this goes.

Likewise, I have been enjoying watching your build progress! But hey, I noticed your little commotion about the scratched cylinder, I hope that all works out. I have been meaning to get around to cleaning mine to further inspect, but so far they look ok.

Offline zammykoo

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Re: 1972 CB350F First RestoMod
« Reply #26 on: May 10, 2016, 11:00:36 AM »
So it took much longer than I wanted the this darn cylinder block is finally off! Piston #3 was stuck in there good and did not give up without a fight.

I removed all pistons and proceeded to clean 'em up. First tried ultrasonic/SG first, then the chem-dip. I started seeing good results after the chem-dip, so I'm not sure if the ultrasonic/SG bath helped much. I plan on putting together a makeshift blast cabinet so I can do some soda blasting as well. Rings are still seized to piston #3, not sure if I can get them off. I'll try applying some heat and see how that goes.

The cylinders look pretty smooth with no obvious scores/scratches. I need to clean it up a bit more and remove carbon to fully inspect, but looks ok so far.

Bonus question: These pistons have one-piece oil rings. Can three-piece rings be used interchangeably?





« Last Edit: May 11, 2016, 06:53:28 AM by zammykoo »

Offline sbeckman7

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Re: 1972 CB350F First RestoMod
« Reply #27 on: May 10, 2016, 03:37:34 PM »
Looks like you're making good progress.  How is that ultrasonic cleaner treating you?  I ended up returning mine after trying a few parts with it, as it was good but not great.

I ended up saving my scored cylinders thankfully.  It sounds like you're also planning on installing new rings?  I would highly recommend it after what happened to me!

Offline zammykoo

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Re: 1972 CB350F First RestoMod
« Reply #28 on: May 10, 2016, 07:35:23 PM »
Looks like you're making good progress.  How is that ultrasonic cleaner treating you?  I ended up returning mine after trying a few parts with it, as it was good but not great.

I ended up saving my scored cylinders thankfully.  It sounds like you're also planning on installing new rings?  I would highly recommend it after what happened to me!

I'm experiencing the same with my ultrasonic cleaner. I think it has its place as a cleaning machine but it doesn't seem to be meant for engine parts - at least not this model. I bet it works well on jewelry, etc.

And yes, I'm planning to get new rings too but I need to know if the three piece oil rings are interchangeable with this first.

Offline Hurstman1972

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Re: 1972 CB350F First RestoMod - 3 Pc Oil Rings
« Reply #29 on: May 11, 2016, 05:54:01 AM »
Hmmm. I rebuilt mine with one piece oil rings that seem to be working OK, although I'd druther have the 3 pc style. If you know of a source, pass it along! Thx!

Offline sbeckman7

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Re: 1972 CB350F First RestoMod
« Reply #30 on: May 11, 2016, 07:12:58 AM »
I did a quick search for 3 piece oil rings as well before buying the eBay set.  They just don't seem to be out there for these little engines.

Offline zammykoo

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Re: 1972 CB350F First RestoMod
« Reply #31 on: May 13, 2016, 10:42:30 PM »
Progress has been slow due to life  ::) (yeah I know) but I've been looking at different abrasives and polishes to test on some covers. I just attached a spiral buffing wheel to my drill press with white compound and looks like it's working quite well! I used a brass wire wheel first, but looks like it might be too abrasive. I'll have to go back and use something with finer grit and repolish.



What it looked like before:


Then started carb disassembly. It got late so I didn't get to finish, but I noticed something very worrisome. One of the main jet posts are chipped at the end.
It doesn't appear to go as deep as the gasket, but still want to ask for your thoughts. Do I need a replacement body?   :-\





Offline zammykoo

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Re: 1972 CB350F First RestoMod
« Reply #32 on: May 15, 2016, 09:13:16 AM »
Oh god, what did I get myself into... getting ready to do a deep cleaning. I need to get a rebuild kit too. If the jets are good, is this what I need? Honda part #16010-333-315. Looks like I can get 4 sets for $60 shipped.

Looks like the kit includes:

Float bowl O-Ring gasket
Float needle valve seat o-ring
Float bowl drain screw o-ring
Air mixture screw o-ring
o-rings for the line that connects the carburetors
Top Cover Gasket

And for the vent tubes (that links from one carb to the next) would I find that at a local hardware or auto parts store?


« Last Edit: May 15, 2016, 09:28:14 AM by zammykoo »

Offline zammykoo

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Re: 1972 CB350F First RestoMod
« Reply #33 on: May 15, 2016, 03:34:57 PM »
I may have lucked out because it seems like the previous owner began doing a rebuild but never finished. They installed fresh top and bottom gaskets (or appears to be new). They popped off with ease upon unscrewing the bowls/covers. I can probably go ahead and use these, which leaves me with needing new o-rings.



Trying to look at all of my options here. I can place the order the kits posted above and wait a week to receive them... or run to the local HF and try one of their assorted o-ring packs. http://www.harborfreight.com/225-piece-metric-nitrile-o-ring-assortment-67609.html

Based on forum member danfr's post, the pack contains all the needed sizes (close enough in measurement). Maybe they will work? It's only $5 for the pack - I'll give it a try and report back.

thanks for the reply Bryan.

I did some more digging around and I think I found the sizes although I'm not too sure how credible the sources are. I figure I'd post my findings in case someone with a 350F or 400F is looking....

Main jet O-ring:
1.2mm cross section x 3mm I.D. Quantity 4

Float Valve Seat Seal
1.5mm cross section x 5mm I.D Quantity 4

Fuel Connect
1.9mm cross section x 5.8mm I.D Quantity 12

I think I remember Hondaman stating that most metric O-rings range by 0.5mm so I may need to do some rounding. Also I think he mentioned Buna fits a bit bigger than Viton or Visa Versa...??

I still need one top gasket. Maybe I'll search the salvage yard this weekend.
« Last Edit: May 15, 2016, 03:38:03 PM by zammykoo »

Offline sbeckman7

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Re: 1972 CB350F First RestoMod
« Reply #34 on: May 16, 2016, 04:43:22 PM »
Let me know if you decide you do want to get OEM rebuild kits.  I have 4 of them unused as I was going to rebuild my carbs and then found my insides to be beyond repair.  Yours for $50 shipped! 1 set was opened, the other 3 are still sealed.

Offline zammykoo

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Re: 1972 CB350F First RestoMod
« Reply #35 on: May 17, 2016, 10:13:26 AM »
Let me know if you decide you do want to get OEM rebuild kits.  I have 4 of them unused as I was going to rebuild my carbs and then found my insides to be beyond repair.  Yours for $50 shipped! 1 set was opened, the other 3 are still sealed.

I appreciate that, Spence! If I can't get the o-ring set to work, as previously mentioned, then I may go for that. What rebuild kit did you get?

Offline zammykoo

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Re: 1972 CB350F First RestoMod
« Reply #36 on: May 17, 2016, 07:49:24 PM »
Playing with some polish. Took about 5 mins on the polishing wheel for these nice results :)


Offline sbeckman7

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Re: 1972 CB350F First RestoMod
« Reply #37 on: May 18, 2016, 11:26:06 PM »
Looking good :)  The rebuild kits I purchased are Genuine Honda ;)

Offline zammykoo

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Re: 1972 CB350F First RestoMod
« Reply #38 on: May 19, 2016, 09:07:11 PM »
Looking good :)  The rebuild kits I purchased are Genuine Honda ;)

Good to know! I'll definitely let you know if my o-ring idea doesn't work out. I'll have a better idea this weekend when I can swing by HF.

Offline zammykoo

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Re: 1972 CB350F First RestoMod
« Reply #39 on: May 19, 2016, 09:10:51 PM »
Well these carbs are full of surprises! I had an "oh snap" moment (literally) with one of the fuel connectors tonight. If anyone knows where to get one of these I'd appreciate it. If not maybe I can rig one up somehow...



And got more goodies today!


Offline sbeckman7

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Re: 1972 CB350F First RestoMod
« Reply #40 on: May 24, 2016, 11:17:41 AM »
I have the connectors along with my full set of spare carbs

Offline zammykoo

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Re: 1972 CB350F First RestoMod
« Reply #41 on: May 25, 2016, 03:09:39 PM »
I have the connectors along with my full set of spare carbs

Cool thanks, I'll keep that in mind. I'll see if I need anything else after checking out the local dude's spare parts.


A side question for all. Feels kind of like a dumb question but I'll ask anyway (I couldn't find a definitive answer). Do I need to split the cases and rebuild the bottom end while I'm working on the top end? This bike has not been running for at least 25 years. The kick starter spins the crank smooth as butter after I removed the stuck piston. There has been oil sitting in it I believe this whole time, and I feel no resistance while shifting through the gears. Maybe the seals need to be replaced anyway?

Offline Bankerdanny

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Re: 1972 CB350F First RestoMod
« Reply #42 on: May 26, 2016, 02:22:03 PM »
The definitive answer is maybe. LOL

On the one hand the SOHC's are pretty robust and so chances are good that the bottom end is in fine condition. On the other hand you already have the engine partially disassembled, so there is an argument for splitting the cases and inspecting the mains and gearset. If they look good you can button it back up.

The obvious downside of choosing to believe that the bottom end is in good shape is that if you are wrong you have to pull it apart all over again.
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Current: '76 CB750F. Previous:  '75 CB550F, 2007 Yamaha Vino 125 Scooter, '75 Harley FXE Superglide, '77 GL1000, '77 CB550k, '68 Suzuki K10 80, '68 Yamaha YR2, '69 BMW R69S, '71 Honda SL175, '02 Royal Enfield Bullet 500, '89 Yamaha FJ1200

Offline zammykoo

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Re: 1972 CB350F First RestoMod
« Reply #43 on: May 26, 2016, 05:31:45 PM »
The definitive answer is maybe. LOL

On the one hand the SOHC's are pretty robust and so chances are good that the bottom end is in fine condition. On the other hand you already have the engine partially disassembled, so there is an argument for splitting the cases and inspecting the mains and gearset. If they look good you can button it back up.

The obvious downside of choosing to believe that the bottom end is in good shape is that if you are wrong you have to pull it apart all over again.

Ah,  word of the wise.  I was in the fence but this is the push I needed.  Hopefully I can get to it this weekend!