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Discussion Starter · #1 ·
Hey thanks for the add!!! I just recently picked up a 1972 honda 350four. The electrical is all kinds of janky. The electrical start didn't work and the kick was broke off inside of the crank case. I replaced the kick shaft spindle and bought a new kick start lever the bike fired right up ( this was about a week ago) when I come home from work I'll fire her up ( no choke needed ) starts on the first kick and plunk around the neighborhood and put her up. She seems to be missing on one of the cylinder. Well today I decide to be adventuresome and tried to ride to my parents house ( about 10min away). She killed on me 4 time! I got her up to fifth and the rpms slowly crawl for 7 on down till she died... and it would take a miracle to get her started again. Ended up having to get the truck and trail and haul her home. Got home she fired right up. I'm fairly new to bikes I've been playing with them for about a year. Any help would be great any pointers. Rebuilding the carbs is my next step.

P.S. I forgot to shut the petcock valve off and lost about 1/2 a tank of gas all of the engine the night before riding. She still started up fine and road the neighborhood fine before going on to the parents. Thanks again for any starter pointers.

I know shes not much to look at right now
 

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These are great bikes, my favorite I think (and Soichiro Honda's too). FYI -- there is a SOHC/4 (single overhead cam, four cylinders, like your 350F) group: The SOHC/4 Owners Club. I'm over there with the same handle, and you'll find tons of info. I've had a dozen or more 350Fs over the years, including one I've owned for 20 years. Great bikes.

That out of the way -- you need to do a complete 3000-mile tune up before going any further, including running old oil and gunked up carbs.. Get a manual. Change the oil and filter. Leaking gas is obviously dangerous -- you're either in need of a petcock rebuild or carb rebuild or both. Valves (adjusted cold), points cleaned and gapped, new plugs, check your air filter, change your oil and filter, time it, rebuild and sync your carbs. I'd check other stuff as well -- check your tires, check your forks (leaking? pitted?), check your triple tree -- cracked?, check your brakes, check your chain and sprockets. IF this stuff sounds intimidating, well -- it can be at first. But you need to do this stuff to make sure you aren't damaging (any further) what you have.

The bike running and then shutting down could be a few different things -- gunk in the carbs, clogged vent in the tank cap (have you checked the inside condition of the tank?), bad wiring, etc.

Taking the carbs of to rebuild them -- and do a thorough job when they are off -- is a pain in the ass with the airbox, but it's got to be done. It's possible to remove the float bowls with the carbs on the bike, but I only do that once I know carbs are good to go.

I'd look into replacing that exhaust as well. IT looks like it's open which will piss off your neighbors and possibly cops, and your bike will run better. Cb400F pipes fit but you have to replace the pegs with 400F pegs and the kicker with a 550F kicker, but other people make 4-1 and 4-2 systems.

For your starter, does the starter turn? It could be the starter itself -- or it could be the teeth in the gear inside the engine.

And if someone tells you to remove the airbox and put pods on it, don't listen.

Anyway -- good luck.
 
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Discussion Starter · #3 ·
Thanks Chicken for the reply!! What little history I know of the bike. I am the 4th owner. The 3rd owner bought the bike for $1100 ( not running ) and spent another 350 to get it running. Supposedly the all the plugs were changed and oil/filter was changed. The guy told him it would be $1100 to clean and rebuild carbs. I'm no expert on cleaning carbs.... but that's ridiculous. Yes the started is bad and needs to be replaced. There is no air filter in the box I want to go with pods lol I like the look. 1st pic is my bike the 2nd is my vision for her. Also heres a pic of the kit I'm going to buy for her.
 

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I'd try to verify what you've been told. Changing the oil and filter are pretty cheap...

Be wary of aftermarket brass (jets, needles, valves) for these bikes. They are often of inferior quality to OEM. Best thing is to keep your original brass and make sure it is thoroughly cleaned when you rebuild your carbs. IF you buy that kit, it also has an air filter. It's your bike, do what you will, but I would try to convince you not to go with pods, you won't gain anything over the stock airbox and you might have running issues. I'd also advise you to fiddle with one thing at a time. Rebuilding carbs with non-OEM brass and then adding pods at the same time means that if it runs wonky you'll be chasing down the issue.
 
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I'd get float bowl O-rings and the O-rings for the jets. You might not need to replace the top gasket, but you could do it while you've got things apart for piece of mind. I'd also take off your carbs and pull 'em apart before ordering stuff.
 
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Discussion Starter · #8 ·
Ok thanks for the advice. I'm hoping to pull them apart over the weekend. And see what's going on. I'll keep ya posted!!
 

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Do not bother with a rebuild kit for the carbs. Just go to your local Honda dealer and get the rubber parts for the carbs, That is all that is really needed unless someone has taken pliers to all the brass parts, which I have seen.
TOOLS
 

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Discussion Starter · #10 ·
Ok... I'll see if they have them/ have to order them? So get rubbers and gaskets? Why dont after market parts work well? Any special cleaner to soak jets in? I've read that Gunk Carb cleaner is what a lot of people use.thabks for the help guys.
 

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I just re did a 73 350f, I ordered the total carb rebuild kits from "2fast moto" and I remember many of the new pieces were different and did not even fit the carbs, had to clean and use the oem pieces. If I was you I would definitely avoid those kits. Ordered parts from 4into1 for my cb175 and everything fit perfectly, though the quality was significantly inferior to the original parts, I guess it's a toss up for aftermarket kits lol. As for carb cleaner my dad bought a gallon can at Napa auto that has a little basket you can dunk parts in with, and that stuff works miracles.

These 350fs have a tendency to eat cam chain tensioners (my bike had 3k miles and jumped time and bent two valves and my dads cb400f tensioner wore out in the same way simply because the previous owners did not take care of maintenance) so a word of advice I would make sure you keep your cam chain adjusted the results could be catastrophic lol

Anyway hope this helps 350fs are great little bikes
 

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Discussion Starter · #12 ·
Awesome 4:1 off of Ebay is where I was going to get the seals from and the gasket... I know very little about bikes but I'll do research on the Cam chain and check all of that... I cant thank you guys enough for the tips.. the carb cleaner I'm looking at has a basket also... my common sense is telling me not to put any rubber parts in the cleaner...?
 

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You're right, no rubber parts in the carb dip.

I've got to say Tools and CarnivorousChicken are pointing you in a good direction, please hear their wisdom.
Pod filters won't bring you joy, only misery.
Stock airboxes lead to bikes that run.

Do join up on www.sohc4.com/forums
There is much to be learned there specific to your bike. Someone there has every answer to every question you are going to ask. I promise you that!

Read through hundreds of threads specific to your bike, learn what goes wrong and how to fix it before YOUR bike needs it. You'll gain confidence as your knowledge grows, and with every issue on YOUR bike that you've conquered, you'll be more ready to handle the next. Its a good group there.
You can find me there under the same name too.

Alan F.
 

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Discussion Starter · #14 · (Edited)
Thanks Alan F. I tried to join the other day but go this reading ( pic below). Your link wont open either. I have a 83" suzuki 650 tempter I already have pods on lol I'll try and be happy with them I dont know why I like the pod cafe style so much lol. I am keep this bike as orginal as possible.
 

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Discussion Starter · #17 ·
Ok so carbs came off today and started the journey of taking them apart. On of the 4 bowl spring is broke and the brass it holds is missing its rubber seal. The tip of the carb with the main jets go look kinda bad in my opinion. The slow set holes on all for are super nice and clean. Going to watch more YouTube and take the rest apart... whoever took it apart last used a lot of sealant on the bowls.
 

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