Topic: Padawan seeking Jedi Night (cb350 four)

[Dos]

Hello, about two years ago I purchased a cb350 four in mint condition. It ran great with a slight cam chain rattle. After 6 months I decided to tighten the cam chain tensioner bolt and snapped the bolt off.. Yes I know rookie mistake.

Long story short I brought it to a guy and my engine was reassembled and now there is a knocking in my engine.. I could definitely take the top end off and see if it's my valves and check things out however I'm afraid I won't be able to put it back together. I was told by another mechanic that trying to do it myself with out someone who knows these old bikes will result in a negative result.

Can someone help me take off the top end and put it back together? I live in northern jersey. I want to learn how to work on this engine and pass the knowledge down.

My bike is very clean and full stock. The bike runs however this other mechanic says my carbs definitely need to be looked at. I am owning up to doing the carbs my self however this mechanic also said a certain type of rebuild kit is garbage. I want to avoid that which rebuild kits do you recommend?

[flybox1]

First - Ditch the mechanic and do it yourself, with the help of the forum.
Second - Complete a full tune-up.  Valve adjustment, timing, cam chain, carb cleaning, etc....and finish your hard work with a carb vacuum sync.

All if this is cheaply done, and will take care of most, if not all rattles. 
No need to jump into the engine until all the easy/cheap stuff is done.

Any carb rebuild kit is fine if you ONLY use the soft parts - o-rings, gaskets, etc.   The brass jets in kits are typically garbage. 
IF you need new jets because yours are completely corroded and beyond use (i doubt it ) buy keihin jets from siriusconinc.com or jetsrus.com.

[flybox1]

..and get the pre-formed 5-sided float bowl gaskets. 
The round ones s^ck 

[Dos]

Thank you I greatly appreciate your response. Im going to go for it.

[Dos]

This is the thing. I had the valves, timing, compression.. everything tested once I got the bike back from the guys that re assembled my bike by a guy I met on here.. After the bike was tuned about an hour in there was this knocking sound.

The problems with the bike are this:

1.Knocking in engine. If revved to quickly the bike will die.

2. When the bike is revved it will spike up a couple thousand rpms and then dip back down.

I will post two videos.. I know these are hard to diagnose but maybe the quality is better..

The reason why I am posting this is because I don't want to take apart carbs and rip things out if I only need to do one thing in the engine.

 <--- at 1:15  is when you hear it

This is the most recent! 

<---- you can hear the knocking immediately.

I have been told my valves are bent OR a piston rod OR Piston rod bearing..

[flybox1]

1.Knocking in engine.  valve lash might be off, cam chain not tensioned properly, carb vacuum imbalance   If revved to quickly the bike will die.  Could be vacuum leak, dirty carbs, bad fuel level in bowls, carb vacuum imbalance

2. When the bike is revved it will spike up a couple thousand rpms and then dip back down. Could be vacuum leak, dirty carbs, bad fuel level in bowls, carb vacuum imbalance

Do the tune up items before anything else. Please!

[calj737]

+1 to what Flybox is telling you.

Save yourself some money and frustration and buy a vacuum synchronizer tool. It will last for years and years and allow you to insure your multi-carb bikes are running spot on. Also, check for vacuum leaks around the intake manifolds and carb boots before you begin the tune-up. It can throw things off while tuning your carbs.

[Dos]

Okay.

I'm positive it is not the carbs but I will rip them out.. I put my screwdriver up to the engine and knocking is vibrating through the engine. I've tested vacuum leak and have applied glue around the boots on the airbox side to ensure no leaks

[Dos]

When riding back from the first mechanic that took apart the engine and ripped me off the bike was smoking through the breather exhaust and muffler.. It was also getting very hot. I have also adjusted valves multiple times

[754]

Did the valves keep getting loose, mostly on one side ?
 If so..classic oil starved cam issue..

[Dos]

Hmm yes oil starvation. How can I make sure oil gets to where it needs to get? How can I figure this out?

[flybox1]

I've tested vacuum leak and have applied glue around the boots on the airbox side to ensure no leaks

Causing yourself more issues, Dos.
Nowhere in the HONDA shop manual does it call for glue, sealant, liquid gasket....on any carb part.

754 mentioned Oil starvation -  Sure, it could be this, but i doubt youve even checked to see if you have a valve continually getting loose?  Dont jump to this conclusion just yet.

You should eliminate all other items on the the tune-up list before pulling the engine.
Once your bike is tuned, you can check through the tappet holes to see if everything is wet with oil.

[camelman]

I agree with the prior statements about tuning up the ignition/carbs. A poorly running 350F will sound like it's going to explode.

[754]

I dont know the oiler routing on 350 ,but i had the changing valve clearance on mine , adjusted several times over a month or two.. Its a bad sign.. Sure enough , one side of my cam got eaten , plus bearing and some rockers.. In your case that may mean a new head.
Not saying it has to be that but, if you can get valvecover off in the frame you can check it out..
 Is it noisier on one side of the motor.?

[Dos]

The bike was getting very hot when I rode it back from the mechanic after the engine was resembled. I wouldn't be surprised if that trip with the improper construction of the engine messed up the valves.  I remember seeing oil on the valve rockers. Tomorrow I will check clearances of the valves again but most likely I am going to take the head off. What creates oil starvation? did anyone listen to the vids?

again I don't  feel comfortable taking off the carbs and top of engine that's why I am looking for a mentor.

I have had the bike looked at quite a bit after the initial work done from the shotty mechanic. Yes the carbs probably need work but this knocking is coming from the engine for sure. 

[DaveBarbier]

Yes the carbs probably need work but this knocking is coming from the engine for sure.

If the carbs need work, they won't be making noise. The engine would because of improper sync.

If you don't feel comfortable with removing and rebuilding the carbs alone, I'd send to James (Harisuluv) for a rebuild so you know[i/] they're not the issue.

I see you're asking for someone to come by and give you a hand. If you were closer I'd come by real quick.

Hope this is coherent. I've had a few Manhattans.

[flybox1]

Tomorrow I will check clearances of the valves again but most likely I am going to take the head off.

Really?

Sorry, but i'm out.
Good luck.

[Scott S]

 You don't have to remove the carbs to sync them.

 You seem bound and determined to tear this thing apart.

 Just try one more time to adjust the valves, cam chain and check the timing. THEN, sync the carbs. You'd be surprised what a good carb sync will do for these bikes.

[Dos]

Alright I will do general maintence and check things out. I've noticed discoloration on my exhaust pipes.

Also are my valves supposed to make this sound?

[flybox1]

Taking your spark plugs out makes kicking it over, or turning the crankshaft over @ the big nut easier, and less stressful on the engine. 
Your valve spring retainers look wet with oil.  That is a good sign.
Because of the movement of the camera, its hard to tell where the noise is coming from.

[Restoration Fan]

Something else to try...update your personal info and put your location on there.
You never know just how many SOHC member might be near you.  But you'll never know unless you put your location there.

[Dos]

The ticking is coming from where the valves are when I dry kick it

[Dos]

updated profile. If anyone has a carb syncing tool around me and is nearby come on by and lets sync!

[calj737]

I see you posted an Want ad for a 550. Are you planning defeat with this little beauty? Shame on you, Dos! You can sort this thing out pretty easily. You've got to diagnose things, step-by-step. Whatever money you might spend at a bike shop, is far far greater than buying a few essential tools.

Grab the electronic manuals, do one service piece at a time of the 3,000 mile service. Its really not that hard, trust us. If you are absolutely unable (resources, time, space, etc) to work on and twit with a bike, then honestly a 40 year old bike (despite thumbing fetching and cool) may not be in your best interest. These should be efforts of passion and enjoyment, not frustration and fear.

Now, if I've misinterpreted your intentions, please do pardon my being forward. But sometimes new riders and members become overwhelmed due to preoccupation, not actual experience. And talking them off a ledge becomes necessary. And sometimes, simply walking away for a day or two to collect your thoughts is needed. Find 1 thing to do, then do it. Wait a day and do the next. You'll find it very easy and confidence building. Pretty soon, Spring will be here and you'll be cruising the gorgeous byways in NJ heading to the Catskills on the bike you made run!

[Dos]

Thanks man, Yeah i've just put so much money into this bike and yeah. tomorrow is another day.