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Hey guys, Elliot here from boston, obsessing over getting this old '72 350 to fire up. Feeling close. Turns over but won't quite get there. Losing sleep over this thing.


SO FAR New and charged battery. Clean carbs (although the jets might be upside down- I can't find ANY instructions that detail the correct orientation of the slow and primary jets in the carb- Shallow or deep side up??). New solenoid. Good spark. Strong neutral light. Fresh oil. Fresh Gas. Cleaned Gas can/lines/filters. I don't have a compression gauge but the compression seems strong when I give it a kick.

WHEN TRYING TO START- the engine turns over. I could be wrong about it sounds as if the left cylinder isnt firing. There is a hole in the left muffler the size of a quarter were the muffler connects to the pipe. Putting my hand over the pipes i feel a lot more blast coming out of the right side. cranks and cranks but won't catch. Could this be a compression issue? a timing issue?

ELECTRICAL ISSUE - I came home tonight and my bike's taillight was on. There was no key in the ignition and the killswitch was in the off position. The lights were in the off position. With a loud WTF I disconnected the battery, feeling confused and discouraged. Any tips on the next step in dealing with this?


I'm brand new at all this. Any and all advice would be enormously appreciated. You guys are my only life line here.
 

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I don't know how you could get the jets in wrong, as only one end has the screwdriver blade slots. If you're talking about the mix tubes, the ends with the holes in the sides go into the body first.

You need three things for an engine to fire: proper fuel/air mix, compression, and properly timed spark. Smell the exhaust after a start attempt - smell of gas? Check the timing with a light to see that sparks occur at the timing marks, on the compression stroke.

As far as the electrical issue goes, your key switch has three positions: OFF, ON, PARKING. That last position turns off everything but the tail lamp. Lots of riders killed a battery with that key position.
 

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Thanks for helping me understand all this.

Yes, the jets are in correctly, I was referring to the small brass mix tubes that go in after installing the jets. Each tube has two notches along the sides where an o-ring could potentially go. This makes it confusing as to which notch to place the o-ring. Each tube is bored out on either side. There is a shallow hole one side and a deeper hole on the other.

Is it deep hole that goes into the bod ? towards the jets?

After attempting a start I do smell gas. Can I narrow it down to a timing issue?

And yes... I had left the key position in parking... oi...
 

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If your carbs are set up right, the battery is fully charged, and you know you are getting fuel into the carb bowls. The only problem it could be is your timing. Either buy a timing light or rent one from Autozone or Advanced Autoparts if you think you are not going to need it again.
 

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There is a hole in the left muffler the size of a quarter were the muffler connects to the pipe. Putting my hand over the pipes i feel a lot more blast coming out of the right side. cranks and cranks but won't catch. Could this be a compression issue? a timing issue?[/I]
I found a website that says: "If you have a hole in the pipes, these bikes will not idle. Don’t even try to mess with it. It would be easier to teach a pig to sing." The website is called CL350 Tech tips.
 

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I'll definitely rent a timing light from autozone- great tip. I attached a picture of the tubes. Again, I'm trying to determine if the deep or shallow holes go in towards the body. there is a notch on either side for O-rings so it seems that they could go in either way. Attached is a picture


Ravenwoods-

I read the same tip yesterday- I think this is why i'm only getting a response from one cylinder and not the one that is connected to the damaged muffler. I tried to patch it with some tiger tape and it blew the patch right off. I'll definitely let you know if i'm able to get it going without replacing the muffler.



I appreciate all the help
 

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Honestly, if you are only running on one cylinder and compression is good, then you have either one or two problems. Either your timing is off or there is an electrical issue. Get yourself a good multimeter and check your ignition coils they should read in a certain ohm range, I believe they are 6 volt coils. Also check to see if you have a short in electrical harness.
 

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In the pic of the jets in the foreground; the one on the right is correct. The o-ringed end goes in first. The groove on the other end is for the spring clip that presses against the float chamber floor and helps to hold the jets in place. I am not sure from the pic of the jet on the left, but it looks right. Hard to tell with the blur, though. The groove holding the spring clip is sized differently on each jet and on the spring, so match the spring to the grooves.

The coils are twelve volt. Here is what I found when I was working on my 350: "By the way, for anyone else who has got one of these old CBs; I did find out what the reading should be on the primary windings (between the two small wires). I was having a hard time finding that out so I could simply test my coils; even Honda could not (or would not--they did not seem real interested in helping) give that reading to me. They should test at 4-5 ohms (Thanks to Bill Silver of Vintage Japanese Motorcycle Club). I got inconsistent readings on the coils on my bike, sometimes being right on and sometime testing wildy different, so there's another clue I am on the right track. I could not find what the secondary coil should test at."

Anyone here with a CB or CL 350 may want to read this trhead and learn from my (many) mistakes: http://www.motorcycleforum.com/showthread.php?t=93346

Cheers,

Mike
 

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Actually the coils are listed as 6 volt coils but should read in the 4-5 Ohm range. Honda will not give you that information as they consider it a trade secret. I guess they wanted you to go to the dealer to have the bike serviced. But there are ways to get that information. One way is to find a shop manual for that bike. By shop manual I am not talking Clymers or Chiltons. You want to find an actual Honda Shop Manual. If that doesn't work try to find a 70's or early 80's era Chilton Motorcycle Repair Manual. It is a huge book but it has all that information in it plus.
 
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