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Discussion Starter #1 (Edited)
Hey all, I just recently purchased a '71 cb350 with 13,000mi and am in the process of getting it up a running. I did a bunch of work on in so far in the last month i've had it and ill list below all thats been done:

1. Fully rebuilt both carburetors (previous owner siliconed them shut...) _Static and progressive syncs :thumbsup:

2. New points (figured thats a necessity with the unknown previous work done on it) _Set ignition timing and point gaps :thumbsup:

3. New spark plugs and boots (set gaps to spec) _before change, left plug had ALOT of carbon build up on it! (Not reaching self cleaning temp--cold exhaust)

4. New Petcock (old one had no restriction of fuel regardless of position)

5. New condenser ('cause why not?)

6. New AGM battery (will be sitting mostly in the winter months until I crack the piggy bank open and move far away from the immaculate roads of NJ)

7. JB welded a pinhole in the gas tank (once again...previous owner had a failing relationship with silicone...)

That about sums up the work I've done so far...Now the issue is that the bike isn't starting up! Just a side note, the bike started up after the very first thing (#1 rebuilt carbs), but after I realized the LEFT EXHAUST WASNT GETTING HOT AND PUTTING OUT THE PRESSURE THE RIGHT ONE WAS, I installed new points and set timing (all good!) but you can probably guess what happened after that....ever since I've been scratching my head.

*My Electronic start isn't that reliable at this point. Some times it catches other times it just free spins until it slows and stops on its own. So before when it did run (although cold left exhaust)...One kick--started....One push of the e-start--started.

Fishing for a some ideas on what it may be that is preventing the bike to start...
 

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Did you pull the plugs, put them in the boots ,lay them on the engine and check for spark?
 

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Discussion Starter #4 (Edited)
LOST CAUSE: New condensor, but not new coils. If i have to replace the coils I will, but I'm not sure if thats the issue yet. The bike was running before points were changed, however the left exhaust was cool to the touch after idling awhile, so the reason for tackling the points. Old spark plugs especially the left one had a lot of carbon build up (no. 3 on the list in the thread post). Replaced with new plugs.

CB350(K5): I have not tried that yet. Will try this afternoon and post results.
 

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LOST CAUSE: New condensor, but not new coils. If i have to replace the coils I will, but I'm not sure if thats the issue yet. The bike was running before points were changed, however the left exhaust was cool to the touch after idling awhile, so the reason for tackling the points. Old spark plugs especially the left one had a lot of carbon build up (no. 3 on the list in the thread post). Replaced with new plugs.

CB350(K5): I have not tried that yet. Will try this afternoon and post results.
Sorry totally missed that.

Note it is normal to foul up plugs while adjusting carbs and setting timing. So be prepared to go through several sets of plugs and dont freak out like i did when they foul! : )

Sent from my SM-G930V using Tapatalk
 

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The easiest way to troubleshoot whether it's electrical or fuel is to spray some starter fluid through the carb and see if the bike fires. If not then it's elecrtical. Maybe your wiring or point setting/timing.
If so then check the carbs again, and all that jazz

Edit: and you'll want to service your starter clutch
 

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Discussion Starter #7 (Edited)
Getting spark from both plugs. I didn't have the boots tight enough to the wires. Sprayed fluid into carb and it didnt start. I guess ill go back and address the points timing again to make sure both are timed perfectly.
 

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Discussion Starter #8
So I have spark, ignition timing is set, battery is fully charged. Should i look at my carburetors again? The only reason I ask that is because after i rebuilt the carbs (new jets, float, seals and o-rings) the bike started with one kick. And did so until I went and changed the points because i felt the left exhaust wasn't putting out the pressure the right was. Plus points were a little rusty, so i figured it wouldn't hurt. Now theres not even a glimmer of it starting up regardless of what i wrench on.

I'm without a doubt very new to engines in general, I've been doing my research, however i have a looooooong way to go.

Advice is greatly appreciated.
 

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So I guess my best recommendation at this point is to just start at the beginning and go through a thorough tune up

Set valve clearance
Set cam chain tension
Redo the point gap and ignition timing. Remove the advance mech and make sure your cam shaft pin is at 6/12 o'clock with the LT cyl at tdc.
When setting timing, set on the compression stroke... Which is just after the intake valve closes. Wrong stroke and it won't work.
Make sure the correct coil and points are plugged into the correct condenser wire.
At this point you can retry the starter fluid or try and fire it up.
Also you should check compression, especially on the LT cyl
 

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Did you accidentally reverse the Connections for the points when you replaced them?
 

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Discussion Starter #12
Got it up and running doode! Went from the beginning and set the cam chain tension, adjusted valve clearance then finally set the points. This morning I was thinking it was going to be a frustrating day after not hooking up the other side of the fuel leveler hose on the bottom of the tank and losing all the gas on the ground. After several kicks it fired up and now the next project to tackle is figuring out why the idle is not consistent (ie. builds up to 2000, then down to 1000, sometimes choking out). It doesn't happen fast just over a bit of time. If I leave it idling without giving it alittle throttle once in awhile it'll for sure choke out after about 3-5min.
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