Running on one cylinder cb350

Jramos13

Been Around the Block
If there was show called my build from hell my bike would be on it.... :'(

Anyway after sorting out my electrical and carb issues, a new problem arise
On idle im running on the LH side only, the RH only will fire if i hold the plug cap close to the plug but not when put it in completly. If i try to accelerate with the plug put in i can hear the RH carb choking and the bike would stall if i dont let go of the throttle, if i accelerate really slow then it will accelerate fine, the rpm hangs on the way down.
I already tried swaping the coils, plugs cables and boots from RH to Lf and i get the same result so the coils are good, i have Viets ignition the rh is a bit earlier than the lf but he told me that its normal and they do em like that for easier starting
 
Silly question, but did you check the spark plug? I always try to remember to check the easy stuff first.
 
i thought of that too but i switch the coils and cables from lf to rh and the same thing happens,
 
Honestly sounds like you might have a short somewhere. I've seen this on cars before. You've moving/adjusting the plug cable as you hold it away from the plug... either that or the plug and that single cap aren't connecting where they need to connect. How far away are you holding the cap for it to work? Did you try JUST moving the plug wire to the other side?
 
if i unhook it and leave it in the plug about 1/4 of an inch out it will fire the plug, what i did was change the coils cables and plugs cables with boot to the opposites sides and the same thing happened i did noticed at improvement in the first start up but then it died again on the rh side

i was having problems with my electrical wiring, but it turned out it was the bulb was 66/55 and was drawing way to much current, i disconnect it and the battery was charging at 14v again. plus before trying anything today i had the battery connected to the tender last night till it was charged
 
Jramos13 said:
yea it has 2 coils, its a 1972

http://www.honda350k.com/CB250_350.jpg

Based on the wiring diagram all I can see inline that might affect it is the emergency switch might be faulty or the contact breaker. Or based on the diagram they could be improperly grounded... not sure but i'd check everything in line and leave the plugs and wires and coils alone for now. Try up or down line from them.
 
those were removed since the wiring was made from scratch, i have a 12v+ directly to the coils from a fuse box, if it went out the LF wouldnt fire either, but now that you mention it i still havent cheked the actually plug outside to see if it fires with the cap in securely, if ti does fire, then the issue might be something with the carbs?
 
Jramos13 said:
those were removed since the wiring was made from scratch, i have a 12v+ directly to the coils from a fuse box, if it went out the LF wouldnt fire either, but now that you mention it i still havent cheked the actually plug outside to see if it fires with the cap in securely, if ti does fire, then the issue might be something with the carbs?
Wiring made from scratch eh? This makes a bell ring for me. Status of the fuses? Do you still have a valid ground, any pinched wires? (inspect all the damn wires... or by pass your custom wiring with a new wire for the faulty side.

If you're not getting spark on account of your carbs - you're doing something wrong.
 
for the ground i have one of those car ground cables that they sell at autozone with the big terminars, from the bat Neg. to the frame and i have good continuity in all of the grounds, the positive is the same cable for both coils, i just chek it and its not pinch or broken anywhere, if it were the LF coil wouldn't fire either, regardles ill try what you are suggesting running a cable directly from the battery positive to the coils to see if that helps somethings,
 
Re: Re: Running on one cylinder cb350

Jramos13 said:
those were removed since the wiring was made from scratch, i have a 12v+ directly to the coils from a fuse box, if it went out the LF wouldnt fire either, but now that you mention it i still havent cheked the actually plug outside to see if it fires with the cap in securely, if ti does fire, then the issue might be something with the carbs?

sounds like you're flooding that side, and that's why it's not sparking. pulling the cap away from the plug increases resistance, producing a stronger spark, which is able to overcome the over-rich mixture. I would clean your plugs and go back to the carb set and sync.
 
that sir, makes sense too, ill try that and set what happens, ill bench sync the carbs again and the set air screw, what makes me think is the rich mixture, the carbs were set pretty nicely and this happens all of the sudden,
 
Jramos13 said:
that sir, makes sense too, ill try that and set what happens, ill bench sync the carbs again and the set air screw, what makes me think is the rich mixture, the carbs were set pretty nicely and this happens all of the sudden,

Rich is probably a lot smarter than me when it comes to this stuff and his idea makes sense too... I'm a troubleshooter by nature and just laid out the things I would've tried before messing with the carbs. Good luck!
 
Could be timing too - how far off the mark are you on that side?
 
in the static timing with the engine off, when i get LF exactly on mark, F is here:

null_zps72320e21.jpg
 
I don't know where the timing mark should be on the CB350 - where should the mark be at TDC?
 
TDC is LT in the tick mark, the photo doesnt show the tick mark very well but its in the middle of the coil prong thing next to the F (hope that made sense),

if its an overly rich mixture should it go away once i accelerate? because this happens mostly at idle, once i accelerate it misses sometimes but it runs
 
I just finish charging the battery and it is at 13.05v right now, ill meassure it tommorrow to see if its holding charge
 
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