Topic: major problems????

[cwalsh540]

alright here we go-

-1973 cb350 four
-went from stock to-
   -dyna s ingnition
   -accel non cdi type coils
   -new plugs and wires
   -4 to 1 exhaust
   -rebuilt carbs
   -form 75 to 100 main jets
   -single air filters
now, all electrics work, timing is dead on(checked staticly), engine cranks fine, but not starting and backfires. could it be the carb adjustments? it cranks for a while and then BOOM!

PLEASE HELP. VERY FRUSTRATED!

thanks
chris

[mk0094@hotmail.com]

if it is backfiring and not running, the cam shaft could be off 180 degrees, allowing it to fire when the intake is open. i had that problem a while back. make sure the camshaft is alligned properly.

[kghost]

Well maybe not the cam since you may not have had the head off.

But what about plug wires? You got the leads to the coils hooked up right? if not and you're backwards you'll get the condition you are describing.

[cwalsh540]

thanks guys....but you were both kinda right. so i put on my old coils and the same thing, checked the timing 100 more times then just thinking thing through i realized that some IDIOT(me) had the wires swaped at the coil wires into the harness.  sooo stupid it could have been running hours ago....i guess if you cant laugh at yourself, who can you laugh at

[jbailey]

Once you get it running, do yourself a favor and set the timing with a timing light.  I set mine staticly and find that it is usually off several degrees.  Since there are no degree marks, I can't tell exactly how much.  It doesn't make enough difference to really tell by riding, but it is usually off retarded.

[kghost]

Do I win a prize? 

Actually I'll just be content if no one asks how I know about swapping those leads. 

[dusterdude]

kghost,we cant let you be content now can we.so cmon and tell us how you know.

[kghost]

My only reply would be this........

You can also assemble the advance mechanism 180 degrees off too.......

 

Makes it really really hard to set the points.

[77F2cb]

On the 750, Dyna instructs you to time it at the "right hand" advance mark.  I do this "statically" by holding the timing cam (round magnet) clockwise in the fully advanced position, until it's right.  It can be a little hit and miss, rotate the plate, check again.........checked while holding in full advance, and the light comes on at the right hand advance mark.

[Tim2005]

And now it's running, what's it go like, especially at full throttle? I'm just thinking that 100 main jets are pretty huge, I'm more used to 400Fs and on them I'd be looking at something around 85s with a similiar pods/pipe set-up.