Smoke coming out of carbs

[Tertle_Power]

So I've posted a couple times with my bike lately because it has been a pain. I just installed a new dyna s and since installation i can't get it to run right. I have spark going to all for cylinders, but only 1&2 are firing, 3&4 are cold. It runs better at higher rpms with no load and dies at idle but the headers from 3&4 are still cold. It will shoot flames out of the exhaust on that side when I fire it back up (with a loud pop because of the un-burned fuel) and sometimes it will send exhaust backwards through the carburetors. Is my timing that severely off? Is my cam tensioner worn out? If anyone has the slightest inclination to what is wrong, please help.

 

[Guest]

You have to answer two questions. Did it run ok before installing the Dyna? If yes, then you might have the timing off. Also check to see if your plug wires are routed correctly. 1-4 and from one coil and 2-3 from the other. My guess is they are routed to the wrong plugs. Other question is have you checked and adjusted the valves lash? If yes go back to the timing if no then see if you have some valves then are tight, but my guess is there is something wrong with the coil plug wire routing.

 

[Steve]

Have to completely agree with Rick on this one. :encouragement:

This is a strong argument for "only change ONE thing at a time". That way, you know whether it worked or not. If it didn't work, you know what changed.

If the bike ran before, and you only changed the Dyna, that is your problem. If you also moved coil wires (removed the plugs?), you don't know if it's the coil wires or the Dyna. If you also did something with the carbs, you add a THIRD uncertainty, and the list keeps growing.

In stock configuration, the left coil fires cylinders 1 and 4, the right coil fires cylinders 2 and 3. It's nice to know that you appear to have spark on all four, but it needs to happen at the right time. Have you checked the timing with a timing light?

We are suspecting the coil wire swap because you are grouping cylinders 1 and 2, then 3 and 4. There is nothing that happens naturally that has these groupings.

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