I know, I know, carb issues are the hardest for users to explain and hardest for forum "helpers" to diagnose which is usually why no one ever really likes to reply...or on the other hand...one will get too many replies which then can confuse the issue even more.
I have a '77 RD400 engine that was completely gone through by "Supertune" to include bottom end, bore, new matching piston set etc. Bike also has the 34mm Mikuni's with new manifold kit and crossover tube. Large Uni filters to boot. Older Neutronics (working condition) electronic iginition with Spec-II coils and pipes. (Lets keep the "get rid of the Neutronic's and Spec-II comments to a minimum please) Until I can afford or unless they are the culprits in my issue, those parts are staying put for now.
With both choke levers applied, the bike starts right up. OK guys, here we go!! Strap in!! When I take chokes off, something magical happens to the left cylinder.
It seems to stop firing. What I mean by that is the exhaust coming out of the pipe gets colder than the right side. When I pull the cap off the plug and get a minor shock through my body and then hold it close to the head fins, I can see plenty of spark. When I pull the cap while the bike is running there is no difference to the idle meaning only the right side is firing and burning the fuel. If I push the choke lever down a bit, the cylinder will start to fire back up.
I am "ass"uming that it is a carb issue...but what?? I have had these carbs off and on more times than I want to remember. I don't want to ride it and try to "blow it out" which I would also think could "blow it up" only running on one piston. Maybe a clogged pilot jet that would come to life when choke was applied? Now that would be an easy fix and maybe I should have checked that prior to sitting here typing all this up so you guys could laugh at me. If it warms up above 20 today, I might get after it.
On a side note, both choke levers point to the left on this bike. Should the right carb be pointing out to the right? Both slide cut outs are facing the rear and are timed as close together as I can get them. Do I have two left carb's...would that even matter?
I have a '77 RD400 engine that was completely gone through by "Supertune" to include bottom end, bore, new matching piston set etc. Bike also has the 34mm Mikuni's with new manifold kit and crossover tube. Large Uni filters to boot. Older Neutronics (working condition) electronic iginition with Spec-II coils and pipes. (Lets keep the "get rid of the Neutronic's and Spec-II comments to a minimum please) Until I can afford or unless they are the culprits in my issue, those parts are staying put for now.
With both choke levers applied, the bike starts right up. OK guys, here we go!! Strap in!! When I take chokes off, something magical happens to the left cylinder.
It seems to stop firing. What I mean by that is the exhaust coming out of the pipe gets colder than the right side. When I pull the cap off the plug and get a minor shock through my body and then hold it close to the head fins, I can see plenty of spark. When I pull the cap while the bike is running there is no difference to the idle meaning only the right side is firing and burning the fuel. If I push the choke lever down a bit, the cylinder will start to fire back up. I am "ass"uming that it is a carb issue...but what?? I have had these carbs off and on more times than I want to remember. I don't want to ride it and try to "blow it out" which I would also think could "blow it up" only running on one piston. Maybe a clogged pilot jet that would come to life when choke was applied? Now that would be an easy fix and maybe I should have checked that prior to sitting here typing all this up so you guys could laugh at me. If it warms up above 20 today, I might get after it.
On a side note, both choke levers point to the left on this bike. Should the right carb be pointing out to the right? Both slide cut outs are facing the rear and are timed as close together as I can get them. Do I have two left carb's...would that even matter?