Bonneville America Forums Forums Technical Forums General Tech 03 america strange intermittent miss- help!

Sorry to only post when I have a problem.
03 America, stock except a few holes drilled around baffels in exhaust.
Got the bike back around May. It started to only start on right cylinder, but then when warm the other cylinder would kick on. About a month ago started it up, let it warm up, drove it up the road, and for the first time started to have a miss, Stopped at a stop sign, it died. Started it back up, after about 30 minutes it ran fine then. Got on it again yesterday, and the miss was back. It would miss only under slight throttle, once it was reved up in any gear it ran fine. After about 45 minutes riding it was like a switch and it started running fine. then today, cranked it up, and again same thing. I have heard not to, but I unplugged the plg wire from the coil on the left side and it runs fine on just the right cylinder. I put new plugs in when I first got it, ngk iridium, and has done fine until now. Any ideas? Left coil, left carb, cdi? Thanks for any ideas or help

it's your CDI. replace with Procom unit or with a Firestarter from Triumph Twin Performance.

I was afraid of that. I think I may swap the coils around just to see if maybe it is the coil. I would much prefer 75 as opposed to close to 300.

Yupp, like he said. way too intermittent for a coil. There's a thread about the Firestarter CDI somewhere around here, it has just two settings, Clark Kent and the Man of Steel setting whereas the Procom un it has 9 settings and they just be all over the place. Post the classifieds for a stock CDI.
And it's OK to post just when you has the problem, we be mature here and it's like havin' a kid that only calls when he be in jail or need some cash.

"And it's OK to post just when you has the problem, we be mature here and it's like havin' a kid that only calls when he be in jail or need some cash.

+1 Like it.

Any thoughts as to which one is better? I will probably never do the airbox mod, although I would like to completely debaffle the pipes, which probably would require rejetting. I have read on here and other sites the Pro Com can be a little cold natured. I will check ebay and craigslist. I think TTT has the firepower for around 260 or so and british customs has the pro com for about the same.

I have a Procom ignitor that I would consider selling, it's on my bike now, has been trouble free for many many miles. I don't have any computers that are Windows based, so I can't tinker with the programs anymore. They are not Mac or Android compatible, but they are easy with a Microsoft computer. Shoot me a pm if interested, I might get the Firestarter myself. My stock unit runs awesome, it just cuts off at 7400 rpm so that's why I went with the Procom in the first place.

Can anyone direct me to how to adjust the air gap on the ick up coil after you remove the cover? Maybe their is already a thread about it, with pictures hopefully.

You need a manual, many things are relatively well explained therein. So, buy a replacement gasket, pull the right side cover. As to how to set the gap, with a metric feeler gauge ascertain your gap between the rotor and the pickup, if out of spec, slightly loosen the fastener, using your feeler, adjust as needed, retighten and check again, repeat until all is correct. Be careful not to scar the engine case and cover doing the re install prep clean. The fit is usually good enough, no gasket goop is needed, but if you want, black silicone will suffice, I use just a little where the wire enters the case, the rest of mating surfaces I leave dry, your call on that. Replace cover, land and start all the cover bolts, finger tight. Using a torque wrench tighten fasteners to 15% less than spec in a star pattern, then do the final torque up, star pattern.. BTW, you will only lose a little oil in the process, with bike on its side stand, so you can just top the level off if you keep the operation clean or change your oil, again your call.

The early bikes have the breather issue to contend with (it's in the manual), & an impact wrench will help loosen the Torx fasteners without buggering them up.

I don't mind the spoiler, what issue is there with the breather? Could it be causing this issue?

not likely, it's on the other side of the engine

I have the old style engine and never had a breather issue. The pick up adjustment is self explanitory once you open the cover, if it isn't you probably shouldn't be in there. Oh and get a brass feeler gauge.

I seem to be in a lot of places I am not suppose to be. Ha. This weekend I am going to swap the coils and then go from there. Hey, who needs a manual when you guys are here!

the comment about having an impact driver for the pick up screws is right. Those suckers are TIGHT. If no impact driver use and extension with the bit on it and put the bit in the screw and give it a couple sharp smacks with a hammer. This will make them easier to break loose.

Switched the coils today. All symptoms went to the opposite side. I guess I will be ordering new coils. Thanks for everyone's help!

Put new coils on. That fixed it! Thanks everybody!