I will unfortunately have to make this a bit lengthy to pass all pertinent information...
I am now $420 in the hole trying to fix a problem with my 08 America. From time to time, the bike runs like crap, like it is either starved for gas or is way too rich. I have to rev way up to start out to avoid stalling, can't shift beyond 4th gear without stalling even at 55 mph. Smells of gas when running and the MPG goes from approx 45 to 30-35. Further, I am beginning to get discoloration at the pipes due to this.
Have had it since May of 2011, bought used from a Triumph dealer and before taking had the TOR long pipes put on it to replace the stock pipes. I asked the dealer to adjust the carbs for the pipes, they did not tell me what they did to set it up. It ran perfect from May until some time in late November for about a 1000 miles before I first had the issue.
Taken it to two shops already, the first, a Triumph dealer (not the one it was bought from) cleaned the carbs, adjusted fuel/air mix and replaced the fouled plugs ($300). They never gave me a straight answer regarding what caused the problem. Did note that it now has a 42 pilot jet and told me that a 40 is stock. They suggested a jet kit but did not indicate that the lack of a jet kit was the problem with it running poorly.
Following this, it ran fine for about 4 days and began the intermittent issue again. I then tried smaller shop and they tightened the intake clamp and adjusted the fuel/air mixture ($120). The mechanic mentioned that the air injection tubes were capped. Apparently this is a common modification made to help the bike run better? Anyway, he did not suggest changing it.
Well, it ran fine for about 5 days until today and I had the issue again!
No rhyme or reason to when it happens, cold, hot, after it has ran for a bit, right at startup, it will sometimes resume running well after having the problem at startup, etc. No patterns at all. Further, it either runs 100% fine or has the issue, no in between. When I am going down the road while it is running bad and it reverts to running ok, it occurs in a split second and will generally run fine until I shut down. After setting, it may run fine or it may have the issue again at startup.
Wondering if anybody has had a similar issue with a carbureted twin Triumph (02-08)? Any suggestions are welcome. I will contact the second shop tomorrow. The most frustrating thing is that it only occurs intermittent so perhaps the mechanics have not experienced it run like crap. It is miserable to ride and I am causing the pipes to discolor so WANT IT FIXED!