Triumphrat

ETxCruiser

06 America, 3800 mi.,AI and TOR exhaust are the only mods done.

At high revs while accelerating through each gear for 3rd through 5th it misses (sputtering) for a moment.

Anyone have any ideas as to where to start troubleshooting this issue.

danf_florida

Check spark plug gap (provided you are not hitting rev limiter). If you are running lean, plug gap could expand.

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2005 TBA, AI removed, debaffled pipes, added tach, leather saddle bags, backrest, and luggage rack, K&N Air Filter.

Verde

You sure you're not just hitting the rev limiter? It's set pretty low on the America. Take 1st and 2nd high enough up on RPMs to hit the rev limiter when you accelerate to see if you get the same feeling.

If that's not it and it's just when you're in the higher gears, aka faster speeds, then I'd jump on my favorite pet peeve since it gave me so much trouble... turbulence at the carb vent tube. In my case cruising throttle is where it affected me the most, not on acceleration, but I'm running pods and not the airbox. A quick check to see if that's the problem is to just pull the vent tube up until it's high enough to be well shielded by the engine case from wind and then see if it behaves any better. If so, trim the vent tube.

ETxCruiser

Thanks danf & Verde for your advice! Im not sure what "rev limiter" is. Is that something that can be adjusted or modified? Sounds like an intentional design to keep from tearing the motor up? Apparently I need to do a discovery ride to see if that is what is going on. Also will check into your other suggestions. Other than an occasional backfire when starting the bike and popping when in fast deceleration, it has been running good. Haven't had the bike long and am learning as I go. I realize it is not a sport bike but do like to think of it as a roadster vs sluggish cruiser. The missing or sputter does happen when I am accelerating fast and fully through each of the gears. I had not noticed it except in 3rd and 4th, but will retest.

Verde

You've pretty much got it figured out. Without going into too much of a description that I'm sure to get corrected on, the ignition control unit takes the signal from the pick-up coil and sends out a signal that makes the plugs fire at the right time. I'm pretty sure the way it keeps you in check is by not telling the plugs to fire once a certain RPM is reached, giving you that missing, sputtering feeling.

I can strip a wiring harness down to the bare minimum to make it run but I'd be hard pressed to figure out any re-programing. I havn't looked into it at all or paid any attention to the post about it, but from the background noise on here I believe there are high performance control units available that raise the allowed revs.

danf_florida

[QUOTE=ETxCruiser;1461034]Other than an occasional backfire when starting the bike and popping when in fast deceleration, it has been running good. Haven't had the bike long and am learning as I go. QUOTE]

Sounds like mine and I know I am running lean cuz I haven't yet rejetted (but still have not had any "problems"). Hint on decel popping, don't close the throttle. Keep it "cracked".

An easy way to check if running lean is to pull the choke open a mm or two.

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2005 TBA, AI removed, debaffled pipes, added tach, leather saddle bags, backrest, and luggage rack, K&N Air Filter.

Verde

danf, what mods have you done? Just TORs as well?

I finally put an air/fuel meter on on my bike to know exactly what was going on and found the stock carbs with K&N pods and TORs just cannot be tuned(by just jets, needles and mixture screws anyway) to avoid going really lean on the over run without being stupid rich for normal riding. I also found that most the decel popping happened when it was slightly lean, in the 14 to 16 range if I remember correctly, but on decel it wasn't uncommon to register up in the 19s with no tell tell popping.

I too sometimes pick a lower gear so I can crack the throttle a little on long descents. Sometimes on this bike, where I might normally let the engine slow me down some on an exit ramp or something, I'll just pull the clutch in and let it idle while I use the brakes. I'd rather replace some $30 brake pads a little early than run it lean too much.

chmeee5

I had TORs fitted with the EFI download recently and the throttle position on upward gear changes seems to be a factor for getting the 'pops'.

If I roll off the throttle a little too much or shut it off completely, then it will almost always pop or crackle - no snap as yet though

danf_florida

I have K&N air filter, AI removed, and a set of Chevy's debaffled OEM's. I check plugs for now, but plan on a rejet soon.

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2005 TBA, AI removed, debaffled pipes, added tach, leather saddle bags, backrest, and luggage rack, K&N Air Filter.

jimmy4871

These guys can mod the rev limiter and timing if that's your prob.


http://www.triumphtwinpower.com/triu...ccessories.php

Good luck

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When injustice becomes law. Resistance becomes duty.