Triumphrat

VS

Hi all...I was just wondering about the symptoms of improper mixture adjustment. A few weeks ago I had the AI removed by my dealer, and since then, a few things have been different. First, it seems the bike isn't quite as torquey (especially in 2nd and 3rd gears) as it was before the AI was removed. It's not a huge difference, but it's big enough to notice. Second, every once in a while I get a backfire when starting the bike cold, which is something that never happened in the first 1000 miles with the AI in. Finally, when starting the engine warm, the engine sort of "stumbles" to life--like it amost doesn't start, but then picks up at the last second. Again, this is a definite change post AI removal.

From the research I've done, this sounds like it could be a fuel mixture issue. Any thoughts? Also, if this is a mixture issue, I really don't have the tech know how or equipment to fix it, which means a trip back to the dealer. Any idea how big a job this is to correct?

Thanks for any advice you can provide.

MOBRIT

VS,
Not that I'm a very knowledgeable mechanic, but the first thing I would do is pull the plugs and have a look. I would expect a dark or blackened electrode if it's too rich, and a nearly white electrode if it's too lean.
There are lots of guys on this forum that can help with possible jetting solutions, if needed; but they will need to know all of the details of the bike, including all modifications.
Good luck with it.

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'He was out of Luck when Luck was doin' alright.' John Hiatt

vertwrks

in my understanding lean will surge and rich will fumble. This is if the mix is off pretty far. Like MObrit says you can pull a plug. For mainjet reading you would want to run it WFO for a bit and shut it down coasting to a stop and then pull the plug for a more accurate look see, kinda old school. Best yet find a dyno and pay the man.

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04 Bonneville w/904 kit, 1mm over valves, ported, ARK'd, Bub's, HSR 42's, F3 forks, kyb rear shox, F3 clip ons, Brembo M/C, 6 pot caliper, 17" Excel's, this & that

Motolink

When I removed the A1 the bike ran as good as before. I sounds a little like there is a air leak, take it back to the people who did the job and have them check the rubber grommets for correct sealing.

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A1 removed, R&N filter, Poloris bellmouth, Thruxton needles, Baffels removed, 19T, Bellacorse Western bars.

johnyC

VS,

When the AI is removed a hole is left in the airbox which needs to be plugged, or the bike will run weak. The kit comes with a stopper which should have been fitted by the dealer. Take a look at your airbox and see if the plug has popped out.

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johny. the boy's happy, leave him alone.

RedBird

I agree with the last two comments above. I wouldn't recommend trying to read the plugs--very few experienced mechanics can properly read plugs burning unleaded fuel. There should be NO noticeable difference between performance with and without the AI. Take it back to the shop that removed the AI and have the problem corrected. If the airbox plug is missing, I would suggest using silicone sealant when installing a new plug. Also, the vacuum cap (for the left intake manifold nipple) supplied by some of the vendors are not of the same quality as the stock Triumph vacuum caps. In other words, the vacuum cap will deterioate rapidly and fall off--order some vacuum caps from a Triumph dealer.

Larry

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Larry
2003 T-100 (790cc), NARK, NH Togas, 8100 rpm rev limiter, 158 main jets, 42 pilot jets (less than 1 turn out on pilot screws), stock needles--no shims. 13 A/F ratio from 1100 rpm to 4000 rpm; 12 A/F ratio from 4000 rpm to 6000 rpm; 13 A/F from 6000 rpm to 8100 rpm.:D
2007 Tiger 1050--White:D--SW-Motech crashbars, Skidmarx rear hugger/chain guard, Calsci +7 windscreen.

VS

Thanks, everyone. I'll definitely head back to the dealer and have it checked for an air leak. It sounds as though that's the problem--I took a close look at the red rubber caps they installed after the AI removal, and when the bike's running, one of them (on the right side) looks like it's barely holding on--like it pressure underneath is trying to inflate it.

Thanks again.

357Bob

As for your question of being too rich or too lean. If it is too rich it will run better cold than when warmed up. If it is too lean it will run bad when cold & better as it warms up.
Or is it the other way around? Just kidding.

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357bob

MOBRIT

Maybe not specific to this thread, but the notion that one can't read rich vs lean plugs with unleaded fuel is certainly not correct. There are many good bike mechanics that will pull the plug first and look at it for this info. In my Norton, with Amals, the tolerances are not as fine I'm sure; but it's not at all difficult to see rich vs lean, or fouled plugs. And it uses unleaded fuel-has for many years. I just ad Marvel Mystery oil to the petrol.
Bob

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'He was out of Luck when Luck was doin' alright.' John Hiatt

RedBird

Bob,

That's what I'm talking about..."pulling the plug first" tells you nothing about what's going on except at the last few minutes of idle before the engine was killed--and then only if the plugs were new. New plugs, proper plug chop at the correct rpm, AND the knowledge of where to read the mixture ON the plug itself is a requirement for this endeavor. I have seen very few "mechanics" that can do this...before and after unleaded fuel. The problem was worse before unleaded fuel because everyone seemed to think they knew how to do this when in actually they were making most of the same mistakes that are made today. :-D

Just my opinions and they are worth less than nothing. :-D

Larry

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Larry
2003 T-100 (790cc), NARK, NH Togas, 8100 rpm rev limiter, 158 main jets, 42 pilot jets (less than 1 turn out on pilot screws), stock needles--no shims. 13 A/F ratio from 1100 rpm to 4000 rpm; 12 A/F ratio from 4000 rpm to 6000 rpm; 13 A/F from 6000 rpm to 8100 rpm.:D
2007 Tiger 1050--White:D--SW-Motech crashbars, Skidmarx rear hugger/chain guard, Calsci +7 windscreen.