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Re: [ST] CO level, bad mileage, rough running



- ----- Original Message -----
From: "Steve Bergman" <steverayb@xxxxxxxxx>

> Ok so since the last ride of the year last fall I have
> been getting a lowly 32 to 35 mpg.  Right away this
> spring I took it down to Team Triumph of WI & Todd
> hooked up to the "gameboy" and noted that the CO level
> was extremely high & also noted that I did not have
> the latest tune.  So he downloaded the newest tune &
> reset the CO level.  It takes him a couple of trys to
> get the CO level right & it never really seems to hold
> steady.

If the mechanic was only using the 'gameboy' to set your CO level, there is
no chance that it is set correctly.  The CO reading must be taken using a
calibrated exhaust gas analyzer (EGA), and the 'gameboy' reading is only an
arbitrary number (ie. it does not represent the CO percentage and the
readings will vary from bike to bike)

>
> Last week I notice that the bike seems to be running a
> bit rough (more than normal) at low speeds when trying
> to maintain a steady speed.  So I head back down to
> Janesville & Team Triumph.  Todd again notes that the
> CO level is very high again, test drives it & confirms
> that it is pretty choppy at low speeds.

The CO setting should not drift like that.  So either your mechanic needs
more practice or there's something else wrong with your bike.  If it turns
out there is something else wrong, and since the CO setting is taken at
idle, I vote for the idle air control valve as being another suspect, but
I'm sure others will pipe in with other suggestions.  I also think the
throttle bodies have to be aligned, or synced, or whatever before you do the
CO adjustment, which, by the way, should be 3.0%.

> Tonight I start the bike up and it is even more rough
> than usual so having just read the recent post about
> resetting its brain by turning the ignition on and off
> several times I try it just to see what might happen.
> On my short ride after that it seemed to be much
> smoother.
>
> So what the heck is this all about?
>
The ignition off/on routine is most often used to cure a very specific
problem that manifests itself as a loss of power and a complete refusal to
idle (revs must be kept up around 2k to keep the engine running).  Only one
off/on cycle is required to rectify the problem, that is until the next time
the symptoms occur, which could be days, weeks or months.  The good news is
that this problem seems to occur on relatively new bikes and seems to go
away by itself (at least it did on mine).  I don't think it sounds like
you're having this problem.

If the CO is high, as suggested, that means that your engine is running rich
so that will affect your mileage, but I don't know by how much.

For now, if I were you, I'd concentrate on getting that CO level set right.

Hope this helps
Neil



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