Bonneville America Forums Forums Technical Forums Performance Mods Disabling the O2 system

Wayne from Tuneboy has sent me a Tuneboy tune that disables the O2 sensor.

Anyone know of any negative consequences of running the bike with AI still intact but without the O2 system?

I will be installing this tune today - and will post an update.

The upside is (hopefully) the elimination of the snatchy throttle that many of us Effies experience if we are running with Triumph's TOR/aftermarket map.

BTW, Wayne believes that Triumph have only 2 maps for our bikes - one for stock pipes and one for TOR. There is no difference between the TOR map and the supposed aftermarket pipe map.

Ok ... first run with the modified tune which has the O2 sensors disabled and is slightly richer than the factory's lean settings.

Overall performance is very responsive to throttle - a bit more than stock. Very smooth at all throttle positions.

Snatchy throttle was occurring going from 0% throttle to 20% throttle using the Triumph aftermarket pipes map, making slow speed maneuvers difficult. This snatchiness is reduced by at least 50% with the modified map and is much more manageable. I very happy about that.

Popping. Still popping but maybe less loudly. Popping seems to be worse on a cool engine and the engine was already warm during my test run. We'll see tomorrow. I actually don't mind a bit of popping.

So far no downside.

Richard, try putting a 17mm ball bearing in the hose that runs from your airbox up to the AI. This is effectively the same as removing it but leaves all the hardware insitu.
See if that reduces the popping.
Are you running the tune from my bike?
The one on his website for speedmaster, pod filters+custom exhaust+02 sensors disabled?
Steve

Hi Davo.

No, it's not your tune but probably based on it. I told Wayne I wanted to reduce the snatchy throttle and run a little richer from the lean factory setting. He sent me a modified 20184 called: 20184TuneMod1. I have your tune but I haven't tried it because of course my AI is still intact.

I will leave it that way I think (intact AI) until this issue of a possible pre-cat in our headers is resolved. Apparently there are warnings that disabling our AI could cause this pre-cat (if we have one) to melt down sooner or later and block our headers.

I have had my whole system ceramic coated, Definately NO cats.
I have done 6000k's since my mods and the remapping, everything is perfect.

Hmmmm. I suspected as much. Some have said all EFI bikes have pre-cats in their headers but the source was in the UK according to the rat forum.. So I suspect only Euro and US bikes have them. They are even identified in the specs of their T100 owner's manual (UK & US).

QUOTE:
"Page 99 specifications - emissions control Equipment - type - Twin oxidation catalysts and pre-catalysts - which is what Triumph tech dept Hinkley described to me"

Whereas our owner's manuals omits this.

My 09 book has "Twin catalysts with pulsed secondary air injection" as the emissions control equipment- on page 88.
Just as a picky point, the uk and us can't be the same book, we measure the octane amounts in petrol differently to the us. So it maybe they have different emmisions control too. They definately do for the california models.

Steve, what are you riding? I'm curious as to why you got your headers ceramic coated. If you're riding an America/Speedy the double skin on the headers eliminates blueing pipes - so why the ceramic coating?

Because it looks badass and won't peel eventually like hi-temp paint.

if wayne says iots ok i would take his word for it. he does great stuff for the rockets and i am sure he will be just as good for the new bonnies

My pipes were statring to blue, even with the AI removed, I didn't mind the look of it but the black ceramic fitted my bikes theme a touch better.
My understanding is AI produces more heat. So even if you had cats or pre cats I don't see how they would suffer from less heat, it may effect how quickley they reach operating temprature? Not sure , I personally am a dog person and don't see the need for cats on anything

Yeah thanks Frank - I'm sure you're right, and Wayne has been great with support and answering my dumb questions.

Maybe I'm cautious but we are exploring uncharted waters for our bikes and our knowledge of EFI. Steve's leading the way but our set-ups are slightly different and there still seems to be some doomsayers out there regarding EFI custom tuning and pre-cats etc.

BTW - I am happy to share the custom tune that Wayne from Tuneboy designed for me. It is based on the Triumph aftermarket/TOR tune but is slightly richer and has the O2 sensors disabled to reduce snatchy throttle syndrome. Anyone who wants it shouild PM me with you email and I'll send it to you.