Kev's O2 Controller on the T�n�r�
 

Fitted Kev�s latest O2 controller to the T�n�r� (when it was snowing a month ago) and have finally got a good few hundred miles riding in to evaluate things.

The bike already has the fuelling mod (set at 6) and DNA stage 2, which improved the flexibility of the motor hugely, broadening the spread of power, particularly in the lower revs on a wide throttle.


So what difference does the fitting the O2 controller on the Z (which doesn�t really suffer from the same surging issues of the R/X)? Well actually, quite a big difference � I was pleasantly surprised to say the least.

Most noticeable is the throttle response; snapping the throttle wide open (from a closed or small opening) at any speed is noticeably more smooth, linear and productive in terms of forward motion! Second is the fact it will now sit at a slow, leisurely cruise in traffic at say 2000-2500rpm without any sign of hunting � you can set the throttle position and the bike�s engine and road speed remain utterly constant. Fuel consumption, over just shy of 300 miles, appears to be identical to that before fitting the O2 controller (57mpg).

All in all, I�m well chuffed with the outcome (thanks Kev) � the T�n�r� is happier, both in traffic and out on the open road. Thoroughly recommend considering this mod whether you�re running a Kev mod or PC; more closely matched closed loop and open loop fuelling really does make a big difference.

Friend who scribbles for a well-known bike mag had a ride yesterday and said (I quote) � �That�s ****ing flexible for a single and keen to pick up off the throttle too � I really like it.�

Thanks for your detailed report, controlling both the closed & open loop circuits makes a big difference to the XT's ride no matter if the bike is completely standard or has filters pipes ETC.

Does that statement hold true with a PCV fitted Kev?

(Katy is due a tweak, been a while since I treated her,,, and me!)

Please tell me more, I love my XTX with the Kev fuel mod fitted so how much is the O2 mod???

I'll can have a shot at answering that...

Whether you've got a PCIII, PCV, Kev Mod, Nitro-X (or nothing at all) the air/fuel ratio will be stuck at 14.7:1 in the closed loop (unless of course you've already got the Dyjet O2 eliminator fitted). The problem is when you've sorted out the open loop fuelling with your PCV map to get a more respectable 13.2-13.6:1 there is a massive step in the mixture when the change occurs between closed and open loop; this is where the problems lie. By fitting Kev's O2 controller, which permanently fixes the ratio at 13.6:1, this step in fuel/air ratio between open and closed loops disappears, smoothing things out greatly.

It will definitely make a difference with a PCV as it will bring the closed loop fuelling much more in line with you map stored in the PCV.

Ta muchly.

Now, having both DNA S2, PC-V and the MTC single can, the bike runs very well from low revs. The MTC improves the low speed pickup immensely and allows better low rev performance.

It's probably worth my while giving this mod a whirl, just to compare results if nothing else.

Works perfectly with a PCV, been tested by 5 different guys on different Dyno's.:walk1:

Spot on I could have not explained it better myself.:laughing7:

That is precisely why I decided to do the O2 mod - as much out of curiosity as anything else.

Just waiting for the postman now.......:thumbleweed: