Fitting the DNA stage 3?
 

I've just come across a question which I thought I should put out to you guys.

When fitting the stage 3, do I keep stage 1 and 2 as well?

My dealer's technician just asked me if it should be stock cover, since the stage 2 pulls in too much crap.

I also have the restrictor which I never used.

Any thoughts?
Power commander and dyno run tomorrow!

Yes (if you want full power). If you've got a PC and you're getting a custom map built on the dyno*, you should have no problem with fuelling.

Not sure what he means? The stage 2 top is less likely to let things in than the stage 3 side cover will, and even then the stage 3 is only going to be a problem if you've wading in deep water? Neither is going "pull in" crap if the filter media is correctly oiled and doing it's job.

Forget this - may as well sell it on. No need for it with correct PC map.

*DON'T FORGET - Block your AIS before the dyno run (if you haven't already). If you don't the AF ratios read off the dyno will be all over the place.

Hello Sir,

Thanks for the reply.


So I had a bit of trouble with my dealer and time scales... only had a few days in which to get it all done so we went ahead with fitting the PCV and Stage 3 filters without blocking the AIS.

Their technician seemed to be knowledgable about lots of things, regarding the PCV. He said my compression ratio is between 12.9 and 13.4 : 1 which he reckons you can't get close to on any other bike without spending thousands. Sounds about right?

He said I could remove the AIS completely, and put a consumer (resistor) across the sensor, saving about 1.5kg. Also sounds right.

He gave me an airflow chart, but not the A/F chart.
He said that the AIS blocking is not essential, as the PCV only reads airflow at the carb, and that the AIS takes air away BEFORE the carb?

Can you explain why we need to block the AIS? I'm not quite sure I understand that.


I had also ordered an Exan exhaust from Mad4Exhausts... I think they're all on holiday in Italy as I haven't heard back from them in two weeks!
Wanted to get this on at the same time, but for the meantime sticking with my De-cat stock exhaust (heavy b*stard)



I think when I have another couple of days spare, I'll fit the exhaust, block the AIS and then get another run on the Dyno to sort this out.



A couple of differences:

Bike ROARS through 1st, 2nd, and 3rd. Front wheel up in 1st, that was unexpected!

4th and 5th gear seems a bit more 'chuggy' than when I had the Stage 2 & Kev Mod

Drinking fuel a bit more, but maybe this is the fuel indicator being a bit over-sensitive... Ran 60 miles into F-Trip and still only put 19 litres in.


Is it worth the ~�1,000 i spent on the PCV, DNA Stage 3, Exhaust and fitting?

We'll see!

the AIS lets air from the air box into the exhaust to burn any un-burnt
fuel that enters the exhaust...
the dyno takes the AF reading from the exhaust so any air the enters the exhaust will increase the 02 in the exhaust gases & give a higher 02 level that the dyno will be reading..
block it off to get a true AF reading...

But doesn't the O2 eliminator negate this?

I guess I won't know until I actually do it.

Fitting the DNA stage 3?
 

As Pete says, the AF ratio is measured with a sensor inserted in the tailpipe. If the AIS is connected, it will bleed fresh air into the exhaust under certain conditions which will kid the dyno into thinking the AF ratio is too weak. However, what makes it worse for building a PC map is that the AIS won't bleed air in all the time, so the dyno AF ratio readings will be very erratic and thus, so will your map.

The only way to get the right data is to block the AIS.

The bike's O2 sensor's readings are only used by the ECU in the closed loop, plus the bike's ECU knows when the AIS valve is open and when it is closed and can read the lamda signal accordingly. The dyno can't do this and will just read a sudden rush of weak AF ratio in the exhaust when the valve opens and a spike of richness when it closes; in other words it won't have a clue what's going on! ;)

Block off the AIS otherwise you are wasting your money on a Dyno tune, with the AIS unblocked your map will be 100% wrong in the areas when the AIS valve opens, I can now see why your Dyno tuner says he can't get a good map this is because he does not know what he is doing.

I only use Dyno's that tune using Tune Link tuning software, this software can build a perfect PCV map in half an hour.

I'll second the fact he clearly doesn't know his arse from his elbow! ;)

Neither do I, clearly...

~Lucky I've got you guys around!

Thanks Kev, Pleiades and Petenz.




Booked in and should be sorted by next week before heading off to Ireland!

Ah, but you aren't being paid to know - he is, that's the difference! ;)

Hope you get it sorted...