Hi Simon.

Why do you say that the Tuninglink on the dyno cannot simulate very little load at very small throttle openings? You can easily adjust the PID inputs to simulate almost any type of acceleration and amount of load applied.

I agree with you to not allow Auto tune to tune at the lower RPM ranges and to restrict how much it will adjust by.

Time after time Auto tune gets those settings wrong with riders complaining that with time it just gets worse. The dyno on the other hand seems to be getting it right. All of them claim the low end with small throttle openings are so much smoother, more responsive and throttle response is improved.

I agree with you that it can simulate any conditions but not all, on the Dyno it's virtually impossible to match the on/off small throttle and variable road speed conditions that most people encounter with day to day riding.

You can improve the surging problem as Kev says by chucking a load of fuel in low down but it only masks the problem.

There is a problem with the XT part throttle fuelling that can't be cured even with a power commander and a skilled dyno operator, if there wasn't Dynojet wouldn't waste time developing an 02 controller for it in the first place.

Richard and Martin at Dynojet UK have spent a lot of time on the dyno trying to cure this problem and failed and they've both got degrees in some sort of Electrical engineering and they train all the Dyno operators in the UK so should know what they are doing.

Dynojet haven't exactly rushed to bring this new controller on to the market as they don't have the problem over there in the US.

Dynojet we are waiting.

Freez I have been using Tune Link for a while now.

I also agree with Simon by adding fuel low down, masks the problem for the 07 onwards XTX/R's.

Come on Dyno jet we need your help.

If I remember rightly one of the responsible men of the tech department of DynoJet USA joined our forum a little while ago. I need to dig out and search his username, perhaps one of you can pm him asking for more details.

I was only half right, we do have not one but 2 DynoJet geezers on the forum, one from the states and one from UK here are their usernames:

Dynojettech is the american one and europeanbob is the UK one.

Feel free to contact them by pm Kev and see what they have to say.

Thanks

I contacted Dynojettech the day he joined the form via PM, he did not return my PM. You know I contacted Dynojet a week or 2 back & there reply was no one knows what is going on with regatds to the O2 controller.
:hippy2:

Great! What hopes do we have? After all why joining this forum in their respective work position and not even attempt to provide any assistance?

Like I said, I don't have anything against the Auto tuner, I recommend it to people but it is something you need to be careful with as users can cause a lot of problems for themselves if they let the unit go wild. I just don't advise people to use the Auto tuner and think it eliminates a good dyno tune to start with.

The other thing I maybe need to understand is what is the 07 XT's are doing and what are people complaining about? Still a lot of surging?

Another thing we need to try and see if we can figure this out is to see if we can hook up the PC5 to detect what gear the XT is in. I think that is another big problem why the Auto tuner is not getting the mapping right. The bike will have different amounts of load, depending in what gear the rider is in and that in turn has an effect on the amount of fuel required or the way the bike breathes.

Another interesting thing I read the other day. I was reading up on some engine development work they did on F1 and on the Pro race bikes. One of the tests showed cylinder pressure changes at a fixed throttle input and RPM.

I was shocked to see how the pressure varied between strokes. You would imagine that since throttle input and RPM is constant, pressure inside the combustion chamber should also be. Not so.

Things just get worse with a single cylinder motor, especially at lower RPM where breathing is even more erratic.

If pressure changes from stroke to stroke, then it means the amount of air flowing into the motor is also not constant and that in turn means fuel supply has to be adapted at a very rapid rate.

If I map low end, small throttle openings on the dyno with tuning link it takes 5 to 20 seconds easy to tune just one of the hundreds of RPM/Throttle settings and that is with constant load and a fixed throttle input in a controlled environment.

Auto tune uses the same probe, so no wonder it never gets the low end right, because things never remain constant for 5 to 20 seconds to allow the unit to sort the fuel out.

You will need a much faster lambda sensor and method to adjust the fuel supply that what currently is available to sort that problem out while you quickly pop through the gears.

Ok then...

In laymens terms then please...

How... can I use the autotune efficiently, to create a good map?

i.e. recommended settings, RPM, throttle openings.

As for visiting a dyno... as far as I'm aware, and according to the dynojet website, I do not have an approved dynojet testing centre anywhere near here! Hence why I bought the autotune. Not forgetting aswell, dynojet states that the autotune is good for users who aren't able to use a dyno which is the main reason I bought it.

I was on the phone last night till after 1100pm to an engineer in Greece, he deals directly with Dyno Jet, with the development & testing of their products & has done alot of work with the Auto Tune. He agrees with Freez that you should get a base map made on a dyno then use the Auto Tune from there if you are having problems.

He did say (as Freez mentioned) you need to be very care full with the Auto Tune, one can mess the mapping up very easily.