My mechanic was telling me the other day that some tuners advance the timing too much trying for better numbers, then bikes have trouble with pinging. I'm not a tuner though, so all i know is what I'm told.

 

IMHO you want the bike tuned for 13:1 across the board.

Do you have a dyno available to sniff it ?

The bike night I go to has a dyno come in at least twice during our 18 week season. Best 25 bucks I spend is to have the bikes checked to verify any tuning I did over the winter was done right.

Right now it looks like my ZRX might be a tad rich, as I lost 3 hp when it was dyno'd at 70 degrees compared to 86 degrees 6 weeks ago.

 

Advanced timing will cause pinging however if it just happened all of a sudden I am more inclined to believing an 02 sensor failed or a sensor of some sort isn't adjusting the fuel mix properly. Does the tuner you have read and clear cel's. I would return the bike back to the stock tune and see if the problem persists.

 

You're not gonna like this either but a straight AFR across the board is a rookie tune or at least an easy money tune for the operator. Based on your symptoms, and description of the condition, at 13:1 you might have carbon build up that has raised your compression and reduced your resistance to detonation, just a possibility. Check cranking pressure and compare it to when the build was first done. Good luck, let us know what you find.

 

Ok guys thanks for all the input it was intake seals leaking ,replaced and all is well.

 

There is a lot of confusion on this topic. Here is my attempt to simplify and explain and probably confuse as well! Ok, here goes....
The ECM is the brain of your fuel injection system and lives to control the amount of fuel being delivered at any time by the fuel injectors. It does that by referencing stored tables (maps) in its memory as well as the 9 different sensors that feed into its decision making process. Incase you are interested, these sensors are: Throttle Position Sensor, Manifold Absolute Pressure, Bank Angle Sensor, Intake Air Temperature, Engine Temperature, Vehicle Speed Sensor, Crank Position, Ion Sensing System, Idle Air Control

There are 3 tables that the ECM uses constantly, the VE tables (one for each cylinder), the AFR table and the Spark Advance table. I'll explain how these work in a sec.
There are other tables that are used in special conditions, the Cranking Fuel table, the Warm-up Enrichment table, the Idle Rpm table and the Intake Air table. The ECM knows to use these from the input from those 9 sensors i.e. when it detects really low rpms it knows you are cranking the engine and goes to that table.

So your engine is running and here is how it works. The ECM reads the VE tables constantly, using throttle position and rpm to know how much air is going through your engine. Then it uses the manifold pressure and intake air temp to understand how much oxygen is available for each cylinder. Then it goes to the AFR tables and based on load and rpm, reads the right AFR value and know how much fuel to inject to achieve that AFR. At the same time, the ECM reads the Spark Advance tables to send the signal to the coil.

The much talked about O2 sensors are a tail-end minor adjustment to the ECM in closed loop operations designed to maintain a 14.7 AFR that is considered complete combustion.

So the bottom line is, since the entire deal is based on the ECM knowing how much air is passing through your engine and the VE tables based on a set configuation (engine size, exhaust, throttle body size, air cleaner etc).....when you modify your setup beyond say slipons, you have to adjust your tables.

 

and then there's the buisness of physical head engine temp and air intake air temp. a lot going on for sure.

 

Lets start with the year of the bike we're talking about. If it's 2009 or older, we're talking AFR, if it's 2010 or newer we're talking Lambda.

Either way, no matter what you read on the internet, there is no such thing as the "right" AFR. Mine is all over the place, depending on load and RPM. So when you say that yours runs around 13~13.5, is that what your main table is showing in all the cells? If so, your tuner ripped you off. There is no reason whatsoever to run any richer than 14.4 or so at cruise. Keep the bike in closed loop for cruise, and you'll get better mileage. Fatten it up at WOT (I'm in the 12s there).

 

Here's a screen shot of what I set the AFR potion of the MAP to when I am done tuning a bike. This is a creen shot from super tuner, but the same holds true for TTS. The Red cells are were I leave the bike in closed loop, it will allow the ECM to make minor adjustments for you. You will notice as the RPM's and the load increase I have it set so the bike runs richer.