Never had any problems with my 998 with the 54mm system and ECU

I think mine has a 54mm system & ecu too (I say 'think' as the box the standard pipes are in says 50mm on it, but the previous owner said it was a 54mm he asked & paid for). Also has the air restrictors removed.

It doesn't do it all the time, and I did wonder if I picked up a dodgy tank of fuel. It has done it on 3 seperate occasions now though. I also think it is running rich as last week in the hot weather on overrun or very slight throttle off it would pop & bang like a goodun (the french villagers loved me ! :D ).

Hopefully a new set of plugs and the pc will fix it, but just thought I'd ask.

Cheers,
John.

The 998 uses the Weber-Marelli IAW 5.9M ECU, a 32-bit processor about the size a stapler that no longer uses a replaceable EPROM chip. Unlike the 996's 1.6M computer it (presumably) is designed to fire twin injectors sequentially.

Interesting that Shazaam. It looks the same as the ecu on my ST4S (2 big square connectors and mounted down by the battery).

I was told you can't chip these, and the DP kit for the ST came with a complete new ecu rather than a chip too, as did the 998 as the standard ecu is in the box with the standard pipes.
So does that mean the 998 shouldn't suffer the problems you mentioned due to short duration injector firing ?
Interestingly I'm sure the details for the pc say to unplug one pair of the injectors.

Sorry, this is starting to head off topic.

You can't do anything with that ECU, it is mapped according to the pipes I guess, but every bike is different, I think my 54mm ECU was labelled 996R54 or such like...

I doubt there's much you can do yourself, the obvious answer would be a PCIII and get it set-up correctly, but that's not cheap.