Motronic and chips etc.

[Taipan]

Hi All,

I have bought a s/hand Lazer exhaust for my 1100GS which I would like to fit asap. But I dont want to fit it without altering the fuelling to suit it. So, I have been trawling the archives and reading up on this. But, there is a lot of (conflicting?) advice out there. I'm trying to get my head round the tuning/remapping side of these bikes. I know there are different EPROM chips available for the GS such as the ones on Ebay . But I think I'm right in saying, the EPROM chip loads its its maps with the instructions given to it from the relay (which comes in different colours) in the fusebox.

I believe you can make up a jumper lead and experiment with different settings as seen in the picture below. But does the settings in the picture relate only to the BB EPROM chip fitted, or does it alter the motronic the same way with the OEM chip fitted, albeit different versions of the map? Does that make sense? What i mean is does the OEM chip have several map variants installed, like the BB chip? Can i just install a jumper lead with the OEM chip which will code the motronic for a bike with an aftermarket exhaust? Or do I have to change the chip to get the correct map?

Many thanks.

 

[Telford]

It is only really safe to assume that the BB chip jumper settings apply to the BB chip - until you have some documentary evidence to the contrary!

I have an 1100 with BB chip fitted - now running on std collector and silencer with no cat and I'm using the Std Bike settings as in your picture above.

The BB programs are to cover different states of performance enhancement, the standard, OEM, chip has programs in it to enable different configurations of machine to be shipped - e.g.

With CAT
Without CAT
With CO sensor
Without CO sensor
Ultra low octane fuel

And, probably, combinations of the above. But essentially with the same cam/compression/exhaust.

From my reading, an 1100 with cat has 30-87-87a linked
1100 without cat 30-87a

So the BB "standard" settings use the same jumper settings as OEM 1100 without cat. The BB settings corresponding to OEM with cat are marked as open race muffler (which I used with the Remus Race) SO NO ASSUMPTIONS CAN ME MADE.

What are your current jumper settings?

I believe if you have NO jumpers set you are in a default "should be safe" mode which assumes 1.8%C0 (Carbon Monoxide) open loop - a bit more fuel than with a Lambda or CO sensor in the loop - with potential for cat wrecking.

So where does that leave you? No wiser I think (just like me).

To be absolutely sure, fit the laser, get it dyno'd and emissions tested for peace of mind.

If it were me, I'd fit the laser, get the engine warm, take it for a good thrash and do a plug chop. Repeat for the three OEM settings above (i.e. no jumpers, 30-87a, 30-87-87a) and decide which (if any) was correct.

If the plugs look good - great, if they're a bit 'sooty' you've probably not thrashed it enough or you've got too much fuel - which is erring on the side of safety but not green. If they're white you've either thrashed it too much or you're lean - which could hole your pistons if not corrected.

It works on the old bikes - if its lean, raise the needle, if it's rich drop the needle - lovely things carburettors - slide cutaways, pilot jets, needle jets, main jets, float height - so many things to play with.

If nothing is satisfactory - I'd then get a chip.

 

[Taipan]

Thanks for the reply. I'll fit my Lazer on Saturday and remove the CP thing. I think i'll get a chip off the guy on ebay and get it dyno'ed to be sure.