Low octane fuel + exhaust modification

Hi everybody,
Over the winter I'd like to prepare my 2006 650GS for a longer trip across Asia and both Americas. Obviously there are areas with sh..ty fuel. I'd like to ask here about some stuff:

1 - when changing exhaust for a non-cat one, is there any additional change to electronics needed (lambdas etc...)?
2 - what is your experience with electronic devices changing the fuel mapping for low octane fuel ('Performance Controller' from Wunderlich or others)? Is it a must for areas with 80oct and lower or has anyone driven through these areas without any modification?
3 - how much will the using of bad petrol change the consumption and performance of the GS?

Many thanks!

If leaded fuels are to be in the diet, cat must go. Best mod for digesting poor quality fuels would be dropping the compression ratio either with different pistons or thicker cylinder head gaskets..

suggestions for you

If changing the exhaust, I'd suggest a Staintuned- Single pipe.
It just slips on to your existing downpipe where the pipe sweeps upwards past the pillion foot pegs.
The lambda sensor is retained- no need to change anything there. You might need an exhaust sealant paste like Firegum to make a good seal at the joint. If fule is really bad, you can add an octane booster but...you'd need quite a lot- heavy and of course very flammable! You can always pick up soem fuel injector cleaner somewhere and run that through to clean up.

(Single pipe frees up space on the right hand side of the bike for you to perhaps put a storage canister- very handy)

TIP: Take a small funnel with a wire filter in it and use whenever you feel the pumps/barrels look old and use it to get rid of any debris before they enter your fuel tank. BM wobble-U bar-steward filters are very expensive. (I took off and cleaned my fuel tank when I came back and you would not have believed the ' mud' that what was inside it!)

No need to change anything else. & no need to change electronics- the less the better! the 650 is a lot of bike and frugal on fuel (except in sandy bits!). You might want top change the standard spark pluf to an NGK Iridium Spark Plug . I have noticed a quicker/cleaner throttle response. I don't know your mileage but you might want to change the throttle gear wheel if its worn- cheap enough to do.


I actually ran leaded and rubbish octane through the standard exhaust for 9000 miles in Africa- granted, the power was a bit down eventually as it clogged up and it did not do the 'cat' any good ! hence the Staintune mod. on my return.
Very simple to do.
Have a great journey

Many thanks to both for your advise!
I'll probably go for Remus (I like the look of it ) The one side solution is sure very practical, but I cannot find any 'Staintuned' dealer here in the Czech Rep..
I was glad to read that actually, it is possible to drive with no special mod for low octane, however, I drove across Middle East this summer and local fuel (<88oct.) made the bike sound differently (sort of dry noise...) which did not make me feel comfortable.
So is here anybody who has experiance with the mentioned electrical devices to change fuel mapping?

Many thnx!

also put a paper fuel filter in line with the expensive BMW pressure regualting filter. It saves having to change the expensive one out.