R1100 GS - low octane fuel question
 

Hi,
I'm just re-igniting this old thread. Some good info here but I'm wondering if any new experiences or info can be added.

http://www.horizonsunlimited.com/hub...injection-4317


Does anyone have any experience of how a fuel-injected BMW R1100GS will run on lower RON fuels?
I will be taking a British spec bike to Sub-saharan Africa next year. Many of these countries use 88RON and even lower.
I use a K&N air-filter but the fuel injection, air-induction and combustion systems are standard otherwise. Should I get the bike retuned before I leave?

The linked thread suggests not but I'm wondering if the K&N filter makes too much of a difference.

It was mentioned in the thread that 'low octane' ignition rotor can be fitted.
Any thoughts? Experiences? Is it worthwhile? Is it worth keeping the bike in standard tune until I reach Africa and then fitting this rotor.

Lastly, swapping internal fuel filters to external.
1), Is removing the internal filter straight-forward?
2) Can I use a standard generic in-line fuel filter or do I need anything specific?

Your 1100 will run down to 80 octan at least. Not a problem since good 'ol 1100s are still relatively low compression (10.3:1) engines with very robust configuration.

In South-America I've run 80-87 octan often when other wasn't available. In Iran I had to run 80 all the time, since there wasn't much else availalbe outside bigger cities. I guess this "80 octan" was even mixed with something sometimes to make more money out of selling bigger amounts of fuel :rolleyes2:

Engine will make more valve noise under high load (hard accelerations, overtakes, hillclimbs etc), but it'll deffo keep you going with any kind of "dirt" you put inside :thumbup1:

For me K&N filter - not really worth its hype after long testing it and in the beginning I liked it (saving me fuel 0.1-0.2L per 100km was the best thing about it). Your engine may have premature wear running K&N in a long term. I used to run K&N at home, switched back to regular OEM paper for our RTW expedition currently going (over 60 000km this trip, bike's now over 144 000km). If you plan to trash the bike in less than 100 000km then I guess you're fine with K&N, if longer than that, at least use a good self-made oiled pre-filter with K&N or switch to OEM paper filter is the safest option to avoid premature top-end overhaul because of more engine wear (with better flow and more dirt geting into the engine with K&N). Sahara - I wouldn't even dream of using K&N with all that sand in the air. Put the stock OEM paper one, if the engine starts to smoke coz of clogged air filter, take it out, kick the sand and dirt off hitting it agains something gently and put it on again and continue - at least it keeps your bores clean while they do hard work 4000+ hits per minute each average :)

Route the fuel filter outside the tank if possible and carry always a spare one. So if you get a really dirty fuel that clogs your fuel filter, just swap it for a new one. Placing the external fuel filter with R11xxGSes is a bit hard tho - I found a good space just above the end of telelever wishbone (where it attaches to the engine), glued some rubber foam layer onto telelever so the filter doesn't scratch it while it moves.

But that said, on short trips even into Sahara you'll probably be fine with the bike as-it-is - I haven't gotten a dirty fuel anywhere in the 3rd world years of travelling - so you must be very unlucky one and it's easily doable when it's still inside the fuel tank as well, just a bit more hassle.

Hope this helps, Margus

BMW has done a good job with their engineering. In Mexico, last January, I had to run low octane (was it 87?) because nothing else was available. BMW says that "performance may suffer" in the owner's manual, but the only thing I noticed was the fully loaded bike did not accelerate or reach high speeds as easily as when using higher octane. :mchappy:

Great info guys!!!
I really appreciate it.
:thumbup1:

Safe travels!

I live in Brazil, and fuel here is just rubbish mixed with anything you can think about, from water to alcohol, including solvents. You´re lucky if you´re able to find 85 octanes fuel. Had many BMWs in the past years, now I ride a R1200GS, and all of them had no problem at all with fuel. Ran just fine, and no special tune ups required.Cheers !