K11 Owners Group

[Freedom45]

If there are archives on this subject, please advise. The "search" engine didn't turn up information, or, I don't know how to search properly. The question remains.

Can advancing the timing be beneficial? I am aware that timing is done from #1 cylinder relative to TDC. But, has anyone had experience in slight advance of timing, good or bad. Last week I replaced the Hall sensor and I was simply wondering.

Thanks for your information.
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1996 K1100RS SE, K1100K, K75S, Laverda 1200
MOA 9900
IBA #70 NRA

[old guy old bike]

I don't consider timing a power adder. You can move the power around a little bit without drama. Advance gives you bottom end but takes away from the top end. Retard it a little and it will mellow the bottom end and give you a little more gusto on the top. All in all, factory settings are most likely the best of both worlds.

Also, you will probably notice more heat in the motor from advanced timing and also may need to go to a higher octane fuel.
Jeff
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1993 K1100LT
2003 K1200GT Gone but not forgotten
2014 Victory Crossraods

[Glen]

About 6 months ago i did stumble on to a web page where there was a complete article including graphs of what happens when you advance the ignition timing of a K 1100 bike. I don't remember the website url or the numbers.

The summary went along the lines of " Advancing the ignition timing has shown ( using graphs ) that this is one of the few things easily done that will add some performance to the bike".

It also stated once you decide to run at this level of advanced ignition that the only fuel you should ever use is premium quality high octane and that BMW probably chose the safe timing option as touring riders tend to end up in the middle of nowhere looking for any fuel available.

cheers

[Freedom45]

Thanks for the viewpoints expressed. I suspect a good solution would be to make a dyno run at factory spec and with a two degree added advance. That might be expensive and leaves me with a "seat of the pants" approach.

I always use premium grade gas, preferably Chevron. But, sometimes one may encounter no choice but regular and that hasn't been a problem so far.

Fuel mileage is always another factor. Many of the roads I ride allow for 80 mph travel, sometimes more. The K1100RS tends to run smoothest around the 90+mph range. At those speeds I get an average of 40 mpg whereas sedate riding in the 60 mph range will see an increase to the upper 40s. If an advance in timing improves mileage, so much the better, but, I wouldn't appreciate a decrease.

Ah, time for a good test.
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1996 K1100RS SE, K1100K, K75S, Laverda 1200
MOA 9900
IBA #70 NRA

[old guy old bike]

Perhaps you would want to consider retarding the timing if you are spending most of your time in the upper reaches of the power band.

I don't know if a timing change will help the MPG because the injectors are controlled by the Motronic.
Jeff
_________________
1993 K1100LT
2003 K1200GT Gone but not forgotten
2014 Victory Crossraods

[Freedom45]

Thanks Jeff

Your comment may be correct, however, I've equated slight advance with added performance, not retard. I'll certainly post my "unofficial" results in a week or so. I'm putting the new Hall Sensor in tonight and will time the ignition as soon as I get my dial gauge back.

Having grown up with coils, distributors and points on older Beemers, I am aware that the complexity of today's computer management systems may not respond well to tinkering. But, oh boy, do I love to tinker.

FWIW: my Hall sensor burned out due to the wiring cracking badly in several places. Now I ponder how to best isolate those wires from heat..
_________________
1996 K1100RS SE, K1100K, K75S, Laverda 1200
MOA 9900
IBA #70 NRA