R1100S Ignition Timing

motoyoyo · 08-05-2010, 08:59 AM

I'm expecting my new Hall sensor assembly and will need to set the ignition timing. I have searched the entire forum and have not found any info on how to do this. The factory manual shows only partial information and leaves the rest with the factory BMW MoDiTeC instrumentation.

I am just looking to set the timing to factory specs and not really interested in experimenting with different settings. Should I consider using a timing light in some way or should I be measuring a certain distance btdc of the piston and rotate the hall sensor until it sets off an led indicator light? I have a dial indicator that I can make an extension pickup for, but I have found no specs to go with.

Here is the page from the factory manual:

jduke · 08-05-2010, 09:48 AM

Timing light won't work, something about the computer advancing or retarding the timing depending on load, or something like that...
Mark the position of the old sensor and line up the new one and see if that works.
I've seen posts on other sites where they've made a some kind of tester where they hook it up and then gently move the HES until the light comes on which means it's in the right position.
But where I saw it I can't remember or find, sorry.

motoyoyo · 08-05-2010, 11:35 AM

From the info provided about the hall sensor replacement it appears that the sensors are set to activate at TDC. Not sure if this is correct or not. There sure isn't much info to go on.

jduke · 08-05-2010, 11:44 AM

I found what I was looking for.
ADVrider - Timing Adjustment - No Tools Needed

Here are the instruction to make your own timing box, hope this helps.
http://users.rcn.com/dehager/service/oilhead_timing_box.pdf

Steve Carlton · 08-05-2010, 11:50 AM

Call Chris at SJBMW. I'm sure he'd be happy to advise you.

motoyoyo · 08-05-2010, 12:10 PM

That post from Advrider makes good sense. When the hall sensor is not working the ignition and fuel pump are both affected. Having the fuel pump triggered at the sensor activation point should be just as good as an indicator light. That is also the first time I have heard to use the "S" mark on the flywheel. Sounds good, thanks.

pmc847 · 12:27 PM

I just tried this ADVrider - Timing Adjustment - No Tools Needed
. It works on my 04 BCR.

I did notice that timing is a little advanced if idle rpm is about 1,000 but steadies up at 5deg at about 1200. Then it starts it's normal advancing as RPMs increase. YMMV

jduke · 08-05-2010, 12:16 PM

Send Bob Hancock a donation to the Mike Kelly fund if you can.

RBMann · 08-06-2010, 09:51 AM

Glad someone posted that because I remembered it triggered the fuel pump but not what the setting were.

motoyoyo · 08-06-2010, 12:48 PM

From the AdvRider article it was a bit unclear what the actual factory setting should be on the timing. I was able to make a temporary repair in my stock hall sensor plate and put it back in to see where it had been set. I had marked the plate to the case so it went in aligned the way it was before. With the key on and rotating the flywheel, the fuel pump came on at exactly TDC. I'm fairly certain this is where the factory settings should be set.

The new hall sensor plate did not have the fancy shielded wire bundle and weather tight fit like the old one did. All the wires were loosley held in an unshielded wire covering similar to shrink wrap. There was not even any attempt to make the ends water tight. If I had to do it again I would certainly have attempted a repair since the workmanship on the new part is nothing special. I will repair my old hall sensor as a spare.