Set Timing instructions

[pswanson]

Can someone please direct me to a previous thread describing how to check and adjust the timing on my 89 R100RT? I haven't done this yet, but I hear it's good to do before balancing the Carbs. I've recently done everything else -- valve clearances, air filter & oil change etc. How adjustable IS the timing on the electronic ignition system? My wife seems to have thrown out both my original manual and my Clymers, in preparation for her divorce initiative.

Paul

[20774]

Something to read here...not sure the level of detail regarding specific instructions for setting the timing...

http://bmwmotorcycletech.info/Ignition.htm

[pswanson]

Cool. Thanks. I still need a reference to instructions on setting timing. I didn't see it at this address.

Paul

[20774]

I don't own one of these, but I looked at my Haynes. For checking, the best way is to use a timing light. Haynes seems to discourage trying to check things statically.

If it needs resetting, Haynes says "The procedures for checking and resetting the ignition timing of the electronic are similar to those described...for the later type of contact breaker ignition." I believe they're talking about the "bean can" edition which was introduced in 1979-1980. To set the timing on those models, you open up the timing chest cover (disconnect all battery grounds first) and loosen the screws that hold the round unit tight to the timing chest. This unit should be cylindrical in shape. Start the bike and using the timing light, turn the unit to set idle and, better yet, make sure that full advance shows up in the window, probably around 3000-3200 RPM. Once set, tighten the screws.

If there's problem with erratic timing or it won't adjust, then you have to get into more tests of the timing unit and/or the ignition module.

Seems straightforward... Try an advanced search on the Airheads forum for "electronic ignition" or "ignition timing".

[BeemerDave]

Paul
1 Disconnect Battery
2 Remove front cover
3 Mark beancan position
4 Loosen two screws till bean can will Rotate
5 Put beancan back in orig. position
6 Hookup timing light to left plug
7 remove timing hole cover
8 Reconnect Battery
9 Start engine, don't need full warm up
10 With timing light aimed at hole rev engine till timing stops advancing. Take quick look at tach should be about 3000 rpm.
12 Rev engine to a little over where it stopped advancing. Point timing light at the hole Z mark should be centered in the timing hole
If Not Grow a third arm and hand!!
13 With engine revving and timing light on hole rotate beancan till Z mark is centered.
14 Shut off engine
15 Snug up beancan screws
16 Disconnect Battery
17 Replace front cover
Done

BeemerDave
83 R80RT

[pswanson]

Awesome, thanks. Seems straightforward,
Paul