Oilhead Timing the easy way

By: AdvWisdom
Title: Oilhead Timing the easy way
Sourced From: advwisdom.com/a/oilhead-timing-the-easy-way/
Published Date: Mon, 20 Jul 2020 00:36:05 +0000
Timing Adjustment – No Tools Needed
Well ok, not really no tools, but only two wrenches.

NO electronic tools needed, and NO electrical knowledge.

AND no need to remove the fuel tank.

Setting the timing uses a ‘feature’ of the 1150 Motronic ECU. It works on ’01 and ’02. But I do not know how widespread the ‘feature’ is across other model years.

Here’s the deal. You know how the crank pulley trips the hall-effect sensors right?

Well, if the ignition key is on, and the crank is turned slowly by hand, at the moment the crank pulley trips the hall-effect sensor, the Motronic will switch the fuel pump on for a moment.

Roughly the process is:

Ignition key off
Unplug the headlight
Remove the flywheel viewing plug in the bell housing
Remove the alternator belt cover
Rotate the crank by hand to the ‘ S ‘ flywheel mark
Turn the ignition key on – the fuel pump will cycle normally
Rotate the crank very s-l-o-w-l-y by hand until the fuel pump cycles again
(approx 5° of crank rotation)
The crank is now at the hall sensor trip point
Look at the flywheel marking to see where the timing is set
Adjust if necessary

Pictures and details to follow.

– Jim


Poolside 05-11-2005 03:07 PM

Tools needed

Turn the ignition off.

Reach up under the instrument panel and unplug the headlight. This step is optional, at your discretion. I prefer to unplug the headlight. If a timing adjustment is performed, the ignition key will be on a while.

Remove the black plastic front engine cover. Behind the cover are the crankshaft pulley, hall effect sensor adjustment, and alternator belt tension adjustment.

TIP: If an aftermarket shock is fitted, the shock may be too close to the front cover. If so, the lower mounting bolt may be removed to tilt the shock out of the way of the front cover. If a stock shock is fitted, there is enough clearance to remove the front cover.

IMPORTANT: Think about this. If removing the lower mounting bolt of the front shock, be sure the rear of the bike is weighted so that the bike will not tip forward. And, it helps to have another person to lift up on the front wheel to remove the shear load from the shock bolt.

After the front engine cover is removed, replace the shock bolt for safety.

Rotate the crank until you see the ‘ S ‘ flywheel mark in the bell housing hole. For clarity, this picture is staged with the technician on the left side of the bike. You may find it easier to do this from the right hand side of the bike.

Rotate the crank until you see the ‘ S ‘ flywheel mark. The ‘ S ‘ mark is 5� Before Top Dead Center (BTDC).

Turn the ignition key on. The fuel pump will cycle normally. And if you unplugged the headlight, the headlight will not be on.

S-L-O-W-L-Y rotate the crank. After about 5� of rotation the fuel pump will cycle again.

You can see that 5� is not very far. If you ‘feel’ that you over-rotated the crank by some amount, just reverse the crank 5 degrees and try again. This is a light-handed maneuver.

Take a look at the flywheel mark again. If the timing is correct, the ‘ OT ‘ mark will be lined up in the center of the viewing hole. The ‘ OT ‘ mark is Top Dead Center (TDC).

Ok. Repeat the last two steps a few times. The fuel pump will cycle each time the crank pulley crosses the sensor trip point.

Each time the fuel pump cycles, stop and look at the location of the flywheel mark. Slowly repeat the process of crossing the sensor trip point, and checking the flywheel mark. After some number of tries, the final location of the mark will be consistent.

The flywheel mark will be in one of three places. Exactly on TDC, somewhat ahead of TDC, or somewhat behind TDC.

PARALLAX ERROR: It is easy enough to position your eye exactly centered above the bell housing hole. The hole in the bell housing has side walls or ‘draft’. And it is easy to spot whether your perspective is lined up.

From a look at the pictures below, it is possible to determine that the camera lens is not lined up with the centerline of the hole. The camera lens is a little above the hole centerline.

What gives the high lens location away is the ‘draft’ visible along the bottom edge of the hole. Eyes will see the same thing if their perspective is a little above the hole centerline. Get your reading glasses, and a good light.

When your eye is lined up with the hole, it is natural to draw an imaginary line through the center of the circle. Take a look at the green line, is very natural to see where the ‘ OT ‘ mark is, relative to that imaginary green line.

Spark advance looks like this. Some amount ahead of TDC.

For example, this is what 2� advance looks like.

Spark retard looks like this. Some amount behind TDC.

For example, this is what 2� retard looks like.

The hall sensors are hidden from view. They are behind the crank pulley. The hall sensors are mounted to a circular plate. The circular plate can be seen around the perimeter of the crank pulley.

Spark timing is controlled by the hall sensors. Spark timing adjustment is done by changing the position of the hall sensors, relative to the crank pulley. Changing the position of the hall sensors is done by adjusting the circular plate.

The timing adjustment range is limited to about �5�. And about the middle of the adjustment range sets the timing to about TDC.

Loosen the THREE hex head fasteners that hold the circular hall sensor plate. Fully loosen the fasteners so that the circular sensor plate will slide freely.

People have reported that the plate on their bike was stuck in place or almost impossible to turn. If that is the case the fasteners can be removed fully and the plate can be freed by lifting it away from the surface. Some canned air and spray lube should remove any grit or debris, and keep the plate moving freely when loosened next time.

It is much easier to make small adjustments to the plate if the fasteners are very loose. If the fasteners are even slightly snug, too much force must be applied to the plate to move it. And when it does move it will overshoot the intended mark.

PAUSE: This just seemed worth stopping for. I did not really notice until working with these pictures. This is the UNDERSIDE of the front control arm. I am glad my friend lets me use his bike for these photos. My hands (and the camera) stay clean.

Adjusting the timing.

First, turn off the ignition key.

The timing is adjusted by moving the hall sensor plate. The full range of adjustment is limited to about �5�. The sensor plate can be moved to either end of the 10� range and the engine will start and the bike is plenty rideable.

Make a pencil mark across the plate and front cover and experiment. I am running mine at about 3� advance timing. The idle is smoother and the pinging is about the same. Though as the weather gets warmer the engine may ping less at 0� timing.

To advance the timing, move the bottom of the hall sensor plate to the right. A small flat blade screwdriver is used to slide the plate.

To retard the timing, move the bottom of the hall sensor plate to the left.

After moving the hall sensor plate where you wish, snug one of the fasteners to hold it in place.

Turn on the ignition key and repeat the previous steps of rotating the crank pulley until the fuel pump cycles. And check to see how the timing changed.

After all of this smooth sailing, there is one pesky gotcha here. When reattaching the plastic cover, it can sometimes be impossible to get the screws on the left side of the cover started.

Here is why. The oil return tube has two brackets that are held in place with two of the front cover screws. You can see the problem you will have if the brackets are not lined up with the screw holes.