compiled & edited by Kristian #562
Please read the Disclaimer before attempting any work in this FAQ.
Photos from Flash #412


Ron Woods Timing Key Installation

(Also useful for Details on Flywheel Removal & Reinstallation) - Anyone have any more Photos for me PLEASE.?

by Kristian #562

I installed it myself and took it out myself. It's not rocket science, but you need to be a little bit mechanically minded AND have a couple (at least ONE) BMW Tools.

Tools: You will need




As you can see from the pictures above, there is a cut-out in the Normal Woodruff key, across about half the width of the key. The key sits in a slot on the Crankshaft on the RHS side of the engine and the Flywheel/Magneto sits over the shaft. The Flywheel/Magneto’s location, with respect to the shaft, is governed by a slot along the inside of the Flywheel. On the outside rim of the Magneto is a little magnet which when it rotates past a pickup (Magnetic Flux) fixed to the Crankcase, generates the Energy for the spark. So now imagine first the normal key sitting in the shaft and the Magneto sitting over the Shaft and fixed in location by the Key. Imagine the Piston is some way, but not too far, past Top Dead Centre (TDC). Now if you make a cut-out at the rear of the key, you can then rotate the Magneto with respect to the shaft, by 4 degrees (Of course this depends on the cut-out). This will rotate the Magnet on the RIM forward of the pickup. Now if you fix the Magneto onto the shaft in this position, when you rotate the engine such that the magnet is at the pickup, the piston is just past TDC when it fires and supposedly more energy is imparted to the piston, partly due to greater compression at firing and partly because of the longer stroke

The cut-out also make the key WEAKER, so make sure you LOCTITE the Magneto/Flywheel onto the tapered spindle properly or it will shear off. It has happened to some people.


Installation Sequence:

Some of you may disagree with the order I did things in, but I did it this way out of sheer laziness and not wanting to drain my (just changed) oil. It was OK, just a little messy. Those who have to change the oil or want to do it the right way can drain the oil from Both Reservoir and Sump, but that's another story.

Note, if you didn’t elect to drain the oil first, before you do anything, first ARRANGE YOUR CLOTHS/PANS UNDER THE BIKE.!

1. Installing the Bolt to Lock the Engine at TDC:

  1. Remove one Spark Plug. Reasons are to both measure the TDC and if you don't you will get massive compression and won't be able to rotate the crank.

  2. On the LEFT Side of the Engine Underneath the water pump is a Stainless Aluminium Bolt with an Allen Head. It leads into the Crankcase. In order (I'm LAZY) to NOT have to drain the oil first, I lent the bike over to the Right against a wall (While on Centrestand i.e. One leg so tie it back and make sure it is STABLE), and removed the bolt which has a crush washer under it which should be replaced after about 2-3 uses. The leaning will (mostly) prevent oil falling out the hole.

  3. Now what I did the first time is to engage first gear and rotate the Crank using the back wheel. This can be more easily done using a Spanner on the Flywheel nut, by removing the (Higher) Plastic Bung which is on the RHS of the bike, on the Flywheel Cover. No Oil will spill out because this is higher than the oil level. This last method is recommended.

  4. Put a small screwdriver or steel pin into the Spark Plug hole (You will need help here from (Girlfriend / Wife / Son / Mate here) and rotate the Flywheel Nut with your Socket until you feel the piston comes up all the way to the top and I found just a fraction over. If you don’t have the right Socket to fit inside the Flywheel casing, those of you with 97 onwards could also put a spanner on the countershaft nut and do it that way, but do it clockwise.!

  5. Now you will need to take your torch and shine it in the hole where you took the Stainless Allen bolt out of. You should see one of the crank weights with a groove in it. If you're not sure get your helper to rotate the wheel SLOWLY while you look into the hole with a torch and WATCH the Crank go around. The weight will disappear at Bottom DC and reappear, so watch carefully. As it nears TDC go very slowly and you should see the groove.

  6. When you do, and ONLY when you do screw in and tighten up the TDC bolt. This locks the Crank at TDC. You don’t need to over-tighten it as it goes in a slot.

Note: TDC with the Flywheel Cover removed is about a finger or small thumb width between the Ignition Pickup at the top of the engine and the small rectangular steel plate that induces the current for the spark as it passes the pickup. The Rectangular plate is one finger FORWARD of the pickup, i.e. toward the front of the bike.

2. Removing the Flywheel cover (Right side of Engine).

If you didn't drain the oil first, lean the bike well to the LEFT and stabilise as per 2(b) above.

  1. You will need to first Remove the Countershaft (Front) Plastic Sprocket Cover (3 x Allen Bolts)

  2. Then undo all the (about 8-9) Allen Bolts from the flywheel (stator) cover housing. The upper two are attached to a plate covering the wires to the pickup.

  3. Now, there is quite a bit of magnetic pull on the cover, so it won't come off really easily. If you want to save the Gasket (and you can) you will need to be very gentle and ease the cover off evenly all around.

  4. WATCH OUT you do not LOSE the washer which sits on the Gear shaft for the Gear that sits BETWEEN the Starter Gear and the Flywheel Gear. It tends to stick (Due to surface tension in oil) to the inside of the Flywheel cover and then drop onto the floor. There will be some oil spillage.

  5. Open up the cover to the left like a door and take a piece of wire or your zip tie and tie through one of the bolt holes, onto the frame. Your seat should already have been removed.... :-). That will hold it out of your way.

  6. You will see the flywheel, the starter Gear and the Gears in between. If you JUST want to look at the Stator, it is on the cover. No starter and no flywheel removal required!

3. Removing the Flywheel.

  1. Now take your cloth and WIPE all surfaces around the Flywheel nut so you don't asphyxiate yourself, then take the blowtorch, heating tool and heat the Flywheel nut.

  2. ASSUMING you were successful with the TDC bolt, you can now remove the nut retaining the Flywheel. If you haven't yet installed the TDC bolt, and you drained the oil, INSTALL THIS NOW, using a spanner on the Flywheel nut as described above to turn the crank. (Make sure you're in Neutral to do this). Refer the TDC Bolt FAQ. Before removing the 30mm NUT put the bike in gear and hold the rear brake when trying to break it loose.  If you have problems removing the nut, refer Additional Tips on Flywheel Removal below. (Careful use of a propane torch should be ON THE NUT ONLY, NOT THE ROTOR!)

  3. OK, when the nut is removed, screw on the Special BMW Flywheel Puller Tool and screw it over the flywheel, then tighten up the centre bolt until the old Loctite "Cracks". The Heat should have helped you out here, if it doesn’t come apply more heat and use a longer handled Socket Wrench.

  4. Again there is a fair bit of Magnetic pull, but you can now ease off the flywheel to reveal, Lo & behold, Tada, the Pathetic little woodruff key that you've spent all this effort to get to. It should be at or close to the top of the shaft if you got TDC right. This Photo also has all the gears off which you do NOT need to do.

  5. Using a PLASTIC or wooden drive or gentle screwdriver action tap the front and back of the key until it pivots and loosens in its groove, then gently tap it out.

  6. Equally gently tap in the new key with the CUT OUT SLOT facing the REAR of the bike. This will allow the flywheel to rotate a bit more clockwise effectively giving you the timing advance you’re after.


4. Replacing the Flywheel.

  1. This was the Hardest part for me and boy did I struggle the first time. Then my Girlfriend came out and it was on in 30 seconds (The flywheel :-)).

  2. Here's what you do. CLEAN VERY thoroughly the shaft and flywheel (inside). The BMW Manual says use Loctite (the More Permanent Stuff) i.e. BMW or Rotax specifies freakin' Loctite 648, pretty strong stuff, on their flywheel taper. Note that the Clymer Manual says you don't need Loctite on the shaft when reinstalling. Why? Flash says "It is a TAPER. NEVER put ANYTHING on a taper. Clean it and assemble DRY."

  3. Feed the Flywheel gently onto the shaft making sure you line up the groove in the flywheel to the woodruff key. It will NOT go onto the flange on the Flywheel Gear straight away. If it does, Go Buy yourself a lottery ticket and Propose to your Girlfriend, Remarry your wife, whatever. Do not force it and do not at this stage rotate the partially placed flywheel on the shaft as you will damage the woodruff key.

  4. What you need to do is actually rotate the whole flywheel and shaft together. To do this you need to YES, you guessed it, remove the TDC Bolt or at least unscrew it partially. Boy sure looks like removing the oil first is a good idea now doesn't it, leaning the back and forward is a Royal PITA.

  5. OK having released the Crank to rotate freely and assuming your one Spark Plug is still out, engage Gear and get your helper to Rotate the Crank, with the Allen Key. She/he should rotate it Clockwise while you push gently, the flywheel back onto the shaft and over the flange. It only requires a small rotation but it requires rotation. It'll just pop on.

  6. Now when it does before you get all excited and do up the nut, you will have to re-engage the TDC Bolt. So look at Step 2. again.

  7. THEN Rotate the flywheel clockwise on the shaft so that the groove comes up against the cut-out in the new key. h. Put some Loctite on the threads of the shaft and replace the Nut, Torque to Spec.


Alternatively, if it just won't go back on, pull the starter motor back after removing two bolts (marked Green in this photo). (You don't have to pull it out all the way, just slide it back far enough). Then you can spin the big gear behind the flywheel WHILE you push it straight on. No problem. THEN stick the starter back in place.

5. Replacing the Cover.

  1. Wipe all surfaces clean and if you bought a new Gasket smear it with oil first, both surfaces.  Put a small dab of RTV on the rubber where the stator wires pass
    through just to be sure.

  2. Check the washer from 3(d) above is in place, the rubber surround to the ignition pickup wires are in place and gently ease the cover over the flywheel. It will try to pull on strongly due to the magnet. Be GENTLE or you will rip the Gasket.

  3. Do up the Allen bolts going around the cover doing each a bit at a time, then torque. Don't forget to put the top plate back (2 Allen Bolts).

  4. Replace the Sprocket Cover. e. DON'T FORGET to REMOVE THE TDC Bolt and reinstall the Stainless Plug Bolt. Put a new crush washer one, they are pittance cost-wise, but if you can't get one you can use the old one.

  5. Crank her up. It may be leaner so check out this site to make sure your plugs are a good colour and not overheating: http://www.nightrider.com/biketech/spkplghnbook.htm



You can complete the Whole Job (including the Oil Change) in about 2-3 hours and it is recommended you do it to coincide with a regular Oil Change.


OK now you've read all this stuff, TEAM-PAMI in Germany, to whom I have no affiliation did some Dyno runs with the Ron Woods Key and reckon the stock is actually optimum power for this bike. Saying that I felt it DID give me more oomph low down, but it was running so lean when I chopped the plugs I'm sure I could see little bits of Aluminium on the plugs from the head. Not a good sign. I could definitely have richened the mixture a bit as I was lean from my Staintune and Airbox Organ pipe Cut-out, but in the end I did all the above once more and replaced the original key as I thought about Team-Pami’s comments. I think if you did it like Ron Woods did, maybe one of those rather expensive Nikasil Pistons would be in order :-). This would be the LAST mod I would do. Pipe & Rejet nets you more power and an Ohlins shock is a very nice but expensive replacement for the Stock Shock.

Cheers and Regards and a Big Thanks to Richard230, Harl, Fede, Craig, Todd, Flash, Walter and Mark58 the latter who wrote the following oh so true statement:

Other Comments on the Ron Woods Key

1. by email from Team-Pami

2. by Walter #466

I have the Staintune (baffle out), Dynojet kit, and Ron Woods offset Key. I've run close to 10,000 miles with this set up and love it. I'll be putting the full Woods kit in soon. With this set up I can stand the bike straight up in first gear, bring the front end up in second, and reach an honest 105 mph (by GPS) quickly. I did all the work myself and if you are mechanically inclined it's not hard at all. 

The installation of the key is not hard provided that: 

Additional Tips on Flywheel Removal
by Flash, Hombre sin Nombre

See also Clutch Plate Springs FAQ - Removing the NUT holding the Clutch Basket on

Problems removing the 30mm NUT that holds the flywheel on? e.g. So far I'm stuck at getting the alternator flywheel off. I cannot get the 30 mm nut off. I tried putting the bike in gear and holding the rear brake when trying to break it loose, (per the Clymer manual) but no luck. I just keeps moving the flywheel and the crank *counter clockwise* (will this screw anything up?).

Some bolts cannot be undone alone - you may need a strong and beefy assistant to steady the bike and hold the brake, and you'll need a proper breaker bar (extra long socket wrench). If it's assembled with Loctite 243, use of a heat gun (or careful use of a propane torch ON THE NUT, NOT THE ROTOR!) may be necessary. If a previous mechanic mistakenly used Loctite 648 (per OEM) or Red Loctite, serious heat will be REQUIRED, not optional.

Get a 30mm socket for a half inch drive. Get a half inch BREAKER BAR. If necessary, get a piece of iron PIPE that fits over the breaker bar. Put the motor in gear. Put the TDC bolt in. STEP on the brake pedal. PULL ON THE BREAKER BAR WITH THE PIPE ON IT. If you are pulling in the wrong direction, you will be tightening the nut (s).
(Although with the clutch out, having it in gear doesn't do shit.). If you are afraid or just CAN'T get it to budge... tote the bike to any place that has air tools and get them to use your socket on it, with an air wrench. Two seconds later it will be off. (Clutch or alternator, four seconds for both.)

The next level involves use of a large commercial air impact wrench for removal, however, use of heat is still recommended, as if there is Red Loctite in there and it's not softened with heat, you can break things or rip the threads right off the assembly. (Not likely in this case with a hardened crank, but you never know.)

If heat AND an air wrench won't get it... eww.

If you have the proper wrench setup, don't be afraid to get the nut up to 100 degrees centigrade (212F), maybe even 225F. No higher or you start to ruin seals, and the magnets in the flywheel don't like excessive heat either. Best to start off organized, all tools in place, a dry run, quickly apply massive heat on the nut with precision, remove and cool down with a fan. With regards the heat, I'd be a bit concerned about the magnets because there ARE no seals.

The Clymer manual shows a "rotor holding tool" that they use. There are also Motion Pro Clutch Basket vice grip pliers (which seemed to beat up the clutch basket). (Neither worked for this guy, ed).

With regards to having the TDC bolt in place when you undo the Flywheel nut.

You have a gearing disadvantage on the bolt by whatever gear you have it in when you go to loosen the countershaft nut. You have a disadvantage of only the primary drive when you go to loosen the clutch basket nut.

The alternator nut is ON THE CRANK and you are reefing right on the bolt. But... what're you gonna do? You HAVE to hold the crank somehow. Putting the clutch back together is one option. An impact wrench on the rotor nut against the TDC bolt is the only other one I can think of. Or FINALLY (not recommended), I suppose you could drill the nut and break it off with a chisel if all else fails.

Non starting engine after Removal of Flywheel
by Flash #412 & jp7474

The Problem:

I bought a F650 97 for practically nothing, but I had to do an engine rebuild on it. Before doing it, it was starting but running with very high vibration (abnormal even for a 1 cylinder). I did the job, put the engine back in place, but now it's impossible to start it.

When I first tried, I got very big backfire but it was due to a Valve timing issue. I readjusted the timing, and now the backfire issue is gone. The chain tensioner was not doing the job and the drive chain was really slack. After corrected that, the backfiring problem disappear. But still not starting.

So probably it's not a gas problem cause it was backfiring before but Battery, starter motor and electrical components are working fine.

I don't think that I have set the cam lobs in the wrong 50/50 way (If the Clymer manual is right), I looked at that several times.

The work done on the bike:

The engine was removed from the frame and I changed the piston, new ring set. In having the engine apart, I open the engine lower end to investigate if balancer shaft and crankshaft were correctly align and if there was any part to change (for the big vibration problem). I put everything in place correctly and close back the crankcase.

Here's the parts that I removed from the engine and put back in place: Everything that was needed to access and separate the crankcase!!!

As reference, I used the Clymer manual. I know that the problem can be a lot of different things.

The Things to Check and how to check them


If you don't have fuel delivery problems, ASSUMING that you have GOOD SPARK PLUG WIRES and GOOD SPARK PLUGS and GOOD COILS, you have either ignition timing or valve timing problems.



Please explain how you readjusted the Valve timing.


Checking Electrical Problems


Then it's Spark Timing