This is a very interesting thread. I love it.
My 2006 DE300 had the smaller ignition. After I had Ron Black modify my 300's head, tight singletrack rocky off-camber turns instantly became more exciting. Sometimes, my bike's rear end would complete the turn before the front.
I then added a 10 oz fww to the flywheel to regain some control. It was a perfect (for me) solution, and worked like a charm.
I never experimented with a heavier weight on that bike. (and I still cry about it's theft. )
Looking at the photos posted in this thread, I see that this flywheel weight looks much like the "weight" that came in the original '96-'98 GG 250 counterbalanced engines with the extra lighting windings (Ducatti?) bolted to the inside of the magnesium ignition cover (and that GG later used on the 300cc quad).
The "weight" on those ignitions was an "internal rotor" to "excite" the windings.
It weighed very close to 23 oz, and had machinings on the underside of the weight to match the protrusions on the outside of the flywheel. When you tightened the separate fw nut, the mating of the machinings to the protrusions locked it in place, instead of only friction doing the job, as is the case with most of the fww that we see on the market.
When my son, Josh, first removed this weight from his '97 EC250 flywheel, it had a definite effect on his A-level riding style. In the hare scramble that weekend, he was blowing through turns. In fact, he came into the pits wailing about his brakes, saying that they weren't working. I told him that he was going into the woods with both wheels locked up; and his brakes were working fine. He was simply accelerating faster on the straights than he was used to on that bike (which still had the counterbalancer installed, and so was still running a fairly heavy crankshaft assembly).
But, Josh's racing style at the time was very aggressive, and not based on the engine being extremely controllable.
I may pull one of these older '97 flywheel weights out of my parts bins, and put it on my secondary bike, a 2004 XC300, just to see what effect it has on it's power delivery.
Thank you all again, for analyzing your experiments, and sharing your experiences with the rest of us in such a factual and interesting way.
Good Riding!
Jim
