http://www.bmeengine.com/
The BME site is up again. Dial it in and look in the manual section.
Take a few minutes to sort through to the info that's important to you and see if it makes a difference. This other blurb is from an old RCO thread from October of last year. Don't know if it will help, but it can't hurt.

I'm a new big engine user and have a 3W-100B2 in an Edge 540. I have about 30 flights on the plane/engine and suddently on my last flight the engine quit. I was at low power and went to higher power and the engine didn't even sputter, just stopped. I ran approx. 5 gal. on normal oil and switched to Honda HP-2 (50:1) 5 flights ago. I adjusted the carb and it seamed fine.

I'd like some hints on that one also!! Last year I had the exact same thing on my G62 - just quit like it was electric! This was right after take off and I didn't make it back to the field. Ouch! I too had only around 35 flights on the engine. It had been sitting for a couple of years (only 6 flights before that). Ran fine after that, but then it also ran fine from flights 6 to 35???? No problem with my Q42 0r Q52!

I have a 3W-150SS and may be able to offer some suggestions. When you switched from break-in oil to synthetic, your engine could be running hotter. This causes "stale" air around the carb in a situation like yours. The answer is to open a hole in the cowl right below the carb - this clears out the stale air and gets freahs air to the carb. Also, check your duct workt o make sure the engine is cooling properly. If you have a temp gun - that is even better.

If you had gas to the carb, it is probably isolated in the carb. These Walbros will idle with a high-speed jet clogged; but they won't advance through high speed. A good cleaning and a carb rebuild kit (about $13) would be a good investment.

The 100 has a Tillotson carb, check the screen behind the rear plate for debris-you really need a good filter on these things. Most 3-W motors go rich and load up after awhile, the same thing happened to mine. Start turning the High speed needle in a 1/16 at a time, but don't go below 3/4. Also look at the plugs, they should be a light tan color. They are pretty tempermental until the rings get fully seated, takes at least 10 hours!!!!

The problem most likely lies with the seal between the pheonalic plate and the reed assembly. you will need to get some Loctite 515 from a small engine repair shop(the only place I have been able to find it) and use a thin coat on both sides of the rubber gasket but do not get it in the small ports that are on one side of the gasket and plate. What happens is the spacer can warp after some usage and the resulting air leak causes a lean condition. I hope this helps!! email me if needed. I believe C. Lee addressed this issue some time back.