OK. Ready for more Tuning Help.

[Rocketjock]

As I'm waiting for spring I've given it a rest but here's an update. My 06 B12 now has a 2Bros can installed with Ivan's stage 1 carb kit. Way loud but I'm gonna live with that for now. Read that one interesting post about actually packing the can with furnace insulation or such like but for now it's earplugs only. With the stage 1 kit I drilled out the pilot screw plugs to find them factory set at 3.5 turns. Adjusted to 4 turns as prescribed by Ivan (starting point) and went for a buzz. Screaming mid to topend range power. Real happy with this but I still had a bit of low end stumble. Made the mistake of turning down the screws to 3.5 and got definate bad running at low to mid with a big increase in decel pop. Put it back to 4 turns and same as before. Is 4.25 or 4.5 gonna give me what I want? Which is, of course, smooth running in all ranges. Oh ya, I have to mention that I did a carb sync with an inexpensive set of dial gauges that I bought for just under 100 bucks. I was able to sync all carbs equally as per instructions but I do question how good the gauges are. Of course if I spend the money at the shop to get it done I don't really know if they can do it any better.
My insurance this year is almost 900 bucks for 6 months so I am still planning my 6 month stint. And that with the 4 year safe driver discount. Pirates!  

Addendum: Rereading this I'd have to say that it wasn't really low end stumble (only before it was warmed up) it's more like low to mid range slight missing when cruising.

[2005B12S]

I had my Ivan's kit on my '05 for a few months. Had the mixture screws at 4+ out. Never was satisfied with the low to mid performance. It was still too cold blooded, it ran better at 80+F, when colder it still had a lean off idle sputter.

I think a better solution is to up the pilots and run the screws in the 3.0 out range. There is a conversion chart for Mikuni that will equate the difference in screw settings for a given pilot size.

The problem is if you go much more than 4.0 turns out, you start to run out of adjustment, not to mention risk loosing the screws. I would have went the pilot change route if I had kept the Ivan's kit.

Good Luck, Ed.

[Rocketjock]

So, what you are talking is a larger pilot jet size? And are you saying you replaced the Ivan's kit with something else?

[2005B12S]

Yes, larger pilots. Search the forum and you will get some hits - others have gone to larger pilots.

I did replace the stage 1 kit, but with RS36 carbs. If I was gonna stick with the stock CV carbs, I would get rid of the airbox and go with the HS kit and pods.

I think a large part of the 2G problem is the airbox. The 2G frame design dictated an airbox redesign, IMO it is too small and restrictive.

Good Luck, Ed.

[Rocketjock]

I have done the 20 drilled hole setup as prescribed by Ivan.

[CWO4GUNNER]

Did that include the main jet increase change to 125? I used a morgan CarbTune $125, no gauges only stainless metal pegs in glass tubes working off vacuum pressure to lift them off for true vacuum sync. All other calibration devices I have used are awful in comparison. If you are using cheap analog gauges you should first calibrate each gauge separate against carb #1 @ 1500 RPMs adjusting each gauge if possible or noting the difference in each gauge reading before conducting the sync. Make sure you use a box fan to keep the engine temperature stable otherwise the calibration and sync will be erratic. Incidentally I set my pilot jets to 3.75 turns wanting to be in the middle of Ivans recommended 3.5-4 turns and amazingly with an accurate sync It worked perfect. The only time I get any mid hesitation is when it is cold but I always let my bike warm up so I never notice it.

I have done the 20 drilled hole setup as prescribed by Ivan.

[Rocketjock]

Thanks for that, CWO. Yep, Ivans' came with the 125 mains. That's a good tip on the calibration process. I only aligned the needles in the gauges. I will do it again using #1 carb. I can't see setting my pilots to 3.75 as it ran better but not best at 4. And like poo at 3.5. It was definately cold when I tested, tho. Way colder than summer. I just figured that when warmed up with all that engine heat heading back and across the carbs, everything would be toasty. Guess it doesn't account for the icy air entering the box.

[CWO4GUNNER]

If you have trouble calibrating each gauge separate, go the the pet or aquarium store and buy a cheap 4-way air manifold they use for distributing air to different parts of the aquarium ($5). Use the manifold to attach all 4 gauges to the one carb that has easy access to the gas tank vacuum hose (carb#1?). Now you will see the true deviation between all 4 gauge at the same time using one carb. Then moving the gauge needles until testing each time until they are all perfectly pointing in unison revving the engine between 1.2&1.5K to verify. Then you will be ready to use them separately and accurately which is critical for a good sync. Whatever you set your pilot jets to, when spring arrives take your bike for a 3-4 mile ride at 1/8 throttle maximum (pilot jet circuit). When you return try and shut the bike down without idling it and pull all your spark plugs to see if the pilot circuit is burning brown (good), and not ash white (lean) or sooty black (rich).

Thanks for that, CWO. Yep, Ivans' came with the 125 mains. That's a good tip on the calibration process. I only aligned the needles in the gauges. I will do it again using #1 carb. I can't see setting my pilots to 3.75 as it ran better but not best at 4. And like poo at 3.5. It was definately cold when I tested, tho. Way colder than summer. I just figured that when warmed up with all that engine heat heading back and across the carbs, everything would be toasty. Guess it doesn't account for the icy air entering the box.