2 more questions:
Before I found this site, I found a strictly Mikuni Carb forum. I asked my same carb recommendation question there and it was suggested that I use:
-#110 main jets
-#17.5 pilot jets
-reclip jet needle to the 4th slot
-air screw out 1 3/8 turns
-pilot mixture screw out 1.5 turns
Is this similar to the recommendation you gave me?? Why this big difference in main jet size recommendation?
Second question: Is there a thread, post or sticky in the forum that explains the 'highest rpm method'???? Thanks!
I guess everyone at the "Mikuni carb" forum likes to run their bikes lean.:roll: As in real lean at the main and jet needle circuits.
Your stock mains are 102.5 Going up to 110's isn't nearly enough. 127.5 or 130 is my guess. Still depends on that home made pipe of yours. To back me up on the main jet choice, consider this: Dynojet supplies a 138 main jet in their stage 3 kit. DJ and Mikuni use different methods to come up with their main size (Mikuni = cc's that flow through in a minute and DJ = the actual size of the hole in mm's). A 138 DJ is nearly identical to a Mikuni 130. Check the web for a comparison chart if you wish.
I have no argument over their pilot jet choice. I see no reason NOT to give the stock 15 jet a try if you richen the pilot fuel screws. If it doesn't work, get the 17.5's. Many times the 15 does work. Also, DJ suggests keeping the pilot circuit stock when using their kits. Why buy jets if you don't need them?
As for their jet needle position choice, your stock position is #3. Any decent pipe/pod mod will require you to richen the needle more than 1 position. Try the bottom. As I said earlier, the stock needle, even at the bottom (2 positions richer) may still not work and you'll need a DJ kit.
As for their air screws setting, there IS no "setting". Each bike can be a little different. You set them using the highest rpm method. They may end up 1 1/2 turns out, or maybe 2 turns out or somewhere in between.
A search would show you but here it is: set the screws to 1 1/2, adjust throttle cables correctly, warm up the bike completely and place on centerstand, set idle to 1,000 rpm's with the idle adjuster knob.
Starting at any carb, slowly turn a screw in either direction until you hear the rpm's max. Fine tune it. Now lower the rpm's to 1,000 by adjusting the idle adjuster knob. Repeat this to all other carbs.
As for their pilot fuel screw setting choice, I said 1 1/2 was a good starting point. If the pilot circuit isn't the correct mixture by the time you have these 2 1/2 turns out, go to the 17.5 and reset the screws to 1 turn out and test.
I'm not sure why you're asking me if their set up is similar to my suggestions. You can see for yourself. I typed a long and detailed message trying to help you and to avoid confusion. Maybe my messages are too long and people skip over some of it?
If you want to trust this Mikuni forum over my suggestions, that's fine. I know what works. I've jetted many bikes over the internet and most of them at this site. Many members post back to say the bike runs great and on the first try. We all know getting the jetting right on the first try is very hard to do or just plain lucky. I keep notes about previous jetting set ups and that helps. I admit that your home made pipe may add a twist to your jetting and it may not. I don't have much jetting experience with home made pipes. Mostly V&H, Yosh, Kerker, Jardine, Mac...
