Author Topic: Help! Need ballpark jetting suggestion for 1G 1200 (Read 3130 times)

ArcticEd · « **on:** April 26, 2006, 06:54:48 PM »

My son has a 1200 that we got off of Ebay, a rebuilt crash victim. The seller said that the bike (pre-crash) had a slip on and pod filters, but in the rebuilding, he stuck a stock can and airbox on it (parts laying around). We know that there has been jetting done to it, (Somebody's kit cause the floatbowl screws are allen heads and the plugs over the mixture screws are drilled out) He's got a K&N in the airbox with a 2 inch hole drilled in the cover and a Supertrapp bolt on on it now and the bike runs gag rich.... We had to replace the o-rings where the float valves press into the carb bodies and are waiting on new ones for the plastic enrichener tubes. The mains currently in the bike are 160s ( The microfiche at the local dealer says that the stockers are 102.5s !?!?).
He can't afford another jet kit right now, and I don't wanna screw with it forever trying to get it right, so if anyone can give us some ballpark specs to get started with, it would be greatly appreciated.

theroamr · « **Reply #1 on:** April 26, 2006, 07:43:00 PM »

With a slip on and a k&n with 2" mod hole,,,,,I would go with fuel air screws about 2 3/4-3 turns out. The pilots leave alone. The needles if they are after market go with the second or third notch. If they are stock needles try 1 or 2 twenty thousandths shims. The mains you need to be between 117"s and 127"s.

My bike has a scorpion slip on with k&n with 2" hole mod and this is what I run. I went 122.5 on the mains and the second clip on the needles. Fuel scews are 3 turns out.

Hope this helps, this is where my technical knowledge about ends.

ArcticEd · « **Reply #2 on:** April 26, 2006, 08:37:49 PM »

(In my best "Elvis" voice....) "Than' you, Than' you verrah Much.."

theroamr · « **Reply #3 on:** April 26, 2006, 11:35:48 PM »

Welcome.....

Red01 · « **Reply #4 on:** April 27, 2006, 12:25:05 PM »

Taking a guess here - but with numbers that big, I'm guessing the kit is a Dynojet - they use their own jets and numbering system, as opposed to everyone else who use OEM vendor jets.

theroamr · « **Reply #5 on:** April 27, 2006, 09:18:52 PM »

I think dales jet kit with pod filters on the 1st gen bandits ran 150-155's. So I think its normal for them to have been that large with the pods. I do agree the dyno jet kits were way differ in their sizing.

99er · « **Reply #6 on:** April 28, 2006, 07:31:15 AM »

Red01 is probably right. I never heard of a 160 but 150-155 standard Mikuni are the go for pods. The Gen I DynoJet kit was total crap and caused many early listers headaches. I recall they replaced the emulsion tubes and the threads are different. Your saving grace is that you have a 2" hole and that was not a DynoJet mod. You CAN buy a set of 4 Mikuni mains - $10 to see on the cheap. in the end, you can't be sure whatexactly was done prior to your ownership.
I run a K&N with a Dale pipe and the 2" mod down here in Atlanta so we're similar. I could not get it to run right on stock needles but Gen Is are finicky and differ from bike to bike. Considering PA's climate, I'd try a 132.5 main. I'm running a 135. That should get you good full throttle. Adjust the floats to about 14mm. Raise the needles until the hesitation on part throttle cruise around 4-5KRPM goes away. You can add 35 pilots to crispen the response if you wish and you're done.
The K&N flows real well. When I added it with the 127.5 mains standard for the 2" mod, it ran like crap - 7K shutdown at full throttle. I had to "tape-off" half the filter. Note that a 2.5 jump in main is significant.
Good luck!
Marc/Atlanta