Another carby questions

[albi]

Hello my fellow GSers.

I've scoured the archieve using the search function, however, more than likely due to my idiocy, haven't turned up an answer to my question.

I'm running a 4 into 1 pipe and authentic K&N pod filters. As you'd expect, the bike is running a little lean, so, not being able to afford a Dynajet kit, am looking for other options.

Currently the jets are 115, and the needles are set at stock standard, second from the top notch.

Bearing in mind that there are 5 notches, where would be the best spot to set it? Also, what size jet would suit?

I appreciate any comments and suggestions.

Thanks, Alex

[KEITH KRAUSE]

Using the stock jet needles, one to two positions richer would probably work. If you have access to jetting spacers, I'd probably try 1 1/2 positions richer to start. A jetting spacer is used for "1/2" position changes. They are approx' .022" thick. If your factory needle e-clip position is the 2nd groove from the top, then place the e-clip in the 4th groove from the top and place the jetting spacer directly on top the e-clip. This would be position 3 1/2. Any factory spacers must be re-installed in correct order. Test at 1/3 to 1/2 throttle position and get plug reads. Do what the plugs/performance tell you.
For the pilot circuit, you can TRY adjusting the mixture screws richer to see if adequate mixing is within their range. If the pilot circuit is still lean after you've adjusted the mixture screws out to approx' 3 1/2 to 4 turns, then you're out of their effective range and you need to go up a step (2.5) on the pilot jets and return the screws to factory position. Test at minimal throttle positions to see how the pilot circuit is mixing. Read the plugs.
As for the main jets, instead of me guessing, look up Dynojet if you can and see what main size comes in their stage 3 kit for your model. You can also ask someone here with your model. If you can't buy separate DJ mains, then check out a jet chart that compares DJ jets to Mikuni jets, and buy the matching Mikuni jet size. For example, a DJ 138 main is the same as a 130 Mikuni jet. The numbers are different only because the number reflects the manufacturers method of sizing. One rates their jet size by the cc's that pass through in one minute and the other simply goes by hole diameter. Test the mains at full throttle. Chop off and read plugs.
I can't remember where I found the jet chart but it shouldn't be too difficult to get the correct size main from a member here if you can't find the chart.
Remember, you must also bench synch the carbs and then synch with a vacuum tool to do accurate testing.
Also, the CV's can be difficult to adjust. You may find you have to drill out the vacuum orifice to the piston/spring assembly (slide) in each carb. This may be necessary if you experience poor throttle response. I don't know the size of the increase. A drill bit is included in the DJ kit I believe. You may have to install the air jet restrictors that are in many kits. Again, the CV's can me more difficult to tune than other carbs. Sometimes it's more involved than just simple main/jet needle/pilot jet changes.

[albi]

Thanks Keith, that's very helpful.

[feelergaugephil]

Kieths a whiz with carbs! he helped me a few years back with mine (on the site) and never had an issue with them after that.