Best jetting for my scenario.
Posted June 27, 2006 - 09:49 PM
I have the carb off and am debating between jets. I'd like to get your advice on the best setup for me. Keep in mind that I'd like to get one "best all around" setup if that's possible even though my riding locations will change quite a bit. I'm ok with giving up a little bit of peak performance but I want to be sure that I don't damage the engine by getting into a too lean situation.
I currently live at 5000' with temps ranging from 50-90. I will be moving to Mexico later this year and will be living 8 months on the beach (sea level) in 80-90 degrees with humidity. The other 4 months I will be in Mammoth and Lake Tahoe California at around 5000-8000' and a dry 70-90 degrees.
I have the JD red needle at the 5th clip position and it recommends a 168 main up to 6000 and a 165 from 6000-9000. I didn't see anything about the pilot jet. Indy's recommended settings say 165 main and 48 pilot for my Mazatlan 8 month portion of the year and a 165 main and 45 pilot for my elevation portion. I'm confused why JD and Indy recommend different Mains. What are your thoughts? Should I stick with the stock 165/45 setup? 165/48? 168/48?
Also, did you guys do anything to the accelerator pump timing adjustment screw of just leave it be? I haven't heard many people mention it but JD recommends it.
Posted June 27, 2006 - 10:20 PM
I am using 168 main, 48 pilot, JD red#4 (or #5 depending on if temp and humidity drops).
If you are having serious issues with bog, adjust the AP squirt. If not, don't touch it.
With your jetting, there is really only one way to find out, that is trial and error. If only we had EFI.......
Posted June 27, 2006 - 10:47 PM
I had a pain getting the carb out enough to access it so I'm hoping I won't have to do this too many times.
Posted June 27, 2006 - 11:25 PM
If rich, it will stumble, sputter if real bad, but run cooler. It is hard to tell if slightly rich unless you change to a leaner setting and you get an improvement.
Now perfect, it will just explode in power, no hesitations, no fuss. You will know if you got it right. This is why it is good to have a play around with a few jet sizes. The needle will have the biggest effect on how your bike runs.
The pilot circuit corresponds to 0 - 1/4 throttle, needle 1/4 - 3/4, main 3/4 to full open. Ues these throttle settings as a guide to find out what you need to change.
Only change one thing at a time as each circuit is effected by them all.
With your jetting, I would leave the needle where it is when you go to Mexico, the pilot and main jets are very easy to change out when you get there. Just go with the 48pilot and 168 main. You might find the 165 is good enough for you depending on how modded your bike is. If you don't have an adjustable fuel screw, get one. They make pilot circuit tuning simple, and perfect pilot circuit will crispen up throttle response.
Posted June 28, 2006 - 07:07 AM
Posted June 28, 2006 - 07:10 AM
Posted June 28, 2006 - 02:16 PM
Any other suggestions before I throw it back together. I'm really debating between what JD recommends and Indy and still wondering how the zipty works.
Posted June 28, 2006 - 03:08 PM
Fuel mixture screw is for tuning the pilot circuit, how ever, it effects the needle and main circuits.
I installed the adjustable fuel mixture screw last night. Does it more effect the pilot jetting portion (0-1/4 throttle), needle or main (3/4-full)? I know I'm going to have to play around with it but the more I know before I do it the better.
Posted June 28, 2006 - 03:15 PM
it makes a little bit of a difference, but any more than 3, 3 1/2 turns out, it doesn't do much at all. If your pilot is too small, turning the FMS all the way out won't make it flow any more. The range is like 1 turn to 3 turns out.
Also, how much difference does the zipty FMS make from fully closed to fully open? This goes with what I asked in the previous post so depending upon which portion of the jetting it effects the most.....is it like having the zipty all the way in is like running a 45 while running it 3+ turns out is like going to the next size jet like a 48? These are just examples but I think you know what I'm trying to ask.
Posted June 28, 2006 - 03:21 PM
Posted June 28, 2006 - 03:35 PM
Posted October 02, 2006 - 09:17 PM
I left Prescott (5200') and am currently staying at my parents in Phoenix (1200' I think) for a few weeks before we move to Mexico the 25th of October. I don't care so much about dialing it in perfectly here since I'll only be here a few weeks but I thought it would be a good learning experience to figure out how the elevation changed my ideal setup. I have been running the stock 165 main, 45 pilot setup with the Zipty at 2 turns out and the bike ran great at 5200'. I went for my first ride at this elevation today and noticed 2 things......it sometimes bogs when I snap the throttle (maybe 10% of the time) and I get popping when I go from full throttle to closed throttle which I may have gotten sometimes before but not as often.
Is there enough adjustment in the FM screw going from 2 to 3 turns to make a big difference or is it definitely time to go to a 48 pilot (which I am awaiting)? I asked this earlier but didn't get a definitive response. Is the difference of the FMS from closed to say 3 turns out equivalent to the next sized pilot or is it less or more? Or for my scenario, will going from 2 to 3 turns be like going from a 45 to 48 pilot? I will go out to 3 turns tomorrow but I just thought I'd ask here so I'm a little more informed.
Also, how does humidity effect things since Mazatlan is quite humid? Is it the same as heat? Am I reading Indy's chart right that the hotter it is the richer the bike runs and therefore the smaller the jets you use?
Posted October 02, 2006 - 09:37 PM
Posted October 02, 2006 - 11:13 PM