XXNUTZ Posted July 31, 2013 Share Posted July 31, 2013 Question for the carbie guru's. I just recently moved to Rio Rancho NM, about 5500 ft in elevation from Chicago, about 900 ft in elevation. Current jetting I believe is a FP Stage one kit. 145's on 1 and 4 and 148's on 2 and 3. Pilot jets are at 3 turns out and .001 shims on the needles. I have Two Bros slip ons and recently put a K&N air filter to give it more air. It is definately rich, especially at idle. Moving, it seems that it could use more punch. I've been emailing Dynojet for advice and they tell me I should put 136's and 138's respectively. No mention of the pilots. Does this sound right? I don't want to go too lean knowing that stock jets are 140's/142's, pilots at 2 3/4 turns out and I have slip ons with a K&N. I was thinking, 138's/140's and put the pilots at 2 turns out (per the manual for altitude) since the cans and filter can make it leaner too. Thoughts? Quote Link to comment Share on other sites More sharing options...
brianmacza Posted July 31, 2013 Share Posted July 31, 2013 Ummm.... I never gave this much thought. My '97 runs at 5700ft and is still on stock jets (DNA filter and aftermarket slipons) and feels stronger than my sons 2000 model XX altho' he has a dirty airfilter that needs replacing - the fact that I have a 16 tooth front sprocket maaaay be a factor here. Does your XX feel more sluggish? Has your fuel consumption suffered?? At your altitude you have about 16% less oxygen than at mean sea level so that would explain some of it. Quote Link to comment Share on other sites More sharing options...
XXNUTZ Posted July 31, 2013 Author Share Posted July 31, 2013 Yeah it feels sluggish down low compared to back in Chi town. It smells rich at idle, Pipes sound deeper and tips are black too. I noticed when I try to start it cold, I barely need to choke it. I think that 16t sprocket you got makes up for it a bit. I rode it today in dry 90 deg air and it just didn't kick like it should. I wanna do this adjustment once and be done if you know what I mean. Quote Link to comment Share on other sites More sharing options...
EVLXX Posted July 31, 2013 Share Posted July 31, 2013 General rule of thumb is 1 size smaller jet for each 2,000 feet in altitude gain, skipping the first 2K. For ALL practical purposes the Pilot Jet "IS" the most important jet... not the main. The pilot Jet "sets the stage" for everything else..... .... So I would, if it was me, start by dropping the pilot 2 jet sizes, drop needle 2, and the Main 1, and your mixture screws will probably need to go in 1/2 turn. Test ride... adjust. Quote Link to comment Share on other sites More sharing options...
slowrideCX Posted July 31, 2013 Share Posted July 31, 2013 My 97 is in the same boat so to say. Not quite as drastic though. I bought the bike with a FP jet kit set up for 800ft above sea level and I live on the east coast about 40' above SL so I really should reset the needles at the very least. The bike just seems to run too good to mess with though. On my last trip home from PA with Erica and a full top box I averaged 44.5 mpg till I got into Jersey. On a day to day I average about 35-37 tops and that is babying the crap out of it. Maybe this winter I will try to drop the needles a bit. I hardly need to choke it when I start it in the morning so I know it is running rich not by much but just enough. Quote Link to comment Share on other sites More sharing options...
XXNUTZ Posted August 3, 2013 Author Share Posted August 3, 2013 Well I pulled the carbs today and found the mixture screws were at 3 turns out except #4 was at 2 1/2 turns...put them at 2 turns and she didn't like that so gave them another 1/4 turn and she like that, epecially with the airbox back on...nice and crisp all the way through...and I don't think my neighbor did any jet changes as the float bowl screws didn't have any markings on them...so I'm thinking the stock jets are still in there...gonna run her tomorrow since it started raining when I got her back together...will report after the ride...thanks all for the advice...cheers. Quote Link to comment Share on other sites More sharing options...
EVLXX Posted August 3, 2013 Share Posted August 3, 2013 Hmmmm... sounds like maybe you are not as far off as you thought. Here is some things to remember... Generally speaking... 0-1/4 throttle is Pilot Jet and Idle mixture screw. 1/4-3/4 throttle is pilot jet and Needle 3/4-Full throttle is Miann Jet. Like I said, Ive never had a sey of Bird Carbs apart, but Almost ALL Carburators have this as a basis... then they add Power Jets, Squirters, MidJets, etc. to fix this or that flow problem.... yada yada.. So.... Even though you may be able to Adjust out the "Starting and Idling" problems with your Idle Mixture screws. You may still want to drop One jet size on the PIlot... and then See how she runs. PS. How dirty were the Carbs? Did you take them out and clean them? Quote Link to comment Share on other sites More sharing options...
XXNUTZ Posted August 4, 2013 Author Share Posted August 4, 2013 EVL, I didn't pull them apart, just pulled them off the rubbers so I could get to the mixture screws...the t-stat housing is in the way of #3...it ran very well today...pulled all the way through...had plenty of twisties and mach speeds with another 'bird...some fine tuning might be in order still but that will come in time...thanx for all the advice...cheers. Quote Link to comment Share on other sites More sharing options...
Desert Goat Herder Posted August 11, 2013 Share Posted August 11, 2013 Remember, Dyno jet main jets don't = Kehin jets. DJ jets flow different so you can't go by what their recomendation is unless you have DJ mains. FP or Factory Pro I believe uses stock type jets so I would contact FP for their setting recomendation. Quote Link to comment Share on other sites More sharing options...
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