crazycanuck Posted July 14, 2011 Report Share Posted July 14, 2011 Hey guys sorry if this is in the wrong spot, but i need some help. I am working on my buddies 07 yfz 450 and am installing the following -sparks racing full system -fuel customs intake and filter i got a new needle and a bunch of jets. i was just wondering what a good starting point is for jetting?? im @ 2300ft OH and where the F$#K is the the air adjust screw??????? Quote Link to comment Share on other sites More sharing options...
bigborebanshee Posted July 14, 2011 Report Share Posted July 14, 2011 Good luck with that fuel customs intake kit,they definitely flow better,but you have to make sure the velocity ring is pinned to the carb in the correct position.You can use 2 clamps.one for the flange and one to hold the ring in place.If not,the ring can become dislodged or spin covering the air bleed holes. Do a search on them if you are not familiar with them.The last one I installed went from 53 hp to 58 on a built 450. Quote Link to comment Share on other sites More sharing options...
crazycanuck Posted July 15, 2011 Author Report Share Posted July 15, 2011 Good luck with that fuel customs intake kit,they definitely flow better,but you have to make sure the velocity ring is pinned to the carb in the correct position.You can use 2 clamps.one for the flange and one to hold the ring in place.If not,the ring can become dislodged or spin covering the air bleed holes. Do a search on them if you are not familiar with them.The last one I installed went from 53 hp to 58 on a built 450. Did you keep the air box?, would u happen to have any pictures of yuour setup? Quote Link to comment Share on other sites More sharing options...
bigborebanshee Posted July 15, 2011 Report Share Posted July 15, 2011 Did you keep the air box?, would u happen to have any pictures of yuour setup? i don't have any pics,but you will have to chop your air box up a bit.You want to leave most of the factory mounting brackets in tact and cut away what is necessary to allow the intake to line up with the airbox hole..The factory airbox will still act like a support and work as a water/mud deflector. heres a diagram.You will need 3 worm clamps Make sure the ring is properly positioned and FLUSH with the carb bell.Clamp the carb boot at the bell first,then double check the ring and clamp the boot right around the ring itself.this will keep the venturi ring in the proper position.as long as you leave those 2 clamps alone,you don't have to worry about the ring moving Quote Link to comment Share on other sites More sharing options...
crazycanuck Posted July 15, 2011 Author Report Share Posted July 15, 2011 lol... im not familiar with the newe yfz's but this is what i THINK first of which needle did you buy? start off with a 165-175 main 45-48 pilot needle in middle clip that should start you off a bit rich... the air screw is under the carb If I remember right its a red screw looks like this http://cgi.ebay.com/ebaymotors/MSR-AIR-FUEL-MIXTURE-SCREW-FCR-Carbs-Yamaha-YFZ450-/290489898749?pt=Motors_ATV_Parts_Accessories&hash=item43a28c16fd#ht_500wt_1182 also i'd advise to also buy a quickshot for the carbs... those carbs get a pretty bad bog downlow and the quickshot will cure that. You can buy a quick shot cover that has the adjustable air screw so its easier what is this quickshot u speak of?? Quote Link to comment Share on other sites More sharing options...
bansheeboy44 Posted July 16, 2011 Report Share Posted July 16, 2011 Hey guys sorry if this is in the wrong spot, but i need some help. I am working on my buddies 07 yfz 450 and am installing the following -sparks racing full system -fuel customs intake and filter i got a new needle and a bunch of jets. i was just wondering what a good starting point is for jetting?? im @ 2300ft OH and where the F$#K is the the air adjust screw??????? I believe Spark's website has jetting suggestions, but the other suggestions were right on. Start w/ the 175 main though. Quote Link to comment Share on other sites More sharing options...
sleeper06 Posted July 16, 2011 Report Share Posted July 16, 2011 45 pilot 175 main ncvq dirt bike needle 4th clip,do not spray any cleaner on the slide ,the o-ring will expand not seat rite and run like shit,is the cam mod done? Quote Link to comment Share on other sites More sharing options...
camatv Posted July 16, 2011 Report Share Posted July 16, 2011 adjustable leak jet quick shot is awesome.. last one i did like that i ended up with a 50 pilot and 170 main with th e OEM needle the 07 i believe has an adjustable needle. the quickshot and adjustable idle air screw is nearly mandatory after any pipe install the bog is GONE and that makes a world of difference. gave the bike back to the dude and he nearly flipped it first time out. i think the quickshot is what made it possible to keep the oem needle. this one was an 06 if i rember or 07? Quote Link to comment Share on other sites More sharing options...
crazycanuck Posted July 17, 2011 Author Report Share Posted July 17, 2011 OK so... I sweated my balls off all day workin on this POS and this is what I ended up with 172 main 48 pilot dirk bike needle, middle clip. 2 turns out I fuckin hate 4 strokes so i donno, it sounds like a LOUD wet fart and pulls hard. The Fuel customs intake was a pain in the anus lol...... but turned out ok. I ended up not using the air box as we usualy ride in the same conditions. I did notice the low end bog right from idle, Is this the problem that the quick shot solves ?? AND i took it for a few good rides and the fan never once kicked in.... WOW WAS MY LEG HOT IN SHORTS Quote Link to comment Share on other sites More sharing options...
crazycanuck Posted July 17, 2011 Author Report Share Posted July 17, 2011 45 pilot 175 main ncvq dirt bike needle 4th clip,do not spray any cleaner on the slide ,the o-ring will expand not seat rite and run like shit,is the cam mod done? what cam mod does everyone do ? i think ive read it before tho.... advances the timing?? lol i donno Quote Link to comment Share on other sites More sharing options...
coryv4 Posted July 18, 2011 Report Share Posted July 18, 2011 what cam mod does everyone do ? i think ive read it before tho.... advances the timing?? lol i donno i believe the you advance the exhaust cam 1 tooth and leave the intake and i guess you will notice a litttle more bottom end my cuzin has this mod done and it has alot of bottom end but his is the only yfz ive ever ridden Quote Link to comment Share on other sites More sharing options...
camatv Posted July 18, 2011 Report Share Posted July 18, 2011 450 has timing markings from a wr450 the cam mod moves the cams to the yz450f timing it makes a tad bit more top end. not much but a lil. the quickshot will cure the bog 99% if you attach the pumper jet to the actuator it will also help a lot. i also donot like the fart can bikes either.. ( this in the yfz world is called the o-ring mod) i am so tired of hearing changes stated as MOD's only see it in the 4 pokes. 2 mod 3 mod 4 mod bullshit Quote Link to comment Share on other sites More sharing options...
sleeper06 Posted July 20, 2011 Report Share Posted July 20, 2011 In the yfz world they also do a zip tie mod where they take a zip tie and put it on the throttle cable to clear a bog and call it a mod,i have also seen accellerator pump arms wire tied foe quicker responce to clear bogs,all of these hair brain mods came off as soon as they got in my garage ,nothing you cant fix with jetting and a good ear Quote Link to comment Share on other sites More sharing options...
crazycanuck Posted July 20, 2011 Author Report Share Posted July 20, 2011 In the yfz world they also do a zip tie mod where they take a zip tie and put it on the throttle cable to clear a bog and call it a mod,i have also seen accellerator pump arms wire tied foe quicker responce to clear bogs,all of these hair brain mods came off as soon as they got in my garage ,nothing you cant fix with jetting and a good ear you were the closest sleeper, went to a 175 main 45 pilot, 2 turns out needle 4th clip. Buddy was sooo happy with how it turned out. He said it was a little too loud but i told him to shove it lol . ya i read about that zip-tie mod and there was no way i was lettin it leave the garage with that Quote Link to comment Share on other sites More sharing options...
bansheeyfz450 Posted July 22, 2011 Report Share Posted July 22, 2011 I have a yfz450 dyno tuned @ 6000ft. I am running a 158 main, 45 pilot, NCVQ needle down 2, full Alba exuast, velocity air filter (no lid), and Cam Mod (2hp gain). IMP 175 is way too rich. I would try a 168. Also they put in a #35 leak jet. Quote Link to comment Share on other sites More sharing options...
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