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Found 196 results

  1. working on a 2004 yz125, doing the jetting and i had to drop it down from a 420 main to a 400 bike wouldn't even run under load with the 420. so the 400 got it good but i got a bog still at 1/3 throttle so i raised the needle clip from slot 3 (center) to slot 2 and it helped a good bit, i think dropping it 1 more slot would work perfect but is that an acceptable procedure to max out the needle? is it like the pilot jet where if its not between 2-3 turns you have to change the size of the pilot? in my case dropping the main jet size 1 more size or am i okay to max out the needle?
  2. D.Barrett

    jetting '01 CR250 PWK Jetting

    I've been doing quite a bit of reading on the subject but just looking for more insight on my particular setup: I have an 01 CR250 with a 38mm Air Striker from JD Jetting. It currently has the factory(JD) jetting in it: #7 slide, 45 pilot, 175 main, blue needle on #3, air screw 1.5-2 turns out. The bike has a fresh top end(did it when I installed the carb), Boyesen carbon fiber reeds, FMF Gnarly pipe, and a fresh-packed FMF Shorty silencer. The idle/pilot seems to be pretty close, although it may be a bit rich. I've noticed the air screw doesn't seem to have much affect when adjusting it. The other issue I've noticed is a slight bog when I get on it at lower speeds/RPMs. IE: Making a slow, tight turn in first gear and then getting on the throttle coming out of the turn. There's no sputtering/etc, just a bog/hesitation. I'm assuming the needle will play a big part in fixing this, but does this indicate a rich or lean condition? Also, I'm setting this bike up for single-track/enduro/woods riding. Any advice on jetting/needle combos that'll give me the cleaner part-throttle/low RPM response I'm looking for? Edit: My altitude is around 600-700 above sea level(Chicagoland) and the current temps are in the 60s-70s.
  3. JohnClaude

    2005 WR450F Needle Suggestion

    Hi Everyone, I just picked up a 2005 WR450F. I was wondering if anyone had a recommendation for an adjustable needle (it appears that the stock needle isn't adjustable?). I live in Denver and ride from 5,000+, bike also has a FMF Q4 exhaust and megabomb header. Looking for a stock needle that's reasonable and readily available (not JD at this time). Also, fun fact- noticed that the previous owner had stripped out all the philips heads that attach the float bowl to the carb body. Had to access the jets via the hex opening, and the carb is pretty varnished. Should I attempt to cut into the philips head to get a flat head in there to remove the screws? Any suggestions? Leaning towards cleaning things out the best I can without removing the float bowl.....Thanks for the help! -John
  4. Lamborghini Live

    Main jet

    Need some pro tips on a main jet question for my 1991 Kx 125
  5. KeyKeeper

    06 Franken bike Jetting

    Have a johnny cash bike (stole it one piece at time...didnt cost me a dime...) apparently. Main frame and motor are 06, subframe was an 05, replaced it with an 06 so my exh midpipe would have something to bolt to. My idle has been really funky lately with the heat (100+ days) so I built a heat shield to keep the carb cooler. On tight trails it hunts for an idle and that gets kinda nerve racking with bike constantly lurching, sure wears my clutch hand out quick. Pulled my air filter out to clean it and it had separated at the seam...whoopsies. So bought a new air filter and its still running funky at idle. Pulled the carb last night, figured the idle air jet may have garbage in it since its right there by the intake boot. Nope, its clean. So pulled the bowl since I didn't have a clue what pilot jet and MJ was in it. I know it has the factory needle and in the 4th slot. Was in the 3rd but I dropped it(the clip, not needle) one position to fatten it up and have it run a little richer (cooler). Well the main jet and the PJ are way too big based on the 06 manual. So for grins I got out my dial caliper and measured the bore on the head side and bam...its 41mm FCR carb. Supposed to have a 40mm on it. So downloaded the 08 manual and realized that the MJ is right on point for the 41mm carb. 178 but the idle jet is a 68! the manual says 42 is right, and from what Ive read everyone goes to a 45. So since this is a 41mm should I go with the 45 or maybe a 48? Not sure if the bore will matter since the slide will be closed most of the way anyways at idle.
  6. hey guys. i have an 03 rm 125 with jetting issues. i've jetted it multiple times. currently has all stock jetting (460 main,40 pilot, 3 down on clip) and i'm running amsoil dominator full synthetic premix. was running castor 927 but fouled a $30 plug which i'm not very happy about. anyways.. does my plug look alright? should i run a $30 plug in it? i'm not trying to get it too lean, and i'm not trying to foul plugs. 440 (next size down) is too lean. not sure what to do. this is how my plugs are looking right now. there not too wet, just pretty dark
  7. luke8500

    DRZ110 running rich

    Hi all, I have a completely stock 2005 Suzuki drz110 (same thing as a klx110) and it is running way to rich. It wont idle at all but will hang before it dies. It puffs a little bit of black smoke too. It always starts 1st kick and has decent power. Jets are stock at 35 pilot and 80 main. playing with the idle and fuel screws don`t do anything. Spark plug is black but it doesn't foul plugs. checked all around engine for air leaks with carb and choke cleaner and have found none. Air filter is clean and valves were just adjusted. Im out of things to try. Any help would be greatly appreciated. Thanks Luke
  8. Hello all! New to TT and the dirtbiking world. Just recently purchased a 2014 klx250s at altitude (5000 feet). I almost immediately moved down to 2200 feet in the desert. I don't know what pilot and main jets are currently installed but I can assume it needs to change as the bike is probably running really lean. If anyone has recommendations for what jets to use and other settings to change before I start taking things apart would be gladly appreciated! I don't have a very permanent garage situation so every tune up/part replacement I do I try to make a one day job. I brought the bike with a FMF Q4 Muffler and Power Bomb Header Pipe. Thanks!
  9. Like I said I have a 2008 KTM 450 exc. I live in Southern California along the coast in Dana Point. Riding is almost entirely all desert. So far average altitude is maybe 1-3k pretty much sea level to about 5000 ft is where I normally take it. Whenever I blip the throttle when stationary the bike dies. I’m trying to put some money into the bike to release some more power. I’ve gotten lots of recommendations: jd jetting, new exhaust system, gearing, suspension etc. so I want to get this throttle problem fixed with the right parts. Anybody care to point me in the right direction if jetting or jetting/exhaust is the problem for me ?
  10. Hey guys I've got a 2009 CRF450X with a RS-2 Yoshimura full system on it. I've had it for 2 and a half years now and its great, but since I put the Yoshimura on 8 months ago, it has not stopped backfiring on deceleration. I've played with the fuel screw both ways, and when I finally pulled my plug the last time I had my bike apart I saw white, so I turned the fuel screw out to give it more fuel. Didn't work. Actually seemed to make it worse. I'm beginning to suspect that I'm barking up the wrong tree, that there might be something else going on besides just jetting. The guy who owned it before me put a JD Jetting kit in there with a 165 Main jet with the red needle in the 4th position from the top. Maybe I'm overlooking something or maybe it something deeper. Help me Thumper Talk! -Kennedy p.s. I just had my valves adjusted about a month and a half ago
  11. Hey guys! Im gonna start out with posting all the information i think is needed for you guys to help me with this problem! Stock engine 2007 crf250r. Valve clearances are good and have JUST been shimmed with a double and triple check. Jetting is 175 main, stock needle position, 45 pilot and 50 leak jet. 1000ft above sea level. Im still having a terrible time starting and it used to be a 1 kick bike. I haven't changed my kick routine at all. 3 slow kicks, 3 throttle twist and then kick. Will sometimes start if i give it some gas when kicking. And then it starts 1-4 kicks after its warm. Im lost and dont know what else to look for. Thanks!
  12. So I have an 07 cr 125 fouling plugs before the bike even has a chance to warm up, plugs come out wet and oily on the tip. had both crank seals replaced last season because my main drive side seal blew. While it was split I had a new crank put in, we noticed my cylinder plating was pooched so I sent my cylinder off to be re-plated, put a new piston in the shiny new looking cylinder put the old warped head back on and called it a day. then rode it all season having absolutely no idea about the warped head because I overlooked it when I was excited to put my bike back together and ride. Its now winter, snows on the ground. I recently went to go for a put and fouled a plug before I could get to the end of the street and back. I was also smelling coolant so checked the rad while running the bike, lots of movement and tiny bubbes. Pulled the head off and sure enough it was warped to the point where I could rock it back amd fourth on the mirror and see a small gap... so NOW after I replaced the head my problems persisted and I can still see little bubbles swirling around vigorously in the rad if I rev it with the cap off, I've had boiled it down to my cylinder probably being warped then I found a leaky hose by the exhaust that was dripping coolant onto the outside of the exhaust port. Which brings me to what I think may be an incredibly stupid question, could it just be the loose hose sucking in air that is causing my rad fluid to have small bubbles in it? And maybe im just experiencing increadibly rich jetting now that my head is actually sealed properly? over and out.
  13. Hi I have read lots of similar topics on here and elsewhere, but couldn't find an answer that seemed to fit. I have a 2003 DRZ400-S with an old - style FCR39 slant fitted (now with Eddie mod for about a 1 second AP spray) as well as an FMF pipe, and the previous owner has attempted a 3x3 on the airbox but it is more like a rough 2x3. Air filter is standard Hiflofiltro oiled foam type. I live in the UK so altitude is more or less sea level, the air is fairly humid and the yearly average temperature is about 15C which is around 55F I believe, or average lows of 0C in winter and 30C in summer. Now, the bike doesn't exactly run poorly (now that I've just reassembled the carb after the pilot jet fell out into the bowl and the bike sounded like a misfiring Harley), power delivery feels fairly decent throughout the rev range but I know the carb runs quite rich. The best economy I've ever got can't be more than about 30 MPG. I have just done the Eddie mod and got the AP spray down from about 4-5 sec to about 1 sec so I hope this will help fueling. When I changed the spark plug the other week to a standard CR8E (There had been a CR9E in there) it was very black and filthy/sooty. Also the backside of the rear registration plate, which has only been on there about a month, is already covered in black splatters and sooty sideblast from the end can. Also, I have one of those R&D flex fuel screws attached, doesn't do anything even if you turn it all the way in. Main jet is 155 Starter jet 70 Pilot Jet 42 Sorry I don't know which needle - I took it out but stupidly didn't note down which, I know it was about 5 letters. If I cut out the airbox to the correct full 3x3 size, will this lean things out a little and have it running better? Or is it worth changing some of the jets down due to the fuel screw doing nothing? Any advice is greatly appreciated as I am a complete noob to carburetors and have hardly any idea what I'm doing! Thank you for any light you can shed on this.
  14. I have a 2004 Yamaha WR250F that the previous owner modified and the bike doesn’t run the way it should. It has an FMF muffler with an aftermarket pipe coming from the engine. There’s no other silencers or restrictions in the exhaust. When I got the bike, it was backfiring every time I let off the throttle no matter what speed I was doing. When the previous owner first started the bike, part of the exhaust pipe was cherry red while he was warming it up by giving it more throttle. I took the carburetor apart and found out that I have a 178 main jet, 40 pilot jet, and 72 leak jet. The needle clip was in the middle in the 4th position. I adjusted the fuel screw back to the 1.5 turns out position from the 3.5 turns out position the previous owner had it set at. I changed out the pilot jet to a 45 and the bike no longer backfires while I ride it but it does die when I leave it to idle. Sometimes it dies immediately after letting off the throttle and other times it will idle for a minute or two before dying. Now before this gets too confusing, I ran the bike with the fuel screw at 1.5 turns out and 3.5 turns out after changing the pilot jet. At 1.5 turns out, the bike would only run when choked and would die when idling. At 3.5 turns out, the bike will run with the choke off but will still die when idling. If anyone has any suggestions to try, please let me know.
  15. Hey guys i recently acquired a 2012 Yahama yz250f and i will need to be re-jetting the carburetor. I'm not really sure where to start on what size jets i will need. I ride between 7,000 and 10,000 feet in elevation.
  16. Suzuki_DR650SE

    DRZ400E Carb Question

    Ok, so I have had my DRZ for over 16 years now but for the last 2 years its been hell keeping it alive. I think its the carb.. but not totally for sure. I have rebuilt it three times in the last 2 years and keep finding junk in my bowl and jets. I have cleaned the tank, put in fuel filters and fuel lines.. I dont know if its coincidental but after getting my new tank from IMS its been down.. I asked them if the tank needed to be cleaned out prior but never got an answer. Its weird tho, each time I rebuild it I have to replace the pilot jet and the float valve and seat. It seems like it runs like new for one day.. but then its back to crap and not idling again. Just pops and dies.. then my pipe is glowing red hot.. I am about to give up on this thing. I purchased it in 2001 right from the dealer it had Calif License Plates and street legal. Love the bike when its running. So I have people telling me its my carb still.. I just took it out the other day blew it out with carb cleaner removed the jets and made sure all looks good. The carb is not leaking fuel so the float valve and seat are still good. I am thinking about buying a refurbished/rebuilt carb for 525$ is the best deal I have found.. But dang.. if that is not it I am really beating myself up good. Then someone from Kiehn said it was my Mid gaskets.. I am just really frustrated. If the replacement carb works I am going to tear this one down and replace the mid gaskets and go from there and test it.. if its good. then it will go on ebay and try to recoup my money back.. What do you all think? 2 years now if pulling that thing off and on and 3 full rebuilds.. Also I found this link on "How to DRZ400.." it shows a flat side like mine going on an SM model to swap out the mikuni carb.. I noticed one of the pics (see attached) shows to remove the Pilot air jet on the intake side of the carb.. why is that? Why do I still have mine(which I replaced every jet on the carb just back in November again). Also included is a link to it running and what it does, even with choke on its not as smooth as it used to be, DRZ Running Thanks in advance for any input.
  17. yam469

    2008 yz450f

    Whats the jetting for 2000ft elevation on a stock 2008 yz450f main and pilot to start with ? On my sidecar it has a custom pipe and exhaust
  18. hostile silence

    2017 Tc250 Jetting

    Trying to get some opinions on the 2017 Husqvarna tc250 jetting. I have 2.5hrs on the bike and 2 fouled plugs. Since switching from a yz250 and various 4t's, I have realized that my carburetor knowledge and setup is not what I thought it was. I'm currently at stock jetting and needle settings. If you have suggestions for jetting, air screw positions, idle screw from factory, etc. Please let me know!
  19. Hey I was just wondering if anyone could help me with jetting specs and proper premix ratio. I have a 2004 yz250 2 stroke with v force reeds, and a pro circuit fatty pipe. Mostly trail ride and hill climb with some track activity. Was wondering if anyone e could shed some light because it seems like I'm running super rich. Any help is appreciated, thanks!
  20. MNThumper250

    CRF250X Spark Plug: Jetting Changes?

    I'm tearing down my '06 CRF250X for winter prep. I checked the spark plug (see pics). I've rode with this plug for most of the summer. I'm thinking it's a bit rich, so for the other 250X owners out there, what jetting are you running/what do you think I should run? The only mods I've done is install the JD Jet Kit (165 main, 42 pilot, Red needle 4th clip, and thick o-ring), FMF Q4, and 4" x 4" hole in air box (with No Toil Super Flo Kit). The bike seems to run alright, but should I drop a few on the main jet?
  21. Hey All, I have a question about needle taper and how it affects fueling? 2003 DRZ400S (E model FCR39, 3x3, E Header with fiber wrap, Stock S muffler with endcap mod, and stock S cams). JD JEtting stage 2 Kit for DRZ E model, not for the S model with FCR Current Carb Settings: -155 main -Blue needle 2nd clip from top (DRZ E taper profile) -Coast enrichener removed -everything else stock E Carb settings (including slow jets, and air jets) -idle screw = 2 1/8 turns out (and idles perfect) I ordered the EMN needle as per suggestions from other TTers My Question: I was just wondering what the EMN needle would do to my AFR graph? The taper chart doesn't make sense to me. If you see the attached image, my AFR seems to be rich at 1/4 and 4/4. I believe the EMN needle will flatten/richen out my mid range. So, to compensate I also bought a 150 main. Is this a correct assumption? PS. Is the first rich state the AP effects? I know it's too rich because it's not a punchy as a pumper should be. I'm saving up for a leak jet kit/power bowl/AP cover, but was just wonder what effects to look for when I start tuning more in the next few months as funds become available? Thanks! Note: Blue is first run with needle clip in 4th from top. Red is 5th run with needle 2nd from top to lean it out. Note:
  22. idratherberiding

    KLX450 FCR Carb Setup

    2008 KLX450, FMF power bomb header, FMF Powercore 4 muffler, Desmogged, Air box top off 1000'-3000' altitude. 40 - 80 degrees Fahrenheit. Humid during summer I ordered the KX NCVR needle. What clip position should I put it to? Had a 155 Main jet, seems way too lean. Should I go 165 or 170? Have a 42 and a 45 pilot, not sure which to use with NCVR needle. What leak jet should I run for best throttle response/least bog? Currently have size 50 leak jet, I'm guessing it's stock as it has the Keihin star symbol next to the number. Float is at manual recommended measurement. Any suggestions are appreciated, thanks
  23. klxkid

    Spooge on IT175

    Just bought a 2 stroke, 1982 IT175, and it runs good but sprays out spooge from the silencer, and dribbles it out at the header where it bolts to cylinder. Bike runs good but may be a bit sluggish at low rpms. Not the the point where it bogs. just a little sluggish. From research it seems like it may be running rich. Wondering what I should try. Raise the clip of try a smaller jet? Running 32:1 right now. Any help is appreciated!
  24. Hi all I have a ktm 300 exc 2017, didn’t make any mods, and run it about 20 hours. Last two rides I noticed a knocking sound coming from the engine, that stops on high revs. I have checked all the common causes (that I know of): loss parts and clutch, both are OK. I suspect that the problem is related to a jetting issue, maybe a lean mixture, or maybe it is related to detonation. Did someone encounter this issue? Any ideas? Your help please.
  25. I rode around a bit reving it out then made a final hard pass before i removed it.