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Found 42 results

  1. 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.
  2. thnksno

    Merge Spring Installation

    How do you do it? I have the old spring out and have hooked the Merge spring around the arm. Either I'm weak as a girl or that spring is too thick. Also as you tighten it, it binds on the post and then you can't fit the plastic lever into it. There has to be a trick, otherwise this is $20 wasted and I'll just re-wire it.
  3. 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
  4. Joe_B

    FCR gurus

    Is this carb going to work OK for my FCR swap? I picked up this 39 FCR from an eBay seller in China. The guy had perfect feedback and communicated well, so I took the chance and bought it. It is new and unused. By the numbers stamped on the body (3900K eaf29) it was originally from a KTM 250 XCF-W USA.
  5. rraiderr

    Lean at Idle

    I am running lean at idle and adjusting the mixture screw will not resolve it. I get a hanging idle and 99% sure its lean. I did the side cover off vs on run and no effect. Outside of the idle the bike runs strong especially on top. What should I change to add a bit a fuel at idle range of 1800-1900 RPM's. My Setup is below and I have a Full MRD and 3x3 and K&N. 160 main jet 200 main air jet EMN needle clip 3 45 pilot jet remove pilot air jet 2 turns fuel screw o-ring mod R&D Racing Flex Jet Fuel Mixture Screw Thanks so much for any help you can give, I am struggling.
  6. ericsXr600R

    EBay New FCR any Good?

    Hey guys, I put a Mikuni TM40 on my XR600R and really like it, but I always wondered if the FCR might be better. I ran across this EBay listing for a new FCR style carburetor. It doesn't show as a Keihin brand. Anybody buy one of these yet? Its a good price but I won't buy if the quality isn't there. I bought another XR and thought I would try an FCR on the new bike so I have one of each. https://www.ebay.com/itm/Honda-CRF-450-R-CRF450R-Carburetor-Carb-2002-2008-NEW/122835304977?_trkparms=aid%3D111001%26algo%3DREC.SEED%26ao%3D1%26asc%3D20160727114228%26meid%3Dd8d46407b09b4518913684b5910695aa%26pid%3D100290%26rk%3D2%26rkt%3D4%26sd%3D253192404113&_trksid=p2060778.c100290.m3507 Any input?
  7. I noticed on my DRZ this carb nipple isn't connected to anything and it spurts fuel every time I twist the throttle, even with the engine off. It's a Kehin FCR carb from the enduro model. Photo here The bike runs mostly okay but I'm having a possibly-related problem where the engine cuts out when I blip the throttle, especially at low revs. I wondered if this carb port had something to do with it, since it's connected to the accelerator pump (which would explain why I can't blip it). Can anyone tell me what the port is for and why it's squirting petrol? Any help appreciated.
  8. I'll try and give the timeline as best I can. Got a good deal months back on a bike that had cold start issues, well starting issue in general but it got better while warm. Had some issue idling but it ran really strong when you got it up to speed. Tried cleaning the stock carb multiple times (ultrasonic cleaned twice, once by me, once by a shop) and it didn't really solve much. Checked valves and they're in spec, which it should have been for having 9k miles. Don't get me wrong, bike ran well but wasn't reliable enough while starting that I didn't trust riding outside of my local area. Bit the bullet and bought an FCR MX39 which was my plan anyways, and that solved quite a bit of the issues, but brought up more. Start is better but it still takes a while, especially when cold. Idle is steady but will drop and die if too low. I occasionally get this loud pop while trying to start, like gun shot pop. I also now have this hanging idle issue when decelerating or coming to a stop. I can fix it by blipping the throttle which then makes the idles drop. If my idle is set too low, it will drop too low and stall. From my research I think it's a vacuum issue, which is weird cause the tubes are all there and the petcock vacuum is plugged. Took the throttle cables off to see if they were sticking and causing the issue but the video proves that's not true. I also checked for any air leaks near the boots, not it. Pulled the carb last night and only checked the slide but noticed this wearing on the top right corner and this super odd bubbling on the pressure plate. For the start issues I've heard bad CDI, but I'm not sure. Anyone have any suggestions or help they could provide? I promise a beer on me if I'm ever in your area! Video 1: https://drive.google.com/open?id=0By7xlw5wWOLHRVNfbGhCcUxmWXc Video 2: https://drive.google.com/open?id=0By7xlw5wWOLHaFVrRnlXcVpQSFE
  9. idratherberiding


    Seeing some videos on 70 vs 35 leak jet. What is the best accelerator pump setting for crisp throttle response, no bogging when you twist throttle fast as you can? Right now my screw that touches the black accelerator arm is only out 2 threads. There is lots of play on the black plastic arm in the opposite direction. Here's some pics and video of the current setup. Thanks
  10. ClutchinChrisG

    slant FCR mid-body gasket replacement

    I've decided to attempt the mid-body gasket replacement on my vintage 2000 slant FCR carb, stock on the DRZ 400 E. If you are like me you have scoured the forums for info on doing this service but found maybe 2 or 3 pictures of a taken apart FCR, dead end threads, and tons of negativity. BUT! Is it really that difficult of a repair to perform correctly? Well I have had my carb on and off at least a dozen times, trying different jets, cleaning, etc. For the last 3 years I've been getting by with the coast enrichener circuit bypassed to at least get enough fuel in the idle circuit to run ok. But it just wasn't working anymore. I could clean the carb out and get it to run for a little while, but after sitting it wouldn't start again. I tried ordering a refurb FCR-MX over a week ago and the guy has gone MIA and nothing shipped. I ordered from keihin-fcr.com. I would advise avoiding... But will update if I hear back and he has a decent reason for the delay. Anyways, it made me seriously look into the "unserviceable" midbody gasket. I mean, you can buy the gasket here: https://www.ebay.com/i/401380298480?chn=ps So today I ripped the carb apart again, but this time to the very last fastener, separating the carb bodies. I even found my smoking gun, in the one picture with the hoop thingy removed you can see the gasket has expanded and spilled into a passageway. This passageway leads directly to the pilot jet, blocking it's flow. Though as you can see every rubber piece inside is completely trashed. Which makes sense, do you really expect these gaskets to last 20 years? Or in this case 18? If you have taken apart your FCR and went, wow that fuel bowl gasket is recked yo! I need a new one! Well you can bet your mid-body gasket looks the same. Really I see no reason I couldn't get this sealed back up with a new gasket and some fuel-proof RTV to replace the epoxy seal around the edge. Why wouldn't it work? Just doesn't make sense to me all the negativity you find toward this repair.... But I haven't finished yet so who knows if it will actually work on the bike. But I think it'll run like new when I'm done. I hope it works out for me and I can inspire some others who would otherwise be forced to buy an 800 dollar carb to do this repair instead. Wish me luck!
  11. Hi, I already posted about this a few months ago. I wasn't sure what the best option was to upgrade my pretty stock DRZ400sm (only has aftermarket exhaust for now). I'm definitely going to be doing the 3x3 mod in the next few weeks but I'm still hesitating between buying a JD jet kit for the stock Mikuni carb or buying a used fcr39. I have 2 questions the answers of which should help me decide. On the local classified, there is currently a 2002 ktm 400 exc FCR39 for sale for much cheaper than the price of the kit on TT (also I'm in Europe so anything I buy on this website is going to be really expensive to ship my way). Does anyone know if the 2002 exc had FCRMX or the older model? Will it fit the DRZ? If I decided to pull the trigger on a used FCR39 (mx or not), are you guys aware of anyone doing a decent conversion kit? On TT I only see the entire kit including the carb, that I would obviously not need if I got a used one. Thanks!
  12. SuperMotoFreek

    FCR 39 mm for the Canadiens

    Hey there! I'm looking for a FCR39 to put in my 2016 DRZ400sm. I find it hard to find info on this topic. I want to max out the power on my bike and keep it reliable. I work for a Arctic Cat dealer and i have 3 clients how are looking to do the same on there bikes. can you guys help guide me? thanks
  13. Hi there, Completely new here to the forum but already read a lot of info! Just bought a very nice Keihin FCR 41 MX carb to go with my KTM 640 SM 2004. This sunday i'm going to fit the carb on the bike but need some guidance for the jetting. The bike now has: - Snorkel from the airbag removed and the top of the airbbox is fully open - Leovince X3 slip on (i sawed de DBkiller, without it's way too loud and with the full DBkiller i can't hear the revs...) So... how to start with the jetting? I live at sea level! I also have a Rally cam laying around, do i need to rejet when i put the Rally cam in? Thanks in advance!
  14. Wombat221

    FCR Slant Timing question

    Hey everyone, i was just wondering how do you adjust the accelerator pump timing on the FCR Slant Carbys, Thanks
  15. Kracker

    FCR MX 39, need help

    Howdy, hopefully someone can drop some knowledge on me. Please try to follow as im not much of a writer, im probably going to be all over the place....bear with me. I installed a custom "FLOWPRO" fcr mx 39 on a drz400sm :"3x3 & full GPR exhaus, no tps connected" WOT it runs and pulls perfectly, as expected. 1/8th-1/4 its sputtering like crazy or if im just cruising at a constant speed after a second or two it spudders until i crack it open. I had the A/f mixture screw and 2-3 turns out and it was sputtering like crazy anywhere from 1/8th throttle to 1/4th or just cruising at a constant speed. So i turned it all the way in and it ran much better, but its still happening, which leads me to believe it is too rich? I ran it without the airbox and it ran better that with it on there but not a significant difference. It has a new air filter and sparkplug looks good. It was running perfectly this morning with the mikuni on. Jetting spec: Idle jet #40 Main jet #155 Main air jet #200 Idle air jet #75 Choke jet #75 Needle ELQ 4th clip from top, "was on third but ran much worse, the guy that built it said to drop it one more clip to see if that helps, It did help a good bit but still not perfect" other than the spudder at 1/8 throttle and having to have the AF all the way in it runs great. WTF. I tried to give as much info as possible, let me know if theres anything i missed.
  16. Hello all, I appreciate the help this forum has given me over the past couple of years. I recently picked up an '01 DRZ400s and decided to do the FCR carb swap. I feel pretty confident that I managed to read almost all of the valuable threads regarding the CV to FCR swaps on this forum and others. Being a fairly competent mechanic, I opted to pick up a local FCR MX off of a YFZ450 from Craigslist. I've rebuilt quite a few carbs and I feel like I now have a greater appreciation for why the experienced group recommends people go for the new FCR swap kit or something that's off of a validated running bike. There are so many moving parts inside of the FCRs that are prone to wear, the margin for issues can grow pretty large. It was my first time inside of one, so I know for the future. Regardless, I have a used MX that was worked on with heavy hands and I'll do my best to make it run for me. Moving parts are in pretty fair condition as far as I can tell, but I'm having some issues with the rollers on the slide. There are 3 rollers which are fixed with bearings and 1 that's removable. 2 fixed ones with bearings have a little drag and you can feel that the bearings have some wear. It's not terrible, but I'd like it sorted while it's opened up. Prior to replacing a slide, my questions are: Could these bearings be gently removed and replaced with the rollers that don't have bearings? https://www.jetsrus.com/individual_parts/021_027_su.html Are there replacements for just the sealed bearings? I assume you'd have to take measurements and just find aftermarket ones, which is likely not worth it at all. Has anyone found any good tricks for cleaning these bearings? I believe they're sealed, which is generally a tough one to fix. I've heard of people soaking sealed bearings in solvent for 24 hours and then heating the bearing before spinning the solvent out. Thanks for your help,
  17. Dix_Dark

    Do I need FCR 39?

    Hi. Sorry for bad english. So, the main question is "Do I need FCR 39 on my DRZ dirt-adventure build?" I have(well, I will) the next mods: Hot Cams Stage 1 IN&EX + FMF Q4 + FMF Power Bomb + K&N Air Filter + 3x3 mod Everybody everywhere says that DRZ needs FCR 39(or even 41), but I find a downsides: lower MPG(it's kinda important for adventure), and abrupt acceleration, which may cause a wheel slip on mud or when climbing a hill(I know that I need to better control my hand on throttle, but usually I'm busy enought with the terran...). Considering all of this, maybe it's better for me to buy something 38-39mm, but without pump(well, I always can disable pump on FCR if I don't need it, but if I don't need it at all, why not buy something without it, and much less expensive, right)? Also a little sub-question: athena big bore 440cc worth $600 or not? I think that 35cc over stock for $600 is a little(yeah...) expensive, and makes little sense...
  18. luke8500


    hi all, i have a 2007 Honda crf150rb that has an unsolvable hanging idle. bike has full fmf exhaust (powerbomb header and q4 muffler with spark arrestor taken out. you can turn the idle screw up and it will sit there and idle great but as soon as you touch the throttle the idle will hang very high and wont come back down unless i tap the kill switch a couple times. I have replaced the vacuum plate seal and installed in correctly and it did absolutely nothing. carb has been cleaned about 4 times before that. Jets are 135 main, 48 pilot and the others are stock. The throttle cables are not binding up i have checked this. I have tried the fuel screw turned really in really lean and turned out really rich. it made little difference except making it almost impossible to start. The screw is currently set at the factory specified 2 turns out. I have set and tuned the throttle position sensor to exactly what it should be. I've checked all around the engine for air leaks and have found none. Other than these issues the bike starts first kick and runs great. I feel like I've tried everything there is to try. Any help would be greatly appreciated. Thanks Luke
  19. I've just picked up this FCR MX 39 - hoping to fit it to my 2008 DRZ 400 SM. The PO tells me this came from a WR 426. I've trawled the forums here and that's answered a lot of my questions, but hoping someone can help me with a few unknowns... - the PO cleaned the carb in an ultrasonic tank. I'm not keen on these unless I know what cleaner was used - which I don't, so I'm planning on replacing all gaskets. Should I split the carb and replace the mid gasket? These are available from several sources including James Dean. A number of posters suggest this shouldn't be done... - The choke and hot start assemblies were fitted in the wrong positions (swapped over) I've corrected this, but neither knob will stay out on its detent (spring straight back in). Is that likely to be damage caused by the incorrect fitting, or just worn assemblies? - See the pic with the arrow I've drawn. (1.JPG) on other carbs I've seen this vent has a T-piece to which 2 vents are connected. My carb only has the one vent outlet here, but there is another vent out about 3 inches below it (below the coast enricher) which I haven't seen on other FCRs. No vent tubes came with the carb, so I'm guessing 1 tube on each? - Consensus is that it's better to remove the coast enricher. Is this simply removing the 2 screws and dumping the cover and the bits beneath it? Any holes need sealing? - Can the TPS be plugged straight into the DRZ loom? Any other suggestions welcome. I'm not a mechanic so talk to me in simple terms Ta
  20. I have a 41mm FCR-MX carb off a 2007 CRF450R, installed on my 2001 XR650L. This is the 'updated' FCR design with the larger bore, newer accelerator pump cover/diaphragm and a slightly different needle design. The needle has a little extension at the blunt end, making it impossible for the needle to fall through the slide, and also easier to remove when you want to swap the needle. It has one less clip slots as well due to the tab. Here is a photo comparing the two styles: http://www.pbase.com/jdjetting1/image/64622985 I want to run the NCVT needle, which I currently have but it isn't this 'newer' style. Just a plain ol regular Keihin needle. I'm pretty sure it will work just fine, I just won't have the convenience of pulling the needle out quite so easily. Can anyone confirm that the old needles work fine in the newer FCR? I have it installed now, so it does fit fine and everything, just not sure if the taper and rest of the needle will be lined up where it should be. Thanks!
  21. I took the carb apart to inspect why there was a small gas leak and when I took the accelerator pump apart the diaphram was ripped up And pieces of the rubber were in there it wasnt like that two weeks ago what did I do wrong? Was it in upside down or something? Im trying to figure out what is the right way so I dont mess up the new one some one please help is this the order it goes on
  22. Hi all, Was surfing the web for a FCR 39 or a likely alternative to upgrade my DRZ400 and came upon this. https://technologyelevatedco.com/ I've never seen this kind of carburetor before with no jets etc. The manufacturer claims all the regular stuff; more hp, better mileage, easy to dial in and so on. Has anybody here used one of these and can share their experiences? Is this just tosh (aka snake oil), or actually the best thing that happened to carb's since <insert preferred analogy here>? Other thoughts on this are also welcome! :-) Thanks.
  23. I currently have a 2015 DRZ400S with 5k miles on it. I have the 39mm FCR carb installed, the airbox mod, and the MRD exhaust. I am looking to do the big bore kit with a set of hot cams to probably finish off the mods that I plan to do on the bike. My question is, with this bike at this mileage, is it necessary to replace or change anything else when doing a BB kit and cams? or is the bike still new enough and low mileage to get away with just bolting the kit and cams on? I just want to do it safely without risking anything, but also do not want to waste money on things I dont need. Thanks in advance for the input!
  24. I’m currently at stock jetting on my 2003 yz250f. I’m rebuilding the top end with a 269cc big bore kit and installing an FMF power core 4 with megabomb exhaust. Current elevation is 700’ above sea level. Where should I start with my jetting? And where can I buy individual jets so that I don’t have to buy an entire assortment? Currently: 178 main 42 pilot needle is 4th Clip from top (stock)
  25. banditorama

    XR650l FCR 40 jetting problems

    I've been trying to work out this low speed jetting issue for a while now and am running into some weird problems. It seems like most of the bikes I see with this mod are running either a 42 or 45 pilot and now I'm sitting at a 55 and still having lean running issues. The bike will cough through the carb at less than 3 turns under 1/4 throttle on fuel screw. Above 3 turns it will run fine off idle but the idle sometimes hangs. As the bike sits it's running 55 pilot, 85 pilot air jet, ELT needle (NCVT equivalent) three clips from the bottom, and 165 main jet. Above 1/4 throttle the bike runs like a champ and pulls hard throughout the rpms/throttle position. With the 55 pilot I can set the fuel screw ~3 turns out and I won't get any cough back through the carb under 1/4 throttle but it has problems with the idle hanging intermittently. Anything above 3 turns out and the idle starts to drop and the bike will stall. I'm around 500 above sea level. Carb has a new vacuum release plate o-ring, completely cleaned out, hot start air ports rtv'ed shut, rd powerbowl 2. Another thing is I bought the carb missing the whole tps sensor (might be an issue) but I tested the open part where it should be by spraying propane at the opening and had no change in idle speed. I've got a 58 pilot on order but it just seems like that's big compared to everyone else. Any advice would be appreciated!