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Found 22 results

  1. RandallNV

    Did I mess up?

    My carb was leaking from what I deduced was the top cap gasket so I went to my local shop to get a new one. Of course they don't have it in stock but the guy suggests just slapping on gasket dressing/sealant and I'm in no position to argue since I'm both cheap and the opposite of knowledgeable when it comes to bike carbs. Two days later and it's still tacky (in appearance) and to the touch. I'm not sure if I should call it quits and put an actual gasket on or wait it out. Or really even if it was a viable alternative to begin with. Any guidance is appreciated. Side note: the tube says it's fuel resistant and good to 500°. Not sure how much pressure a bike carb is subject to though.
  2. My girlfriend and I have been rebuilding this one bit by bit. Backstory: We got the bike last summer as a project. It belonged to a motocrosser who didn't have time for it any more and let it sit for a while. We took the carb completely apart and soaked all the metal parts in cleaning solution. Pretty much everything metal in there was gooped up and everything rubber was brittle and flaking. All the parts that could be scrubbed out were- no metal was used to scrape the inside of metal, so that's not going to be an issue. We put a Motion Pro rebuild kit in to replace all the nasty bits, and that part is going okay. I had to order a new accelerator pump diaphragm, because that was completely toast. Two questions- 1.) The flat slide no longer slides cleanly through the carb body. The vacuum plate doesn't sit flush any more. The rubber o-ring on the roller plate looks okay, but the vacuum plate also has an o-ring on it. I didn't know about that when I put the plate in the cleaning solution. Is there a way to get a new o-ring for the plate, or do I need to order a new one? I'm hoping not to spend $100 on a new part if I don't have to. https://www.ebay.com/itm/Vacuum-release-plate-seal-Keihin-FCR-MX-flatslide-carburetor-37-39-40-41-NEW/191533918039?epid=16002473425&hash=item2c984fa757:g:gUgAAOSwq~tZQ8L1 This looks like it should work. 2.) I had to remove the throttle position sensor. Apparently, that's not something you should do because it's synced. https://www.dirtrider.com/features/protips/141_0707_keihin_fcr_carb_rebuild#page-45 There wasn't much I could do to avoid that- I didn't want to dunk the TPS in the cleaner, and the whole carb was gummed up with so much nasty stuff that a toothbrush and Simple Green weren't going to cut it. Is this something I'm going to have to take to a shop to have them redo? Is there anything else I should know, or any other useful rebuild tips? Thanks!
  3. Hello all, I have read a couple of threads on swapping the stock DRZ carb with a Keihin FCR 39, but it's primarily for the kits that are sold as new. I recently bought a used Keihin FCR to replace the one on my 2002 DRZ 400. The FCR was supposedly taken off a parted-out DRZ and I had the option of testing it before purchase, but without any disassembly (Seller marked bolts with silicone), meaning I could not check the setup. Surely enough, the carb came with the the necessary adapters to the engine and airboot, I already have an aftermarket plastic tank with non-vacuum petcock, so i installed and bike fired-up right away. The bike was idling fine but would bog from idle when opening up the throttle more vigorously. I had read that incorrect setup would lead to this, so i was satisfied that the carb was working and went ahead to buy it and open it up. Now i have a couple of issues preventing me from completing the final installation: 1. The throttle cables are too long. In the guides i have been reading it says the stock cables will work fine but not the case for me. Perhaps it's the combination of me having an older model Mikuni and older model Keihin, but even with bringing the housing as far out as possible, there is still 1-1.5cm (~1/2 inch) slack, which is totally unusable for riding. Unless i have made a serious error somewhere, it seems I need to get a shorter cables. Is there any difference between model years I should take into account? I can also get it custom made. 2. I attribute bogging to incorrect setup. I currently have an OBDXP needle with pin on 6th groove, 165 main jet, 200 main air jet and 60 secondary air. I didn't find the pilot jet but later saw that it was probably hidden under white housing and i needed to remove the bottom of the carb bowl(see pic). I suspect the carb was from a stock DRZ 400E, meaning flatside keihin and unaltered setup and probably has a 45 pilot jet. My bike has an open Leo Vinci exhaust and I will probably cut a 3x3 hole in the airbox in place of the snorkel. The bike is ridden usually at 1000-4000ft. If what I have cannot be used, what are the recommendations for the needle and jets to get rid of the bog? 3. On the choke side of the carb there is a something i think is called a coast enrichener. Is some hose supposed to be connected to top part running parallel to the fuel line (visible on attached pic)? Further to that, if the bog is still present after potential re-jetting, should this enrichener be removed from the carb? 4. There is a TPS on the carb, should I plug it into the bike connector? Many thanks in advance, Val
  4. Hey all, So I just completed an engine swap, got everything connected and got my battery charged, flushed out my old gas, emptied my float bowl, poured a cap full of engine oil down onto the cylinder, and put a fresh plug in. It turns over just fine and sounds healthy. I'm getting puffs of air out of the exhaust, and every now and then I'm getting some backfires and pops like it wants to fire. I've also tried bumping it down a hill just to see if the compression was low from some dried rings, nothing. If I give it a quick jab of throttle and the accelerator pump goes to work I get a thunder of a backfire, so I'm pretty sure the compression is there. I'm just kinda baffled that nothing seems to be doing the trick, the carb was in perfect working order attached to the busted motor before the swap. Only things I can think of are to check timing to see if its off a tooth, valve clearances (Even though I feel like if its minimally out of spec it should still run am I wrong?) and to completely clean out the carb Just wanted to see if anyone else has ran into this headache and what your solution was. Thanks for any suggestions
  5. Hi there, I just bought a Keihin FCR (I don't know if it is a 39,40 or 41mm) taken from a 2004 YZ450F motocross. I would like to know exactly whatI have to buy to make this fit on my drz, and how to know if it is a 39,40 or 41mm. Also, I would like to know which jet I should buy according to this : 500ft over sea level, 3x3 mod, MRD exhaust, KN air filter. Here are some picture of the carb. Thank you for your help !!
  6. Randy Sorensen

    Drz400 fcr39 jetting issues

    Hey guys. I'm having a difficult time getting my bike running right. I have the original drz, the "k" series, kickstart only. I just got this bike off Craigslist so I'm not 100% familiar with it but I will do my best to describe what's going on. It has a fcr39 carb, open air box ( not the 3x3 mod) full open yoshimura exhaust, cams from the e model, a k&n filter, a small stroker kit. My pipe was blue and bike is backfiring. Obviously running really lean. I am at 860 ft. Above sea level. I opened the carb up and saw the previous owner had a 60 pilot, 190 main, and the needle was at setting 5. I knew this was wrong, but I'm not an expert. I need a jet kit, I'm having a very hard time finding a kit for the bike, since it makes more power than most stock bikes, With all the power adders on this thing. Can anyone please help me, I just want to ride!
  7. NotBlueSteel

    DR-Z400E FCR issue

    Hi, My DR-Z400E had a broken vacuum line and was idling low and lumpy and then would not come down from high revs if I blipped the throttle. I fixed the line and now this is how the bike starts with the idle back all the way out. Cables are set well, throttle wheel is in the shut position. Any ideas??? Thanks, Brett
  8. Zach7018

    Another big bore question

    So Ive decided its time to pull apart my favorite machine and freshen it up, and I'm looking to make some improvements in the process. I already have a 3x3 mod and a JD jet kit done and it seemed to have changed the world. The stock bike just plain sucked and now its a lot better. I never expect 450 race bike power here but I know there is a little more and I'm wondering if the juice is worth the squeeze. I already plan to add a header and exhaust, an FCR39 carb and stage 1 hotcams. After some research it really seems like those places are where the gains actually come from, so would it be worth it to throw a 434 big bore kit at this bike or just stick with what I already mentioned and a new stock bore top end??? Also my rides are often solo and pretty isolated,how much of a reliability headache can I expect with these mods?
  9. rraiderr

    FCR39 Rebuild Cheking My Math

    I am in the processing of pulling my FCR39 and giving it a full clean after sitting all winter. Can you please validate my jetting is correct. Minnesota 700 above sea level. 2013 DRZ 400SM 3X3, MRD full system, K&N filter. 160 main jet 200 main air jet EMN needle clip 3 45 pilot jet Stock FCR pilot air jet R&D Racing Flex Jet Fuel Mixture Screw 2 1/2 turns from closed o-ring mod Thanks for the help.
  10. patq1996

    KLX400R (DRZ400E) Idle Issue

    Picked up a 2003 KLX400R a few months ago and since then I've been having some issue with my idle. At first, the idle seemed way too high so I turned it down and the bike would barely stay running, so I turned it up again. After doing that, the bike would hang revs and would take a few seconds to return to idle. I took the carb apart, and replaced the vacuum plate seal (since this has the FCR39 and heard that the seal could be warped due to carb cleaner). After doing that I was still having the same issue: the bike would still die on idle, regardless of how high or low the idle is set. Here is my question: what should I do to fix it? Is it possible that the idle air screw is set incorrectly? I set it to the 2.5 turns out that I've been seeing online, but that seems like it's either way too much or way too little air. The bike has the stock exhaust, and the 3x3 mod has NOT been done to it.
  11. Time Left: 7 months and 20 days

    • FOR SALE
    • NEW

    In stock, ready for immediate shipping! These are brand-new, Keihin FCR39mm carburetors with all the parts, hardware, & instructions necessary to convert your Suzuki DR-Z400. You may also add-on a flexible fuel mixture screw, JD jetting kit, and high-clearance fuel mixture screw for the ultimate in power, throttle response, and adjustability. Short of installing a big bore cylinder kit and cams, installation of a Keihin FCR MX 39mm carburetor on your DR-Z is the single best performance up-grade that you can make. If you've already made the 3X3 mod to your bike and added a performance exhaust, this kit is the next, logical mod to compliment the increased air intake and exhaust. More @ https://thumpertalk.com/shop/DRZ400S-SM-FCR-MX-39mm-Conversion-Kit-p2006766611.html


    Las Vegas, Nevada - US

  12. tplayer100

    fcr39 400s adaptor

    I got a fcr39 recently and bought a adapter kit off ebay. The air box adapter however looks like its a little off and some of the o ring is exposed, as seen in the attached photo. Think this will be a problem or should i ignore it. Was also considering just putting some sealant over it. Thanks.
  13. Hi All, Rode the new to me DRZ400e (2001) this weekend. In the woods. What a kick. I can understand why these things have a following. I have a question, that may be answered somewhere in the forum but I have not found it. I have this issue where if put the engine under a load between 1/4 to probably 1/2 throttle . . . like climbing a hill . . . . when I chop the throttle at the top, it pops and it will stall if I do not gas it. Does not happen so much WOT, like getting gears down a sandy straight. So I have a lean condition caused by something . . . . - Not the pilot jet or fuel screw as far as I have read . . this bike will start with no choke . . . so if anything I am borderline rich there - it will do the lean bog when cold. I have not noticed it so much after engine gets to operating temp. So it seems like the AP is functional. - my two stroke experience tells me raise the jet needle . . . but but not so fast . . . . . . . . . could it be the "coast enricher"? Understand, I have not looked inside this carb yet, I am looking for a place to start. The machine still has the snorkel. I would like to get it back to baseline . . . . . and maybe leave it there for a while. So my questions are - would raising the jet needle a notch be a good starting point? I assume it is on notch 3 . . . . . . . - what could go wrong with the coast thing? . . . I have seen other posts where people put these in the parts bin . . . . . and change pilot jets. But why would the factory not have done this in the first place? - what is an EMM jet needle? I have seen these mentioned. Any guidance appreciated. Thanks
  14. drz2018

    FCR39MX TT Kit Questions

    Ok so my FCR39 TT Kit came in the mail & it has some instructions as well as the extended fuel screw & jd kit.. first: the jets on the carb match the jd settings but I'm pretty certain the fuel needle is different.. should I swap everything to jdkit parts or is the needle all I need? second: I've also read about the o-ring (size #78) or wire mod.. didn't see it anywhere in the instructions but is it something I still ought to do? Also, is the R&D Power Bowl2 a permanent solution to the o-ring mod.. meaning I wont have to ever put an o-ring on or replace them.. just put the new bowl w/ ap adjustment once & I'm good? also, anything else I should know? I've pulled the old carb out in the past & I understand what's what for the most part.. just not certain about finicky mods and what shits current..
  15. rraiderr

    Raptor Petcock Mod Question

    I just did the raptor petcock mod and had a quick question. Running an FCR39 what happens if one night I forget to turn it to the off position? Here is the petcock I bought. So far I really like it. https://www.thumpertalk.com/shop/Yamaha-FUEL-COCK-ASSY-1-5LP-24500-01-00-p1000322768.html Yamaha FUEL COCK ASSY 1 (5LP-24500-01-00) Thanks for the help.
  16. 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:
  17. tplayer100

    fcr bog on jump landing

    Hey guys got my fcr39 dialed in pretty good. No bogging and runs fine on flat ground. But on landing a jump i get about a half second of bogging. I'm thinking the first thing i should check is the float height but wondering if their are any other cooperates i should be looking into. Thanks.

    Question About FCR39 MX Carb

    Hey guys, I just ordered the carb directly from Keihin and was wondering if you guys knew if it was a direct fit or if I needed to order an adapter for it. If I need the adapter then a suggestion on where to get it would be appreciated.
  19. Billy Harris

    Drz400sm fcr39 carb help

    I have a 09 Drz400sm I bought recently. It has a 434 big bore kit, stage 2 hot cams, fcr39, full yosh exh, and 3x3, I'm thinking the jetting may be off a little. It idles fine until I ride then eveytime I come to a stop it the idle hangs high for 5-10 sec. under a load it seems to pull hard and run great but at steady low- mid speeds it hiccups so slightly you almost mistake it for road bumps. I'm not sure the Jettimg in it but the guy I bought it from seemed to know his stuff. Any help would be great. Ives searched on here and almost been answered by some of the topics but I'm desperate. I don't want to hurt the bike if it's lean. Just need a point in the right direction. I'm a car mechanic and can rebuild this bike engine but inexperienced with carbs and jetting. Thanks
  20. Beerforkids

    DRZ400SM Jetting troubles

    Hi Hopefully i can get some help on getting my bikes jetting right. I have a 2012-2013 DRZ400SM. Mods are a Yoshimura RS3 full system, 3x3 mod, FCR39. When i bought the bike it had dual Yoshimura RS4 exhausts but i hated them so had my local bike mechanic switch to the spare RS3 system i had. He did the jetting which was a 165 main jet and a OBDXP Needle set on the third clip from the top. It ran alright but in third gear between 1/4 3/4 throttle at cruising speed 52-60km it had this sort of jerkiness like it wasn't getting enough fuel. I was told this was bog and getting a dynojet kit and putting the needle in would solve this. As per instructions i picked up the Dynojet 3111.001 stage 2 kit. Followed the instructions and put the clip 5 down on the needle and put it in. Bike wouldn't run right in second third or fourth gear at 2/3 throttle or under. Even bogged when trying to go pull the throttle and get up to speed. Replaced the mainjet with the one from the kit a DJ140 but that didn't much luck. Has that rough running at 2/3 throttle and lower and if i let off the throttle and get back on it would hesitate or act like it wasn't getting enough fuel sort of like when getting close to your reserve. I ride and live at under 500 meters with a average temperature in the 20-25c range. I'l be honest and say i haven't checked how many turns in or out the fuel screw is yet as i want to make sure my jetting is right then dial it as the screw is hard to access. Also the black tape over the hole in the first picture is where a black nub was that broke. Any idea what that part is? If any assistance can be given i would very much appreciate it. Edit the bike also idled fine with the setup i got it returned to me with a 165 main and obdxp needle. It ran fine at fourth and fifth gear.
  21. Setup: DRZ 400s with 3x3 airbox mod Old style slant FCR 39 with EMN needle on position 3 MRD Racing exhaust with quiet insert and spark arrestor. Problem: If I punch the gas the bike will cut out for a few seconds and then slowly recover. It is especially noticeable when I get on it hard and shift from 1st to 2nd gear. Also really bad if I climb a hill in 1st and then shift to 2nd coming off the hill. It will really cut out when I hit the throttle hard and then recover over the next several seconds. Notes: - I have done part of the Eddie mod where I zip tied the ap linkage arms together (there is a slight bit of slack so this should reduce/delay the pump shot slightly). - I did not grind the diaphragm stop down because I wasn't sure if I should. It has an aftermarket Boyeson pump bowl on it and I think that bowl may already move the diaphragm stop some. It may also make the shot stronger? - I moved the needle from 3 to position 1 (more lean) and it helped the throttle bog tremendously (almost doesn't cut out at all now during initial throttle) but the bike still cut out slightly and felt like it wasn't as smooth mid-WOT. What I'm suspecting is that I am getting too much pump shot initially which is flooding the bike when I hit the throttle. When I made the needle more lean (from 3 to 1) I think it made it better because the overall condition was more lean and the shot didn't flood it as bad. Questions: - Could the Boyeson pump bowl be causing too much fuel to be shot and causing a rich condition on initial throttle? - Any tips on how to move forward? The carb is such a huge pain to take off so it makes troubleshooting insanely difficult.
  22. Ok so quick overview of what I have here: 2007 DRZ 400 sm with about 31 000km on it (about 19000 miles) with limited edition plastics. I'll post a photo for good measure. As far as performance mods go, I only have an aftermarket slip on. It's a Scorpion Exhaust, I wouldn't even be able to say what model as I can't find it online… It was put on the bike by the first owner and it loud as &%$#@!. He said the baffle fell in when one of the welds broke and he had to take it out. He gave it to me but I can't put it back on. Anyway I love the bike and it starts fine with the starter on and then runs fine, except it sometimes stalls if I blip the throttle really quickly, go figure why. It also backfires a lot on deceleration with this exhaust… I've had the bike for about 7 months now, put about 4000km on it and love it. I think it's time to start getting some performance mods to make it run a bit better and make it more fun. I was looking into the 3x3 mod and JD jet kit for the stock carb and saw that people were heavily recommending to swap the carb for a FCR 39. I'm not planning on spending nearly 600$ on a new carb but I checked on our equivalent of Craigslist and found an FCR 39 that came off a 2008 KTM 530 exc-r for 200€ (about 235 USD). First of all, would that be a good fit for my DRZ? I read there are a few different FCR 39 type of carbs. I know I need some parts to make it fit the DRZ and found this kit for 93USD but the shipping cost to France is 60USD… That would bring the FCR swap to about 330€ (a little south of 400USD). Is it worth it? Do you guys think I could find an adaptation kit in Europe? Also, I think I'm gonna get the Yoshimura RS2 full exhaust and I was wondering what kind of jetting I would need in the FCR to run smoothly with that exhaust and the 3x3? Thanks!