The SECRET to a FLAWLESS Carburetor!! | FCR Carburetor Rebuild Part 1
Вставка
- Опубліковано 10 лют 2025
- Come grab a coffee, get comfortable, and enjoy!
This will be a 3 part series, all of which are packed full great information about the FCR Carburetor.
Thanks so much for watching!!
Thank you so much, doing a complete rebuild of my brother's '08 yz450f. Couldn't do it without videos like these.
I'm only 7 mins in and I already learned 3 new things and I've watched probably 10 carb videos before. Great content!
Awww get out of here! Thank you! I had hoped this series would shed some new light on carbs. Sure I could spend the same amount of time showing how to clean a carb and tune a carb but like you said, there are already hundreds of videos on that. I wanted to cover the “other” stuff
Hey @NW Moto Garage. My FCR Carb goes through 2 work shops to ultrasonic clean and replacing KTM "Rep. Kit" (mid body gasket not included). That didn´t fix the problem (still runs to lean). After 4 Years of still standing i took the work in my own hands. After watching your video i´m absolutely thankful. Your knowledge fixed it. I ordered the mid body gasket kit , replaced it and my ktm 525 runs better than ever!!! Thank you!!! Greetings from Germany
One of the better videos I've ever seen regarding the fcr overhaul. This guy has a straightforward approach. He's very knowledgeable. I wish more UA-cam content can be as good as his.
Wow you are insanely nice my friend, thank you!!
@@nwmotogarage well of course. You deserve the credit. Thank you for passing along your excellent experience!
I second this! Fantastic video and I would NEVER have guessed that mid-body part. Thnx for posting.
Now I know that I likely have mid-body carb issue, that alone made this worth it! Thanks a bunch!
Did you have a mid body carb issue and if so what were the symptoms and did it fix it?
wow, puppy pads are such a good idea! wish I knew that before I changed the shade of my garage floor...
Thank you! I happened upon it by accident! We had some extra and I was intrigued by the absorption so I poured like 3 full glasses of water on it and then it hit me…. Hey we have all been there brother!
This video is simply awesome, so complete, not to mention the approach and details in the technical side. You’re a bloody legend in the midst of all fuel injection era people.
Good on you mate. Love from Aussie land 🇦🇺
Great idea with the puppy pad!
I just learned so much and I cant thank you enough. By far the best and most detailed carb video on youtube. I wish you the very best🫡
Coming from a pwk 28mm to this I felt kinda overwhelmed but your videos helped me more than u know..thank you!!
That’s awesome! Let me know if I can clear anything up!
I've been dirt biking for years and just found out 2 months ago about Keihin mid body gasket problem, I used to do rebuilds
and even JD hot jet kits and the carb still not be 100% correct since finding out about the mid body gasket it's been a 100% game changer on all 3 of my KTMs
It kinda slapped me in the face when I found out about them… it’s like a whole new world is opened up to you! Thanks for the comment
Thank you for making a video about this, the only one i have seen is from @Clayton Motos.
i have been struggling with my 08 YZ 250f for some time now with a bad bog of idle, replaced ALL the seals/gaskets/orings/accelerator pump in the whole carb except the mid body since almost no one talked about that, everyone just yelled that it was the accelerator pump which already was replaced. After having the carb apart for the 5th time in a year(what a pain it is to remove on this bike), it finally runs correctly after replacing the mid body kit!
That is such great news! Really glad you could get it figured out! I would say the part about checking to make sure the Excelerator pump is functioning by squirting fuel on the bench like I demonstrated is really important to. It’s pretty common for those to get dumped up as well but if this fixed it then that’s awesome!
great job explaining the carb in detail exact same carb on my 07 ktm 250xcf-w i think iv finally got it working good but now I'm Gunna order a mid body kit and go one up on my starter jet
Everything i need man, thank you sooooo much .
Best guiding video!!!!
Thanks for such a detailed 3 part on this! Gave me the confidence to tear mine apart
wow, excellent video, so good, your in depth knowledge and experience is great. smart guy
Thank you very much for this very detailed video.
Good stuff, need MORE! You got me itching to take apart my 2005 FCR now, I doubt it’s ever been done
If you do, stay tuned till the next two videos, lots of good stuff in there
In lieu of a JIS screw driver, in a pinch, you can take a #2 phillips and grind the point off with a belt sander and not strip the screw heads out nearly as easy. Not a replacement for the proper tool, but grinding the tip off gives it a full engagement into the screw body.
Less goo another video. Keep it up!😁
You’re the best!!
What way do i need to put the rubber o-ring around the vacuum plate? Does it need to be flush with the plate, or does it goes the other way around (kind of standing up - not flush)?
I have a CRF250R 2007, runs lean all the time, checked almost everything - from valves to tps, leaks, jetting, etc etc.. Just cant get it right for some reason. Also, throttle is sticking when it runs, looks like some sort of vacuum problem. When i shut the bike of, pull 2-3 times on the throttle, it comes lose again. maybe someone can help me here, thanks :)
I don’t use a FCR but my father has one in his 05 CRF450X. Like the video! Once that carbs done the bike will run clean!🧼
I can hardly wait!! I will be using the same jetting that was in it originally so if it needs corrected, I will be sure to document it
Brother.. noooooo 😱f*** me man I just built my first 4 stroke did a 1st gen to 1st gen crf450r /400ex hybrid and didn’t know removing the TPS would cause me issues. Is there anything I can do besides look for original marks or am I pretty much forced to get it on the dyno and get tuned?
AMAZING VIDEO THOUGH! You’re a natural teacher man, keep the content rolling!!
🔥 I really enjoy watching your videos, don’t stop
I certainly won’t! How have you been liking the shorts?
great video, thank You for that!
I allways use a little bit oa vaseline on my carb orings since it dissolves in gas anyway, but it helps the orings seat. Alse helps revives older lrings that leak when they get old cause it makes them swell the same way gas makes them swell. Good to be able to do in a hurry
this video is amazing thanks so much
Best carb video I've ever seen
Thanks so much!
At 1:34 in the video u talk about ktm using a different variant and I was wondering which exact one it is
Love the long form videos.
I shoulda watched this BEFORE I messed with my carb, great tips… now how do I fix what I buggered up? 😂
I’ve watched many videos on the subject and this on has actually explained how it works. Great content. Unfortunately I took off the screws for the electrical connection to the ecu. How can I fix it if it is messed up? Help!!!!
JIS screwdrivers! Vessel makes some great options, and they’re on Amazon, too.
If you screw in your mixture screw until lightly seated and the idle was still picking up while doing so, you need to drop down your pilot jet and continue adjusting.
Great carburetor rebuild video! Couple of questions. What did you use to clean the carburetor? Like what kind of solvent? I'm concerned about putting the carb in a solvent with the tps attatched.What did you do with the choke plunger is there an o-ring in it?
Hi, at 20:33 in your left hand.... what is that called? I need tp replace it but cant find it anywhere or even a name. Ive seen an athena 43mm venturi kit, but i dont know if that'd work on a standard bike. Any help would be great. 😊
I don’t know if I missed it but do you have links or recommendations on which kits to buy? Found a bunch on eBay but no idea if they’re any good
Hello from France, what's the website where I can find this rebuild kit please? An amazing video! You're the goat of carburator!
how do you get the accelerator pump needle on the side of the carb back in place? sorry if I missed it in the video somewhere
Well there's my problem! Having lean issues at idle
Thank you brother!
What is the baseline setting for the throttle slide gap height?
Hey did that carburetor throttle shaft have 2 washers on it ?
Hi, great video! What complete rebuild kit did you buy from All Balls for the carb (mine 2006 RMZ450)? Searching but can’t find the exact part codes. Cheers
You missed to remove the floating needle's brass seat , underneath that there is a metal mesh usually dirty.😉
How do you take them out without damaging them? They don’t sell a replacement needle seat.
How many parts need to come off before the carb can be removed? I remember my 2 stroke was not much, but my kx250f seems like it will take more disassembly
Hey mate, I’ve had some trouble finding the mid body gasket that actually fits my fcr carby. I believe it’s an 07 model and I’ve bought 2 07 kits and neither of them fit, any suggestions?
I know this is an old video but I have a question you might be able to answer. I have the same carburetor and in my bowl I have a chrome plate / liner in the bottom of that where I don't see one on yours. It's making it kind of difficult to clean the bottom bowl is that removable? I'm guessing it is saying that yours doesn't have one I'm just trying to make sure if I'm doing something wrong. Thanks great videos by the way
Rad vids man... I am truly ng to diagnose a hesitation @ 1/8 th throttle on my old Yamaha that has the same carb....
Have you tried the o-ring mod on the accelerator pump?
I guess I should ask what yamaha?
You have an tricks on getting the o ring and washer out of the fuel screw hole
Thinking of using a dry wall screw and filing down the end so it does hit the port
I use a straight pick that I have modified to have just the smallest hook
I have a atv Kymco 700mxu. What i think is the carburator, doesn't look like that. It has the gas handle valve that opens en close but it looks like everything is electronic because there is no flote valve etc ...
Hello from România. My carbureator has a problem and need changed. Can i put one from a 450 if mine is 525? They look the same. Îs there crucial diference?
I have a ktm sxf 250 2007 and it have a fcr 39 carburator it works fine the bike starts very well cold or hot but when I acellerate and drop it it keeps acellerating, not full accelerating but the idle rpms are too high I have to accelerate again for it to drop to normal idle rpms!! My question is if it have some parts inside that are spent And don't fit well!! Or some gigler that needs to be replaced!!
My nozzle from the accelerator pump is clogged, do you happen to know the diameter? Maybe I could drill it out. I tried to screw it out but seems to be pressed in. Not sure what to do here. Any good advice on cleaning it out would be appreciated. Thanks.
Look up welding tip cleaners and try those. Very small pieces of wire
Hi! I hope youll reply my man in just subbed. I feel like the bike could go much more agressive, but it doesnt. Whole carb is perfectly adjusted, valve clearence ok, everything. My bike feels like it looses power in top end, when it shouldnt. Can that black electrical thing cause this, that i didnt put it back exactly like it was?
l have a ZY 450 F with similar carb but l cant change the needle valve seat as it pressed in can l some how change the seat , l see different FCR mid body have removeable needle valve seat , not sure if l can change the mid body so l can change the seat , l do not see listing for the seat on my model and havent seen mid body listing with valve seat to purchase , thanks for any tips
I believe I answered this on the other video comments! Thanks !
what if you loose position of this screw? What is the standard setting?
Could you please send a link where to find all of the packings ive been looking evrywhere and cant find
Is there a full set of gaskets and reabuild kit for fcr 33 in one pack?
@3:27 you are showing the accelerator pump nozzle squirting fuel onto the pad. That little brass nozzle that actually does the squirting into the air-inlet chamber… where do I find that? It’s not included in any rebuild kit I can find… it’s not threaded like most jets are. I have removed it from my FCR, it almost just pushes in place. Mine is completely plugged up and blocked. I would suspect I need a new one.
There are no replacements. Use a single wire brush needle and punch through the corrosion
I have the same problem, can’t just clean it out it’s solid. Let me know what you do to fix it. I may drill mine out just not sure what size drill bit.
@@nwmotogaragewas just gonna say. Ordered a mid body kit from all balls and nothing… it’s not in there. Got a tip cleaner tool, I’ll try that
Do u have a part number for all these gaskets
Wow the carb God,, need quick opinion please, Yamaha, Kehien carb, '05 WR450F runs great but pops alot on decel. 170 Main 48 Pilot air screw is 3 turns out, should I up the pilot to 50 maybe 52?. Thaaank u..
With it being a 48 already, I would look at doing these mid body gaskets. It’s running lean so it’s possible the valves are tight and need to be
Clearanced
Might as well do them both, since you will need to takeoff the sub frame to get to the carburetor in the fuel tank to get to the valves
@@nwmotogarage Nope,, I have the '05 carb swivels and or pops right out with enough room to kick a soccer ball through it🤣
@@seatime674 🤣🤣🤣 that’s awesome, yeah they don’t build em like that anymore hahaha
@@nwmotogarage Yeah roughly starting in '07 all makes started the flat sloping aluminum frames that chopped off easy access to carb and top of engine..😭
I'm a bit confused though, people say popping on decel is a lean condition and to go up on pilot jet size when popping is actually unburned fuel from being rich which should require a lower number pilot, Also to turn air screw "out" which is richer so what am I missing here. 🤔
I have a problem with my KTM 250 2T
The tool has not been used for almost a year
This week I found time to take care of it, I did a fuel-oil change, I cleaned the filter plug, everything, finally I tried to start it, but the car could not start.
It only started with carburetor spray and shut off straight away
From that I understood that the carburetor needed to be cleaned and that's how I did it.
Now the problem is different, the motorcycle engine goes straight up to very, very high levels
I played with the air-fuel screw but unfortunately it didn't help.
Is there a situation where the problem is different? Something in the carburetor maybe? need help please
Where did you get the rebuilt kit from?
Is their way to fix if wen don't have access to new seal
I bought a quad with an fcr which isnt factory for it. I know nothing about these. Your video has helped me a ton!
Is there only one version of the Keihin FCR? Mine looks slightly different than yours. And where do i find that all balls mid rebuild kit at?
Hey! So, I’m curious as to what carb you have, can you email it to me? nwmotogarage@gmail.com
The rebuild kit is from RockyMountainATVMC. You might also try Motorsports.com
@@nwmotogarage just sent you an email!
Hi I've a KTM 250 exc f (enduro) yesr 2007 . Carburator is a keihin FCR. could someone advise me on what kit and where I can buy it. in the KT; spare web carburetor referenced as FCR-MX 3900G-TPS06. Thank you! I guess is a 39 mm
Do you have a parts number for the all balls kit?
what happens if i dont put that slide plate in the carb piston ?
can you send me a link where i can buy the rebuild kit please?
Keep these videos a rokin
Will do!! Thanks for the support!
Where i can get that rebuild kit?
Hey man had a question and you seem like the guy who may know. I have a Keihin FCR39 for a 98 Yamaha WR400. It was missing the accelerator pump rod. This is the “L” shaped rod. This thing is hard to find. All the eBay/Amazon sellers are all getting it from the same supplier (China) and are out of stock, till who knows when. I see that the old Keihin CV used on some Harleys has a “L” shaped accelerator rod and I have been able to find someone selling those. Do you know if the CV rod would work on the FCR-39? Thanks for the help and great videos.
Thanks for the email! Hope you have good luck with the Harley, please let me know so that way I can keep that in mind for the future!
What size/model carb is this?
Man, wow. What a complex carb. I just picked up a 2009 wr250f Yamaha, it has a high idle in my opinion. Someone has put in a jd jetting carb kit which seems real popular, but I’m may wind up tearing it down bc of the things you showed near the end of your video. Bet money that part hasn’t been touched.
The jd jet kit is nice because you get a different tapered needle and a few jets to “play” with. If you have a high idle, that most likely means you have too lean of a pilot jet, however there are a number of potential causes of a high idle
@@nwmotogarage yea went through the jets in the JD kit and looks like they used a 178 which the manual says to, located here in Arkansas so that should be about right. I just picked it up last Saturday, test drove it and bought it. Got home, tore down to frame to clean and now putting it back together. May have to see if the idle screw that sticks out the side could be the culprit too tho.
@@keithphillips1234 that 178 is the main jet, you need to adjust the long and skinny jet, the pilot jet
Bro!! this video should serve as the New Testament bible for the Thumper generation. When I bought my first 4T after only knowing 2T life (KTM 250F) - I was crosseyed rebuilding it to remove the turrible green scale left behind by #ETHANOLSUCKS gas. You hit on THE two points that I swear by for carbs: compressed air and JIS screw drivers. Mind was blown when I discovered JIS. "whoaa, so THATS why float bowl screws always got F'ed!" . Real talk? As much as I like to think I know - had zero knowledge of the mid body stuff. This is golden knowledge bombs. Really looking forward to Part 2! Can you address the "free accelerator pump mod" ??? Something to do with wire tie is all I recall. Please don't stop grinding on these vids! The universe and the algorithm will sway in your favor ;)
Holly smokes my guy!! Thank you so much for all the kind words!! The video itself is already filmed and edited and I didn’t mention the wire tie. But now that you mention it I will have to demonstrate it on my YFZ that I have in a future video!! And yes, I reeeeealy need those algorithms on my side
yep, mid body gaskets get old, will squish and shut the air fuel screw circuit closed
What bike does this carb go to
What brand is the kit?
This one is from All Balls Racing 👍
How many hours you think it would take from Start to finish?
I can do it in under 3 but that’s because i have done several mid bodies and 100’s of carbs, so probably 4 hours once you get your bike on the stand
And that’s no to say it’s hard for you to get the bike on the stand, just like as a starting point
Good video but... at crucial times showing jets your rush through. Please slow down at these critical descriptions and even show a pic of the jet. Example at 12:00. I am learning a lot just need you to slow and be specific at certain points. Thank you
Agreed, same with the music over the top of him talking.. Otherwise seems on point, and I do appreciate the tips and tricks as I’ll be attempting to rebuild my carb out of my yz450f
Can i have a link with the gasket kit?
where does one get these gasket oring sets as shown
I purchased mine from either RockyMountainATVMC or Motorsports.com but they are both from a company called All Balls Racing and you can get it from them directly online as well
this was so good. you covered it all. but the real take away from this was something totally new to me, a tip that can save alot of ppl alot of grief if theyre lucky enuff to come across this very excellent educational fcr 39 video. the main take away for me, its all very good but im talking the ahhhha moment that changed my life, was the discovery of the screws and screw driver tip.. it got to the point that i had to use needle nose vice grips to remove the secrews. now I know thats because I was n't up to speed that those arent your regular screws tand a regular old shitty american screw driver made in china isnt going tio turn those screws. ii eventually switched em akl to little hex screws but I have another fcr i use for a parts carb or my fcr for a drz400. its a real deal not a shitty clone off amazon. iv seen emon ebay for a $1000 bucks. wtf is that all about. ? crazy. thanks man fr this . seriously great stuff
I have a question for anybody to answer, is it normal for the throttle cam/ shaft to get stuck turning it all the way by hand without the cables attached to it and have to manually release the black handle with the spring under the shaft? Please lmk
Link del kit ?
Where or what is the numbering of the repair kits?
does anyone know the spec for the “nipple that shoots gas into the engine”???
Can’t you add the link to the puppy pads!?
Damn i screwed up doing mine, at least i know what i did wrong but sad i cant go back in time😂
Oh no! What happened to yours?
@@nwmotogarage it runs only on choke now, but! Its leaking because i broke the gaskets, then i saw the weld on my alternator cover just broke off i dissassembled it and broke the gasket on thiss too😆 so from fast thing changed into lots of parts buying. Soooo i have no idea how will it run
@@nwmotogarage also by screwing up mine i meant dissassembling the throttle position sensor (thx for awesome video too, at least i know what i broke :b)
Ît s diference fcr 39 and fcr 39 mx ?
Why didn’t I see this first! Mine still won’t idle after ultrasonic cleaning and rebuild and I didn’t separate the mid body . So stupid.
Can I just pay you to rebuild mine? :-)
Me, too!!
See I still have the hanging throttle and no idle. And when I can idle I hit the throttle and still has a hanging idle after changing the mid body seals. I’m so lost with this carb now and my 250f
Why not just do a full disassemble and then toss the parts into a sonic cleaner?
Anyone ever remove the accelerator pump without pulling the carb?
If you loosen the band clamps and swivel the carb, I think you can get to it
@@johnwatson3400 I did it without loosening anything. It was a pain but definitely easier then than removing the whole carb again
all balls did not include a safety torx with my rebuild kit
damn
Name song?
Unfortunately the road version of the FCR had a very different mid body gasket ring set up. I don’t know where any are available. If anybody does know please leave a comment.
The vent hose with black plastic t piece . What can I do if plastic snapped
Fortunately it’s not a critical pice that effects the way the bike runs. None of these hoses are vacuum lines so you can either run two separate hoses or leave it off. Thanks for the comment!
Really? The mid body is where the majic is...lol ok. Not a clean properly jetted carb huh. Ive never seen those seals go bad. Easily been through 1000+ carb cleans/ jetting