Great video. I’m going through an 09 YZ450F for a buddy of mine and his carb was in even worse shape. Thanks for pointing out the mid body gasket as I’d never pulled one apart and sure enough this one was clapped out. With todays fuel, now with up to 20% ethanol without them needing to relabel it, I got a tip from a former factory mechanic- put just a little bit of 2 stroke oil (250:1) in all of your fuel. It lubricates but also stabilizes the fuel much better than Stabil or Star. Since I started doing that going on 10 years now, I haven’t had a single carburetor foul up like what you showed here; plus a little valve lube and hint of the smell of the good ol days is nice.

I’ll try to fix my FCR carburator with your support of this video, greetings from Chile 🇨🇱💪🏽

I cant begin to explain how much this frickin HELPED!!!! THANK YOU THANK YOU THANK YOU! Couldn't find a single thing until this GEM!

yep did that mid-body gasket replacement 2 years ago for my 05 450X..bike has run perfectly ever since...i bet there are 100's of bikes out there that just need that mid-body done to run like new again

Thanks for the video bud !! My middle body gaskets were Jelly on both my Thumpers 01 Yz426 n 04 Ttx450r with FCR mod....Both bikes now RIP and idle Perfectly! Huge improvement from where they were at before especially the 426 I dropped in Hot Cams stage 2 both intake n exhaust w decomp, Valve adjustment, clean carb and New Mid body amd rebuild kit Jetted for Utah elevation.....So Happy with her now Fires up by 2nd kick and is almost twice as Fast as before !!!! Thanks again HIGHLAND CYCLES!! YOUR THE MAN!!!!

Just wanted to thank you for taking the time to make this video. Helped me out hugely. Liked and subscribed. Ride safe - from Bundaberg Qld Australia

I dunno why you got thumbs down. Maybe your cinematography? Anyway, great tip on the importance of the "mid-body gasket."

Ive never been so excited to watch a video but highlandcycles is doin it to me! Im trying to figure out what i got myself into buying this 08yz450f! I got it running, now its not running. HOWEVER, Im already knowing this brother and this video is going to help me with this. YEAH

I loved this video. My son has a 2007 KX250F and it is hard to start, terrible idle, and backfires on decompression - was running great a few months ago, but now to the point of frustrating him (and me). So I plan getting the complete rebuild kit along with the mid body gasket kit and see what difference that will make. As you also did, I will start with screw out 2 turns. I don't have an untrasonic cleaner so it will be a bit more involved in getting it nice and clean. I will also check the accelerator pump for holes or wear. If I am successful with the KX250F, I may do a repeat of this on my other son's 2007 SX250F KTM that also sports a Keihen FCR carb - it's only challenge is it is hard to start - but no idea how long it has gone without a good strip and clean. Keep up the great work !

Best video on the FCR carb rebuild for the real world. I left that shitty fuel in my CRF for a while and it gunged up the carb pretty good. (Worse than the one you show) anyways I knew I’d have to replace the mid body gasket and it was nearly impossible to find (I’m in the UK) but I persevered and like you show it was totally goosed. Also cleaned it all in an ultrasonic bath which is critical. Hopefully have the whole thing back together in the next few days. Awesome vid with a good level of background wisdom and knowledge that you share. Just subscribed. 💪💪

17:19 I feel bad for you son. I got 99 problems but my carb ain't one 😂

Great video, thank you! Just purchased a KTM 520 that has been sitting in a garage for 16 years. This video is exactly what I needed!

Great video man thank you!

Exellent video!! FINALLY someone's explaining and replacing mid body gaskets, my local KTM dealer was actually discouraging me from replacing those! Subscribed.

Great video, I just ordered a mid body gasket, and you have a lot of nice random tips for how things should be. I rebuilt my carb and everything looks perfect except the slide doesn't come all the way down so when I look through the intake port it's obviously up 3 or 4 mm's. The throttle shaft also doesn't rotate all the way back as it's a few mm's away from the idle screw. Any idea? Figured it out, the accelerator pump actuator was rotated counterclockwise about 90 degrees, the stop on it was on the wrong side of the throttle shaft. This probably happened when I attached the slide wrong and it snapped past it. Kind of a MF to get that all back together right with the spring tension!

So thanks buddy...I have this same carb off my 530excr. Anyway she's in my ultrasonic cleaner with FABULOSO, LOL. Doing the mid body also. All Balls had both kits. Only thing I missed is that slide round rubber piece. Can't figure which way it goes back on...Hope it runs!

Awesome was struggling with a idle issue . this nailed it great content thanks Morgan...thumbs way up👍👍👍

I just called you about that carb thank you for the advice brother wish I lived closer I'd have you do it the clowns around Pennsylvania don't know anything

Good info thanks for sharing

You are the man

Nice vid!

Great video thank you

@ 14:45 screw spring washer! U Rock

Great video brother, just rebuilt one for a friend and his kit didn't come with the mid body gasket. It looked ok, but doing some research I came across this vid and after reading your replies to some comments, I recommended he purchase it so I can replace the mid body gasket while everything is out! He's installing a bigger pilot and main (ones that came with his exhaust I think), anyways, you adjusted the clip on the needle and I'm just wondering if it's necessary. The new replacement needle that came with his kit only has 1 slot so I didn't use it, because the factory one has some adjustability. Just wondering what your thoughts are about altering the needle before actually testing the carb out 1st. Thanks!

Just a heads up on your ultrasonic cleaner. You dont want to lay anything directly on the bottom of the tank because it can damage the transducer that does the vibrating. You want to use a basket with small rubber feet or hang / suspend the object from above.

I have this problem were it works great with any level of choke on but when the choke is off it has a hard time just getting rolling without stalling. I have to rev it then it's at least able to run. Just ordered a bunch of parts to rebuild this carb. I thought I'd never get to fixing this but since the carona virus came to NY I got a lot of time to fix all my toys!

Good shit man only info i found on the mid gasket and how it can plug the holes. Im pretty sure it plugged my accelerator pump hole.

Thanks buddy

I have always wanted to split the carb like that but now that you mentioned that those gaskets wasn't available, now I am happy I never did split it but it makes sense why I couldn't ever find the issue with why my bike ran horrible, I always took it to a carb guy or Yamaha and they couldn't fix it and now it makes sense why my bike was running horrible, now I regret selling my bike man I'm bummed out now

Unless you have an mx steer clear of the early fcr slants

I used to use fabloso as well but I use pinesol now. Works much better. Peace

Great video. Do you need to dilute the fabuloso with water or pure fabuloso in to the ultrasonic? Thx

Hey, man! Love your videos! If an FCR carbed bike will start and immediately die. Something is up with the pilot circuit, right? Or can the mid block gasket you refer to have something to do with that?

Have always stored my bikes with empty carbies.. bowl nut off.. never have any greif. A week or months no sweat..

Hey man, love the videos and just subscribed. I am literally working on the exact carburetor for the same bike. I was curious if you had the link to those mid body gaskets. Also what do you suggest for main and pilot for 4.1k elevation?

Thanks for this video. About to do this myself. Have done the carb and bike still barely runs.

Hi i had a question about the midbody, do you know the name to the two brass tubes that are coming out of it? and where i could buy them thank you guys and i love the video!

Thanks M8, wish u were in Oz.👍

I purchased the allballs kit also. I am almost finished with my rebuild and I have a leftover small (7.6mm / 0.3" dia) seal that I can not find on the FCR-MX exploded view diagram, any suggestions? It is not an o-ring or u-ring, has a tapered outer edge and cupped surface on one side. My father-in-law use to say if you have leftover parts that you have to eat them, so at least it is small.

Great video. Do you mix the FABULOSO with water? Or just pour straight from fabuloso bottle? Thanks

Awesome vid thank you. What would your suggestion on jet sizes for a FCR41MX on a XR650R be? Full Pro -Circuit pipe and elevation sea-level to 1000ft.

Do you need to dilute the Fabuloso with water? Or straight from the bottle? Concentrated? Thanks. Great video

Hi again just a very quick follow-up question. I finally had the time to pull the carb off but noticed that the mid body section appears to be stuck together with some type of apoxy resin. Do you have any advice for getting the stuff off or should I just leave it?

Great vid! Is there an O-ring on the needle retaining bolt?

Excellent video. Mid body gasket not talked about much and my bike just didnt seem to idle right. More specifically if i use the fuel screw the idle would go up and down wildly with only small adjustments. Opened up mid body and gasket was horrible. Im sure bike will run better now. Thanks!

Hey man great video. Question if you know are all them mid body gaskets the same? Rebuilding a yz426f carb that needs this thanks.

Great video! Do you have links for the rebuild kit and the middle body kit for 2003 ktm 450 exc? (Fcr 39) Thank you!

2008 CRF 450r just went to do the mid body and it has 4 screws With white gunk inside and no hex or star to remove them. What should I do? Also what altitude are you at?

Question for ya swami!! 04 crf250x this accelerator pump injector nozzle little brass piece on my carb isn’t stationary.. had a hell of a issue recently where it turned and was squirting into the air box vs the intake.. is there a way to remedy this or do I have to split the mid body?

Does the all balls kit (26-1266) comes with mid body gasket ? Im having all kind of strange problems with my fcr and where i can find instructions for the kit

I have a fcr from a 2003 drz400, the mid body is epoxied on with something resembling jb weld. Any tips for removing this epoxy to rebuild the midbody??

Other than the nipple pointing towards the accelerator pump cover, is there any other orientation I need to put the accelerator pump diaphragm??

Thanks for another great video! On my son’s FCR the idle adjuster seems to be seized. It kinks up when I try to adjust it. Any tips for this issue? Thanks

Nice video, thanks! Hey, what ultrasonic cleaner do you have? I browsed around a bit, there's so many choices, not sure which one to go for. Also, how can I tell if my vacuum slide plate needs replacing? There is some play in it. Do you happen to know what the wear tolerance specs are for it? It's an FCR39MX.

Hey man thank you so much for this video. I rebuilt the carb on my 98 wr and finally got it to fire but it will fire and run for a few seconds then just die. When I pull the plug out it's wet and really fouled but after I clean it back off it it fires on the first kick. Will not idle and pops a ton but if I get it to rev up it runs great. I'm running a 45 pilot at 2500ft and everything you're saying is leaning me towards a messed up midbody gasket. Would that cause this problem? Also do you have any idea where to get a throttle cable cover that fits a kx250f just like this one? My buddy bought his bike and it didn't come with one on it and every one he's ordered has been the wrong one. Any help or speculation is appreciated cause this dang bike has got me stumped

Fennnnnnnnnnnntttttttttttaaaaaaaaaaaassssssssssttttiiiiiiiccccc job , Mite . 3:16

So another guy was saying the mid body gasket wouldn’t come off because there was glue in those screws/Allen head screw. Well I’m in the same boat. Can’t seem to get them off because of it and I’m stripping the hell outta the screws. Any suggestions? Also, a little off topic, but with the idle screw cable adjuster I don’t have a a spring at the end of it. Is that needed or can I figure something out like take a spring from the end of a pen and work it on there?

I have an FCR slant and am going to replace the mid body gasket with an All Balls kit. There is some sort of sealant on the outside of the carb at the mid body join. When you do a rebuild do you apply a sealant when putting the carb back together or is the o-ring gasket enough? Thanks heaps for the video!

I noticed you did not remove the idle screw or the tps before putting it in the ultrasonic cleaner. Is this ok to do? It won't damage anything?

I have a yfz 450 that runs good but pops on deceleration 170 main 48pilot with slip on do u think I need to totally clean/ rebuild the carb

Wearing those glasses, every carb will look green to you, Bro.

Have a 2008 YZ450F that sat for over a year. I drained the fuel from tank and bowl and did a straight seafoam soak in the carb while on the bike. It starts up and finally will idle with the enricher pulled out. She runs rough but if I shake the bike back and forth the idle gets better. Should I just break down and clean and rebuild the carb?

Morgan I totally forgot what I really wanted to ask you. I took the carb off inspected it cleaned it, and had put it back on and the only way to get her to go was with the choke on. when off, that sucker was backfiring and wanting to backfire like crazy. Then I had the hardest times getting her to start. The backfiring- is it because of carb cleaning or maybe the timing is off by one tooth?

Quick question ~ Did you have a spring in acceleration pump, which way was it assembled cheers Mark

2009 wr250f idle is erratic, slow to return back to smooth idle. Works for a while then it don’t. So doing a full carb rebuild on mine as well, main kit, mid section and accelerator pump kit too. Appears to be same carb. Should I be able to follow this video for good result as far as jetting or no. Here in Arkansas hot and humid in summers. Anyhow tried explaining to groups in Facebook this is why my shifting is problematic at times, bc, the idle won’t return to smooth and consistent at a stand still or during a ride which won’t allow the momentum of the engine and internals to slow down to allow for a smooth consistent shift. They disagree. But it only makes sense to me. But I could be wrong. Maybe you can shed some light on it for me. I’m ready to enjoy the bike and stop working on it trying to get this carb issue lined out. Any help or advice would be great. Thank you man. You do awesome work.

2001 KTM 520 - Why is there no check ball in the accelerator pump assy? Also there is a square brass piece pressed in a hole the pump should pull or pump fuel thru (I dont remember fuel direction) fuel can flow around the brass as it is a square in a round hole. Why is the brass in there? I am tempted to drill out the brass OR figure where a check ball belongs and add it. ---- I cleaned carb myself and I paid to have carb rebuilt with All Balls kit - it still aint right ---- I wonder about pump because riding, burping throttle, sometimes it responds and sometimes it does not. Idle is erratic, I turned idle up to about 1100+ rpm just to ride without stalling. All starting hot/cold/ choke/no choke sucks - no pattern but it always get it started. Valve clearance is correct, top end is good, spark plug is clean running, hauls ass on the gas. ---- I need consistent throttle for technical trails and idle and consistent starting. Any ideas? Check valve ball? -- Hey thanks for any ideas. I am about to tear into it soon myself.

What brand or style of carb would you buy for a 2006 YZ450F. For just average trail riding.

Congrats my friend and kind regards from Hellas (Greece) island Cyprus.. I have one YFZ450 model 2009 and I don't know how to adjustment the carburettor.. The needle is 6 rounds.! Is this normal.? The bike is standard.. Can you help me please.? Thank you and sorry for my English..

I have a 2004 yz250f with the same carb and has always ran good my throttle got stuck so I cleaned the carb left the float alone put everything back together and still throttle won't snap back it's gotten smoother but won't snap back and carb is also pouring gas out of the Drain line soon as I turn the fuel on

Salve dove posso acquistare il kit revisione per Kehin.ho un Fcr 40 da ricostruire grazie

Great information, but what do you do if you don't have access to an ultrasonic cleaner?

I like your knowledge about the KTM carb. Do you take carbs in for a rebuild? It's for a 2001 520 EXC.

I am running the fcr on my 01 yz426, what jetting would you recommend at 5500ft?

Does the kit come with the orings for the fuel swivel?

Wow what a big pain on the mid body gasket previously causing a new carb to be bought! I would widdle it out of a pc. Of rubber for a week before I bought a new carb. With the at home manufacturing tech out there these days hopfully those things don't happen much anymore.

What do you think about the dual spray accelerator pump nozzle? Will it cut out the bog at the bottom end?

How do you get the float needle seat out for replacement. My is damaged from ethanol. 10:18

my Accelerator pump squirter is angled wrong. hits the side of the carb not down in the head. can i change the angle. 06 trx 450

What type of grease did you use? Brand?

Hey highlandcycles. Great video on this topic. I have now rebuilt my FCR on my 2007 CRF450R. Got a question about jetting hopefully you can answer please. I live in Idaho at about elevation 5000 ft. My manual calls for stock settings 178 main 42 pilot 3rd clip position. Fuel screw 1 3/4 turns out. For my elevation and temperature it calls for 172 main 40 pilot 2nd clip position and fuel screw 1 1/2 out. So i set everything to 172 main. 2nd clip position. Left the 42 pilot in and im 1 1/2 out fuel screw. My bike fires up when cold so much easier with hot start. Harder to start with choke for some reason. Sometimes wont start at all unless using hot start. When it starts it runs perfect though, idles great and everything. Just wondering why i always have to use hot start? Kinda the same problem with a 2005 CRF250R that we have. Its all stock jetting. So like you did, should i up the pilot jets even though manuals call for smaller the higher elevation and hotter temperatures? I'd really appreciate your input on this. Thanks alot!

What jet controls idle i can only get my yfz450 to run on the choke and dies if i dont use the choke

Nice vid - I was working on my FCR tonight. Got a question . . . . . what is the hole in the intake bell next to the slow air jet?? Mine was filled with dirt . . . have been chasing some tuning issues . . .

Nice video.I have a 2007 Ktm SX-f 250 and when i run it, it starts fine in cold start and hot start, and when i push throtle it responds well but sometimes it take a few seconds to drop the throtle and keeps acelerated a few seconds sometimes i even have to give a litle throtle kick for it to drop the aceleration to the normal idle rpm.My question is what do you think it could be, my mechanic already disasembled the carb but doesnt find any problem but it keeps doing this.

Was that a MX carb or a slant body

Other videos seen to point to the slider wearing as a problem with these carbs? I have a hanging idle issue and it seems to point to the slider wearing, it has a plate that is designed to wear but they are over 100 to replace. Any ideas on a cheaper fix?

I'm glad I found this video because I just bought a 06 yz250f off a friend and it's been sitting for years and the carb was all green almost like coolant and I was really concerned. I'm currently waiting to rebuild it right now. Waiting for a few things. Also you brought up a good point, would you have recommendations for jet setting for the Chicagoland area? Since I'm in there I should make sure everything is proper and set up for my area.

Mid Body screws are they torx, allen, tamper proof screws,,what size driver as dont want to strip them out Thanks

So my throttle valve slide is getting stuck at the top when I turn the throttle drum. I am not sure if it is supposed to do this and I am just turning it too much, or if something isn't assembled correctly. To reset it I have to push the accelerator push rod lever and it allows the slide to go back down. Any tips or thoughts?

I put a FCR off a YFZ on my Z400 and running really lean and high idle no matter what adjustment to the idle and air fuel and jets, I pulled the slide out and noticed there wasn’t a o ring on the slide, I ordered a kit to rebuild it and having a hard time finding a mid body, would solely no o ring gasket on the slide plate cause high idle and very lean condition at high idle?

Will seafoam or any fuel cleaner get that junk out of the bowl? I'm sure once the goo sets in, some jets(like the pilot ) will already be plugged. I left gas in my FCR carb last winter, I had to clean it in the spring(me dumba**), I had a friend say seafoam might of worked, but I didn't try it. That mid gasket, I've not done that, thanks for the video?

Can I please have the link for the parts, my 06 beta 250rr could really use a carb rebuild

Thanks for information Im from indonesian

You put the main part of the carburetor with the throttle position sensor and wire still attached? That’s not going to mess anything up?

Any problem with the TPS in the cleaner?

I have a 2008 kx 450 and recently done the shims and replaced chain and all is good on engine side. Reason for my comment is that when I want to start the bike basically from cold start I have to use the hot start and with choke out then bike will start? However as soon as I leave the hot start lever or push choke in the bike simply dies! Since I have seen this video of the mid section carb being stripped I will also do the same and check those gaskets/O-rings out. (Note: I replaced all jets and the gasket set I could get from Kawasaki but not the mid section)

Do you know what way the gasket faces or how it goes on the slide plate? Flat side up? Or down?

you say the adjustable fuel screw is an upgrade, what is used in that hole when its stock? do you need that screw?

I have a fcr on my 04 YFZ. I have a problem. I think it passes too much gasoline than it should. Could a bad mid gasket cause that? The idle stays very high and i have backfire. Sparkplug is very black and it smokes a little. I’m sure i have the good jets

I have a 450 I messing with. The o-ring, spring, and washer are gone from the adjuster. I gave it a ultra sonic bath with pinesol .... it works as well and smells fresh. Just discolors the brass. What a pain in the arse! has to be the most complicated MC carb I've seen. Did you buy the gaskets separate? I didn't realize or check mine. It has a hanging idle. I figured its the adjustment screw issue, but if that doesn't work may try to find the gaskets. Thanks for vid....

I have a suzuki rmz 450 2007. It was sitting about 1 year.. it did not start.. cleaned the carb twice.. it started but it is running well only with choke on.. when the choke is off the bike popping and backfiring... Also a little smoke comes out from the carb... What is going on????