Yamaha XJ650 Part 20 Carburetor Rebuild

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The carbies are now all back together and ready for final install. I've used a 6Sigma Jet Kit.
Here's a link to their site should you want to purchase a kit for your own bike.
www.6sigmajetkit.com/

[@peterperry3918]

There are four points that in my opinion make this the best carb video I have come across: 1: very comprehensive, 2: clear verbal description, 3: good camera/visual coverage, and most importantly 4: accurate information. Well done, I will be looking forward to future videos.

[@Mezzmoengineering]

Thanks Peter, I appreciate the feedback

[@thenoob2330]

i just bought a 82 maxim 650 and the previous owner disassembled the carbs so now i got to figure out how to re assemble them,. thanks for the video mate. !! it gona help out a ton.

[@jeanfrancois8974]

Many thanks for your splendid videos and work on your bike. You saved my life and my yam too. Kiss from France

[@Mezzmoengineering]

Great to hear!

[@jasoncraig9633]

Excellent fully encompassing video with great angles to see everything clearly. There are so many other posts that only do jets or butterflies, etc but you did everything! Thanks so much!!

[@Mezzmoengineering]

Thanks mate, happy to do what I can to help others

[@MattysWorkshop]

Gday, one of the best videos I’ve seen in a while, very straight forward and no B/S, thank you,

[@Mezzmoengineering]

Thanks Matty

[@glennvonk719]

Great video. I've watched a bunch of XJ carb rebuild video recently as I am deep cleaning my 550 Seca carbs and I have to say your instruction is top notch!

[@clickireland1113]

Great camera work. A lot of works videos can get posted 'assuming' the viewer knows whats been done, and camera angles in these do not show whats being described. You did a great job actually showing the procedures you were talking about. Looking forward to doing a rebuild on my 1980 XJ650. Currently stripped to the frame and I'm making a blasting cabinet. Must buy a good screwdriver set. Thanks a mil

[@Mezzmoengineering]

Thanks mate, I'll do a similar video when I rebuild my engine

[@clickireland1113]

@@Mezzmoengineering Very welcome. Be glad of the engine video coming. I busted a piece of the lower crankcase taking a mount bolt out. Do you want a good second-hand sledge hammer?

[@Mezzmoengineering]

@@clickireland1113 I have purchased a newer head but it has some broken fins. I'll aim to do a video on welding them up. Don't really use a sledge hammer to often, I prefer the tools to do the work instead of me...

[@clickireland1113]

​@@Mezzmoengineering You'd know more than me about this link but I think its worth a look. Al welding: kzbin.info/www/bejne/l5uTf52td9amick

[@Mezzmoengineering]

@@clickireland1113 Thanks for the info. First I'm going to try TIG welding these fins on an old head I have. It that doesn't work I'll give these a go

[@johnpaulmakowski7464]

Excellent informative and detailed. Nice and close camera. This will definitely help me in my first carb rebuild of my 1981 yamaha maxim.

[@Mezzmoengineering]

Thanks for watching!

[@Richard-lionhearted]

Awesome ! With video 17 makes for a perfect set to learn from ! Thanks So Much ! ! !

[@Mezzmoengineering]

Glad you liked it!

[@jh-tech5546]

Great explanation and nice tip for the alignment of the carbs!

[@Mezzmoengineering]

Thanks mate

[@jorgefonseca9225]

This guy is a really fucking good 👍👏 you understand really about carborator's 🤔👏👏 I do like do on my XJ900 cheers from Norway 👋

[@Mezzmoengineering]

Thanks mate

[@chrismelnyk1351]

Thank you for this video. It has been an excellent reference for my xj 650 carbs.

[@Mezzmoengineering]

Hi Chris, thanks for the feedback. Glad its helped you.

[@ewademail]

Thank you for the inspiration to complete one of my projects. Cheers

[@Mezzmoengineering]

Thanks Ethan, glad its helped you

[@domalbe51882]

Very very helpful, keep up the good job, stay safe...

[@zoomzoom8704]

Thank you for such a clear video, I picked up an xj650 Maxim. The carbs came in a Walmart bag completely disassembled. I was going to lose my mind trying to figure out how to put it all back together and which Jets went where.

[@Mezzmoengineering]

Good to hear it helped you out 👍

[@shawnmrfixitlee6478]

great job , going to run like a treat !

[@Mezzmoengineering]

Hope so, looking good so far

[@armandosairally]

Just watched all ...Great job 👏

[@Mezzmoengineering]

Thanks mate, glad you enjoyed it!

[@seanboxer1521]

Thanks for this. Best videos out there.

[@Mezzmoengineering]

Thanks mate

[@rico1dennie704]

Nice Job

[@Mezzmoengineering]

Thanks!

[@fixitnowmowers8065]

Howdy! Very informative video! I however have _just_ noticed at 6:56, not a one of my 4 carbs have this plate! ( nor attaching screw).

[@Mezzmoengineering]

Hi mate, it your carby has the bolt hole but it doesn't have an internal thread then you have the version where the plate was removed. The later models didn't have that plate so nothing to worry about.

[@Mudmowerdiesel]

Awesome video thank you

[@Mezzmoengineering]

Thanks for watching

[@thedge7]

Nice to see some competent content! lot of hacks out there...

[@Mezzmoengineering]

Thanks mate

[@jimmyguenza3767]

Another great video from the Master Craftsman ! Where did you get all that knowledge and patience man ? Keep up the good brother. And thank you ! Jammin Jimmy

[@Mezzmoengineering]

Thanks Jimmy. My knowledge started from being a Fitter and Turner for a few years, then studying Mech Eng and being an engineer for a long time and always tinkering in the shed to keep my practical skills. And by not being scared to try new things and push the boundaries. Not sure about my patience, I just have got to a point where I really understand metal, mechanics etc.

[@stevec-b6214]

good stuff buddy - starting on mine tomorrow - treated myself to an ultrasonic cleaner (told the wife I could clean her jewellry with it) note to self - buy wife some cheap jewellry ;)

[@Mezzmoengineering]

Thanks mate, an air compressor and cheap sand blaster is great too. The wife will love you cleaning the old garden ornaments with it.

[@emilioguitart3754]

Wow !! Awesome work!! Best carb clean tutorial since internet born! Is there any link for the shaft seals!!

[@Mezzmoengineering]

Hi mate, I got the seals on eBay. If no luck, look up XJ forums and find a guy called Chacal. He has most parts for sale

[@esoteric_Derek]

tre magnifique!! 🤗 ¡Sois magníficos! 👐 The prestigious academic videographic zenith! 💪😎👌 #zenandtheart

[@Mezzmoengineering]

Thankyou!

[@ursamajor339]

This video is AWESOME! This will be my first carb rebuild and this will make it so much easier... One question, and maybe it was already said, but where can I find the T fuel pipe O rings to purchase? As well as the V O rings? Thanks so much again!

[@Mezzmoengineering]

Hi Mate, I found the V rings on ebay and the tube O-rings I bought genuine from my local dealer. V-rings are expensive, but worth it imo. Here's a link to the v rings, www.ebay.com.au/itm/XJ-650-V-RING-WELLE-DROSSELKLAPPE-DICHTRING-SIMMERRING-12x8x2-YAMAHA-VERGASER/383034390789?hash=item592ea0f905:g:rhQAAOSwv1RUZ4FN&frcectupt=true

[@danmeifert2469]

Another option for parts is on xjbikes.com where I got parts for my first multi card rebuild. Keep parts organized & take pictures. Mine were apart longer than expected. These videos helped, thanks.

[@alexgorgon8025]

Супер! хорошая работа!!!

[@Mezzmoengineering]

Thanks mate!

[@bestione761]

Hi again! After having done the valve clearance, the carburators cleaned (sandblasted and ultrasonic), the jets changed and needle, changed also the throttle shaft seals (v-rings ), fuel pipes o-rings (Yamaha) and so on... everything looks like new. I have syncronize the carburetors using the YICS tool with two sync gauges, one with just one clock and one with 4 mercury lines to see if the four carburators go up at the same time. Well the idle is driving me crazy, I used the colortune in each spark to search for a bunsen blue colour but it is not that easy... I started the pilot screw settings at 2,5 turns out but the idle goes up to 3000 rpm and when I screw out the idle screw the engine stops. If I srew the idle screw in just a bit.... the idle goes up again to 2500-3000 rpm... and if I change the ratio of the pilot screw it keeps doing the same. Any Idea?

[@Mezzmoengineering]

Hi Marcos, this is very odd. Its hard to identify the problem without seeing it but a couple of things to check are - did you fit the V rings the right way around? The V needs to point outwards as carbs are just about always under vacuum. Did you replace the rubber boots, there could be an air leak there. Sounds like you have air getting in somewhere, my guess is its the throttle shafts...The mixture screw should not change things with minor adjustments

[@bestione761]

@@Mezzmoengineering V-rings where fited the right way and also new rubber boots where fited. I will keep trying to play with the pilot screws.

[@robzrrr]

@@bestione761 Did you get this problem sorted as i have the same on mine after rebuild, idle is too high at 2000rpm with the idle screw fully out

[@bestione761]

@@robzrrr Hi there, I gave up and took the bike to a workshop. Now I am waiting the result. I hope they are going to be able to play with the pilot screws and the butterfly shaft screws with more luck than I did it. Will let you know.

[@narajuna]

Looks well done, but I have a idle adjuster that is not working and the bikes runs only at high revs, guess something is stuck in there :(

[@Mezzmoengineering]

Hi Mate, it could be a number of problems. Best thing is to pull them apart, clean very thoroughly and then reassemble and check everything works right. Also high revving could be choked not sealing, slides sticking or wrong size jets

[@narajuna]

@@Mezzmoengineering Well it wont start with choke anymore.

[@robzrrr]

@@narajuna Did you get this problem sorted as i have the same on mine after rebuild, idle is too high at 2000rpm with the idle screw fully out

[@bestione761]

Hi there again! I am still fighting with my carbs 😞. After having rebuild the carbs, and having done valve clearance, sync the carbs etc...the bike still has a high idle and it won't get down as fast as it should, but now I found something interesting... maybe you can help me out. If I turn out the idle screw, let's say almost all the way back the engine stops, which is normal, if I don't use the throttle. If I screw the idle screw in just a bit, the engine starts to increase the rpm up to 3000, at that moment I have to unscrew the idle again out to low the rpm. Now , if I low the rpm the engine stops but if I use the throttle to acelerate the engine, the rpm go up and down smoothly as it should.... but if I don't use the throttle when I stop, the engine dies again. This means that either I have a good idle speed and let the engine die unless I play with the throttle or I have high rpm, bad idle speed and the engine does not die. Of course I prefer the first scenario. But what I don't understand is that if I keep acelerating the bike with the throttle just a bit the rpm stay on 1000 and if I screw the idle screw just a bit, what should do the same job, the engine rise the rpm up to 3000 and won't get down fast as it should and sometimes staying at 3000 rpm. I have been told already that it must be air coming in, but everything in the carbs is new and quality replacements. Any Idea what could be happening? This is driving me crazy, asking motorbike shops they don't like to touch this kind of old motorbikes. What can I do? 😞😓😩 Thanks mate

[@Mezzmoengineering]

Hi, it does sound like air getting it. Have you checked there are no holes in any of the diaphragms? Try carefully spraying engine starter around places where air could be getting in while the engine is running. The engine RPM will increase if the spray gets sucked in somewhere

[@robzrrr]

Great video thanks.Fully rebuilt mine exactly as you have done, with new intake stubs also - but now the idle will will not go less than 2000rpm with the idle screw fully out, odd.

[@Mezzmoengineering]

Hi Mate, sounds like air might be getting in somewhere. Have you replaced the v-rings and if so are they in the right way around. You also need to be sure to sync the carbs and set the fuel levels. Other thing it could be is the choke needles not seating properly. Try push them down when running to see if idle reduces.

[@robzrrr]

@@Mezzmoengineering Corrected the problem , I had the air jets under the diaphragm round the wrong way ! Thanks for your video that confirmed the correct way as the Yamaha manual has a mistake in one of the pages showing them the wrong way .

[@Mezzmoengineering]

@@robzrrr Good one, glad my video helped you out

[@jeremyubrien2955]

Great video. Fully detailed as usual. I am part way through rebuilding my XJ750 carbs and following along has been great. However, I have noticied that my carbs 1 & 2 are different to 3 & 4. Perhaps the previous owner had to swap them for some reason. Carbs 1 & 2 don't have the plate over the 2 air jets and you can't fit one because there is no thread for the securing screw. Also, the tiny ports for the choke in the bowl of carbs 1 & 2 are blocked and no matter how much I try to clear them with mig wire etc I can't clear it. Coincidence? Do you have any spare carbs from your XJ750 for sale? Do you know who is the guru with these carbs? Looking forward to the new workshop videos.

[@Mezzmoengineering]

Hi Mate, I need to see what I might have to sell. Remember the hole for the choke is very small, smaller than MIG wire. Try pulling out one wire from a wire brush as thats more like the size. Yes, the plate you refer too and on some XJ's and not others. Can't remember if its was an early model item or late model but I;m not sure you can mix them.

[@jeremyubrien2955]

@@Mezzmoengineering Thanks for getting back. I got the tiny ports opened up by rubbing down the mig wire. The other problem still remains of course. I have spoken to a local (older) Ex Yamaha mechanic who thought it would be unlikely that someone would have swapped out just 2 carbs. It did run (rough) when I first got it. Will just have to give it a go I guess but I am still interest in any spares should things not go to plan!

[@kyleweber9142]

I need some help love your videos can I use an xj750 carb rebuild kit on xj650 carbs? I cant find kits for the xj650

[@Mezzmoengineering]

Hi Mate, XJ750 carbs are the same bodies as XJ650. Only difference is the needle and jet sizes. All seals, gaskets, floats etc are identical

[@user-yf5wx6hp7r]

Does the plate in the middle of the carbs over the air jets that's underneath the needle system need to be on one of them?

[@Mezzmoengineering]

Hi mate, the early version has plates, one on each carby and the newer version does not have the plates. The newer ones still have the bolt hole but there is no thread in there, hope that helps

[@randysrestoration]

1982 Yamaha shop manual shows those pilot/main jets going opposite positions (under diaphragm) 6:42

[@Mezzmoengineering]

Hi mate, interesting. I plan to pull the carbs out soon to make a small change to the pilot jets. Will check this to confirm if I either made a mistake or just said the wrong thing...

[@randysrestoration]

@@Mezzmoengineering have mine apart now. Can’t seem to get it to run right. Found idle mixture screws all over the place from 2 3/8 turns to 3/8 turn. At least i have carb pull down to under 15 min!

[@Mezzmoengineering]

@@randysrestoration Yeah, it can be tricky. The main thing is to be sure its all very clean. If you haven't done mods its a matter of being methodical and thorough. If you have lots of mods like me then it can take a lot of tuning. You should use the syncing tools to be sure all carbs are balanced. I also used the "color tune" to get the idle mixture right

[@randysrestoration]

@@Mezzmoengineering i did buy the Yamaha YICS tool found new one in package online. Will need the 4 gauge setup as typical vacuum gauge will not work. It has 165 psi compression and valve lash is spot on. Zero mods of any kind. Still Yamaha air filter. Found NOS boots engine side and airbox side. Unreal nice unrestored bike although did paint tank and side covers. Trying idle mixture to see what it does. 1 out 3/8 turn suspicious. Carbs look new inside. Carbs n tank were dry when parked 30+ yrs ago.

[@randysrestoration]

I cleaned carbs 30+ yrs ago but bike never ridden since then.

[@Aciecarter238]

What size is the air jet on front of carb. I have a 80 an a 36 on my xj 750. Rebuilt it annlosst my paper diagram for everything. Does the 80 go on left an 36 go on right side

[@Mezzmoengineering]

The air jets were the only things I didn't remove. Check this link as it should have what you need, xjbikes.wikidot.com/carb-specs

[@marcfitzgerald6437]

Hi. I have a 82' XJ550. I need to replace the o rings on the carb connectors. I can't find what size I need. Any help would be helpful. Thanks

[@Mezzmoengineering]

I'm not sure of the exact size as I just went to my local Yamaha dealer and purchased them brand new

[@bestione761]

Hi there! Thanks to your help again mate! Now I have another issue, with carb nr. 3, once I put the throtlle shaft in, the v- rings and spring everything seems to be fine but when I put the butterfly on the throtlle shaft, it get stucks. I tried many times and it gets stuck eveyttime. I marked the butterfly as you do when I took it apart and I know for sure I am putting it back in the same way as it came out. Throtlle shaft does ' t have any play and as I said, everythings works fine but the butterfly keeps getting stucked everytime I tried. I am doing everithing with a lot of care and very gently... Any Idea what am I doing wrong? Thanks!

[@Mezzmoengineering]

Hi Marcos, something is not right. You might have the butterfly in the right carby but are you sure you have it the right way around? Look very close and you will see the butterfly has a tapered edge and will only fit properly one way. It will fit the other way too but will cause a problem like you have. Also if the butterfly is correct you might need to adjust the position. First keep the two holding bolts a bit loose so it can move, open and close a few times so it seats properly and then tighten. Either its the wrong way around or needs position changed slightly within the slots in the butterfly. Let me know what you find...

[@bestione761]

@@Mezzmoengineering Hi mate! Finally I resolved the problem. I was trying to put the butterfly... let's say sliding the butterfly once I turned the throtlle shaft, from the bottom to the top and today I tryed from the top to the bottom where it is suppossed to fit. It's my first time doing this job and that's why I am getting stuck in obvius things. Yesterterday one of the butterfly screws broke down inside the shaft... I almost had a heart attack!!! I had to drill again a hole and give it a new thread, Lucky me!!! Everything worked fine. Thanks again for your help.

[@Mezzmoengineering]

@@bestione761 Good work!

[@mechman4]

Awsome video ! Considering this mod on my bike. Just wondering if you have the Yamaha part number on those v rings ?

[@Mezzmoengineering]

Search on ebay for XJ650 V-ring

[@mechman4]

@@Mezzmoengineering Very expensive little v rings. Do you think o rings would work ? Or would that just be asking for trouble to occur ?

[@Mezzmoengineering]

@@mechman4 O-rings will work but probably wont have the same longevity. If you want reliability I'd use V-rings. If you ride occasionally then o-rings will last a while.

[@johan9093]

Great video. Im trying to fix a xj 650 myself. Do you happen to remember where you got the v-rings? Im having trouble finding any.

[@Mezzmoengineering]

Hi Mate, Yes I got them on ebay. Just do a search for XJ650 V Rings, there are not cheap but worth it....

[@johan9093]

@@Mezzmoengineering Thanks mate. Appreciate it.

[@borjatranche8846]

I’m rebuilding the same carburetors and I have a problem. Where do you bought the no cheaps V-rings of min 5 in the video? I’m from Spain and I can’t find them. Thanks. Great video and nice job.

[@Mezzmoengineering]

Check this link, www.ebay.com.au/itm/2x-CARBURETOR-THROTTLE-BUTTERFLY-VALVE-SHAFT-SEAL-12x8x2-XJ550-XJ650-XJ900-XJ750/254570907087?hash=item3b459bc5cf:g:rhQAAOSwv1RUZ4FN&frcectupt=true

[@borjatranche8846]

Thanks!! Muchas gracias!

[@bestione761]

@@borjatranche8846 Hola, estoy en las mismas que tú ¿conseguiste los v-ring y o-ring? En el enlace de eBay solo vende 2 v-ring sueltos y quería cambiar los 8 que llevan los carburadores. Gracias de antemano

[@joerosenberger7102]

Is the plate over the air jets necessary? Can’t seem to find a rebuild kit that has this part

[@Mezzmoengineering]

Hi mate, I don’t really know what that plate does. In fact that plate seems to be on earlier models and is not there on later models so maybe it’s not required.

[@kenw3776]

I’m building a xj750 right now would this be the same jet set I would need to convert to AirPod filters????

[@Mezzmoengineering]

Hi Mate, I don't think so as I also did other mods. Eg Bigger exhaust, slight porting and capacity increase to 820cc

[@cowtippingrocks]

I have a question about the air jet cover plate shown at 7:00 . I recently was given an 83 XJ650 that was dead. All 4 carbs on my bike are missing that plate and screw. Could this be what is causing the throttle to go wide open when I start it? I have already made sure that the throttle and choke cables are set up properly.

[@Mezzmoengineering]

I doubt that’s the problem. Sounds like you might have air getting sucked in somewhere, maybe a damaged rubber boot

[@cowtippingrocks]

@@Mezzmoengineering Thanks. I'll have a better look. The boots are original but don't look too bad. Maybe they aren't on property.

[@The.reel.yak.dragger]

At the 12:24 mark you are showing the intake side of the carburetor. What are those jets called? I have an XJ650 that is missing one and I cant seem to find that in any schematics that I've looked at.

[@Mezzmoengineering]

the two jets on the front are the air jets

[@The.reel.yak.dragger]

Mezzmo Engineering what jets though? I can’t even find them in the schematics. Any way you can find a part number?

[@Mezzmoengineering]

@@The.reel.yak.dragger Check this link, xjbikes.com/forums/threads/in-the-church-of-clean.14692/ there's a lot of info there including link to parts

[@milanmarko1771]

Hey Mate. Awesome video. I am building a cafe out of an XJ650. Do you know where do I have to connect the vacuum line by any chance?

[@Mezzmoengineering]

Hi Milan. The vacuum line goes to the fuel tap. Take your pick to which carby you connect too. It doesn't matter as long as its connected to one carby. The others are blanked off.

[@milanmarko1771]

@@Mezzmoengineering I know one end goes to the petcock wasn't sure where the other end needs to be connected. It is between the carbs and the engine on the rubber boots right?

[@Mezzmoengineering]

@@milanmarko1771 You connect it to the barb on one of the rubber boots

[@jonathanrogers9943]

Hello, do you have the part number for the v-rings? I’m rebuilding the secs turbo carbs.

[@Mezzmoengineering]

Hi Mate, there are not cheap but I got them from ebay, check this link www.ebay.com.au/itm/254824644963?hash=item3b54bb8163:g:rhQAAOSwv1RUZ4FN&frcectupt=true

[@TheSteveniell]

Hi professor (Cause I’ve learned a lot from your videos), please help me. I finished the electrical and rebuild the Carbs but missed the detail about upgrading the main jet or air jet idk. Since I’m not using the air box it’s sucking much air so I need to compensate with gas. My question is, is only the main jet from #110 to #130 or also other jets that needs to be upgraded? TIA 🙏🏼

[@Mezzmoengineering]

Hi mate, Its difficult to say for sure, but my guess is you should have a pilot jet of around #40 and main jet should be #120 or #125. The air jet should be ok as it is. This should be close but you need to tune to get it right. Good luck...

[@TheSteveniell]

@@Mezzmoengineering as always thanks for taking your time to respond professor, so, after I wrote you that message earlier I kept watching your videos as always ausencia like every time I watch it I discover something new. So I went I ordered the kit from 6Sigma. Gave them the info they needed to customize it and I should get it in a couple days. Thanks so much for your inspiration.

[@Mezzmoengineering]

@@TheSteveniell No worries, sounds like a plan. Let me know how you go...

[@Disembodied]

10:06 you spray a little bit of what? Sorry I couldnt understand and want to make sure i got it right

[@Mezzmoengineering]

Hi mate, its an aussie lubricant spray called "INOX". Any similar lubricating spray will do the trick

[@pethelprc4721]

hey bro when running washers on your needle did you leave the little nub inside the slide that forces the needle to tilt or did you take it off so the needle hangs straight?

[@Mezzmoengineering]

Hi Mate, just added washers to the stock set up. The needle is held straight once installed so all good

[@pethelprc4721]

@@Mezzmoengineering i went back and watched that part of your video a couple more times in slow motion and saw that your needle was still cocked at an angle with the washers, that's why you had to reach in and guide the needle into the nozzle. i can't find anyone who knows why hitachi made it so the needles are cocked off at an angle, never seen another carb that was like that, guess i'll just deal with it..thanks for responding....

[@glennvonk719]

An old comment but I just delt with this issue today. The little nub on the rubber ring that is toward the top of the jet needle fits into a little hole at the bottom of the slide. When installed correctly the needle will be straight.

[@hermilogonzalezlara5894]

Hello, good job, I have a question, what is it called and where do I get the piece that you have at minute 6:57?

[@Mezzmoengineering]

Hi mate, if you mean those small plates then I'm not sure you can get those by themselves. Remember that some models of XJ650 and 750 didn't have these. If there's a thread for the bolt then you probably need them, if its just a hole with no thread then maybe yours never had them to start with

[@mechanic5069]

Hi can you tell what's the paint name you used to paint carbs top covers? Black textured? Feedback appreciated. Very good job by the way.

[@Mezzmoengineering]

Hi mate, I show the can at the beginning of the video...High temp wrinkle plus

[@mechanic5069]

@@Mezzmoengineering many thanks for prompt reply 👍🏻

[@bikerscops1816]

*_Hello, I'm French and I'm also restoring a 1981 model, why do you pierce the bushel with the membrane? and which drill used you No. 2 or 3?😉✌_*

[@Mezzmoengineering]

Hi, this is a mod to adjust the fuel ratio to suit my engine modifications. Eg Big bores, bigger exhaust, K&N filter pods etc. I have have bigger jets to get the mixture right

[@bikerscops1816]

@@Mezzmoengineering Okay, but I can do it even if I keep the same cylinder, it won't cause a problem?

[@Mezzmoengineering]

@@bikerscops1816 Hi Mate, check my video again and find the link to 6Sigma. They can sell you a specific carby kit for your engine and will confirm if you need to drill a hole or not for your actual set up. I've used them on this engine as well as my Mowzuki and both times its been great. Lots of people will tell you not to use pod filters but from my experience they can work fine if tuned properly.

[@Mezzmoengineering]

@@bikerscops1816 Hi Mate, check my video again and find the link to 6Sigma. They can sell you a specific carby kit for your engine and will confirm if you need to drill a hole or not for your actual set up. I've used them on this engine as well as my Mowzuki and both times its been great. Lots of people will tell you not to use pod filters but from my experience they can work fine if tuned properly.

[@bikerscops1816]

@ *_ok thank✌_* Mezzmo Engineering

[@inder605]

Can anyone recommend a quality carb rebuild kit for this carburetor

[@Mezzmoengineering]

Hi, the kits are pretty basic. I think you should be able to find something easy on ebay. Its just a gasket, 2 jets and o-ring for the mixture. The main thing is to ensure you clean them properly..

[@daleirvine4110]

hi mate, what size are the o rings for the carburetor connectors

[@Mezzmoengineering]

They are an odd size so I just purchased new from my local Yamaha dealer

[@pethelprc9585]

a 45 pilot, what kind of mods do you have to need a pilot that big and what altitude are you at?

[@Mezzmoengineering]

Altitude around 300m, mods are big bore and stroke to take it to 820cc, lightly ported, custom open exhaust and K&N filters. Haven't started it yet so time will tell if its right

[@oscarperezgonzalez9203]

Hi thanks for the part number do you know the part number or where I can find throttle shaft seal and how many do I need and also the choke shaft seals and how many do I need this also your videos have been really helpful thanks for your helpfull

[@Mezzmoengineering]

Hi mate, use this link. www.cmsnl.com/yamaha-xj650_model16829/ Everything you need is there, you can also order through that site for genuine parts,

[@oscarperezgonzalez9203]

Hi thank you for your reply I found the choke shaft seal but I can’t seem to find the throttle shaft seal can you help me identify it in the diagram thanks

[@Mezzmoengineering]

@@oscarperezgonzalez9203 You're right, they don't list them. I found mine on ebay. I checked now but can't see them for sale anymore. I'm not sure on the part number. If you get stuck join the XJ Forum page and find a guy called Chacal as he will be able to get them for you,

[@oscarperezgonzalez9203]

@@Mezzmoengineering thanks I’ll be looking around to see if I find it my bike is a 1982 xj750r seca I don’t know if the 650 are different

[@Mezzmoengineering]

The seals for the carby are the same for both xj650 and xj750. Xj750 just has different needle and jet sizes.

[@stephanelessard4570]

What is the solution for cleaning the washer? Water with somethings else as soda bicarbonate? thanks for your advice

[@Mezzmoengineering]

Hi mate, no the washers are just quenched in water. To anneal copper it needs to be red hot and then cooled rapidly so all you need is water straight from your tap, no additives needed

[@stephanelessard4570]

@@Mezzmoengineering thanks for your return quickly. Another question for you: what is the level about float? i rebuilt carb Maxim 750 1982 and some people says adjust to17mm and another say another thing. i adjust those mines at 16mm and seem ok but not istall yet in the machine. Can you tell me what is the good level? Thanks

[@Mezzmoengineering]

Check this link for the proper fuel level, kzbin.info/www/bejne/n5XdaaNmd82Ngrcsi=6KKmODrBFp_RCspW

[@mousey2185]

I’m not sure why I thought I was one of a few people who heated copper rings up to clean them. Idk I just didn’t think people did it.

[@Mezzmoengineering]

Hi Jamyil, heating copper cleans it but the biggest benefit is the annealing which makes them like new.

[@maxroll7360]

Can you tell me where the carb drain screws are located?

[@Mezzmoengineering]

Hi Max, sure, its the screw in the base of the carby bowl, one one each carby. The screw is one the side so it can be accessed on the bike for carby 1 and 4

[@nestorgonzalez1775]

Hi Im Nestor from Guatemala, I have a question I got a Yamaha maxim and the carburator its wrong if I send you can you fix it? Sorry if my english its not so good

[@Mezzmoengineering]

Hi Nestor, at this stage I'm working on getting a new workshop set up. Once I have that sorted I will offer my services for this type of work. The only problem is that I will not be able to do outside work until later this year

[@nestorgonzalez1775]

@@Mezzmoengineering ok, If I understood well you mean that you cannot work outside of your country Your not able to do it outside ?

[@Mezzmoengineering]

@@nestorgonzalez1775 Hi Mate, no I can do work for anyone. Its just that I'm not set up with a good workshop just yet. I'm planning one now. I hope by the end of this year I will have it built and I can then have time to offer my services globally.

[@clannishkobra8965]

Where did you find the v band seals

[@Mezzmoengineering]

Hi Alex, I found them on ebay. Check this link, www.ebay.com.au/itm/2x-CARBURETOR-THROTTLE-BUTTERFLY-VALVE-SHAFT-SEAL-12x8x2-XJ550-XJ650-XJ900-XJ750/254570907087?hash=item3b459bc5cf:g:rhQAAOSwv1RUZ4FN

[@marlon45aries20]

hello I don't understand why you made two holes with the drill I have a yamaha xj 700 from 85 clean the carburettors the part that you made holes mine has two a big one and a smaller one the question which of the holes go next to where the air filter enters the largest or the smallest hole I did not realize that when I removed it and I do not know how to leave it now

[@Mezzmoengineering]

Hi, the tab on your diaphragms will confirm the rotation. Drilling the holes out is a mod to allow the slides to close quicker and stop lean out problems. This is sometimes done when bigger jets and other mods are done

[@marlon45aries20]

@@Mezzmoengineering thanks....

[@Gortello]

where did you get those v-rings, cant find the oem number or a seller but mine are definitely done

[@Mezzmoengineering]

Hi mate, I found them on ebay, if no luck try going to the XJ Forums, a guy by the name of Chacal has all the parts you might need

[@Gortello]

@@Mezzmoengineering do you have the OEM number by any chance ? that would make searching a lot easier

[@Mezzmoengineering]

@@Gortello check this link, www.cmsnl.com/yamaha-xj650_model16829/?psafe_param=1&gclid=EAIaIQobChMI0I3O457Q_gIVOZpmAh1i_gVrEAAYASAAEgKWePD_BwE

[@jordanstepp183]

Will this rebuild be identical for the xj750?

[@Mezzmoengineering]

Hi Jordan, Yep, XJ750 is the same. There are only very minor differences being with the needle profile and jet size. Other than that its the same

[@trentgullett8538]

Where did you find the V rings?

[@Mezzmoengineering]

Hi Trent, got them on ebay,. check this link www.ebay.com.au/itm/254824644963?hash=item3b54bb8163:g:rhQAAOSwv1RUZ4FN&frcectupt=true

[@thehutx]

hi were did you buy the v ring seals

[@Mezzmoengineering]

Hi mate, I got them on ebay. If you can't find them go to the XJ Forums online, join up and then see Chacal as he sells a lot of gear.

[@thehutx]

@@Mezzmoengineering cheers m8t

[@oscarperezgonzalez9203]

How many o rings does it have on the tubes to connect all the carbs together and do you have the part number

[@Mezzmoengineering]

I think its 6 total, check this link for all the part numbers

[@oscarperezgonzalez9203]

I checked is just jet kits I can’t find them

[@Mezzmoengineering]

@@oscarperezgonzalez9203 The o ring number should be 3J31414700

[@oscarperezgonzalez9203]

@@Mezzmoengineering thanks you so much iam gonna subscribe to your channel

[@koma4953]

Hey @Mezzmoengineering great job what you done with XJ650... I am also doing mine but can you pls help me and send me link or part number of V Oring? I can't find anywhere :( Thanks

[@Mezzmoengineering]

Hi mate, I got them on ebay but they don't seem to be there now. Go to XJ Forums online and find a guy called Chacal, he sells all parts you need

[@sandracarter15]

Im attempting this and cant find the rest of the videos! Im an internet idiot! Any direction would be greatly appreciated

[@Mezzmoengineering]

Hi, check this link to see all my videos listed, kzbin.info/door/6FlCl6Yi-Lq_2ykmDmmgtQvideos Or if you want it by playlist try this one, kzbin.info/door/6FlCl6Yi-Lq_2ykmDmmgtQplaylists Hope this helps.

[@manii8597]

I would like to see if you could help me, I am from Mexico, I got a problem with a Yamaha yics 750 engine, it the bike doest have any of the electronics on it, so when I get the battery to start up the engine it cranks up, it makes the sound like it wants to start but and the end it doesn't, I tried taking the bike with a macanic, but he was not really good, he told me a problem it had, I gave him the money, but he ended up not doing anything to the bike, he returned it the same way, and after 2 weeks he said he didn't know what was wrong with it, but still charged "for the time" Another mechanic told me that I had to change all the carburators, the engine rotates when I take the cover off but I still can't make it start up

[@Mezzmoengineering]

Hi Manuel, OK, so was the engine running before? Have you changed something? First you need to check the basics, Eg for the engine to run its needs to have a spark, fuel, air and compression. So do a compression check, it should be around 150PSI but will still run as low as around 90psi. Then crank the engine with a spark plug removed, earth the plug to see if there is spark when cranking. Fuel check is easy, just use some engine starter spray, spray into carby inlet and if the problem is fuel it will run for a few seconds properly and then stall. If there is a spark and fuel is good and it won't start it could be bad timing. First check these basics.

[@manii8597]

@@Mezzmoengineering thx for answering the question bro,I was lucky I returned the bike because something with the paperwork on it was wrong, and changed it for a 1995 Kawasaki Vulcan 750, I just need a tutorial on how the clean the carburators, the previous owner was kind enough to show me the bike running on borrowed ones, and told me the originals from the bike where dirty, with a good clean up, and giving the bike some love it should work perfectly, he also told me they need a very good clean up because the bike had been sitting still since two years ago. But I do appreciate you answering me, keep forward to seeing more tutorials about engine repairs or clean ups 👍 if you happen to do a Vulcan let me know so I can look at it and also do mine.

[@VileMinister666]

What's the part # for the full assembly?

[@Mezzmoengineering]

Sorry, I don't know. If you find it post it as it might help someone else...

[@jakeman4325]

I are these the same as the xj550??

[@Mezzmoengineering]

Hi,, not sure if they are physically the same but jet sizes etc will be different. I wouldn't recommend putting them into a 650

[@isaig.9222]

6:44 what size jet is this? and the one to the left also

[@Mezzmoengineering]

Its 225 air jet

[@isaig.9222]

@@Mezzmoengineering 225? I found the answer from someone else but they said 50..

[@isaig.9222]

@@Mezzmoengineering Regardless thank you

[@Mezzmoengineering]

@@isaig.9222 Hi mate, no its not 50. This is the pilot air jet which is definitely 225. The main air jet is 80. Put a 50 there and it will be running very rich or probably wont run at all. If you are in further doubt I'd suggest buying a manual as its all in there. Also for interest jet are measured in mm, Eg a 50 is equal to 0.5mm and a 225 is 2.25mm. You can see from my video that the hole is much bigger than 0.5mm

[@isaig.9222]

@@Mezzmoengineering So does a #50 air jet go anywhere? I have the exact carb or so I believe off a 81 yamaha xj650 except if its 225 then where did these go? I did take pics but its not adding up. I cant get anywhere without knowing what size to put in

[@jmmoto897]

Would you redo my carbs I’ll send you them and money

[@Mezzmoengineering]

What is the problem with them?