1. Kutay

    Problem installing air intake rubbers

    Hello, I am working on ym XS400 just like a lot people here. I already rebuilt the mechanical parts twice, it was a dead bike and I am trying to revive it. It is now running, whoop whoop. I am stuck on a small maybe funny problem. I cant get the rubber parts that connect the carburetor to the...
  2. YooperGoat

    New XS, looking for build/maintenance guidance

    Hello, new member I acquired a 1981 XS400H (I believe) and will have access to the bike later this summer when I return home. I am learning as much as possible before then. I have an idea of what needs to be done to get it running. As well as a list of questions Firstly, I plan on stripping...
  3. E

    Fuel tank removal to access carburetors for cleaning

    Hey, new to the site but I have a 1982 xs400 YICS model and need to clean the carburetors and need to remove the fuel tank first. I am VERY new to this so I am learning as I go and wanted to ask those with more experience on the topic. I've looked at videos on how to remove the fuel tank with...
  4. S

    Engine Temps

    So I got everything running good but I just want to know what you think is a high engine temp and if the spark plugs look lean. After riding the bike for 20min and giving it some juice, the spark plug sensor is reading about 310 when its 88F degrees. Using a laser temp I was getting about 290...
  5. J

    Is my carb ruined? :/

    Hi dudesters, so im thinking about getting this old bike running, and got around to doing the carbs after a short span of inactivity (the thing has been dismantled for 7 years give or take). So to my surprise i found both idle jets were jammed in too far, subsecuently got stuck and the tips of...
  6. JStaggs99

    Will I need to get new carbs?

    Howdy, first time posting and just got an 81 XS400 yesterday. Now I'll preface this by saying I'm not a bike mechanic by qny means but I am an auto mechanic. The guy said the carbs had a float issue and they absolutely do. The floats have holes in them so they'll need to be replaced for sure...
  7. X

    '77 XS400D - Choppy Idle / Ticking noise

    Hello everyone! I've got a 1977 XS400D with 19000 km on it (or so my speedometer says) the bike and engine is in great condition visually, carbs are in great condition as well. Im the first one to register this bike in Canada so theres literally no record of it prior to May 2021. When I...
  8. Joost D

    fuel leaking through carburetor

    When the engine is running or when the petcock is on prime, the gasoline drips from the back of the carb. It seems to be coming from the 2 jets. All rubbers and gaskets have already been replaced. Does anyone have experience with this? In the link is a gif where it can be seen clearly...
  9. G

    Carb bracket

    I bought a bike to rebuild. The last owner already started taking apart the carbs, among other things. Now that I've put the carbs back together I'm missing the bracket in the attached picture. Any chance one of you excellent people have one? The bike is a 1980 XS400 SG.
  10. R

    Novice here. Need diagnosis.

    Hi all, I just bought a a 1980 xs400 special. I love everything about it. Except for the fact that it died the day after I drove it home. It kept acting like it had run out of fuel. (Yes there was fuel in it and yes I switched it to res.) All that to say, I’m pretty handy, though this is my...
  11. J

    Really struggling here...

    Hey guys, having trouble getting my bike to run smoothly, or at all. Some back story... Ive got a 77 xs360 with Mikuni BS38's. ive owned the bike for about two years and done fairly minor work on it, mostly just cafeing it. I usually commute about 10 minutes to work on it and never have any...
  12. Nichdoch

    ‘81 xs400 carb float question...

    So, I got into the carbs on my ‘81 the other day and honestly the worst I’ve ever seen. Gonna be completely rebuilding them. I am having trouble locating floats for the ‘81. Will the ones from earlier models like 77-79 work? I uploaded some pics of what I got versus what I was looking at buying.
  13. B

    81 floats

    Howdy, I recently took apart my carbs (mikuni kogyo) for a 81 xs400 to clean and found one of the floats were filled with liquid. I'm having a hard time finding floats for an 81 to replace it, and was wondering if a 79 or 82 float would fit? As those are the only floats I've been able to find...
  14. bricks

    Carb fuel inlet, general question

    Hello everyone. First post, thanks for having me :) A friend gave me a 1983 Yamaha xs400 Maxim (wohoo!) and I just started fixing it up. It cranks but doesn't start/fire, so I rebuild/cleaned the carb, re-installed, set the petcock to prime and let it sit for a few minutes... It still won't...
  15. C

    Carb issues

    i recently picked up an 82 xs400 that hadn’t been run in over a year. I got it running, got rid of the bad gas, and cleaned the carb. Even after cleaning the carb, the left side carb is still flooding causing it to hesitate and leak gas out of the air intake. Any suggestion?
  16. Aedan Graves

    Replacing carbs with non-OEM?

    Hey all, It's been a while since I've posted anything on the forums and I come with a question. The situation; I picked up my bike used Nov of last year, and the previous owner didn't at all take care of the bike, failing to do basic maintenance. As such the carbs needed cleaning or a rebuild...
  17. member14827

    1979 XS400 build with Mikunis -- carb advice needed

    Hey all. I picked up a low mileage but long-neglected 1979 XS400 for a song that the PO had started chopping up into a cafe build. The bike had been sitting for a long time and was not running. The cafe style is what I was going for anyway and I'm at the stage where I'd like to get her running...
  18. Dav-len

    Wanted - looking for a BS34 Carburetor,for a SOHC 1981 xs400 special.

    Good day all I am currently in Germany and was wondering if any one from up this side of the world has a SOHC 1981 xs400 special carburetor for me? I am leaving to go back home next week Thursday.
  19. K Braun

    Choke Rod Not Moving on 79 XS400-2F

    Hi all, New to this forum and new to the XS400 and I have hit a little snag in my carb rebuild/overhaul. its seems as thought he choke rod doesn't want to move more than like an 1/8th of an inch. Is there a process to pulling the entire mechanism and cleaning? I have watch many carb rebuild...
  20. frankyaxs400

    mikuni idle screw?

    hey everyone ive been having a hard time locating anything on my mikuni carb for my 1984 xs400 seca. our goal is to tune it when we get it on the bike im looking for the idle screw but cant seem to locate it, and ive created this account to get help with it. but anything will help...