1. S

    Newbie, Found this mystery little piece in the engine . . . (THE PLOT THICKENS!)

    Hey everyone! I'm a newbie, both to this forum and to working on engines. And to riding lol. I'd really appreciate any input on this. I made a mistake - I was taking apart the engine on my 1978 XS400 and as I was splitting the crank case, I found this little piece had fallen onto my workbench...
  2. Qwervo

    Lift / stand / lift table advice DOHC

    Hey fellas, I’m planning to do some work on the bike for the first time during the winter. Mostly maintenance, some electric fixes and some upgrades on the handlebar controls. I have a little storage room to work on the bike and the next step is to buy something to lift the bike to work...
  3. N

    Throttle Shaft Seal Replacement

    My 1977 xs400 needs throttle shaft seals to be replaced. Does that mean it needs a full carb rebuild? The previous owner said he "rebuilt the carb not too long ago." I'm guessing he either overlooked throttle shaft seals or used bad ones. What do y'all think?
  4. B

    Factory Service Manual 1979-1982 Hope it helps someone.. :bike:
  5. Y

    Does my bike have a transmission problem?

    I have an 82 xs400 maxim. Bike starts and runs great. The problem with it is when I'm riding. The throttle seems really touchy and jerky. It's very hard to keep a constant speed. Seems like it is always either accelerating or decelerating. when you play with the throttle (while riding) it...
  6. E

    Air Filter on a XS 400 Special

    Hi guys, i have a problem finding air filters for my motorcycle i recently bought. it seems to have a different airbox than the original one. It has a D-shape air filter, which i have trouble finding. Please help.
  7. R

    Help! Engine fitment 1984 XS400

    I need a replacement engine for my 1984 XS400 (XS400L), will a 1982 XS400J engine work or any of the XJ750 engines? Can anyone tell me what years of XS400 are compatible with my bike?
  8. Ketchup pusher

    HELP: Can i make a complete motor from these two?

    Hi there I'm new here, only just got my xs 400 last month. My plan is to make it into a cafe racer, but before i come to that i saw when i first got it that i needed to change the gaskets, no biggie, it was missing it's kickstarted axle too so i thought i might as well add that while i was at...
  9. brockd

    Looking for a mechanic/drinking buddy/XS-guru

    It's been a while since I've been remotely active in these pages as I 100% thought my XS was going to become someone else's project. We had an unlucky twist in June and were informed we'd be getting kicked out of our loft/apartment downtown. Between work, packing, moving, more work, and a...
  10. P


    Hey guys, I'm new on this forum! I'm a Montreal french guy so excuse my english. I just bought myself an old 1983 yamaha XS400 maxim (don't have good pictures yet) and I'm looking for your help and inspiration to change it into a nice ride since I'm completely new at this (first bike ever)...
  11. J

    First Oil Change

    Just bought a 1980 XS400 and you guys have been a great help so far and I appreciate it! Keep an eye out for build pics! Do you guys have a oil of choice? So, far I have been seeing everyone use different things... Rotella T 15W-40...15W-40... conventional or synthetic?
  12. C

    Introduction & mechanic needed in Chicago

    Hi all, My name is Caitlin and I am new to the forum. By way of an introduction, I live in Chicago (Avondale) and finally brought my 1980 XS400 Special II down from Stillwater, MN, where I was born and raised. My dad has been a small engines mechanic in MN since the mid-late 70's...
  13. brockd

    Ready to throw XS in the lake Pt. 2

    In keeping with Faniman62's theme - I'm now about to throw my XS in the lake. Knew I had a bad petcock ordered kit, waited for shipping (delivery was a nightmare), and repaired it Carbs sounded out of whack took them apart, cleaned, set to factory spec had gas in the...
  14. Y

    idles great but floods out as soon as its put in gear

    Hey guys, I picked up an xs400 the other week from this dude before i got my permit. the guy i bought it from started it up for me and it ran great, i revved it few times and all was good. i hauled it home and tried to go for a ride and thats where i ran into my problem. the bike started...
  15. J

    BS34 Float Bowl: Stripped Threading

    Hey Everyone, So i've slightly neglected my '77 s360 after recently purchasing a '76 cb750. attempted to get her back on the road tuned and ready. Set the valves, timing, and boiled the carbs. After cleaning the carbs in Berryman's i seemed to have left it in too long cause it was...
  16. Norman1950

    Kickstarter not working....

    Working on my bike last night and getting near the end of the build and decided to try to kick it over with the kickstarter. And it said nope... Kind of confused on this one... When I got the bike it would kick over fine. Just had very low compression. Got the top end machined and put back...
  17. G

    I think Oil Galleries are clogged.

    when I got this bike, first time starting, only cylinder fired and ran. Then I found the Valve cover plugs and put ATF fluid in it (High detergent) for two reasons. First, changed the oil and it was clear on the dipstick. So, if I was successful in clearing the galleries with ATF and running...
  18. S

    Engine seal kit specification

    Hi from Bangkok, Thailand. Because I'm not with the bike right now. I plan to rebuild my xs400 sohc engine in next couple of weeks. There is not the seal kit availalble here but there are many oil seal shops around here, so I would like to know dimensions of these engine seals. cb500 is give...
  19. Juju400

    I need help! 78 yamaha xs400 first bike problems!

    Broken spark plug in cylinder head. How can I get this out? It's really bugging me that this is keeping me from making progress on the bike. I've been reading I same that using penetrating oil might work or heating it up and then cooling it down might work? Advice please. I want to have this...
  20. B

    Bike loses 50% power when Throttle opens past certain point

    Does any one know what would cause the bike to lose significant power when the throttle is opened past a certain point? It seems to happen on all Gears but 1st.