xs400

  1. K

    79' XS400 no power whatsoever

    So I've been working on a project for about half a year now. I got the bike running a few months ago, just needed to rebuild the carb. I rebuilt the carb, and tried to start the motorcycle. The motorcycle tried to start but didn't. I added some gas, same thing again. It didn't start. Now there's...
  2. T

    For Sale - 1981 Yamaha XS400 Special with upgrades - clean title & current tags

    This vintage 1981 Yamaha XS400 is finished in black and is powered by a 392cc four-stroke parallel twin paired with a six-speed transmission. Equipment includes chrome fenders, 18″ alloy wheels, both electric and kick starters, front disc brake, preload-adjustable shocks, both side and center...
  3. M

    Can't Take It Off Choke

    So... This kinda feels like AA, "Hi My name is Mike and I have a problem." JK. But in all seriousness, I'm hoping a few kindhearted Journeymen XS-folk can lend me some knowledge. Experience level: Noob, like total, complete noob... Bike: 1981 Yamaha XS400HS BLUF: basically, bought diamond in...
  4. F

    Looking for XS400 front wheel disk brake conversion

    Hey everyone, just bought my XS400 yesterday for $600 bucks. The guy had a set of the nice black rims for sale to, so I bought those off him as well. I've seen a lot of posts from people asking about this, but I'm just wondering if anyone has an actual write up, pictures, or video of doing the...
  5. Chase Power

    Electrical bugs i really need help with

    Alright so this is my first post, i have a 1983 maxim xs400 and its a bit of a project bobber, im haveing some electrical issues come up that i havent been able to figire out in 4 years, the previous owner had only "shorten" the harness whatever that means and changed the taillights hook which...
  6. Davis Fowler

    New rider lookin for tips on ordering parts

    Hey everyone, recently acquired an 83 maxim 400. It needed some new front brake pads, a bleed, and fork seals replaced, which I was able to do rather easily with a friends help. really enjoyed looking thru some these threads and learning about these bikes, especially seeing all the progress in...
  7. C

    Having trouble with oil leaking from the crankcase

    Hello! I have a 82 12E model and it's been leaking since this winter. I opened the cover and it's a mess I read online that this is a common problem and it's usally from the clutch rod so I switched the oil seal but I find it hard to see where the leak is coming from. I went for a ride and...
  8. V

    For Sale - 81 xs400 yamaha for sale- original w/all extras

    Ok, so I had it in my head to get an xs400 and I did, spent a month and several hundred getting it running and right- it has 3300 original miles, came with (an ugly) faring as well as a cool piece of (keyed) luggage that sits on the back rack- original title, manual, all wires for that luggage...
  9. M

    Fixes for a leaky gas cap.

    I have a 1983 Yamaha XS400 SECA. I don't ever overfill the tank. But I noticed that when leaning the bike on tighter turns gas would dribble through the tank gas cap and run down the side of my tank. Now, I wasn't surprised by this. It's a 40 year old bike so I can only assume that some of...
  10. M

    "SECA" Etymology

    Hello everyone, I'm brand new to this forum and (somewhat) new to motorcycle riding. Last summer I got my license and purchased my first motorcycle, a 1983 XS400 SECA, and got in as much riding as I could before winter rolled in and I had to stow it away. Right now it is sitting silently in a...
  11. XS-KM

    XS-KM

  12. B

    Xs400 engine job

    Hi everyone! I've very recently bought an 83 XS400 Maxim, I did a compression test and have about 35 psi difference in between the two (sitting on the bike, left 130psi, right 95psi) proceeded to do a leak down test and concluded the compression is going into the crankcase. I haven't opened it...
  13. B

    Are Jets Universal?

    I think I need to increase the size of my pilot jet and maybe my main jet in my Mikuni carb on my bike. The main right now is 135 and the pilot is 42.5 which is stock I believe. I want to at least go up one size on the pilot as it seems to be lean and I cant fix it from changing the air/fuel...
  14. 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...
  15. S

    What Chain Do You Use?

    So I got a 1982 Xs400 Heritage. The current chain and I would assume original one on the bike now is a DID50DS. But I cant seem to find someplace to buy a new one anywhere because its discontinued. I have also tired finding a DID50HDSS but still no luck. I have seen from googling that people say...
  16. S

    Foamy oil

    I had 15w-40 in the bike before just for winter test runs. Decided to go ahead and buy Valvoline 20w-50 motorcycle oil in for the warmer temps now. But once I start the bike and it runs for a couple seconds, the oil becomes pretty foamy. Ive done some googling and what I have found is it could...
  17. S

    Inspection cap part number

    I am just pissed but I need your help. So I broke one of the valve inspection caps on accident. So I went on CMSNL and looked up a diagram to find which part I need to find and purchase. Well on the website, for a xs400 1982 Heritage, part 15 is the product number (1H21118600). So I found one on...
  18. S

    Piston Play?

    Back again to hopefully ask one last question so here we go. In this video here (LINK), you can see the piston has a fair amount of side to side play. It does not have any up/down or angular movement. I know the piston wont move like this in the cylinder, but from previous questions I have asked...
  19. S

    XS400 Knock Noise

    1982 xs400s Heritage Alright so I made a thread about this a couple weeks ago and asked for some suggestions on what the noise could be. I finally got the top end fully taken apart as I have been busy since then. This is the video of the noise for reference. So while the pistons have been off...
  20. S

    How To Remove Breaker Cover?

    Alright I may be an idiot thats missing something but how do I remove this cover? Nowhere in the manual does it show you how to remove it. I went on CMSNL and looked at a diagram on the cylinder hear and can see that there's 2 screws connecting it. I can easily get one of them out but for some...
Back
Top