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My XS400 "restore"

Discussion in 'The Garage' started by SoulMan, Jul 4, 2018.

  1. SoulMan

    SoulMan XS400 Addict

    I havent gotten around to trying to start it yet. I did go through the mix container of parts the previous owner included. I am not sure of what these things are. Some are obvious like foot pegs etc but others arent. Not sure where they go even if they are. Looks like I am definitely in the end going to need to buy set of mirrors unless its normal for mirrors to be different lengths. Will need front and rear turn signals. I repaired the brake light, the clear reflector inside was broken off the red portion of that component, but it is missing screws to attach the actual red piece to the part that holds the bulbs. Anyone know the length and types of screws for that? I think there were some components in there that arent even part of the bike. Looks like a red reflector from a bicycle haha. Its all a mix match of parts. I dont know if all the bolts etc that were removed from this bike were even in the container. I have heard you can buy a whole set of bolts etc. Anyone have a line on that?

    I am not sure what some of these components connect to. Maybe the PO replaced them. the silver thing with three holes and a bolt up top (what is that? - research tell sme its a wheel adjuster but the ones I see online only have two holes so I am not sure about this one).. the black thing with two squares on one side and a hole on the other (I am guessing a battery holder - when reading about the air intake filter boxes I found out this must be the bracket for those. Looks like I only have one :( ) The two metal pieces with black on them with an end that looks like it wraps around and sticks inside the other end. The rubber piece with three metal rings inside it. The black piece with two bolts and a rubber portion on the other side (guessing exhaust bracket?)


    Not about this one. My first guess would be a brake cylinder. I think the brakes work on the bike from my previous testing.

    Looks like these are air intake filter boxes. Looks like I am missing a part on thtusingt right one.

    Petcock? I think the PO installed a different one onto the bike.

    Some hoses etc. Looks like one is def the 1/4 inch fuel line. Not sure about the one with a reservoir

    Pack of some sort of gaskets and such. I did not open then. Not sure what they are for yet :)

    one is a foot peg the other three are I dont know exactly. Sprocket/gear of some sort. The other with the two pieces that slide at an angle to each other to each other actually looks like a tool not part of the bike (can anyone confirm).


    Front wheel fender. Need bolts/screws for that tail light housing to mount the red and clear lens to the ho if anyone knows any specifics about them that would be great.

    Sorry I am a noob. :) Well one is the speedometer cable. I can look to see if there is a connection already made for the speedometer. I think this is considered the tci and an ignition coil. With how they are cut I think the PO probably replaced them. Locations would be good so that I can confirm.


    I actually do not know where this goes on the bike. So if someone could give me the location that would be great so I can see if the PO replaced it with a different one.

    20180714_191738.jpg 20180714_191744.jpg

    I don't know if these are stock shocks or what.

    To start the bike I just need the following hooked up:

    1. battery
    2. ignition switch - kill switch
    3. rectifier (where is this mounted?)
    3. alternator (where is this mounted?)
    3. regulator (where is this mounted?)
    4. two coils ( I think I saw this mounted under the gas take on the frame - correct?)
    5 pu coil (where is this mounted?)
    6 carbs :)
    7 filter boxes (I assume if I want I can run without these for a few minutes just to see if it will start - I would love to hook them up but I don't think I have all the parts I need to do so.)
    8 throttle cable

    Not riding it just trying to start it. The kick start is there already. Not going to use the starter as I don't know how much juice the battery I will use during the test will have.
    Last edited: Jul 15, 2018
  2. NewHavenMike

    NewHavenMike 1976 XS360C Top Contributor

    It looks like you could have some Kawasaki parts mixed in there, based on that ignition unit. My first thought was Honda though based on the shocks.

    The bag with the O-ring is a top end seal kit. The red O-rings are for the cylinder base, the metal caps are lifter seals, and the 4 slightly smaller O-rings look like they could be for the tappet covers.
  3. SoulMan

    SoulMan XS400 Addict

    Good to know. I will look over the bike and try to find the various components there. :)

    Based on the picture with the oil on the engine I suppose this makes sense. I assume the PO bought that to fix the oil leak. If that is true that will be one thing I dont need to buy.

    NHM I really appreciate your responses!!
  4. SoulMan

    SoulMan XS400 Addict

    So last night, I along with my engineering brother in law, started looking at the bike. I was going to see if I could start it but my BIL knowing there was a short said "Check and see if its shorted". So we checked across the positive and negative connections and saw it was shorted. It ended up not being shorted, at least not on that connection, as we finally realized later on that we were checking for a short between the ground and the cable that was going to starter motor. My BIL said that the way the starter has very low resistance it would look like a short. But we also did check for a short between the negative and each sides of the fuses. We found that turn signal circuit is where there was a short. I did some multi-meter testing on various components and ultimately it looks like the turn signal cancel component had failed. Once we unplugged that component the short went away. Also found out that the PO had replaced all the 10 amp fuses with 20 amp fuses. I doubt it was the main fuse that was blowing... at least not at first.

    All that being said, before hooking up the battery we were trying to see if we could get a spark on the plugs. Never was successful. Then we hooked up the battery. To check for spark we pulled the plug and grounded the threads of the spark plug then kicked the bike and we were not getting a spark. I was trying to find all the components to see if the necessary electrical components were there to get it started. The ignition coils are there. The rectifier, the regulator. Not sure I ever found the pickup coil. Any tips on what to check with regards to the system to try to diagnose the issue would be greatly appreciated.


  5. Petew

    Petew XS400 True Believer Top Contributor

    Your brake" cylinder" appears to be a carburetor and throttle cable, not the normal one used but I have seen them as replacements online.. You should print off a manual from here for your bike it will save you tons of time and you get a good education about how things work. It helped me immensely.
  6. SoulMan

    SoulMan XS400 Addict

    Thanks. Both the front and rear brakes work. So I think that must be an extra component for some reason. I did think it kind of looked like a carb. I guess I probably could have looked for some markings. I guess i was thrown off by the fact it had two cables on it.

    Edit: I wanted to edit this and say that I appreciate your response. I went back and looked at the manual and now I know where the pick up coil is located. Thanks again!!
    Last edited: Jul 17, 2018
  7. SoulMan

    SoulMan XS400 Addict

    Status update. To repeat I think we found the short which I am happy about. It was a bad turn indicator canceller

    When I did my testing with the brother in law I took the front head light housing off which meant unplugging the connections up there. I noted during our testing the neutral switch light never came on. This morning I realized that I had not reconnected the connections which complete the circuits up there. Connected a battery and I turned the key on and the neutral and oil warning light came on. I pulled the right spark plug and grounded it to the engine and got spark. I did the same with the left and got no spark.

    Does anyone know what secondary coil resistance should be roughly including the caps? I know now you are suppose to test without the caps but I did not know that a few minutes ago when I was at my brother-in-laws testing the coils. What I found was primary resistance on both coils was 3 ohms and secondary resistance (with caps) on the right coil was a little over 24 kohms and the left coil was 28 kohms. During my spark test I saw spark on the right side but not spark on the left. I clipped off a bit of the spark plug wire on the left, put the cap back on and got the resistance down to about 26 kohms.

    I also found out that somehow my jumper cable failed. The positive no longer has continuity which is strange so that could be part of the reason I wasn't getting spark on my left side test. Might have something to do with the fact that I connected the starter motor up to the positive of the battery for a period of time. It did not crank which is odd so I might have fried the starter motor. Have to test that out a bit more and connect it to the starter solenoid like it is suppose to be connected but for now there is some progress.

    Edit: just worked on the jumper cable. The wire seems fine. I think it twisted in the handle just enough to stop making contact. cutting the end and re-crimping it seems to have restored their basic functionality. Next step will be to retest the left side of that bike. I am still curious about my expected ohms though. Next time I will pull the caps off and test then and then test the primary.
    Last edited: Jul 20, 2018
  8. SoulMan

    SoulMan XS400 Addict

    So tested the secondarys without the caps. Resitance on left and right was 20 and 18 respectively. I removed the spark plug wire from the ignition coils. Both coils from the plug to the hole where the spark plug cables are inserted tested at 8.5KOhms. I assume i should replace these wires with low resitance plug wire. Both caps tested at about 8kohms or so. How does that sound?
  9. NewHavenMike

    NewHavenMike 1976 XS360C Top Contributor

    If im not mistaken, the caps should be 5 ohms. But you dont need resistor caps if you use resistor plugs.. the coils should be around 4ohms and 9.5k ohms.

    New coils are around $25 each, boots are around $3 each, wires are maybe $3 a foot.
  10. xschris

    xschris a lifestyle not a trend Top Contributor

    80-82 coils should be around 3 ohm primary and 8.6 secondary. Test with the wires removed. Use copper core wire when you replace them. I run non-resistor caps and iridium ngk resistor plugs. Both can be found off ebay for cheap.
  11. SoulMan

    SoulMan XS400 Addict

    Thanks you two .I picked up some new copper core plug wire and some new caps. I was too busy to wire it all up and check for spark again. Hoping to get to it tomorrow. I feel like im close to actually trying to start it!!
  12. SoulMan

    SoulMan XS400 Addict

    I did get it started. It will only run with full enricher. From everything i have read that means he carb needs to be thoroughly cleaned. Thanks for all the help.
    Last edited: Jul 24, 2018
    Petew likes this.
  13. SoulMan

    SoulMan XS400 Addict

    Update on my work. I cleaned the carb in the ultrasonic cleaner and put them back together with a new rebuild kit. Broke one of the float posts in the process but I think it is holding for my testing. I will need to resolve this in the future but for now the float pin is in pretty solid due to how my float post broke right in the middle of the pin mounting hole. I tried to fire it up but it didnt kick over. I did have the starter clutch off to replace the springs because the starter wasn't working well. I took the starter motor off but now I cannot get it to the point where it will work once I put it together. The motor spins until I put it back together and then it locks up pretty tight once the case is tightened down. The armature tests out fine. I don't know what I am missing here. If someone has a 1980 starter that they are willing to take apart I would love to see what the components inside look like and the order it is all put back together. I worry I lost a piece or something. I need to test for spark again but I need to get my stator rewired properly and then make sure not to pinch the wires when putting it back on the bike.

    Answered my question about tires:
    In the manual = Front: 3.00-18 | Rear: 120/90-16 tubeless for the xs400g

    Noticed the state of my tires today. What would have been the normal size tires that would go on these bikes when they came out of the factory? Mine has a 130/90 16 on the rear and it looks like its pretty close to rubbing the chain. That being said it *has* to be replaced because its pretty cracked all around. The front is a 90/90 18 and it is in better shape but when I get to the point where I will ride this bike I am sure it will need to be replaced as well. So if someone has the sizes I would appreciate it. Thanks!
    Last edited: Sep 19, 2018
  14. xschris

    xschris a lifestyle not a trend Top Contributor

    90/90-18 up front and 120/90-16 rear is stock and I would stick to that. It don't matter on tube or not tube tires as you need to run tubes anyway. If the tires are old get new ones along with rim band and tubes. It would also be a good idea to have the wheel trued and balanced while your at it.
  15. SoulMan

    SoulMan XS400 Addict

    So my update is that i got a replacemrnt starter from xschris and I used it to figure out my exosting starter. It turns but turns very slowly. I think it need some cleaning of the contacts to get working properly. That being said I installed the carb bavk into the bike and the new starter but it wont start now. I think that it is a fuel issue because if i spray a little sttarting fluid into the intake I could here it start to kinda fire. I am prettu sure the carb was cleaned well. I bought some tubes to do the float setup and will be making a manometer to balance the carbs. Also will be doing some type of aux fuel tank to use for the balancing. Does anyone have recommendations to try to get fuel flowing? Tp set the needle valves here is what i did. With the springs off i screwed the valvues in until they were fully seated. Then i unscrewed them 2.5 turns. Then i measured the distance of the screw from the carb body with a caliper and took note of the orientation of the screwdriver slot on the carb. Then i unscrewed the needle valve completely and put the spring back on and the screwed it back to the same spot. In trhing to get it running i adjusted them out 3 turns then 3.5 turns. No luck.

    I washed the carb in the ultrasonic cleaner and the jets did look clean. So at this point idk where to start. I do have spark and confirned that was the case. I assume if the float height is too low it could be restricting the flow of gas past the float needle. Thoughts?
  16. MrStubb

    MrStubb XS400 Addict

    I'm sure I may be jumping to conclusions but PLEASE tell me you didn't tightly seat your needles!! You should only turn them till you feel them litely seated with the springs installed. Then gently back them out 2.5 turns. This will get you in the ball park. The needles are delicate & will seat differently from 1 to the other because of machining differences and wear. So you wouldn't be able to get an accurate setting using a caliper. Also if your float is set too low you will actually be starving the engine at higher rpm. I don't remember off hand what the float level should be but what you need is enough fuel in the bowl and enough throttle for fuel to be drawn up through the idle circuit into the venture. Another issue is how your diaframs & high speed needles look. If they're torn or worn you'll also have tuning issues
  17. xschris

    xschris a lifestyle not a trend Top Contributor

    Always set your pilot mix screws with the spring washer and o-ring on them. Float level is 26 +- 1mm for brass floats. There are threads on this in the forum. You should always have air boxes on the bike for starting otherwise it will be very lean. Make sure the plugs are new and clean and you have 125-150+ compression.
  18. SoulMan

    SoulMan XS400 Addict


    I did not tightly seat my pilot mix screws. The diaphragms and needles looked fine.


    My pilot mix screws dont have orings. The carbs are 79s based on what you told me earlier. I havent set float height so I will definitely have to make sure that is correct. I also know that the plugs arent new and clean so I should probably put new plugs in.

    Thank you both for your responses.
  19. xschris

    xschris a lifestyle not a trend Top Contributor

    Ok, if you have the 77-79 carbs with the long exposed mix screws you should still set them with the springs in them. Go slow and be careful. Use a bit of oil on the threads and make sure they are clean. It will make turning them much easier. Make sure the tips are not broken off in the bodies and are still pointed straight.

    Have you replaced the pilot jet screw caps?

    Attached Files:

  20. SoulMan

    SoulMan XS400 Addict

    I did install screw plugs and washers which I bought off ebay. When I get a chance I will look into these recommendations! Thanks!!

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