New xs400 problems.

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Hello everyone, I just picked up an 80 xs400. It looks like it has been sitting for quite a few years so the first problem is to get it running. It has a new battery in it, im getting power to the starter relay, fuse box but when I turn the key on I get nothing. At first I thought maybe the cluster was bad but pretty much nothing up front is coming on. One of the things I noticed when I put the key in is you dont have to push down to turn it to ON and the turn is VERY short. Although the OFF and ON labels are printed pretty close together it still seems like it should be turning more or there should be a click or noticeable feel when you turn it to ON. Is this normal or should I look at a bad ignition? Thanks in advance.
 
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Time for a wiring diagram and a test light.:)
If you don't think the switch feels right then I would start there.
I don't recall the switch being a common problem though.:shrug:
 
I've never owned anything this old before so I guess thats why it felt weird to me, I really have no experience to back that up. After further diagnosing I found at least 1 bad fuse. Switched it out but still nothing. Im in the process of replacing the fuse box with in-line blade fuses. It looks like the wiring harness has been gone through at least once as I found some questionable stuff in there.
 
The old bulb fuses may be bad and visually look fine; they can burn out under the metal end caps and you can't even see it. Did you get a voltage on your battery or simply take someone at their word that it's new and charged?

My ignition has clear and distinguishing positions when the key is turned.
 
Ya I noticed that with the older fuses, that was my main reason for ditching them and wiring in the new in-line fuses. Im not the greatest when it comes to wiring diagrams and everything but i've been looking over them for a while now. Im getting power from the the main fuse, when I turn the key on should I be getting power from IGN and Headlights fuse as well? As far as the battery goes it came out of my brothers kz650 and its fully charged.
 
I guess it was the fuses giving me problems. Pulled out the wiring harness and checked it over, wired in the new in-line fuses and I've got power! Im only going to keep the speedo so I've got to figure out whats up with it but the Neutral/oil lights lit up. This took alot of courage for me to do this, once you have all these wires spread around it can get overwhelming. Thankyou for the help guys, I really appreciate it.
 
Im looking at buying some new parts for it from Parts N More. It wants me to click on which xs400 I have. Mine is an xs400 special. So would that be the xs400s? Sorry im sure this sounds dumb but I didnt realize how many different versions there were.
 
I am not sure about the 's' designation, but there is a workaround on their site. Go to Yamaha, then click 'xs400' (no letters after it) and once there on the left side is a column of years. You can then filter all parts by year.
 
Alright so Im getting ready to start this thing for the first time. I just drained the oil and there was about 1.5gal of it in there. It smells like gas and its pretty thin. I dont know how long its been like this since I've only had the bike for a couple weeks. Should I be concerned about anything?
 
A 1980 is generally an XS400G- a "special" would be an XS400SG. There is supposed to be a little over 2 quarts. As long as your carbs and petcock are working now, I wouldn't worry. Because motorcycles with carbs are gravity fed, if the petcock is not turned off, fuel can seep into the intakes and through the cylinder to the crankcase. If the float needle is dirty, the floats are set wrong, gas can run in faster. That's something to check.
 
Thankyou that will help me out a ton, although most of the parts I need are pretty much the same. The tank was pretty empty when I got the bike so that was my thought as well. I haven't had a chance to mess with the carbs yet but my bro (he was the one who bought the bike for me and delivered it) took them apart and cleaned them. The throttle is still a bit sticky so I guess more cleaning is needed. I picked up some more oil, should I change out the filter? Normally I wouldnt ask such a dumb question but considering I probably cant find them locally it will have to be ordered.
 
Personally, I would plan on getting filters and changing it before I put too much time on the engine, but for getting it started and running it to check for issues, I'd say I would not worry about it. I would, however, take the screen out and change it and take the filter cover off to make sure there's no gunk in there.
 
Still havent got around to starting it, aside from needing new filters the wiring still needs to be ran and I need to find a permanent spot for the battery. Heres a pic of it, stretched the swingarm 5in.



 
I just changed my oil and i too had about 1 gallon of oil mixed with gas. really thin and smelled of gas. I changed the filter which i got at a local yamaha cycle shop/dealer for 10 bucks. The screen was pretty clean so i just blew it out with compressed air and put it back in. Im beginning to believe it is normal to see this issue with bikes that have been sitting around for a long time. Would the inner engine parts be ok with fuel/oil mixture sitting in there for a prolonged period of time or is it time to take the engine out and rebuild it?
 
Alright so im getting to ready to order all the parts I need. Parts N More is out of the stock filters so I was thinking now would be a good time to go to pod filters. A: what size do I need? B: what do I do with the engine breather ( I think thats what its called).
 

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54mm, but measure yourself before you order. Always double-check. If you're not using the stock intake tubes avoid emgo filters.

Get a crank case breather filter for the vent. I believe it normally dumps back into the intake so as to re-burn whatever junk is being vented for emissions purposes. The small crank case breather pods can usually be bought at chain auto part stores. They fit with effort.
 
Thanks for the help so far everyone, I ordered the emgo filters and will use the stock intake tubes. I should be able to try and start this thing next week.
 
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Anyone know if the honda cl exhausts will fit our bikes? Im really diggin the way they look. Im sure I could make something similar but a bolt on would be nice.
 

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Stay away from scrambler exhausts unless you can bend pipes. These have been a nightmare for a friend of mine who has a cb360. The scrambler pipes have very, very tight clearance normally. The ones he has are even made for another very similar honda.
 
Nope cant bend, but I can cut and weld. I would imagine it wouldnt be very fun to accidentally lean your leg on it while riding but damn does it look bitchin. Trying to get some ideas for my exhaust, the mufflers were rusted through so I had to cut them off.
 
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