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I got my 81 xs400 running WOOO!!!


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Hey guys, I just got my 81 xs400 running YEAAAA. My friend helped me a great deal since he has a xs650 of his own. Anyways I come in need of help. I am trying to find out if the contact breaker cover sits on a gasket. I have a old haynes manual that covers xs 250's or whatnot to 400's so the general pictures looks like it needs a gasket. But when I look at bike bandit and drag up the parts, it does not show a gasket on it. So does it have it for my model or it does not? Also I need a engine bolt for the lower mount, does anyone know if earlier years can fit it? I bought some bolts off ebay and it seems a little short. Do latter years fit? and last but not least I am trying to find a new petcock for the tank, does a 650 petcock work?

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Cut a gasket from gasket paper, about 5 dollars roll at the auto parts store. Cheaper and faster than ordering one.

Go to Lowes or Home Despot and match up the lower bolts, they have them. Just get the same grade as what you have so it does not break. Use a nylon inserted lock nut down there because there is a lot of vibration..

And congrats on getting it running.

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Hey guys, I just got my 81 xs400 running YEAAAA. My friend helped me a great deal since he has a xs650 of his own. Anyways I come in need of help. I am trying to find out if the contact breaker cover sits on a gasket. I have a old haynes manual that covers xs 250's or whatnot to 400's so the general pictures looks like it needs a gasket. But when I look at bike bandit and drag up the parts, it does not show a gasket on it. So does it have it for my model or it does not? Also I need a engine bolt for the lower mount, does anyone know if earlier years can fit it? I bought some bolts off ebay and it seems a little short. Do latter years fit? and last but not least I am trying to find a new petcock for the tank, does a 650 petcock work?

No gasket required on that cover. The units that had points under there did, but the electronic ignition models don't use a gasket there.

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you can get the lower bolts from yam dealers still!

you can also get pet cock rebuild kits off ebay

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I got a 77 point cover which might seem to work, but can anyone confirm?

drewpy I called Pasadena Yamaha and they said they discontinued almost all the parts that I was looking for!

I am trying to find a nice looking gas tank still, the current one I have looks too cruiserish but its hell trying to find the 77 square gas tank without paying it through the wazoo.

Also anyone know if those ebay "universal" rearsets work on the xs? I can't justify paying for those rassak rearsets that cost more than my bike.

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I got a 77 point cover which might seem to work, but can anyone confirm?

drewpy I called Pasadena Yamaha and they said they discontinued almost all the parts that I was looking for!

I am trying to find a nice looking gas tank still, the current one I have looks too cruiserish but its hell trying to find the 77 square gas tank without paying it through the wazoo.

Also anyone know if those ebay "universal" rearsets work on the xs? I can't justify paying for those rassak rearsets that cost more than my bike.

still listed mate,

http://www.georgiawatersports.com/

http://www.nwvintagecycleparts.com/

SKU: 95821-10145-00

BOLT, FLANGE

as for the square tank, there are loads in UK ebay!

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still listed mate,

http://www.georgiawatersports.com/

<a href="http://www.nwvintagecycleparts.com/" target="_blank">http://www.nwvintagecycleparts.com/</a>

SKU: 95821-10145-00

BOLT, FLANGE

as for the square tank, there are loads in UK ebay!

thanks! I finally got a tank for 150, I'll take pics of the bike tomorrow to show you the condition of the bike.

So does anyone know if the 77 point cover will work for a 81? The 81 does not have points though but what it does have is a contact breaker or ignition timing sort of deal. When I start up the bike there is a small hole that forces oil out which is a bit strange. Is this suppose to happen?

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thanks! I finally got a tank for 150, I'll take pics of the bike tomorrow to show you the condition of the bike.

So does anyone know if the 77 point cover will work for a 81? The 81 does not have points though but what it does have is a contact breaker or ignition timing sort of deal. When I start up the bike there is a small hole that forces oil out which is a bit strange. Is this suppose to happen?

should fit as the holes are the same and I dont belive yamaha changed their castings.

I think you also have a camshaft seal gone, but check first that the camshaft doesn't rock whilst still bolted in the head!! ( worn)

drewps

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ok sorry guys for the late reply, I went to a wedding up in san fran so I have not been able to take the pics yet. Anyways the 77 point cover came but what is strange is that it has 2 small holes on the bottom. My problem is that there is oil leaking out (it didn't have a cover). Is it suppose to leak oil like that? Also drewpy I believe the camshaft seal is ok because the guy I bought it from got it professionally rebuilt and never put the engine in.

edit: also I forgot to inform you guys that I aquired a 1977 xs400 tank which is more boxy and square than the usual cruiserish round tank. Which one should I mount on for a cafe racer? I am planning to have a round bullet hump shaped fiberglass seat (unless someone can convince me to a better looking seat) and a candy apple color scheme with ducati stripes on a standard flat black frame. I am also tossing around the thought of a regular ducati red color scheme. Does anyone know any good replacement rear shocks? I have been looking at progressive 412 shocks but they are a pretty penny. Oh yea also exhaust too, I have no idea which one is good.

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ok sorry guys for the late reply, I went to a wedding up in san fran so I have not been able to take the pics yet. Anyways the 77 point cover came but what is strange is that it has 2 small holes on the bottom. My problem is that there is oil leaking out (it didn't have a cover). Is it suppose to leak oil like that? Also drewpy I believe the camshaft seal is ok because the guy I bought it from got it professionally rebuilt and never put the engine in.

oil shouldn't be leaking out and it can only come from the camshaft seal or the joint between the cam cover and head which has no gasket or sealant. I have 2 small holes on mine andI assume they are in case of water ingress/condensation

edit: also I forgot to inform you guys that I aquired a 1977 xs400 tank which is more boxy and square than the usual cruiserish round tank. Which one should I mount on for a cafe racer? I am planning to have a round bullet hump shaped fiberglass seat (unless someone can convince me to a better looking seat) and a candy apple color scheme with ducati stripes on a standard flat black frame. I am also tossing around the thought of a regular ducati red color scheme. Does anyone know any good replacement rear shocks? I have been looking at progressive 412 shocks but they are a pretty penny. Oh yea also exhaust too, I have no idea which one is good.

For a cafe racer, i recommed the xs750/850 three's one on youtube and it looks great.

http://www.youtube.com/watch?v=Owwd19VDbpg

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oil shouldn't be leaking out and it can only come from the camshaft seal or the joint between the cam cover and head which has no gasket or sealant. I have 2 small holes on mine andI assume they are in case of water ingress/condensation

For a cafe racer, i recommed the xs750/850 three's one on youtube and it looks great.

http://www.youtube.com/watch?v=Owwd19VDbpg

would it also leak out because there is too much oil? My buddy told me to put a half a quarter more oil in it since it hasn't been started since 94. Also if it is the seal do I have to tear the head down?

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I removed the contact breaker and all I see is the camshaft rod, there is suppose to be a seal there so the oil doesn't come out right? Would I have to open the head to put the seal in? or is it just a knock in job?

please don't overfill as you'll blow oil seals due to the pressure build up.

to replace the camshaft seal, you only need to take off the cam cover and you can do it without removing the engine or anything daft like that. get the manual that's posted atthe top of this section as it gives the order which you undo and tighten the bolts to stop the cam cover warping.

tank off, top mount off, tacho cable off, cam cover off.... sorted!!

so much for "professionally" rebuilt engine!!

drewps

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WOOO I found the O-ring in the bin. and plugged it in. Now I am leaky free!!! yay!!! Thank you so much drewpy. Now I have another question, the headlights are dim should I be worried? its a new battery and I can kick start it in 3. Also I am missing exhaust flangers, do they help fit the headers to reduce noise? Because so far its super loud and think it is because of a small crack in the headers and no flangers.

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WOOO I found the O-ring in the bin. and plugged it in. Now I am leaky free!!! yay!!! Thank you so much drewpy. Now I have another question, the headlights are dim should I be worried? its a new battery and I can kick start it in 3. Also I am missing exhaust flangers, do they help fit the headers to reduce noise? Because so far its super loud and think it is because of a small crack in the headers and no flangers.

flangers? do you mean the collars that hold the exhaust to the head? yep you would need those to get a gas tight seal!

a dim head lamp could be a bad earth lead, so check all your black wire's connections and the bit under the seat where it touches the frame, make sure there is good contact (remove and scrape)

does the headlamp get brighter when you rev?

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nope, it gets dimmer when I rev it but that is the least of my problems right now. I started the bike today and a buch of whiteish smoke came out super thick for a good minute. I had to turn it off because it looked like the house was on fire instead! But I suspect it is because I put too much oil. So I removed the excess oil and it does seem to smoke a lot less, but it is still a bit smokey. I can't get it to idle without choke but I will take care of the jets needles and stuff later. Do you guys know what is the average compression for a xs400? I am getting 125 left and 127 psi, is that good?

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I removed the exhuast today to check the valve stems and the right one (the one that spews smoke) seems to be clean,but the top of the valve stem seems leaky, I can tell because the carbon deposits look wet. The left one however looks really gunky and leaky from the top, but that is the part that does not spew smoke. Does this mean the valve stem seals are leaky? It has been sitting in a hot dry garage for at least 10+ years.

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I removed the exhuast today to check the valve stems and the right one (the one that spews smoke) seems to be clean,but the top of the valve stem seems leaky, I can tell because the carbon deposits look wet. The left one however looks really gunky and leaky from the top, but that is the part that does not spew smoke. Does this mean the valve stem seals are leaky? It has been sitting in a hot dry garage for at least 10+ years.

I would say the stem seals are leaky as they will have dried in storage. its a head off job and valve spring compressor with top end gasket kit!! decoke the engine whilst your in there ad lap in the valves.

the compression is 156psi with 14 psi difference between the 2 cyls

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