1978 XS400-2E Intro and Build

Do I need to remove the valves to safely submerge the head in a solvent for cleaning? I am wondering if there are any bits I cannot see that are sensitive to solvents (gaskets, etc).
 
I doubt those valve seals would survive. they have a rough life.

I replaced mine with some nitrile ones from the states via ebay. much better
 
Ah, I see them in there now. Are the valves tricky to take off? I am also wondering if I can adjust the valves with the rocker cover off, or does the cam and rocker cover have to apply pressure to do this? I've never done valves before.
 
need a valve compressor to get the little collets out. keep them bagged to be replaced in their original guides.

I think this was discussed in this forum with homemade valve compressors using G clamps.

you can do a little clean up in there while your at it to smooth the gas flow in and out of the engine :bike:
 
What I did today so far... Oh, there are plenty of flaws in the glass, but, meh, I will work with it.
 

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need a valve compressor to get the little collets out. keep them bagged to be replaced in their original guides.

I think this was discussed in this forum with homemade valve compressors using G clamps...

Naw, we use "C" clamps over here. Why go all the way o the 7th letter when you can get the job done with the 3rd. By the way, that little punctuation that ends a sentence (usually) is a "period". You can keep your "full stop".
 
Which gasket set is better? I tried buying an Athena kit from several different merchants. All of them were out of stock and refunded my money. Partsnmore told me it would probably be a month until they get more.

There is a Japanese kit here: http://www.ebay.com/itm/Yamaha-400-...Parts_Accessories&vxp=mtr&hash=item53e9b37437

And a Vesrah kit here: http://www.ebay.com/itm/78-79-XS400...Parts_Accessories&vxp=mtr&hash=item2c5fb85ff8

And this "motor power" kit: http://www.ebay.com/itm/Yamaha-XS40...Parts_Accessories&vxp=mtr&hash=item2eb3a9e752

It should come with those o-rings. I would not reuse any gasket or o-ring, bad idea. Oh, I sent your cap out today should get it in a few days.

I got the cap today. Thank you! It fits perfectly and was in very good shape.
 
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Vesrah are a good make.

Motorpower looks OEM (coz itsa got japanese writing on it)

I'd go with either of them
 
I re-fiberglassed the seat pan and tail because I wasn't happy with how they came out. Since I needed more materials I decided to use the excess to make other goodies.

The headlight cowl will almost certainly be shaped further. I started with plenty of excess to cut it down for fitment/looks.
 

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Daily update:

The turn signal mounts in the front were tapped to 10 mm threads to accept generic chinese turn signals (covered in stand-alone thread). Also, I used body filler and sanded the crap out of my fiberglass body panels (save for the battery box because I don't care). I'm very impatient as I have mentioned before, but they turned out pretty well; far from perfect of course, but way better than my original seat.
 

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I think I would put that sheath into the stud more to protect the wires around that hard bend. It does fit all the way up the stud. The signals may get sent back, however, as the seller offered to pay return shipping.
 
Daily update:

Complete engine gasket set is in and so is the oil seal kit. The engine rebuild is underway; cylinder block is back on, the valves have been lapped, and the valves are being put back in at the moment. The exhaust valves looked pretty ragged before I started.

Oh, and the oil seal kit comes with 6 seals I believe, but I can only think of 5. Where does the last one go?

Kick start shaft, push-rod, behind small drive chain sprocket, on the cam behind the points cover, tach, and ?

Are oil seals lubed before being installed? I was going to lube them to prevent damage when installing.
 
I got a few things done today: The engine is in, the main wiring harness is routed, and many other parts are on.

To get this thing started I need a few replacement bolts for the alternator cover from the hardware store, the timing needs to be checked, and it needs oil. I'm a little worried about how all of the new gaskets are going to perform and whether this sucker will have any leaks.

I put the engine in with the bike standing up and it was very easy with a second person. From a crouched position I picked up the engine with 80% of the weight on my right arm. My right arm was wrapped around the cylinder block and my left held on to the kick start shaft. I did not have to reposition my hands at all because my right arm fits between the frame and the cylinder block even with pipe lagging on the frame. My helper just inserted the bolts. The entire process took about 2 minutes. You'll need some upper body strength for this to work, because you cannot hold the engine against your chest.

The photo looks pretty dark, but it's something :thumbsup:
 

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looking good BC.. I'm about to embark on all this myself.
Where did you get the oil seal kit from? Which brand of engine gaskets did you end up going with? I'm assuming one kit of each does the whole motor??
 
I went with the Vesrah engine gasket set on ebay; it appeared to be very good quality and was made in Japan. Everyone seems to be out of the Athena kits at the moment.

The oil seal kit (6 seals) was also on ebay sold by dream305 in Canada. Even at $40 shipped it seemed to be much cheaper than buying them all individually. Most places want something like $10 per seal and that does not include shipping.

So far the only thing I noticed was that engine gasket sets do not include a starter cover gasket or neutral switch o-ring. I'm sure there are other bits that are not included, but that is all I noticed in a top-end rebuild.
 
So far the only thing I noticed was that engine gasket sets do not include a starter cover gasket or neutral switch o-ring. I'm sure there are other bits that are not included, but that is all I noticed in a top-end rebuild.

they are not part of the top end, so won't be included anyway! :D
 
Chinese foot pegs! They only took 2 weeks to arrive and cost 9.99 shipped. I bought the other bits from a hardware store.
 

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