Smiles' Top End Rebuild Thread

smiles79 said:
But I would not want to run it until I can break it in, correct?
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My opinion... I'd run it. several times. Reason being, you want the oil to splash around and coat everything that you cleaned and is not currently coated. Otherwise you're looking at internal corrosion. Getting it hot opens the "pores" of the metal. Coating would be more thorough.
 
No, I don't think that would matter. But, then you'd have carbs to drain and set up for winter storage. I imagine they're all drained and dry right now. *Edit - but Jim makes a good point about thoroughly coating everything with oil, and having it hot during that.
 
Think of it as an adventure............As long as there is no ice on the road.

Wouldn't be a bad thing to run in the air cooled engine in a cooler environment............
 
Besides, You do all that work doing the top end and you will want to hear the fruits of your labor. Maybe get that ride in before the first snow or ice on the road..
 
Initial run on a fresh overhaul will be hot, rings breaking in. Shut it down when it gets hot, maybe a couple minutes. If it doesn't start and run, problems. Tackle those now during the winter nonriding/rebuild period...
 
Does anyone have any advice for removing the rocker box stud hole sleeves? They seem to be stick in there, would a little heat be safe?

Also, the o rings that I got in my kit that seem to be the right fit are a little thinner than the stock ones. Also they're black instead of red. Is this ok?
 
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Honestly, if you don't plan on pulling the rocker shafts and rocker arms, I wouldn't even disturb those sleeves. And there's really no reason to pull the rockers unless some are bad and being replaced. Undisturbed, I think the originals will continue sealing just fine. Besides the o-ring, you're going to have gasket sealer all over the bottom lip of that sleeve too when you reassemble things.
 
Didn't mention earlier, I got the can chain guide installed earlier today! It's centered-ish, but I'll double check it when the jugs are on.
 

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Carefully measure the gap between the side of the guide and the tunnel on both sides, and where the guide sticks out of the cylinders at both the top and bottom .....

o0c8evP.jpg


It's often asked if the guide can be replaced without pulling the cylinders off. My answer to that is no, not if you want to be sure it's mounted straight. There's no way to check/measure the bottom if the cylinders are in place.

I've been gathering together the old, trashed guides I have. So far, I've found 5. 4 out of those 5 show rub marks on the side rails, evidence they were mounted crooked. As far as I can tell, these were all original factory installed guides. What this is telling me is that Yamaha didn't even bother centering these things when the bikes were produced, lol. We can do better.

JlrMHuF.jpg
 
There's some play in the holes in those chrome fittings that the guide mounting bolts go through, so the guide can move right and/or left a little bit. I lightly snug up the bolts and then I can push the guide left or right to center it, then tighten them the rest of the way (to the torque spec). I always measure again after that to make sure nothing moved.
 
Superjet, what Mamayama knew and what she did are two different things. A lot of folks don't like to hear this, but the XS650 was not a class act. It was a price point bike, built to be the cheapest cc. per dollar on the road. I was selling for a Honda-BSA dealership when the XS1 came out. I didn't lose one BSA sale to the Yamaha--most guys who bought Brit wanted handling, and it took serious money and knowhow to get that out of the XS1.But it tore me up on Honda 450 sales--$50 for another 200 ccs.
 
Alright, it's been a minute but finally got some more work done. As it currently sits, I've got the pistons, cam chain, and cam chain guide installed. The jugs and head are sitting on the assembly, but nothing is torqued. Will not torquing everything down within a certain amount of time affect the sealing ability of the gasket sealer and copper spray? I sure hope not, it's getting cold out there.

Also, are the exhaust gaskets in the head, or are they what's stuck to the head pipes?
 

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As long as you used a non-hardening sealer, you should be fine. Your exhaust gaskets are missing.
 

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