Smiles' Top End Rebuild Thread

Got to looking at the cam chain tensioner a bit closer tonight, am I missing some plastic on the back side?
 

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Valves have been lapped! The seats seemed to be in good shape, no pitting. Does anyone k ow what the discoloration is in the picture? It doesn't seem to want to wipe out.

Lastly, am I missing some plastic on the backside of the cam chain tensioner? It's hard for me to tell if it looks as it should or not.
 

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I think your tensioner is fine. The missing rubber bits are not in an area that does anything. I don't know what all those spots are from in the ports, maybe from the cleaner you used?
 
Sweet, thanks for the input. Do you think it's something that needs to be cleaned up or if it does seem dirty or gritty will it be alright to leave it?

Jim, I built a box like yours and pressed that sleeve most of the way back into the jug. I think I'll try to sandpaper method to flush everything up. I think I've read that 320 is the way to go?
 
If it feels smooth, I wouldn't worry about it. Just look at how rough the ports are from the factory, they're like the lunar landscape, lol.
 
I've read that 320 is the way to go?
If you've never done it before, 320 finishing up at 4-600 works just fine. I start more aggressively at about 180 and work up. Before you start though, how proud are the sleeves? If they're only a few thousands, I'd just leave 'em be.
 
Alright, more shop time means more questions! What is the red stuff that looks to be coming out from underneath the valve guides? Is this indicating something that needs to be replaced?

Can I find somewhere a list of all these o rings and gaskets in this kit I got from Mike's? Will everything be used in a top end rebuild? Along a similar line, should the rocker shaft seals be replaced?

I put the new valve stem seals on, pushed them on as much as I could, and this one seems a bit crooked. Is this normal?

Thanks in advance!
 

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What is the red stuff that looks to be coming out from underneath the valve guides? Is this indicating something that needs to be replaced?
Looks like red RTV. Not sure why it's there as guides are a press fit. Just remove all of it and press on.
should the rocker shaft seals be replaced?
The shaft's themselves don't have seals. There's a seal for the bushing that goes into the shaft oil passageway. Here's a hard fast rule of seals.... If it requires tearing the engine down to replace it, replace it while the engines tore down.
I put the new valve stem seals on, pushed them on as much as I could, and this one seems a bit crooked. Is this normal?
Not normal. I'd pull it back off and investigate.
 
Yes, that one valve guide seal wasn't seated right. If you pull it off and look at the guide, you'll see a groove machined in it. Then look inside the seal and you'll see a "lip" or ridge of rubber that should snap into that groove on the guide. Twisting it some as you push it on may help get it to "snap" into place.

I'm not sure what that red stuff is you are seeing around the guides. As Jim said, they are a press fit into the head, but they do have an o-ring on them too. But, that o-ring is originally not a red one. That would indicate it's silicone. There are some original silicone (red) o-rings used but as far as I know, this isn't one of them. If the guides are tight in the head, I wouldn't mess with them, just clean the red "swarf" off.
 
Got the head built up today! Currently working on cleaning the gasket surface on the case up...

How clean does this need to be? I know the ideal answer is "completely," but there's some real tough spots. However, everything feels smooth. I've attached a couple pictures of how it looks now.
 

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That looks pretty good. Before assembly, I do a final wipe down of all gasket surfaces with lacquer thinner. This removes all traces of oil, even body oil from your hands, and dries quickly without leaving any residue behind. It may even get any little gasket remnants off for you. Wet a Q-tip down with it and scrub the questionable spots. You can get small pint cans of it in the paint department of most hardware stores and that little can should last you for years.
 
Thanks for the reply! Here's another question:

It's getting pretty cold where I live, colder than I normally ride in. Would it be alright for the bike to sit after being rebuilt until warmer months to break it in, or what would be the best way to handle this situation?
 
It would probably be fine but you might want to kick it over multiple times to get some oil pumped up into the topend.
 
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