Seized 81 GL1100

[CYBORG]

The cylinders look good, Just make sure the valve seats are not pitted or they will have to be reground or replaced. Be very careful cleaning the gasket material off. Its really easy to scratch up the aluminum heads. I used single edged razor blades and scotch brite pads.

Spoiler alert. Seats have a special coating on them, and can not be ground

[robin1731]

The cylinders look good, Just make sure the valve seats are not pitted or they will have to be reground or replaced. Be very careful cleaning the gasket material off. Its really easy to scratch up the aluminum heads. I used single edged razor blades and scotch brite pads.

Spoiler alert. Seats have a special coating on them, and can not be ground

The valves are coated. The seats are not. They can be cut. Valves cannot be ground.

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[CYBORG]

I stand corrected

[Perfikt]

So should I try to lap the seat with the old valve to clean it up? Or am I going to need a machine shop?

Edit: here's the seat after scotchbrite.

20180819_201811.jpg (106.62 KiB) Viewed 265 times

Second edit: have any of you guys used the roloc bristle discs for cleaning the heads? They're nylon or something, internet says they're good for aluminum.

[OCR]

Lapping will not fix that, it will need to be cut slightly and then the valve lapped to match.

[Perfikt]

Lapping will not fix that, it will need to be cut slightly and then the valve lapped to match.

Is that a me job? Or a shop job?

[robin1731]

Lapping will not fix that, it will need to be cut slightly and then the valve lapped to match.

Is that a me job? Or a shop job?

Machine shop. Have them check valve stem to valve guide clearance while they are there. Do all the seats in both heads. You could lap the valves yourself if you have the tools and know how. Or they can do it. Just be sure to tell them not to grind the valves.

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[Perfikt]

That's what I figured after looking it up.

There's someone with an ad in Portland that says they do bead blasting, change guides, change stem seals and grind the valves all for $380 (I think) for the set. Is that someone from here?

I haven't pulled the second head yet, if I take it to a machine shop out here is there any info I need to give them?

Edit: https://m.ebay.com/itm/HONDA-GOLD-WING- ... 1187187898 Ebay link

[robin1731]

1. Guides rarely need to be replaced. Sometimes they do but it is fairly rare.
2. If the guy says he is grinding valves that is a shop to avoid. You do not grind valves on these. They have a stellite coating on them. Grind it off and the valves can wear out pretty quickly.

I just rebuilt some heads for rcmatt. You can ask him what he thought of the work. Did much of the same things that guy says he does. Yours would need the seat cut, his did not. His did not need guides. I've replaced guides in one set of heads in the 15 sets or so I've rebuilt. Cast iron valve guides hold up very well in stock engines.

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[Perfikt]

1. Guides rarely need to be replaced. Sometimes they do but it is fairly rare.
2. If the guy says he is grinding valves that is a shop to avoid. You do not grind valves on these. They have a stellite coating on them. Grind it off and the valves can wear out pretty quickly.

I just rebuilt some heads for rcmatt. You can ask him what he thought of the work. Did much of the same things that guy says he does. Yours would need the seat cut, his did not. His did not need guides. I've replaced guides in one set of heads in the 15 sets or so I've rebuilt. Cast iron valve guides hold up very well in stock engines.

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The valve grinding might have been a mistake on my side, I meant valve seats.

This is all excellent information, thank you very much. I found a local machine shop that might be able to help, says he needs to see the heads first. I'll try toget them down to him this week.

On a side note, would it be prudent to get all the seats ground? Or just the one(s) that show wear?

[robin1731]

No, the ad says they grind the valves.

Yes, get all the seats cut.

[rcmatt007]

Robin did excellent work for me.... including putting a helicoil into the head bolt hole tat the PO stripped out about 39 years ago

[robin1731]

Robin did excellent work for me.... including putting a helicoil into the head bolt hole tat the PO stripped out about 39 years ago

hhhmmmmmm, the PO.

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[rcmatt007]

Always blame the PO

[chewy999]

Always blame the PO

But how long can you own a bike and still blame a PO?