Honda-SOHC

Hope someone can teach me on this. Is it true that some valves are special and are not supposed to be lapped and if you do, you will do more harm than good? Second question: what is it precisely, that causes valves to wear?

Additional question to this, what would make the valves special (do I have them?  )

Do you mean re face?
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Yes! Autocorrect on a smartphone…

To the best of my knowledge standard Honda valves have no "coating" although the tips may be stellite.
The valve seating area on the valve you show does look to be pockmarked and as these faces are not supposed to be machines only lapped you may have a problem getting a decent seal

Thanks for your quick thoughts Bryanj. I am not very worried for a bad seal as there where no problems (to my knowledge) with it before I opened up the engine. I still have to lap the valves with compound so that might also make it better.

Any advice on how to clean the valves/take of the carbon?

Cheers,
Ruben

Hi all,

After rebuilding and painting the engine to replace primary chain + rubbers, I am now at the stage of rebuilding and assembling the cilinder head.

I am planning to (lightly, they are in pretty good shape) lap the valves and replace the valve stem seals. I have bought the lapping compound and the suction cup tool and am looking forward to this job. Before starting on that though I want to properly clean the valves from carbon etc.
I have watched several videos on how to clean the valves and on that basis I started cleaning the first exhaust valve by spinning it in a cordless drill using a scotchbrite pad/brass brush to clean the valve (see picture for the result). After cleaning the first valve I had the feeling there was some sort of coating on the valve. My question;

- have I done irreparable damage to the first valve or can I still use it?
- what is the best way to proceed with the other valves?

Pictures:

1. engine in restoration proces
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2. exhaust valves
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3. inlet valves
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Thanks!
Ruben

Hi all,

I am in the middle of taking my bottom end apart to replace my primary chain + rubbers. Going smooth (so far), making notes and labeling parts, but (i think) after flipping the bottom end over to loosen the bottom case bolts I found something lying on my workbench. I couldn't find where the fiddly part comes from and the manual didn't mention it.

Is it some kind of oil jet?

The situation:
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The part:
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Anyone who recognises it?

Cheers,
Ruben

Thanks for the warm welcome all!

If you change the primary chain(Kawasaki one exactly same and half Honda price) change the primary damper rubbers, there are 8 and not cheap but necessary

@Bryanj, thats is a very good tip! I was already looking at parts on this website: https://honda4parts.nl/product_info.php?products_id=40

Primary chain = 70 euro
Dampening rubber = 5 euro

Seems like good prices, is the Kawasaki one cheaper?

Thanks!
Ruben