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Discussion Starter #1
Here's a pic of my valves (mainly clyinder 4). What would you reccommend I do, aside from replacing them? I wanna try and keep it all together up there, since I don't have the right tools (valve compressor) to do all the tricky stuff.

Can I get away with just sanding the corrosion off?







Thanks

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Le Canuck
My Bike on Flickr

Edited by - Trefmawr on Jul 11 2006 8:56:41 PM
 

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the hardening on those valves has already started to deteriorate, they are probably shot and will need to be replaced. Knowing that that is a cb750 DOHC head you can probably get a complete useable head off ebay for pretty cheap or try www.cb1100f.net.
 

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eeesh. yeah, thats pretty much done. at least from looking at it. and who knows what the seats are looking like, the guides....

j
 

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saw this...probably more useable than what you have and for $45 bucks probably won't hurt the budgie too much, just keep in mind it is all used stuff:

http://cgi.ebay.com/ebaymotors/HOND...ryZ35595QQssPageNameZWDVWQQrdZ1QQcmdZViewItem

this is $49 bucks:

http://cgi.ebay.com/ebaymotors/HOND...2QQihZ010QQcategoryZ35595QQrdZ1QQcmdZViewItem

if you plan on reusing the head core, you are going to need to sand blast it. I have to be honest it looks like that motor spend some time underwater, the cheapest thing to do is to hit up the local MC shops and see if someone has a DOHC 750 or 900F motor lying around, my local shop has two running motors that I could probably get for a couple hundred bucks ready to drop in.
 

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Discussion Starter #5
Yeah I saw the valve lot on ebay a while back and have it saved, but damn! Just got this whole head unit. Oh well it was free...

The top end, cams and shims all look fine though. But can't tell what's inside by what's outside and all that.

Hey Geeto, where you live? Those running engines are looking pretty sweet right now...

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The first thing I would do with that mess is take it apart, completely. Then sand blast the head and the valves and see what you really have. I have salvaged some really horrible looking heads and valves. Honda valves are amazingly good. I bet that after a good cleaning you will be able to cut good sealing surfaces into the seats and lap in the valves.

Ken

AHRMA 412
Vintage racing - old guys on old bikes
 

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I'd have to agree with Ken...I've salvaged some horrible looking heads too. Ditto on the valves...specially the exhaust valves, very tough in most cases.
Go easy with the sand blasting....use some fine sand or glass bead and of course clean the head casting very very good to get all the sand out. I usually clean the valves with a power brush (wire wheel) to prevent roughing up the stem or erroding the valve surface.
JohnnyB
 

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yeah, it can be done. but i think he wants to avoid pulling the valves. just scubbing it off. if youve gone that far, you might as well have someone look at it. someone who knows what theyre doing. pulling the valves is no big deal, but you should use a spring compressor. have a radiused grind putt on the seats, then check the springs. i thnk the idea is to use it the way it is, just clean it off. which i dnt tink is a good idea.

jc
 

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JohnnyB,
I get all warm and fuzzy feeling when you agree with little old me.
Joe, I will agree with you and hope it makes you feel somehow too. If he just wants to use the head as is, I don't think that would be a good idea either. But, as long as the head is coming off then I would throw a good valve job at it or take it apart, clean it up and lap in the valves. All that can be done by anyone with a valve spring compressor and some lapping compound.
Ken

AHRMA 412
Vintage racing - old guys on old bikes
 

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right on. agreed. pretty simple and he could actually do that for very little money. but since its all apart, id spend the $$$ and get the valve job done. its posible he doesn thave to replace springs or valves or guides. just a nice clean up and reassemble. but thats why its worth having someone who can look at it go through it. to put it all together and then have to pull it apart becasue theres a bad spring, or a bad seat or something. looking at it from here, its way too hard to tell.

jc
 

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put the money in it... usually works out that you put more time into a project than money. why waste time on stuff if it is no good. spend the time getting it right. or go buy a new bike.

happy b lated b day jc

layter
matt
 
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