Topic: Valve guide honing Q? Answer found.

[Don R]

 I bought a cb750 head with new Honda guides already installed and one stuck valve. I replaced that guide but now need to hone it and possibly other ones to fit the new valves. No one around here seems to want to work on a 750 so I ordered a 5.5 mm kibblewhite hone which seems to be the one for use on our bikes.
 I assume you simply hone it with light oil, clean it, check it, hone it, clean it,  check it, until the valve fits cleanly, clean and make sure there is a spec'd minimum of side clearance. Sound correct? 

[grcamna2]

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[Big Jay]

WE use a Sunnen guide hone and hone the guide to fit the Serdi pilot that we will be using to machine the seats.

[MRieck]

WE use a Sunnen guide hone and hone the guide to fit the Serdi pilot that we will be using to machine the seats.

That's the way

[Don R]

Of course that's the best way, possibly making this the next best way. L0L!

[grcamna2]

Of course that's the best way, possibly making this the next best way. L0L!

is the difference between a hardened tool steel valve guide reamer or a small ball hone ?

[RAFster122s]

I thought you had to cut new seats always after replacing a guide.  Is that not correct?

Thus, the response by Big Jay and Mike.

[MRieck]

I thought you had to cut new seats always after replacing a guide.  Is that not correct?

Thus, the response by Big Jay and Mike.

Correct. The valve center line moves after installing a new guide

[grcamna2]

I thought you had to cut new seats always after replacing a guide.  Is that not correct?

Thus, the response by Big Jay and Mike.

Correct. The valve center line moves after installing a new guide

Mike,
What brand valve guides do you use ?

[Big Jay]

http://cbrzone.com/sohc.html

[RAFster122s]

Big Jay,  do you have a similar page or product listing for the CB550?
David

[Don R]

 I'm hoping the other guides and seats were done correctly, it changed hands a couple times before I got it so I can't ask. My plan was to get the valve in, dye the seats and hand lap it in, check the pattern and then call for help if needed. It's for my K0 engine and I don't have a proper cylinder yet anyway.

[BPellerine]

I don't know a lot about this but hondaman says 6.5 reamer and finish hone,now ape sell a 5.5 hone and a 7mm hone,which one ?be nice to know for those of us who don't have the good stuff available to us.bill

[Don R]

 Well, the 5.5 hone is obviously intended for the 5.5 kibblewhite undersize valves and their guides. Pretty useless for stock Honda valve guides. I'm thinking 6.0? 

[Big Jay]

We don't ream guides. Our guides have a high nickel content for wear, and will wipe out most reamers. 

[754]

Easiest  and cheapest for Joe Average... Ball sizing... Should work..

[Don R]

 I don't even know what that is. I see APE lists 5.5 and 7 mm hones.

[754]

You get a precision sized ball, force it thru the hole..done .
If you get the right size ball.

[PeWe]

My ports got even more grinding job when the 5mm conversion kit went in. The guides aligned different and only seat cut was not enough according to the guy that ported it 1983. He smiled when he could do more work on it 33 years later
EDIT: The additional work done was visible before valves went in, closer to the seat and seat itself. More flow  Hopefully better....

[Don R]

 That should flow some air.

[Don R]

It's all here if you can just find it, I ordered a .259 reamer.  And while I was at it I learned to read my micrometer with my glasses on. My exhaust valves measure new spec .259" so they're going to be plenty tight that's 6.58mm for those keeping score.




http://forums.sohc4.net/index.php?topic=127377.0

[Don R]

 The exhaust valve fits nicely, after the reaming. I didn't think the exhaust stem would be slightly smaller, it is. Not pro quality but i'll check the seat with my old neway.