Author Topic: Cb750 K1 exhaust valve removal help!  (Read 613 times)

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Offline MadDogCanada

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Cb750 K1 exhaust valve removal help!
« on: August 13, 2017, 07:06:37 PM »
Stripping k1 engine to replace casing.
Any tips on removing exhaust valves and guides, without special tool. 
Intake valves slipped right out,  exhaust side are all in...

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cb750 K2:Fraken bike project
CB750C 1980. resto project

Offline 754

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Re: Cb750 K1 exhaust valve removal help!
« Reply #1 on: November 04, 2017, 07:59:20 PM »
Do not five them up without removing the  carbon. 
 The tool is simple to make with a lathe.
 Do they have a snapring?
 There is a trick if they do that can make it easier.
 Did you warm the head for the "intakes pushed right out"?
« Last Edit: November 04, 2017, 08:02:06 PM by 754 »
Maker of the WELDLESS 750 Frame Kit
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Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way

Offline BPellerine

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Re: Cb750 K1 exhaust valve removal help!
« Reply #2 on: November 05, 2017, 04:11:47 AM »
some have used a bolt of the right size with a nut or 2 ground down so it will pass through as the guide goes out,heat the head up it will be easier .
1978 CB 750K ard and webers
another anfob

Offline MRieck

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Re: Cb750 K1 exhaust valve removal help!
« Reply #3 on: November 05, 2017, 06:36:23 AM »
 The valve stem tips have flared....you need to rotate the valve with some fine sandpaper wrapped around the stem tip until the valve drops out. Purchase a 6.6mm valve guide drift. You have to bead blast the ports ( as mentioned earlier) or you will drag carbon through the guide bore. After heating the head to about 250F drive the guides out from the bottom.
 I have removed and replaced at least 50 lbs of guides over the years in this manner.
http://www.cylinderheadsupply.com/kl2266.html
 This drift is nicely made and reasonably priced
Owner of the "Million Dollar CB"

Offline 754

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Re: Cb750 K1 exhaust valve removal help!
« Reply #4 on: November 05, 2017, 08:05:17 AM »
The key to the driver is a slight undercut, so that you do not flare the top of the guide or get the driver stuck in the guide. A hand ground one can easily hurt the guide.
 I hate dragging carbon thru the head, so I often drill the top of the guide mostly thru, then break top of guide off at snap ring.. Then. Remove into the port if there is room.
 Then you are not dragging carbon thru the guide bore.
Maker of the WELDLESS 750 Frame Kit
dodogas99@gmail.com
Kelowna B.C.       Canada

My next bike will be a ..ANFOB.....

It's All part of the ADVENTURE...

73 836cc.. Green, had it for 3 decades!!
Lost quite a few CB 750's along the way