Valve guide replacement

[jacksdad]

I'm restoring a XS650C thats been stood for years, came from Daytona Beach, one of the exhaust valves was seized solid, I had to drift it out, I've just lapped in a new valve, and then found the guide has split
How do I replace the guide?

 

[Signal]

The Clymer manual has a reasonable description of the process and gives the temperature to warm the head to (in an oven200-400 deg F, 93-204 deg C). When I did this the guides come out with minimal effort.
Before you remove the guide, bead blast the combustion chamber side and clean to remove any built up on the guide that could score the valve guide housing when you drive it out.

 

[jacksdad]

Ok thanks, I've fitted new valve stem oil seals on the other 3 (typical this was the last one!) Do they need to come off again?
Anychance I can draw out the guide with a long bolt nuts and spacer?

 

[jacksdad]

Oil seals came right off again, no probs. The heating temp is a bit vague, 90-200 deg C is a very wide range! Is it best to go for the lower or higher temp?

 

[Signal]

Its so long ago that I can't remember what temp the oven was set to. Given the temperatures these bikes run at I think you would be safe at the high end of the range. You could try a lower temp, I do remember the guides came out very easily. Keep in mind the adage "Be kind and use a big hammer".

So far as using long bolts and spacer; there is always more than one way of doing something, I would not do it that way, others might. Using the method I described there is little risk of damaging the head.

 

[jacksdad]

Well, heated the head up, the alloy head was 120C and the cast iron guide was 98C using my laser temp thing (very handy tool and only £17 from Lidl!)
Put a steel rod onto the guide, gave it a smart hit with a large hammer....and smashed the guide
It didn't budge at all, just fell apart...it is cracked in 2 places along its length, I thought it would fall out...
Now getting a better drift made and will try again...not too confident anymore

 

[Signal]

I did not expect that to happen. Could you post some photos , it may give some inspiration on what to do if the new drift doesn’t work.

 

[Bucko]

hiya mate,you can buy the proper tool from yambits,i think theyre about eight quid!