High cost of valve seals job ?

Well, you could also try hittin the bottle. A couple of tankful's of Seafoam in the fuel, and then some "Bar’s leaks valve seal oil consumption repair" for the crankcase. Just a thought.....

Sometime it is not the mileage on the bike that matters, but how long it has been sitting around without running. Then the seals will dry out. Run it and you will see how she behaves.

JL

cb900f wrote: The valve seals can be changed without removing the head, but the engine may need to be removed from the frame to give you enough room to get at the seals with the required tools.

There are plenty of reasons why taking the head off might be a good idea but if it was me, with such a low mileage bike, and in the absence of anything to indicate any other problems, I wouldn't bother removing the head at this point.

I agree, the seals can be changed without pulling the head but it's not a simple job. There was a thread here on the subject with photos and links a while back.

The bike is currently torn down to the state in my avatar , I believe I will give it a try assembled , Worse case I have to pull the head , It had been ridden about 400 miles this year , Carbs torn down right now.

It's all very well thinking that it won't need much work with being 40 years old and the very low mileage but how long has it been stood without being turned over.
Valves and seats won't remain clean if just left static and corrosion will form on them at the very least.
The same goes for the bores if you are unlucky.
Oxidisation is generally harder than the base material so that will have been hammered in to the valve and seat contacting surfaces on start up so at the least they will need a light lapping .

This may help. There are other guides kicking around so you may want to search both this site and others...

www.thegsresources.com/_forum/showthread...ng-the-cylinder-head