1979 gs750 lower head gasket problem

[1bad79gs750bobber]

I have a 1979 gs750. I am courious if it is a big task to replace/ overhaul the lower head gasket. The gasket is leaking oil severley and it loses all the oil in a few minutes. The gasket is the one that seals the bottom of the jug/cylinder to the caseing any help would be appreciated. I have a doner 77 750 but I really don't want to swap the motors can I do any thing to help make this part stronger if I do rplace it .

[koolaid_kid]

It depends on what you consider a major task. You have to pull the top end, which also means the exhaust and carbs. It's called a cylinder base gasket, just so you know.
The top end means the valve cover, cams, head and cylinder block.
There is some other work to be done while you are in there, BTW.

[1bad79gs750bobber]

That is not to bad what is the other work or at least the minimum amount I should do

[azr]

I'm in the middle of doing the same repair on my 79 850. Is it a "big task"? well I guess that depends on what you consider big. It's probably one of the bigger jobs you could do on the bike aside from a complete tear down or trans rebuild I'm guessing. It doesn't sound like you have much choice other than swap out the engine though. Best thing you can do to "help make this part stronger" is buy OEM gaskets (as I'm told on here) and maybe have the head check for being true. Why don't you want to swap the motors? it would be a less detailed job, as long as the doner is good.

[1bad79gs750bobber]

I really don't want to swap the 77 motor becouse I was hoping to keep it complete on the bike so I had a cruiser bike my 79 is hardtailed and it is not fun to go on long distance trips LOL

[1bad79gs750bobber]

Also I am curious if a 1000-1100 top end can be put on this case I am interested in rebuilding it becouse I want to turbo it so evan if I do swap motors I will still be rebuilding the 79 I can't find to many parts for the 750/850 but I found a website that does alot of 1150 kits and I may upgrade to that

[koolaid_kid]

IDK about swapping the top end, but this is what I would do while you have everything apart:
Check the bores and freshen the rings
Replace the valve seals and lap the valves
Rebuild the cam chain tensioner
Replace the tach drive seals
Replace intake o-rings

The last 3 are not required. However, they are much easier to do while you have everything apart and on your bench, and the overall cost is very low.
As mentioned previously, OEM gaskets are preferred as there have been issues reported with aftermarket gaskets.

[1bad79gs750bobber]

I am courious as to if the 750 top end can be honed and or board to fit 850 pistons or if there is not enough mettle