Topic: Weak compression in #2 cylinder

[buffalosabresbrewer]

Im looking at another bike for sale locally. He says it runs but has weak compression in the #2 cylinder.

What might i be looking at here in terms of repair?
Its a 1978 750 super sport. Is the super sport another name for the "F" or am I just missing something? Thanks.

[TwoTired]

It's an F bike and probably needs the top end replaced.  Pay accordingly, or keep shopping.

[buffalosabresbrewer]

When you say the top end needs to be replaced this involves what exactly?

[martino1972]

that involves:
-take engine out frame
-remove cylinder head
-get new valve guides installed
-valves regrinded or replaced
-reassemble

[TwoTired]

that involves:
-take engine out frame
-remove cylinder head
-get new valve guides installed
-valves regrinded or replaced
-reassemble

Some will say that is not enough.  That an other-than-short-term-repair requires a K style head and pistons, too.

There has been a a LOT of discussion on his forum about the 77-78 750 F model foibles.

[buffalosabresbrewer]

-get new valve guides installed
-valves regrinded or replaced
About how much do you think that might cost?

K style head and pistons
Would these be hard to find?

[750goes]

could also be just a crappy valve adjustment causing the low compression...but worst case scenario is an engine out complete rebuild .... how much money you want to invest or minimise on ??

[buffalosabresbrewer]

Well of course I want to minimize the amount of money spend but a grand pretty easily.