Engine Overhaul

[Nice_One_Son]

Morning all,

A question for you,

My 65 has been stood for approx 9 years in dry storage, prior to that it was used infrequently by the previous owner, so, in the last 15 years or so, hardly any mileage has been accrued.

I am at the point of preparing for engine removal (see pics) should I get the top end overhauled and remove the heads now or wait until the engine is out and then do it?

The manuals suggest doing the top end whilst the engine is still in the frame.

Any chance of guidance and advice please?

[Bengt_Phorqs]

Have you checked the compression first?  Just because a bike has been in storage doesn't mean that a top end job is required.  More likely you will experience some weeping in the various seal points due to a lack of activity.  Check the pushrod seal areas.  Definitely change all of the fluids.  Any milky colored oil in the tranny juice?  This is not uncommon if the bike has been sitting in the weather but you mention "dry" storage.  Condensation can still occur. Pull the tranny off and do a full on shaft clean and lube and check the seals.
 
In my experience most BMW's can go at least 50k minimum before a top end job is required.

[Bob_Roller]

I've got an '81 R65, rumored to be the worst year for valve recession .

I had a 'top end' done at 45,000 miles, the valve faces were quite worn .

If I were you, I'd do a compression test before you take the engine apart .

With the exhaust and intake tubes removed, rotate the engine by the alternator bolt, and take a look at the valve faces when the valve opens .

The cylinder walls are hard metal plated, kind of like chrome, so the cylinder won't be rusted .

Piston rings may be a different story .

I've got 82,000 miles on the 'lower end' , without anything ever being done, still the original rings, with 139 psi in each cylinder on a compression test .

How many miles (kilometers) does the bike have ?

[Lucky_Lou]

If i were you i would pull the heads anyway it wont hurt to re seat the valves (the clearances will need resetting anyway)and check the bores i re honed mine and fitted new rings anyway as i dont want to go back there for a long time even though theres only 30k miles on it, the full gasket kit from your neighbors is only 29.90 including the push rod tube seals i dont think theres much difference doing it on or off the frame piston rings arent that expensive either just go to R65 engine parts on the Motorworks web site ring them first then nip over the fence and pick them up.
Lou

[Nice_One_Son]

Thanks Guys,

I had begun to go down that road, as you can see, the strip down is progressing nicely and as Lou says, I don't want to have to go there for a while.

Thanks again.

Cheers

[steve hawkins]

Just to add a little spice to proceedings - I personally would have done and oil and filter change and then I would have turned her over a few times on the starter, then I would have tried to fire her up.  Perhaps I would have put a few drops of oil down the spark plug hole before I turned her over.  but if she turned over by hand and she was in outwardly good order, and she is, that would have been my route.

How many miles ?  My Cafe Racer had 94,000 miles by the previous owner before I touched her.  

But only to put in different heads and a light rebore (79 model with steel liners)  - I was offered a set of post 81 heads with unleaded seats and since my exhaust threads were knackered....

Steve H

[Nice_One_Son]

She has done 33,000 miles.

When we collected her, the clutch was seized and we tried to "bump" the bike to release it, we could hear the cylinders moving freely in the bores.

I have been told that because the bike has not run for some time a compression test would not work as the valves would not seat properly until the bike has run and warmed up.

The previous owner had no issues with running, when he placed the bike in long term dry storage, he did not follow the recommendations for laying the bike up, however on strip down so far we have not encountered any issues with seized or locked fasteners, the bike seems very sound other then light surface rust.