engine overhaul

[franck]

I would welcome any comments on when to start a thinking of a refurb of the engine.  The bike BMW K75C 1985 – mileage 66 000,  I renovated just about every thing except stripping the engine. After 3 months the bike runs well and the engine sounds “sweet” (I am 50% deaf so I will take my friends word on that one).  There is quite a lot of “smoke” if the bike has not run for a few days especially if left on the side stand – I understand this is normal - after a good run exhaust is normal.
Before the final reassembly I did a compression test – the engine was cold
Results in psi 145 – 150 – 135  with oil introduced into the cylinders 150 – 165 – 140.
I ride the bike most days and I don’t want to start stripping the engine until it is necessary.   My question is, given the mileage age and compression test – is it worth planning an overhaul?  Or can I clock up some more miles?
Many years ago I learnt  the hard way  “If it works – leave it alone”

[rbm]

At 66K, the engine is almost broken in.  No overhaul is required at this time.  The early K-bikes did not have pinned rings so the engine was more likely to smoke if left on the side stand.  Mine does that too and it is embarrassing at times.  The cure is to lean the bike slightly to the right for 15 - 30 seconds when you turn the engine off, before putting it on the side stand.  That allows the oil to drain so less leaks past the rings.

[franck]

Robert:  Thanks for the tip.  Yes it can be embarrassing - one morning I almost filled the boulangerie with exhaust.  I now park up round the corner and always leave the bike on the main stand. 
regards Frank

[billday]

Look around Motobrick, you won't find any threads on engine rebuild. These motors are pretty bulletproof inside.

It can help to refurbish the air/fuel intake department -- throttle bodies, injectors, fuel lines, and the rubber parts that go above and below the throttle bodies. You can find good threads on that topic here.

[Chaos]

I've learned the trick to dealing with smoking start ups is to get the bike in position for a clean get a way BEFORE starting the engine.  That why you can take off immediately and not have to deal with all the dweebs choking and gagging in their espressos.

[Chaos]

Look around Motobrick, you won't find any threads on engine rebuild. These motors are pretty bulletproof inside.

Also, in the event of major failure, it is usually more cost effective to find a good used engine.  Because the engines are so indestructible there are plenty to choose from and the prices range from about $200-$400.

[riots100]

Look around Motobrick, you won't find any threads on engine rebuild. These motors are pretty bulletproof inside..

This is true, there isn't much information on engine rebuilding.  So when I had to partially rebuild mine, I was mostly flying solo. (http://www.motobrick.com/index.php/topic,7661.msg57782.html#msg57782)  I had a bent #3 connecting rod caused by hydrolock due to the accumulation of excess fuel in the cylinder because of a defective/leaking Fuel Pump Regulator that was allowing additional fuel up the vacuum line.

The engine is working great now BTW.

[Laitch]

This is true, there isn't much information on engine rebuilding.  So when I had to partially rebuild mine, I was mostly flying solo. (http://www.motobrick.com/index.php/topic,7661.msg57782.html#msg57782)
The engine is working great now BTW.

That's good news, riots. Consider returning to that thread and wrapping things up there so anyone who discovers that thread will know how it worked out.

[F14CRAZY]

For whatever reason I don't have the sidestand smoke issue unless it's on the sidestand for a couple weeks. Fine for a few hours, overnight and weekends. I figure I have around 135k miles on the engine.

[The Dude]

For whatever reason I don't have the sidestand smoke issue unless it's on the sidestand for a couple weeks. Fine for a few hours, overnight and weekends. I figure I have around 135k miles on the engine.

+1