Top End Help

[hudson]

So you guys are saying to turn the crankshaft nut to turn the flywheel, correct? I have read you can do either do that method or put your bike in the highest gear, elevate the rear wheel and turn in normal travel direction - both accomplish the same thing: the valves open and close, the pistons go in and out, the flywheel turns and you look for the 'OT" marking on the flywheel.

The Top End Manual from OAK (a well-known beemer wrench) & Snowbum's Tech article recommends the rear wheel method. Is there a reason or advantage of turning the crankshaft nut instead of the rear wheel method? I am not challenging anyone, I just want to do it the best way. Much appreciated guys!

UPDATE - I called the BMW shop and described the problem. They think it has to do with the valve seats since they had to recut seats in the heads and it not creating enough clearance.

[SteveD]

Either is ok. You must turn the wheel so that the crankshaft does one revolution, not the wheel.
If you've done the left side, then move to tdc on the right by ensuring you get the OT in the middle of the timing hole. Just one revolution of the crankshaft. The pushrods should be loose and turn easily.edit..that is, the push rods on the side you want to be at tdc on compression.

[hudson]

Thanks for the clarification. I wasn't clear in my original post. I meant the crankshaft turned one revolution as I turned the back wheel and watched the markings to reach "OT" after one full rotation. Sorry not saying what I meant. No wonder there was confusion. I know what I meant, but I didn't explain it well. Thanks everyone...

[Garnet]

I think what we are all worried about is that you are adjusting the valves on the wrong side of the bike. When the flywheel is at OT both pistons are at TDC. One is between the exhaust and intake stroke and the other side is at the top of the compresion stroke.

Follow George's method to make sure that you start on the correct side. Trust me, this has caught out more than one person around here.

We don't want to see you pull it all apart for no reason. Your BMW shop would have had to cut the seats WAY WAY down too far to not be able to get clearnace.

[Major Softie]

Although the rear wheel works just fine for turning the crank, it IS really easy to miss the mark going by when doing that, so I would guess that is what happened and you just inadvertently turned the crankshaft two revolutions.

Lets hope that's all it is.

[Motorhead]

there is a learning curve in all new methods of work

[Dave Backmarker]

Hudson,
In Garnet's post above he is worried if you started with the first side on compression or in between exhaust and intake. Take a look at the section in Oak's manual titled, "Determining Left or Right Side - Which is on compression stroke..." When I rebuilt my R90S last year I went through these steps twice to make SURE I knew which cylinder was on the compression stroke.

While this is a great procedure, I can't figure why the rockers on the first side were fine and the other side are so tight. To that point, Kurt suggested above that maybe the pushrods are not seated in the lifters. You mentioned that the pushrods protruded about an inch? Was this the same on both sides?

DaveM
1975 R90S, 2000 R1100RT

[hudson]

Hey everyonbe - I appreciate your help and suggestions. It ended up being the height of the valve seat. Everything is fixed and back together. again - thanks for the tips on OTC. I torqued the stud nuts to 26lbs and then retorqued this morning. HOWEVER...........

This seems like a stupid problem, but my cylinder heads on both sides weep oil where the gasket is sandwiched between the cover and the head.. I put new cover gaskets on dry and torqued the center cap nut to spec around 18.5 lbs wuth blue locktite and the two small nuts on each side to very snug. but the bottom lips both weep oil. What gives? These are new covers BTW, but that shouldn't make a difference.

[Dave Backmarker]

Hudson,
There are no stupid questions. At the risk of incurring derision from my fellow airheads, I use a tiny bit of grease on both sides of the valve cover gaskets. In my defense, I learned this trick from a machinist back in the early '70's. Whenever I'm working with a low temp gasket surface that I know will be taken apart and put back together repeatedly, I use grease. Also, Ted Porter's Beemershop offers very nice gray gaskets (silicone?) that have worked well. And, I'm sure you tightened the valve cover nuts in something approaching a pattern to ensure the cover isn't slightly twisted.

DaveM
1975 R90S, 2000 R1100RT

[Duane Ausherman]

For assembly one doesn't need to consider the position of anything. Just put it together. It is the adjustment of the valves that care about the position of the crank/flywheel etc.