did my first valve adjustment - wasn't too hard... did I do something wrong?
 

Geez, it wasn't nearly as much of a pain in the arse as I'd been led to believe by the OVAD document on IBMWR. Unless I'm totally missing the boat. Here's what I found:

I started out trying to be very picky about matching the feeler gauge "pull feel" between valve pairs. I soon discovered that the play in the whole rocker arm means that things can be slightly differently alighned with each activation of the values, so why bother being so picky I thought?

So I set one side up with a fair degree of pickiness. Then, rotated the engine through TDC a couple of times. Come back and remeasure... things have changed slightly. So, unless you're going to pull off the road after every 4 strokes and reset the valves, being really anal about this is a waste of time.

Once I'd decided this, i used the two gauge method and got things pretty good for each valve pair, using guages just a bit to big and too small to confirm things. Not terribly picky, just took maybe 15 minutes per side.

Then spun the engine around a few times and rechecked. Things still pretty good, so buttoned her up.

With new plugs (Bosch Platinum 4s) and the valve adjustment she started up and ran quite nicely, idled more smoothly. I haven't really taken it out on the road yet.

Question: if it was this easy, was I doing something wrong? :confused: Am I wrong in my assessment of rocker arm play being a dominating/overriding force making very picky valve gapping a waste of time?

That's how I do mine. Get it close and it's good enough for me. There's no way you will get the same exact TDC every time so as long as it's close it should be fine.

People worry about pulling the timing cover off. I found its reinsertion a non-issue with silicon spray.

Yes, you also now need to do a throttle body synch. But you need the Twin Max or other type tool.

Yeah, I know I should do the synch. I'm thinking of building the el cheapo home model that I've seen described here.

One question about that: can the synch be done quickly enough that I don't have to worry about overheating the bike? I'm concerned about ending up running it parked for a long time.

If this is a real concern, I'll end up having the dealer do the synch this time...

I couldn't agree with you more. Some folks swear all that rigamrole in the OVAD document is necessary, but IMHO, it's ridiculous busy-work that makes a simple adjustment needlessly complex.

I have yet for anyone to adequately explain why 3 and 4 thousands variations in shim-adjusted clearances between valves in a high-strung Japanese sport bike motor are perfectable acceptable (heck, the shims typically only come in 2.5 thousandths intervals), but in our tractor motors, we need to get within tolerances an order of magnitude closer using four feeler gauges and 'calibrated drag". Ridiculous.

Two feeler gauges may be a good idea, although BMW doesn't require it in their service manual. With the length of rocker shaft, I doubt even this is necessary. This design is totally unlike the "forked" rocker design that got Honda in trouble with the V4s which did, by later TSB, explicitly require two feeler gauges.

BMW takes about 1/4 a page to describe the process in the shop manual. IMHO, it's just that simple. I've been doing it this way (using the soda straw in the sparkplug hole to find TDC) at 6K intervals for 55K miles now. Takes 30 minutes IF I drink beer about half the time. The bike runs fine.

Ya did great. Ride on.

- Mark

Forgot to say, I have to agree that ridiculous guide and procedure is just that.

I find it much easier to use 4 feeler gauges 2x2 and this seems to give us more more consistant adjustment around here. The best comparison of drag I can offer is take a pen type magnet and attach the feeler gauge to it. Then slide the feeler gauge away and that is about the same resistance you should aim for when adjusting valves. Its not rocket science, but a few tricks do make it a more consistant process.

A cooling fan is not a bad idea, but if you're reasonably well setup, the actual sync may only 30 seconds or so. Just don't fire the bike up and then go find your CarbStix/Twinmax, have a beer, fumble around hooking it up, and THEN start the balance. Be ready to go, and shut it down if you need to do something that will extend it beyond a minute or two.

I just got a Morgan Carbtune and we'll see how this goes. My mercury manometers had developed some small air pockets in the columns that I couldn't get rid of and I didn't want to hassle with mercury again. If I just had a twin, I'd go with the TwinMax, but I've got several inline-fours and a straight-six in my garage.

- Mark

The cheapy sync tool works great and yes it does not take long at all.Try to get 2.5wt forkoil or as light a viscosity as possible.

Yes,

That document is ridiculous. Totally anal and unnecessary.
And this coming from an anal engineer no less.
You could get by being pretty damn crude.
You are totally right in which effects swamp others.
I firmly believe the best bang for the buck is just treating it
like any other valvetrain, but using the two gauge method.
Anything pickier than that and your'e down in the noisefloor.

I'd get a fan, or two, your first time. Maybe your 2nd and 3rd.
After a while, when you can not only do it, but do it quickly because
you have a good seat of the pants feel, you can get buy doing an oilhead w/o one. Goes much faster than airheads, in general.

I'd say you've discovered what we have over time on these valves.
Only you did it yourself, which is a good excercize, and which means you'll understand and remember it permanantly. Can't ask for more than that.

Enjoy,
Roger

Also make sure to sync with the bike at operating temperature. eg> go take a thorough test ride, have all your tools set up for a sync, return to the garage with a warmed up bike and proceed to sync if you want to get it as close as possible.

Guys,

Thanks for all the excellent feedback, I (as always) appreciate it. I feel all warm and fuzzy now.

Roger, I was going to say that I was an "anal engineer" as well. But then I thought better of that expression!

Ride on.

the dumb question
 

Ok, I'm going to ask the dumb question. What IS best or smartest document to read for learning how to adjust the valves and syncing the throttle bodies. I need my 12K service now, and quite frankly I like my dealer, but I REALLY want to learn how to do some of the maintenance.

I reasonably mechanical, but not a mechanic. Any suggestions or links would be appreciated.

Thank you.

Robert

The factory doc is dead simple but presumes existing knowledge.
I'd go with the procedure from a Haynes/Clymer manual.

I'm creeping up on the 48k service (at 46k now). I'll bookmark this thread just to remind myself how easy it 'should' be. I'm still confused about the method for TB sync when using the poor man's manometer.

Re: the dumb question
 

Not sure about being the best... but it is thorough.

http://www.advrider.com/Wisdom/OVADv2.1.pdf

SmileWavy :D

Before doing mine I referenced:

OVADV2.2 from IBMWR

This is the long but amusing one. I reccomend using the description of how to find TDC, and also the description for setting the valve gap. But ignore all the stuff about trying to perfectly match the feeler-guage pull for each pair of valves.

I also referenced:

This nice short one

Start at Step 5. It advises to adjust the rocker arm slack but I don't think this is commonly done.

And also:

this overall oilhead maint manual from IBMWR

Which has a nice brief section on adjusting valves, including the "go/no-go" method of using adjacent-sized feelers to confirm your settings. I think this last one is a good compromise between the first 2.

All in all, they all recommend pretty much the same thing, read them all and you'll have lots of info to go on.

I took off the alternator belt cover but didn't ahve a 16mm socket handy, so I ended up pulling the plugs and turing the motor over with the rear wheel in 6th to find TDC. Worked fine, next time I won't bother pulling the cover, I'll use the wheel.

For the poor man's manometer I have found Dexron ATF to be a great working fluid. Very low viscosity, bright red color, cheap.

VALVE ADJ ..&..
 

RM,

IBMWR.ORG has very good info on adjustments.

http://www.ibmwr.org/r-tech/airheads/index.shtml

If you are not a mechanic here are a few things to watch out for.
Do not get in a hurry. Do not over tighten parts. Be sure you understand the process before you start.

A few tips

1. Use some type of antiseize on the threads of the spark plugs.
The best is what we use on aircraft engines. It is made by Champion, works extreemly well, and could save you the cost of a head. A very small amount accuratly place is good.

2. Most all engines make a bit more power if the valves are set on the loose side. I have actually dino'd this and seen 2 HP increase. The best part is you do not have to worry that you got them to tight as this could cause a valve to burn ( through).
By loose I mean if they call for a 12 thousandths gap....just make it a loose one. You could check your setting with a 14 thousandths....if it fits you are 1 thousandths to wide. Bobby is correct about the feel of a magnet to get the exact as possible distance. But like all have said here it does not need to be to complicated. IN other words a tight 13 thousandths is good if you are looking for 12 thousandths.

I have tried many ideas about finding TDC on the compression stoke. Here is the one that works best & why.

If you use anything that can break off or fall in...that aint cool.
I have a extremely bright flash light ( as in seal team attack type). If I shine it in the plug hole, I can see the top of the piston.
I use a long rounded wooded down about the size of a # 2 pencil. I can actually rest it on the piston crown and turn the engine over with a 17 mm on the crankshaft nut ( the same DIRECTION as it runs) which is under the black cover. I can truly feel when the piston stops its travel at the top. ( you did know that all ICE’s stop for a fraction of a second didn’t you?) You can not get anymore TDC than that. Try it, easy, fast, safe & accurate.

THE four cycles of the engine are Compression ( piston going up& where you want to stop for adjusting purposes) , Power ( plug just fired and piston is going down) , Exhaust ( piston going back up to expel burnt fuel) , Intake ( piston coming back down for fresh air/ fuel charge) . If you spin the engine ( with the socket on the nut under the front cover) it is easy to see this sequence take place…cool too! As the piston comes to the top of the compression stroke you will feel the dowel stop its outward travel. You may need to turn it over a few times to catch the sequence. When you are done though, You will KNOW THAT YOU KNOW and it is a good feeling.

The Twin Max is hard to beat. What is nice is after you adjust idle, if you strap the twin max to your tank ( bag) you can ride and also note the balance at various RPM's. This is very accurate, and your bike will have smoothness you won't believe! More Power as well. You would not adjust the brass screws for anything but idle! I used to not ride to adjust. MAN, let me tell ya, it makes a world of difference.

If a job is worth doing, it is worth doing well!!

PS I tried the alternative plugs as per the ibmwr.org site. The machine ( 99GS) fires off immediately in ALL temps ( no choke needed) , idles very good, gets great milage, and can keep up with the new 1200GS !
I also have a D&D Exhaust ( certified 7.5 hp) and use Royal Purple Race 41 ( 3 HP) in the engine as well as RP through out.

ATE Blue ( used in Indy Cars) gives my brakes good feel. Available a good BMW car store or Bavarian Auto Sport

http://www.************

I need to do the 5k on the BCR, the valves do need adjustment that is obvious, you guys have convinced me to do it myslef, never done one before, RogBro i might be calling you.