Pulling heads off for the first time -- help?

[rob650]

I see a lot of comments about folks needing/getting valve work done.  Can you tell just by looking if your valves need attention?  During my valve adjustments, I never saw any abnormal valve gappage.  (gappage?)

I'd be glad to spend some $ in the future for pre-emptive valve work, but I have a deadline of early June for a bike ride to Nevada.

Thanks Thrang.  It's coming apart easily and I've got everything separated and labeled.

Rob Valdez, those pics are great.

[Bob_Roller]

If you have the exhaust off, and the carbs off you can rotate the engine by the allen key bolt that secures the alternator and look at the valves. I did this on replacing the timing chain at about 45,000 miles, and saw that 2/3 's of the valve face worn off!  I have the dreaded '81 model year bike.

[Justin B.]

Normally the first sign is the clearance starting to close up at shorter and shorter intervals.  Never just jump in, loosen the adjuster and adjust the valves - always check the clearance first.  Once this is suspected an inspection like Bob mentioned will be "illuminating".  The edge of the valve will start to get extremely thin, the exhaust valves in my '81 R100 were almost knife-edge thin at 79k miles...

[thrang]

Last time I did the vales on the Bimbo (2002) I replaced them with after market ones from Motobins (think they were black diamonds) and they did about 100k before they began to close so were worth the extra couple of quid they cost especially as I suspect its the seats rather than the valves that are on the way out.

Won't know for sure until I get round to stripping the engine down next winter I'd do it now but  I've not got time to do it with new beemer to knock into shape and the missus moaning about redecorating the front room Dose's anyone actually enjoy decorating?

Ride safe and sane.
Tony.

[Justin B.]

I'm pretty sure that's what was used in the heads on my '81 R100.  I think they are cheaper over here than the OEM valves...

[Rob Valdez 79 R65]

I think my exhaust are black diamond, and the intakes were from R60/5/6, both to get the 8mm stems.
I think the R60 valves were cheaper than b.d for the intakes.

rob650 - thank you.  The pictures are easy, compared to the talent of Bob Grauer.

He installed new everything.  

I suggest you ride your bike for 1000 miles from when you last adjusted them (did you write down your mileage and date from when you adjusted them?), and open the covers and check and see where they are.  If they have closed up .001", make a note of it and close it back up for another 1000 miles.  Repeat.

[rob650]

Rob Valdez, Ill make records of valve adjustments from now on...never did before.

I macked up the right side exhaust threads, so that head is at San Jose BMW getting repaired.  They did say my exhaust valve looks recessed, so Ill save up my dimes for head work later this year.

This has been a fun project for my first time removing the heads.  Now I just gotta screw it all back together and prep for my trip in June.

[Rob Valdez 79 R65]

Try and put on a couple of thousand miles before your trip.

One, after the bike has about 1000 miles on it, you will want to retorque the heads.
Those readings (before retorquing) cannot be depended on for valve recession readings.  Change may have resulted from fasteners loosening and metal expanding/contracting.

Ride another 1000, and check them again.  This will tell you what you have for your trip.

[rob650]

The bike is finally back together this morning.  I took a short trip for about 30 miles and it seems tight.  No oil leaks or unusual behavior.  Started right up after the 2nd crank!  It sounds better and idles well.  It was time and money well spent and I sure learned a lot about these engines.  I'm doing a short ride to the Sierra Nevadas at the end of this week, maybe a 5-700 mile trip.

Thanks everyone for their advice here.  It encouraged me to dive in.  Ill take it apart again in the fall to get the head work done and get my recessed valves taken care of.  Thanks again.

[Justin B.]

After following a very spirited (and often heated) discussion on boxerworks about this it seems that some of the "experts" feel that the initial re-torque and adjustment should be at around 60 miles or so, then a check at 500-600.  I did my initial retorque/adjustment at about 500 miles and nothing blew up, but you never know...

[Rob Valdez 79 R65]

Yeah Justin, I just learned that myself, since writing the above post!

I have to admit to not ever having really sought out Oaks' wisdom (he is the one that was prescribing the 60 mile (or so) check for head bolt torque).  Can't say why.

But I didn't retorque my heads until about 800 miles after my valve job last fall.  Mine didn't blow up, either.  The bolts were all real tight, too.

My intake valves had closed up a smidge, but the exhaust valves gap was just where I had set it.

[rob650]

Got back yesterday from a weekend San Francisco / Reno / Yosemite loop, 800 miles.  The bike ran perfectly!  Not a leaky drop of oil in sight from the new pushrod seals or anywhere else.  I was one happy rider.  I gotta say it again, thanks everybody for their advice.  Now, If I could just get a month off work.....

By the way, zillions of brother bikers up and down Hwy 395.   It was a beautiful weekend for riding.

[Rob Valdez 79 R65]

Yeah, my seals have not leaked since I replaced them, either!

Now, if I could just get 20 years worth of dirt off the block, you could tell...

[Ed Miller]

LOL:  "could" or "would" Rob?  My leaky seals are my excuse for not washing the bike.  It will just get dirty again soon.

[Rob Valdez 79 R65]

I am kind of all or nothing when it comes to this.

I can't do a good enough job to please myself with the engine in the frame, and I have no immediate plans for pulling it, so...