Friday, November 25, 2016

A Few New Things...

It seemed like a good idea at the time

So, it with winter coming I decided that I would get a few things done while the weather was still warm enough to work.  I had not been riding too much and finally I had a chance to take care of a few things.  Since the rebuild of the carbs, I noticed that I was not getting quite the high-end performance I had expected with a nagging miss around 3000rpm.

Fix the obvious

Points and condenser

I started by replacing the points and condenser.  Not a bad idea.  The old ones were so shot I could see them arc across the points themselves to the arm that holds the points.  Hey, that may have been the miss.  Or not.   It certainly helped and thanks to the magic points adjustment tool ($24 well spent) I went for keeping with mechanical timing.  I guess I just like the thought as opposed to an electronic system that just flat dies by the road with absolutely no options.  Still not satisfied I tried to balance the carbs with my home made an manometer.  What is that?

Detour: The manometer from hell..for $6

To measure your vacuum on the carbs and balance them you can spend a lot and get a fancy set of gauge that giggle and bounce making it really hard to see if things are steady.  That costs around $60.  Or you can spend $6 and get a more accurate gauge.   Attach a 4 foot length of 1x2 perpendicular between a couple 3ft lengths of 2x4 so it sticks up in the air and the base is stable enough so it does not fall over.  buy 10 ft of 1/4 in clear plastic aquarium hose. and loop it from the top of the 1x2 back up to the top.  secure it gently with zip ties.  Fill it with some automatic tranny fluid so you have about a foot in each column of tubing.  Secure the top.  You might have to use a couple short lengths of fuel line to keep the upper ends of the tubing from kinking as you bring them down to the bike.  now when the bike runs, the carb drawing the most vacuum will pull some of that ATF up its side of the loop.  Instead of trying to read a little bouncing dial you have a nice stable column of fluid that probably moves one inch for every 1/32 inch giggle on a needle.  It is really precise.  Pure physics.

Fuel flow...or not.

So, again, that helped but not cured.  Time to check fuel flow because it seemed as though one carb might be starving.  Pulled the petcocks and found them to be in poor shape.  Replaced one outright ($45) when dumbo broke it while tightening it.  I will not tell that story. Ever.  New screens, one new petcock...what could be a better time to look a the tank.

Tank sealing 101

I looked in the tank and realized that years ago someone had sealed it and that seal was shot.  Gross junk.  So, here's what I did.

  • Get a jar of naval jelly ($6) 
  • Gallon of acetone ($10)
  • Box of baking soda.  Don't use your spouse's from the kitchen.  Get you own. (Tip for a 35yr marriage #43)
  • An 8oz can of POR-15 49216 tank sealer ($13)
  •  a short length 18in or so of brass chain.  small stuff, that figure 8 type.
  • 2 rubber stoppers that fit the petcocks...BAD MEMORY..I thing they are 1/2 inch or so.  Measure yourself. ($3) 
  • A "pick up tool"
  • Air Compressor
  • Hair Dryer or Shop Vac 
  • Enough protective gear for a chemical attack.
  • A couple dark nights with no neighbors around.

Flush the tank with water.  Add the chain and shake that tank with water to bust up all the loose old sealer and rust.  Repeat until dawn or the only thing left in the tank is whatever sealer is still sticking.  
Add the acetone and put the gas cap on.  shake it every few hours for a day or so.  The old sealer is turning into sludge.   Drain that mess back into the Acetone can and Flush the tank with water.  If convinced its all out of there, pull out the chain.

Now, add the Naval Jelly and warm water.  Half tank. slosh it to break up the jelly.  This is galvanizing the metal with an acid.  fill it to the top and let is set for a day.   Drain it, flush and fill with water and baking soda.  Now the acid is neutralized, and your driveway is the cleanest it has been in years.

Drain it, flush it with water like crazy and blow it out with Compressed Air.  Dry with hairdryer or shop vac blowing into the tank.

Follow directions on POR-15.  You've already cleaned and prepped the tank just dandy.  The directions are shake it, pour it. tape off the opening for the gas cap and start methodically turning tand tilting that tank.  The BMW has a 6 gallon tank and you are going to get about 2-3 oz of extra sealer when you drain it finally.  It is a thin, thin coat.  Let that sucker dry for 96 hours or whatever.  Don't rush it.  So for $35 it is clean, galvanized and then sealed with aluminum powder suspended in a fuel proof paint.  Yipee, it will last forever and so much nicer that that gooey plastic sealer that was in there before.  Yellow mung.

Back to the Petcocks and some other thoughts.

Reinstalled the screens and petcocks plus...a new set of in-line filters ($10) and have great fuel flow.  Still a little missy, so time to re-check floats.  I think they were a little low and might have given it some fuel starvation?  Anyway, it seems better.  Time to do some other checks or just have a pro play with it for an hour and get it right.  I'm pretty happy with the valve clearances and associated noise.  Its been a few years since I checked them - so it might be time before I spend money on a real mechanic.  Something I can do and feel good doing.

Starter problem - not so fast!  It's the cable, stupid.

So I was doing some checks, balancing the carbs by letting them carry the idle individually until they would just die after a few kicks.  Really using the starter a lot.  All of a sudden, I got the chattering sound of the bendix not fully engaging the flywheel to the point where the sucker would get full voltage and turn!..and its not the first time.  A few weeks ago, I changed out my old Bosch for a Chinese knockoff Valeo.  Yeah, I know.  But it was doing this same thing.  Chattering.  It stopped when I put it all back together and the new starter seems okay.  Now its a few weeks later and its doing it again!  Then I hear it.  POP...   I spotted a freaking spark off my negative ground cable!  Until I moved it around I had no idea it had rotted and broken by one of the connectors.  Probably 1/3 of the wire gone.  Well.  Replaced the ground wire and it starts like a champ.  Obviously that old Bosch was not the problem and now I have a spare starter handy for the day the former democracy demonstrators turned laborers at Tienanmen Industries Starter Factory #7 located near an old above ground nuke test site in the Western Deserts fails me.  What do those people want?  A 12 hour day and  a 6 day week?

So that's almost the end of the story

Thursday, August 20, 2015

32mm or 40mm Jet Needle

You may find yourself in this position - I did.   I'm rebuilding my 32mm bing carbs and having ordered a new set of jet needles I noticed that they were a little bit shorter than what was installed.

It turns out there was a simple shipping error from a very reputable and super company who I called and immediately set about to get me fixed.

In the process of researching however, I noted a lack of simple information about these needles.

Length of Main Jet Needle

Pre 05/1983 Bing 32mm is 61mm long

40mm is 55mm long

For what it's worth.

Friday, November 18, 2011

Still Strong.

I really haven't been the greatest blogger on this the last few years. I think as a result a lot of things going on in the real world and in my own world. But I wanted to bring you up to date on what's going on the old BMW. She still running strong and riding great.Despite having over 98,000 miles on her she still turns heads and gets people waving and I hope a few people envious. Considering how little I spent  I have had such joy writing that motorcycle is I cannot express.

Going to begin to summarize in a few blogs saw the work of those happen to the bike last few years and I'll do my best to get some pictures up on the web also.

Removing the Luggage Racks

In an effort to clean up the bikes lines, I removed the luggage racks. I really have not been using them and they just  continued kind of mess up the lines of motorcycle.

Wednesday, January 30, 2008

Repairing the Kill Switch Lever

When I bought the bike the kill switch was functioning but very...very sensitive. As well the end of the plastic thumb lever was broken off. Initially I rebuilt the broken piece using a plastic epoxy putty. The switch had become finicky and rather than experience one of those embarrassing and dangerous "surprise engine kills" while going down the road and inadvertently touching the kill switch with a winter glove while adjusting the mirror stalk -does it sound like this may have happened to me? - I took the switch apart and did some maintenance to it. I'll blog that separately. So, the plastic thumb part was weakened as I attempted to trouble shoot the switch. I cut a trough into the back side of the switch and fitted in a piece of 6d finishing nail.

Covered it up with epoxy and Viola...good for another 30 years.

Sunday, January 27, 2008

Installing the Thunderchild Voltage Regulator and Diode Board

My voltage regulator and diode board arrived. Also included were the little studs to mount the board to the engine case. Big improvement over the 30year old rubber ones. One was all but gone, another cracked through and the diode board was holding on for dear life by two rubber mounts and one of the grounding wires was about cut through from apparently being pinched by the case during a reassembly some time ago. See pic

Note that the old board was in 'pretty good' shape considering this is the original board, not the upgraded one done a couple of years later. Those are identified by a gray stripe across them.

It is VERY tight in the back of the case to get these studs in place. But Thunderchild has made a great work around. The bold shaft is cut for a metric Allen key..about a 4 mm. Bend one of your old keys at a 45 degree angle to be able to place it under the starter on the lower right stud.

Thread your washer and nut OVER the Allen key.

Place the stud through the case and then place the allen key in the stud allen key hole. Picture shows how the key with the nut and washer is placed in the allen key hole.

This allows you to BEGIN threading the washer and nut. DO NOT thread completely. Just get it started and pull out the Allen key. If you don't you end up with the allen key jammed against the starter. Just use is as a temproary holder so you don't drop the washer or nut.

Here is the allen key on the right Upper nut. The Right Lower is the hard to reach one.

Finally, placed a little hose material behind the voltage regulator as padding. What the heck.

Installing the Front Tire - Brake Checks

Installed the front tire and did brake adjustments. While the tire and wheel were off at ADVENTURE BMW in Chesapeake Virginia, I took the time to do some preservation work on the forks and brake calipers.