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My 1974 R90/6 never-ending project, with plenty of pics.

Regrettably, my schedule is already full this weekend. I have an early gig next friday, so saturday April 10th would be the next possible day.
 
Nathan, the gig is on.

Please PM driving directions. I kinda remember but let's not take chances.
 
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Well, today was the gig, indeed.

No pictures, sorry.

We addressed the flywheel by filing smooth any burs/bumps on the teeth. Although it's pure speculation what caused the initial problem, we believe that the two starters broke because of a binding-up of the starter teeth when engaging the flywheel.

We go it to turn over smoothly.

Then, we noticed the timing was way off. Once eyeballed into place and checked and rechecked, we tried it again.

It started and performed a-ok. I asked for a percent confidence level, and he reported it at 100%. To avoid any jinxing, my confidence level is set at 78%.

After woodnsteel left, I re-assembled the bike, and started it up again.

:thumb

I'm still a little hesitant when it's time to hit the button, but it's now working. I will properly set the timing and points when I have time. (I'm riding my R75 in the mean time.)
 
I should fly you out here so you can work on my bikes.

Pretty soon you'll know all the tips and tricks!
 
Actually, I just accepted an internship for this summer in California.. Bringing one of my airheads, for sure.

If you've got some free time, we could meet up again.
 
...just another grab'n at straws question:

this isn't an 8-tooth vs 9-tooth Bosch starter issues, is it?

Other things that make me go hmmmm:

  1. discarded cardboard ring washer on the back the the solenoid. These are actually spacers. Note Greg Bender's Boasch starter rebuild link
  2. Missing or too many washers on the non-business end of the bendix
  3. Bent solenoid actuator lever (its mounting is not handed)
  4. Bent 'axle' for the actuator lever
  5. Slop in the starter mounting hole on the engine case or smaller diameter bolts than OEM?

You do come up with the damnedest puzzles. Hope you guys got it fixed.
 
I told Nathan that it is best to try one thing at a time, to make 1 change per operation so that you know when you hit pay dirt. Un-fortunately we were running short of un-broken starters so I suggested that we ought to try a couple of things together. Between dressing the flywheel teeth and swapping out the starter relay, we were able to get the bike started without wrecking another starter.

When turning on the fuel and trying to start the motor, the starter would make an awful noise. This as opposed to rolling the motor without ignition, either with the spark plugs in or out. Under the non-firing conditions, the starter sounded like it ought to. That's how we discovered the timing to be off toward the advanced. How it go to be that way is a mystery. We also discovered that the point set had failed in that the little plastic insulator that seperates the condensor wire from the base plate had broken. It was a fluke that the thing would even fire.

Here's the deal. These airheads will run and run and run, even when there are things gone wrong. What I learned here with Nathan is that when bike goes bad, it might be more than one parameter. That, and never leave home without your "Doctor Bag".
 
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Nathan, I decided against loaning you my point setting tool. I just can't stand the thought of needing it and not having it on hand. I will, however, send you the point cam from a dis-assembled advance unit that you can use to set your points correctly without the entire mechanism in the way. Knowing you are an engineering student, it might be a fun challenge to take the measurements and make one for yourself. I seem to remember that you had a lathe there in your shop. Hell, you might even be able to make a few bucks turning out extras and selling them.

Send me your mailing address and I'll get the point cam in the mail to you.
 
Well, I've got 3 lathes, and a mill, and a shaper, and...

:thumb

If you don't even want to send me anything, I can probably just take mine apart and make my own tool.
 
I can probably just take mine apart and make my own tool.

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:thumb

..and I statically and dynamically timed it, too. Good to go.
 
Three months in California on my R75/6 came and went. The remaining week before school started back up, I gathered all my new parts in my shop and went to work.

(Pictures to come.)

For my R90, I purchased and installed;
-Spiegler SS brake line.
-Fehling S bars from Huckys. The Clubmans I had on it for a while lost their charm in stop-and-go traffic.
-Those rubber rings that go around the gauges.
-Clutch cable.
-Brake cable.
-Throttle cables.
-Associated rubber bits.
-WestCo battery. My $50 WalMart battery just doesn't cut it any more.
-Front brake switch.

On Saturday, I got it inspected (where I was able to drool over this bike in person) and licensed.

During the 70 miles of errands on that day, the bike just cruised along at 5000 rpm in 5th gear, approaching 95mph indicated (I wonder how accurate that is).

Things are going good, and there's only a minor hiccup. The right carb is leakin'. Kicked it a few times, didn't fix it. I lifted the needle several times and it seemed to shut off the fuel each time. I figured the float was saturated and sank, not allowing the needle to seal, so I replaced the float first (with a brand new one). It didn't stop leaking, so I stole a needle from my R75 (which didn't leak on that bike) and installed it with the brand new float but the carb is still leaking. I could probably go for a brand new needle, but I was additionally wondering if the seat that the needle contacts is wonky/replaceable.

Edit; what I was referring to as "the needle" is #42.
 
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Things are going good, and there's only a minor hiccup. The right carb is leakin'. Kicked it a few times, didn't fix it. I lifted the needle several times and it seemed to shut off the fuel each time. I figured the float was saturated and sank, not allowing the needle to seal, so I replaced the float first (with a brand new one). It didn't stop leaking, so I stole a needle from my R75 (which didn't leak on that bike) and installed it with the brand new float but the carb is still leaking. I could probably go for a brand new needle, but I was additionally wondering if the seat that the needle contacts is wonky/replaceable.

Edit; what I was referring to as "the needle" is #42.

If the fuel flow stopped when you lifted the float, that indicates the needle and seat are OK. Also suggests that your float isn't adjusted to the right height. Start bending ...
 
You've checked for a cracked flat bowl overflow tube, right?

Check that brass tube carefully (You might need a magnifying glass.) If it's cracked, theres no fix and it has to be replaced.

Look CLOSE!
 
Well, it stopped leaking. So, I guess it was one of those problems that fixes itself if you don't pay attention? :ha

The rain stopped, so I went for a nice ride today. This picture defines southern Missouri in my mind. Creek on the right, little cliff on the left. Shade all around.

20100910004.jpg


..and I couldn't just stick to asphalt. I did about 30 miles of dirt/gravel.

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20100910011.jpg
 
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