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Well, my bike was ALMOST done...

M

mymindsok

Guest
Hi Guys!

As you probably all know, I declared the of my RS done, complete a couple of weeks ago but as fate would have it, the electrical gremlin came back with a vengeance last week. Let me explain...

<a href="http://s177.photobucket.com/albums/w238/kenwhitehawk/83%20R-100RS/?action=view&current=81R-100RS041-1.jpg" target="_blank"><img src="http://i177.photobucket.com/albums/w238/kenwhitehawk/83%20R-100RS/th_81R-100RS041-1.jpg" border="0" alt="Photobucket" ></a>

In my last installment, I had taken the RS up to Auburn, CA for the 49er Rally as a shake down run and during that trip, the ignition began cutting unexpectedly. My friend Pat and I checked the bike over again, cleaning up some connections that I missed and after that, the bike performed flawlessly for maybe 200 miles. I was convinced that the electrical crap had been put to rest once and for all.

Last Wed Pat and I made a date for me to be at his place in Concord, to balance my wheels, so leaving at about 9:AM, I rolled the 72 miles down 101 to Rt 37 and then RT 180 without incident. Once we got the bike into the garage and cooled off, it took longer to remove the rear wheel than it did to balance then and Pat was nice enough to use a couple of his special vintage wheel weights on my bike. Nice!

<a href="http://s177.photobucket.com/albums/w238/kenwhitehawk/83%20R-100RS/?action=view&current=81R-100RS107.jpg" target="_blank"><img src="http://i177.photobucket.com/albums/w238/kenwhitehawk/83%20R-100RS/th_81R-100RS107.jpg" border="0" alt="Photobucket" ></a>


Getting done early was a good thing. I had gotten a late start from home because of the rain in Santa Rosa and I still wanted to hit Key Kraft in SF for two sets of bag keys, plus I also wanted to shop for a pair of riding boots.Therefore, with the real work done, we hit the road for the City.

Needless to say, after that build-up, 20 minutes of fairly hard riding left me with my bike, standing by the side of the road. Again... At first we thought that it was fuel starvation but after a system check the bike started and ran perfectly. Ok, we're off! The next time it quit on me, we removed the tank and checked the ICU's connection. A little more fiddling and the bike ran again, so we thought that we needed to replace the ICU, so we made a Bonzi run into Castro Valley to hopefully buy a new module. To make a long story short, no one had one. Not one the local auto parts stores or at the Buggy Shop. Finally, out of desperation we called and rode over to Recommended Service, owned by Dave Gardner. He had the part and it was only $229.95! Dave's been around Airheads forever and when we were discussing problem and Dave asked:

“When the bike cuts out, does it backfire?
Yup... It sure does.
Does this happen when the bikes hot?
Uh huh...
When the bike cools down, does it run ok again?
Uh... Yeah! Pulls like a freight train!
Well, I'd suggest that you replace the Bean Can. The ICU is probably fine.
Huh?
Yep.. Seen it a million times. The can gets hot and then it becomes intermittent.

While Dave was perfectly willing to go along with our reasoning and sell me a new ICU for $229.95 if I wanted one but a new Bean Can costs $500+!! I had to sit down for a minute... I thought: "What if the problem turns out to be the module, even after we swapped in a new BC? Or even worse, what if I install a new ICU and then discovered that it was the Bean Can at 10PM, half way to the Chief Joseph Rally in Oregon, on a back road, in a rain storm?"

Pat, Dave and I threw ideas around for a little while but in the end, I ducked into the office and handed my Master Card over to Dave's wife, before leaving with a brand new bean can Ignition and a few rubber parts that I needed.

We got back to Pats garage about 7:00PM and immediately pulled the tank and the front cover off, yanked out the plugs and began preparing to install the new ignition by disconnecting the ground and setting the engine at TDC. Then, working with one of us on each side of the engine, we unplugged and pulled out the old BC and installed the new one. When we checked for spark, there wasn't any...

<a href="http://s177.photobucket.com/albums/w238/kenwhitehawk/83%20R-100RS/?action=view&current=81R-100RS059.jpg" target="_blank"><img src="http://i177.photobucket.com/albums/w238/kenwhitehawk/83%20R-100RS/th_81R-100RS059.jpg" border="0" alt="Photobucket" ></a>

Now get this... Over the course of the next 20 hours we tried everything we could think of several times. We connected the BC, disconnected it, put the old one back in, reconnected everything, disconnected everything again, traced out the wiring, checked for continuity, disconnected and reconnected the ICU, cleaned the contacts,checked battery voltages, amp drops, supply voltages . Pin polarities and grounds Nothing... It was late, we were both tired, I hate doing electrical stuff anyway (I once fried the wiring harness in my R-75 trying to install a fuse.) so I was almost happy to toss in the towel and hit the hay.

Thursday morning, after going through the whole list again... Twice... We opted to try replacing the ICU next and luckily, we found a brand new one at a VW restoration shop for a bargain basement price, came home, installed the part and... Nothing...

This time we stopped and thought the situation through again and realized that the only thing that we hadn't examined carefully was the plug that connects the Bean Can to the ICU and when we pulled on it to get a better look, the plug's case came away in Pat's hand, leaving the wires with the connector clips waving in the air. When we examined the clips, the barbs that hold then into the plug were flat and unmarked, they had never been properly installed at the factory. Thats a new one. Then we examined the original Bean Can and noticed that the top screwd had been removed and installed using a too small screw driver. Pat said: “Someones been in here before. I wonder why?” Well without dwelling on the question, we traced out the wiring, reset the plug's wireing as per the reinterperited diagram plugged everything together and... Nothing...

<a href="http://s177.photobucket.com/albums/w238/kenwhitehawk/83%20R-100RS/?action=view&current=81R-100RS066.jpg" target="_blank"><img src="http://i177.photobucket.com/albums/w238/kenwhitehawk/83%20R-100RS/th_81R-100RS066.jpg" border="0" alt="Photobucket" ></a>

By now, I was 100% frustrated and calculating how much of my money I could recover by parting the bike out, so I told Pat that I was going to go upstairs and lay down on the sofa for a few minutes, while he elected to get on-line. I directed him to Snowbums site. I had worked my sales estimate up North of $4500 when Pat gave a whoop and called me into his office. As it turned out, both our diagram and Snow bums drawing showed the plugs wiring based on polarity but Pat had reassembled it using the diagram pictorially, meaning that the wires ended up reversed. Then it was back down to the torture chamber, where we had the bike running 10 minutes later.

To test things we did another Banzai run, through rush out traffic, out to Key Kraft, on Church Street in Castro. We wanted to make the bike fail 'right then' if it was going to, so we ran across the freeway to the bridge at 80 to 85 MPH and then crossed the bridge, splitting lanes at a crawl all the way and across the City, dealing with more stop and go stuff. The bike ran flawlessly!

After ordering my lock work, we then crawled across SF and had dinner in China Town before Crossing the Golden Gate Bridge and rolling up HWY 101 back to Santa Rosa at high speed, to get and keep the engine hot. I had no problems what-so-ever.

Saturday, I was up early and headed into the city again to pick up my keys and did another 70 to 80 mph trip, combined with an afternoon's worth of city riding, without incident. Therefore, I'm relatively confident that we solved the problem but theres still a question of exactly what problem we actually addressed. Was the bike cutting out because the Bean Can was bad? Pat and I agree that B Cs usually either work or they don't but Dave Gardner's experience is too vast to ignore, so we installed a new one. Was the ICU bad? Maybe. I certainly thought so and the ignition did respond to plugging and then replugging that unit.

OTOH, Pat is entirely convinced that the root of the problem was the faulty plug connecting the BC to the main harness. Probably a $.50 part. Heres his reasoning:

The real key is the fact that we noticed some ginched screws on the Bean Can's case, indicating that the canister had been opened up before. We also kenw that it had not been taken completely apart. That indicates that someone had been poking around in the ignition and judging by the corrosion and dirt on the case, it was some time ago. Also, There was a good reason why the PO parked his bike in his barn, with a full tank of gas and never rode it again.What was it?

We think that the ignition failed the PO in the same manner that it did me and because he was an electrical engineer and also considered himself to be something of a gear head, he tried running down the problem and had no success. How did he miss it? Because the problem was intermittent and was hidden inside of the plug casing. How many times have you traced an electrical to a misassembled plug? Right. Never.

So thats it for a while. The bike has a few new parts, my wallet is a few hundred dollars lighter and the RS is running well enough to land me in jail. I'm learning to use the GPS and I really like having it on board. This coming week I intend to find time to reinstall the lowers, along with some auxiliary LED stop lights to be hidden in the turn signals. Then, I can reinstall the seat lock along with the original ignition tumbler and start cleaning the bike up a little more.

I just hope I'm done hard-core wrenching for a while...

<a href="http://s177.photobucket.com/albums/w238/kenwhitehawk/83%20R-100RS/?action=view&current=81R-100RS105.jpg" target="_blank"><img src="http://i177.photobucket.com/albums/w238/kenwhitehawk/83%20R-100RS/th_81R-100RS105.jpg" border="0" alt="Photobucket" ></a>
 
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I hope you have it solved! Sounds like you do. The wiring systems are the most likely spot to feel the effects of thirty years of age, vibration and heat. Then again, your problem was with a new one.

I think the connection points of the wiring system are one of the spots that get compromised by the reality of assembly lines. They have to able to attach things quickly and efficiently (multi-wire connectors, quick connect devices, etc.). There are lots of opportunities for problems, some which show themselves immediately and some reveal themselves after a few years of heat and vibration. There is a substantial difference in the wire connections of the older bikes verses the newer models. The newer ones usually work right and can be fixed or improved without too much trouble, as long as you know where to look for trouble. Thanks for sharing about something that should be checked before we plunk down money for an expensive part that may not need to be replaced.
 
What a head-scratcher! Glad you got it fixed. Neat looking RS, too.
BTW, I have a friend with an '83 RS and wants to mount his Zumo. I see you have a gps. Could you post a more detailed photo? I saw your pix on photobucket, but can't see where the mounting gizmo attaches.
Could save a bunch of work.
Thanks, Jeff
 
Generally when bikes reach the 20 year old threshold and are ridden somewhat on a regular basis U will be fixing or correcting worn parts or systems as they fail or wear out due to use or age. The old saying, it's the nature of the beast, applies. One month it's the can, next week wheel bearings, after that it is the leaning sidestand, leaking petcocks, bent rim, dry rotted rubber, leaking gaskets or seals, corroded wires, bad switches or relays; on and on. The rider of an older bike; his work is never really done. U gotta a nice bike, thx for sharing.
 
have you removed the ing. module under the tank, cleaned and renued the white heat-sink paste?
 
Generally when bikes reach the 20 year old threshold and are ridden somewhat on a regular basis U will be fixing or correcting worn parts or systems as they fail or wear out due to use or age. The old saying, it's the nature of the beast, applies. One month it's the can, next week wheel bearings...Snip

Well, hopefully I have ducked that bullet.

After I bought the bike, my friend and I spent the next month or so rebuilding and servicing every system on the scooter.

<a href="http://s177.photobucket.com/albums/w238/kenwhitehawk/83%20R-100RS/?action=view&current=LATESTFULLFILE002-4.jpg" target="_blank"><img src="http://i177.photobucket.com/albums/w238/kenwhitehawk/83%20R-100RS/th_LATESTFULLFILE002-4.jpg" border="0" alt="Photobucket" ></a>

<a href="http://s177.photobucket.com/albums/w238/kenwhitehawk/83%20R-100RS/?action=view&current=LATESTFULLFILE005-3.jpg" target="_blank"><img src="http://i177.photobucket.com/albums/w238/kenwhitehawk/83%20R-100RS/th_LATESTFULLFILE005-3.jpg" border="0" alt="Photobucket" ></a>

So far we've done the following:

Installed a Toaster Tan Billet top clamp
Installed a Telefix fork brace
Rebuillt the front end with new progressive HD springs
Installed new steering head races and bearings
Serviced the wheel bearings
new tires and tubes
SS Brake lines
rebuilt the brake master cylinder
New ICU
New Bean Can
Cleaned up carbs
new air filter
new clutch assy (The whole shootin match!)
serviced the swing arm bearings
Serviced rear wheel bearings
fresh fluids everywhere
Cleaned all electrical connections
Fresh headlamp bulbs
All new cables including the clutch and speedo
repainted bag mounts and rear rack
New Progressive HD shocks
Brand new seat from Siebenrock
LED stop lamps hidden in the turn signals
New accessory plug
Installed a Brown side stand
New Repro Hoske mufflers
Lots of new rubber parts
Painted the wheels
Plus: Lots and lots of hours spent cleaning

Did we forget anything?

This coming Winter I'll probably tear the bike down, weld in a frame stiffening kit, repaint the frame, have the pipes coated and put the bike back together. That should do it! :thumb

PS: One of the things that allowed us to do so much, so quickly, was because I had a bunch of R-100RS and RT parts laying around. That way, there was allways something that could be prepped, painted, cleaned or rebuilt in advance or while we were waiting to other parts to show up. Also, I was lucky enough to have a stash of brand new parts on the shelves that wern't dedicated to my other project, so we could just grab parts as we needed em.

I learned a long time ago that "It's all about parts. You either have em or you need em but in the end, working on motorcycles is all about parts."
 
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