Testing ICU - R65LS '82

[Red_Hen]

Hi Guys,

I have an electrical problem that I think points to the bean can.  Bike has a new coil, new plug wires & caps & Wehrle unit was replaced with something Rick Jones sells.  Valves are set correctly and carbs are balanced.  Battery is new.  Fuel is fresh.

Leading up to today, bike would run and then suddenly conk out as if someone turned off the key.  It would later re-start - I thought it had to do with the bike being cold.  

Rode her yesterday @ 50 miles w/out incident.  Today was a different story.  Went for a haircut and when I left,  got on the bike, turned the key to "on" and no electrical.  Turned key off and then on again and I had lights on dash.  She started and as I was riding off, she ran like cold with same scenario as above.  I got on the highway and bike started hesitating and popping and then she died.  I tried starting her and she ran for a minute and then conked out.  After that - nada.  The only telling sign was when I switched on the key I heard a popping sound.

Called my neighbor who picked me and bike up.  Bike now in garage.  As stated, I've gone through everything except the bean can - I do have a new sensor, thanks to another member on this forum.  Looks like it may be time to overhaul the can but before I do, wondering what the process is to diagnose?

From all I've read the sensors usually act up in hot weather - well that's definitely not the case here in MN today - in the low 50's.

[Red_Hen]

Quick Update - just went to try & start bike and she starts!

Are these the telling signs of a Hall sensor on the way out or could it be something else?

[montmil]

Ken, Just to keep everyone on the same page, the ICU (Ignition Control Unit) is the solid state bit attached to the heat sink underneath the tank. The ITU (Ignition Trigger Unit) is ye old bean can.

You've probably already confirmed continuity of the three 22ga. wires out of the ITU. If they get pinched between the webs during a refit of the engine front cover, the occasional or total failure can be a result. Undortunately for me, they tested good with the engine off but a partially cut wire continued to cause grief. Look for a smashed portion of the wires sheathing.

Hall senders can suffer heat related failures. Modern automobiles use thing things in several different locations as 'crankshaft triggers'. My wife's cadillac DTS suffered an intermittent engine failure caused by this very issue and it was heat related Thank you, warranty!

Luck to you.

[Red_Hen]

Hi Monte and greetings to your lovely bride!

Was thinking the symptoms are more like a pinched wire and Yes, I was referring to the bean can - will disconnect battery and check wires - very symptomatic of a short!  Thanks!

[Bob_Roller]

I had a similar issue with my '81 R65 about 20 years ago .

The engine would just quit like you turned the key, or kill switch off .

I was doing alot of night riding then and I would lose the entire electrical system when this happened .

At the time, I  was told to go through the entire electrical system and check all the connectors and 'pins ' for corroson and security in the connectors .

I did that, really didn't find anything out of the ordinary, but it hasn't come back in 20 years, well except two weeks ago, when the camshaft stopped turning !!!!!!!!!

[Red_Hen]

Thanks Bob and interested to find out the rest of the story on your motor.

I had a similar issue with a Honda SL125 - I'd be riding along and bang - bike would die - in that scenario, culprit was corrosion on the kill switch - checked my kill switch and wires look pristine!  

After disconnecting battery, removed front shield and no pinched wires and wire coming out of bean is new, when Judson Cycle got it running for me - thinking not bean can but a short.  Being 32 years old, some of the wires that connect to the alternator are brittle - really not sure where short is but the behavior sure points to a shorted wire "somewhere."  Since I've been through all the wires under the tank and checked the kill switch, will re-focus under the shield - there's a tech session this coming Saturday so will see if some of the senior airheads might be able to help me trace it.  

Bike NOW starts up and runs fine!  Dies on the road, starts in the garage - isn't that the way it works?

[Red_Hen]

I've read some threads on dying bean cans - it seems like they don't suddenly die.  Thinking I've had some warning signs - bike suddenly conks out while riding - but has happened when bike was on the colder side - like first 5 miles of riding.  

While riding today it just started dying like someone turned off the ignition and given it doesn't seem to be the kill switch and that I've gone through all the wires and replace coil & ICU my gut says the hall sensor is on it's way out.  

Is there a way to test?  Or since I already have a new Hall Sensor maybe I'll disassemble and replace the sensor for good measure and peace of mind.

Here's a link on rebuilding the BC

http://www.gunsmoke.com/motorcycling/r100gs/auto_advance/index.html

Thanks again,

Ken

[davidpdx]

I had the same kind of problem on a Honda 350 and it turned out to be the ignition switch. Too many keys on my key ring swinging back and forth for 30,000 miles had worn out the little contacts in the switch. Expensive to replace at the time but fixed the problem. Good luck and let us know what you figure out.

[Red_Hen]

Gonna overhaul the 'ol bean can - want to minimize my chances of getting stuck on a busy highway!  No fun.  

[k_enn]

I had something similar several years ago.  I would be riding on the highway, the tach dropped to zero, the engine popped and backfired, then the idiot lights flashed as the bike went dead.  It did not want to start at first, but after sitting a few minutes it re-started, and I made it the 10 miles home.  I thought it was just a fluke.  The next day, it happened again.  Figuring I would try the "three strikes, you'r out" rule, I continued to use it and the problem has not reoccurred for several years.  Never did figure out what it was.  I wish you luck on the troubleshooting.


k_enn

[Red_Hen]

Wow - bean can disassembly reminds me of peeling an onion!

Wondering how we're gonna separate the (2) pieces of metal so we can drill out the old hall sensor and attach the new one - wondering if someone here could shed light on getting to this part of the Hall Sensor replacement process.  Will the off-white plastic piece easily lift out w/out breaking?  Delicate job for sure!

Innards look pretty good - wondering what you use to clean & lubricate.

[montmil]

I did not drill out the rivets securing the Hall sensor to its mount. I ground off the rivets and then it was a simple pin punch and hammer to knock out the rivets.

[Red_Hen]

I did not drill out the rivets securing the Hall sensor to its mount. I ground off the rivets and then it was a simple pin punch and hammer to knock out the rivets.

Thanks, Monte - how did you get access to the second rivet as its blocked by the second plate shown in my picture - put another way, how did you remove the plastic piece & separate the lower metal piece beneath the plate that holds the hall sensor?

[Red_Hen]

I contacted Daryl Richman and he forwarded me his pictorial on overhauling his bean can - a good article to bookmark for future reference!

http://www.bmwr65.org/cgi-bin/yabb2/YaBB.pl?num=1262401521/0

[montmil]

Ken, I've been scratching my head trying to remember a plastic shield inside my bean-o cans. Friend and Cannonball'er Daryl's photos confirmed it for me... No plastic shields inside my ITUs.

Perhaps yours may be a later model.