Go Back   Horizons Unlimited - The HUBB > Technical, Bike forums > BMW Tech
BMW Tech BMW Tech Forum - For Questions specific and of interest to BMW riders only.
Photo by George Guille, It's going to be a long 300km... Bolivian Amazon

I haven't been everywhere...
but it's on my list!


Photo by George Guille
It's going to be a long 300km...
Bolivian Amazon



Like Tree1Likes

Reply
 
LinkBack Thread Tools Display Modes
  #31  
Old 19 May 2014
Registered Users
HUBB regular
 
Join Date: Aug 2007
Posts: 29
Well I did order a new ICU when I ordered the coil a couple weeks ago. I'll try to check that tonight.
Reply With Quote
  #32  
Old 22 May 2014
Registered Users
Veteran HUBBer
 
Join Date: Jul 2002
Location: Oxfordshire, UK
Posts: 173
I had a similar failure a couple of weeks ago. At first i thought the coils were at fault, as there was a huge crack. So i changed that. Still no spark. Then i did some multimeter testing and guessed that the ICU was faulty. Changed that to the latest version, and got a spark. The bike started but ran rough. It wouldn't restart once warm. I remembered reading somewhere that a bad voltage regulator could cause that, so i changed it (from the high output version back to the standard). It then started and runs perfectly.

The coils that cracked and the regulator were only a couple of years old.

And then last week a friend's R80 G/S did exactly the same. He traced the fault to the ICU, fitted my old ICU (the one that i thought had broken) and now it run perfectly again.

Airhead electrics are a dark art. My friend is an engineering professor, but even so, still found it all quite mysterious.
Reply With Quote
  #33  
Old 22 May 2014
Registered Users
Veteran HUBBer
 
Join Date: Jul 2002
Location: Oxfordshire, UK
Posts: 173
Yet another cracked Bosch ignition coil.

Attached Thumbnails
BMW R100GS electrical problem-borl2wjccae_uy7.jpg  

Reply With Quote
  #34  
Old 22 May 2014
Registered Users
HUBB regular
 
Join Date: Aug 2007
Posts: 29
Quote:
Originally Posted by Roboyobo View Post
I had a similar failure a couple of weeks ago. At first i thought the coils were at fault, as there was a huge crack. So i changed that. Still no spark. Then i did some multimeter testing and guessed that the ICU was faulty. Changed that to the latest version, and got a spark. The bike started but ran rough. It wouldn't restart once warm. I remembered reading somewhere that a bad voltage regulator could cause that, so i changed it (from the high output version back to the standard). It then started and runs perfectly.

The coils that cracked and the regulator were only a couple of years old.

And then last week a friend's R80 G/S did exactly the same. He traced the fault to the ICU, fitted my old ICU (the one that i thought had broken) and now it run perfectly again.

Airhead electrics are a dark art. My friend is an engineering professor, but even so, still found it all quite mysterious.
Mine has spark (and even more spark now with the new upgraded ICU that shocked me while holding the plug by the cap as I found out a couple days ago) but still won't run. I'm going to check the compression this weekend and if that's good then I guess it's a timing issue.
Reply With Quote
  #35  
Old 31 May 2014
Registered Users
Veteran HUBBer
 
Join Date: May 2008
Location: SW France
Posts: 304
Would be interested to know if you've solved the problem.
Reply With Quote
  #36  
Old 5 Jun 2014
Registered Users
HUBB regular
 
Join Date: Aug 2007
Posts: 29
No, I'm going to check the compression soon. I have a tester, I just have to read up on how to do it. I guess just ground the plug to the cylinder, open the throttle and crank it.
Reply With Quote
  #37  
Old 6 Jun 2014
Registered Users
Veteran HUBBer
 
Join Date: May 2008
Location: SW France
Posts: 304
That should do it. If it's low squirt a little oil into the cylinder and re-run. If it improves it implies rings rather than valves.
Reply With Quote
  #38  
Old 27 Jun 2014
Registered Users
HUBB regular
 
Join Date: Aug 2007
Posts: 29
Did the compression check last night and I got 75 psi on the right cylinder and 80 on the left. I popped a carb off and squirted a little starter fluid in the manifold and it wouldn't even fire. I have replaced the coil & ICU and I can see the plug sparking so I'm thinking it has to be out of time, right? I'll look into checking this.

Anybody have a spare bean can laying around that I can borrow?
Reply With Quote
  #39  
Old 27 Jun 2014
AliBaba's Avatar
Registered Users
Veteran HUBBer
 
Join Date: Apr 2001
Location: Norway
Posts: 1,379
Quote:
Originally Posted by Drumboy View Post
Did the compression check last night and I got 75 psi on the right cylinder and 80 on the left. I popped a carb off and squirted a little starter fluid in the manifold and it wouldn't even fire. I have replaced the coil & ICU and I can see the plug sparking so I'm thinking it has to be out of time, right? I'll look into checking this.

Anybody have a spare bean can laying around that I can borrow?
The timing has to be very wrong if it's not able to ignite starter-fluid! On the first page in this thread I've described how to check timing with a volt-meter.

It's harder to ignite under compression. I would have tried starter-liquid with the carbs still on the bike and with the throttle closed.
Worn plug-cables will give the same symptoms, you should also check the ground-wire for the ECU (separate wire that goes to the left bolt for the upper engine-cover). Have you changed the plugs?
Reply With Quote
  #40  
Old 27 Jun 2014
Registered Users
HUBB regular
 
Join Date: Aug 2007
Posts: 29
Quote:
Originally Posted by AliBaba View Post
The timing has to be very wrong if it's not able to ignite starter-fluid! On the first page in this thread I've described how to check timing with a volt-meter.

It's harder to ignite under compression. I would have tried starter-liquid with the carbs still on the bike and with the throttle closed.
Worn plug-cables will give the same symptoms, you should also check the ground-wire for the ECU (separate wire that goes to the left bolt for the upper engine-cover). Have you changed the plugs?
I've also tried squirting starter fluid into the airbox a few times with no luck. That's why I tried with the carb off.

Both plug cables are registering 5kOhms and I have changed the plugs. I'll check the ECU ground wire and timing soon.
Reply With Quote
  #41  
Old 27 Jun 2014
Registered Users
HUBB regular
 
Join Date: Aug 2007
Posts: 29
Based on the instructions in the Clymer for testing the electrical components I think that I could possibly have a bad connection between the ignition switch (key) and the on/off selector but I'd like to test that before going through the wiring harness. It has an aftermarket enduro computer on it with the key attached so I'm not sure where it's wired in. Could I run a jumper from the battery to the green wire on the coil to gaurantee that a good 12V is supplied?
Reply With Quote
  #42  
Old 27 Jun 2014
AliBaba's Avatar
Registered Users
Veteran HUBBer
 
Join Date: Apr 2001
Location: Norway
Posts: 1,379
Quote:
Originally Posted by Drumboy View Post
Based on the instructions in the Clymer for testing the electrical components I think that I could possibly have a bad connection between the ignition switch (key) and the on/off selector but I'd like to test that before going through the wiring harness. It has an aftermarket enduro computer on it with they key attached so I'm not sure where it's wired in. Could I run a jumper from the battery to the green wire on the coil to gaurantee that a good 12V is supplied?
For test purposes: Yes
Reply With Quote
  #43  
Old 27 Jun 2014
AliBaba's Avatar
Registered Users
Veteran HUBBer
 
Join Date: Apr 2001
Location: Norway
Posts: 1,379
When you try to connect the green wire directly to the battery it will also power up the ICU (and more). Some ICU's turn off after a while (30sec?) when the engine is not running. So you have to connect the wire directly before you attempt to start.
When doing this remember that you might have to remove the wire to stop the engine.
Reply With Quote
  #44  
Old 27 Jun 2014
Registered Users
HUBB regular
 
Join Date: Aug 2007
Posts: 29
Should I remove the green wire and hook the jumper up to the coil's spade or just attach it to the connector? Can I use a thin wire or will the power going through require a thicker wire? My jumpers are really thin.
Reply With Quote
  #45  
Old 27 Jun 2014
AliBaba's Avatar
Registered Users
Veteran HUBBer
 
Join Date: Apr 2001
Location: Norway
Posts: 1,379
Quote:
Originally Posted by Drumboy View Post
Should I remove the green wire and hook the jumper up to the coil's spade or just attach it to the connector? Can I use a thin wire or will the power going through require a thicker wire? My jumpers are really thin.
If you leave the green wire in place you will also power up the ICU which might be a good thing. If it starts with the green wire in place you can try to remove it to see if it still starts.

Most wires will work. If the wire is to thin it will be hot, but then you can use 2 or 3 in parallel.
Reply With Quote
Reply


Currently Active Users Viewing This Thread: 1 (0 Registered Users and/or Members and 1 guests)
 

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On


Similar Threads
Thread Thread Starter Forum Replies Last Post
'97 TB3 electrical problem tackle Yamaha Tech 4 17 Mar 2010 20:08
bandit 400 gsf electrical problem bandit400 Suzuki Tech 0 3 Aug 2009 20:53
Electrical Problem !! big t Yamaha Tech 29 11 Apr 2008 05:39
yet another electrical problem magyver Yamaha Tech 15 2 Nov 2007 01:02
XR400 electrical problem colsan1 Honda Tech 2 14 Feb 2007 14:27

 
 

Announcements

Thinking about traveling? Not sure about the whole thing? Watch the HU Achievable Dream Video Trailers and then get ALL the information you need to get inspired and learn how to travel anywhere in the world!

Have YOU ever wondered who has ridden around the world? We did too - and now here's the list of Circumnavigators!
Check it out now
, and add your information if we didn't find you.

Next HU Eventscalendar

HU Event and other updates on the HUBB Forum "Traveller's Advisories" thread.
ALL Dates subject to change.

2024:

Add yourself to the Updates List for each event!

Questions about an event? Ask here

HUBBUK: info

See all event details

 
World's most listened to Adventure Motorbike Show!
Check the RAW segments; Grant, your HU host is on every month!
Episodes below to listen to while you, err, pretend to do something or other...

2020 Edition of Chris Scott's Adventure Motorcycling Handbook.

2020 Edition of Chris Scott's Adventure Motorcycling Handbook.

"Ultimate global guide for red-blooded bikers planning overseas exploration. Covers choice & preparation of best bike, shipping overseas, baggage design, riding techniques, travel health, visas, documentation, safety and useful addresses." Recommended. (Grant)



Ripcord Rescue Travel Insurance.

Ripcord Rescue Travel Insurance™ combines into a single integrated program the best evacuation and rescue with the premier travel insurance coverages designed for adventurers.

Led by special operations veterans, Stanford Medicine affiliated physicians, paramedics and other travel experts, Ripcord is perfect for adventure seekers, climbers, skiers, sports enthusiasts, hunters, international travelers, humanitarian efforts, expeditions and more.

Ripcord travel protection is now available for ALL nationalities, and travel is covered on motorcycles of all sizes!


 

What others say about HU...

"This site is the BIBLE for international bike travelers." Greg, Australia

"Thank you! The web site, The travels, The insight, The inspiration, Everything, just thanks." Colin, UK

"My friend and I are planning a trip from Singapore to England... We found (the HU) site invaluable as an aid to planning and have based a lot of our purchases (bikes, riding gear, etc.) on what we have learned from this site." Phil, Australia

"I for one always had an adventurous spirit, but you and Susan lit the fire for my trip and I'll be forever grateful for what you two do to inspire others to just do it." Brent, USA

"Your website is a mecca of valuable information and the (video) series is informative, entertaining, and inspiring!" Jennifer, Canada

"Your worldwide organisation and events are the Go To places to for all serious touring and aspiring touring bikers." Trevor, South Africa

"This is the answer to all my questions." Haydn, Australia

"Keep going the excellent work you are doing for Horizons Unlimited - I love it!" Thomas, Germany

Lots more comments here!



Five books by Graham Field!

Diaries of a compulsive traveller
by Graham Field
Book, eBook, Audiobook

"A compelling, honest, inspiring and entertaining writing style with a built-in feel-good factor" Get them NOW from the authors' website and Amazon.com, Amazon.ca, Amazon.co.uk.



Back Road Map Books and Backroad GPS Maps for all of Canada - a must have!

New to Horizons Unlimited?

New to motorcycle travelling? New to the HU site? Confused? Too many options? It's really very simple - just 4 easy steps!

Horizons Unlimited was founded in 1997 by Grant and Susan Johnson following their journey around the world on a BMW R80G/S.

Susan and Grant Johnson Read more about Grant & Susan's story

Membership - help keep us going!

Horizons Unlimited is not a big multi-national company, just two people who love motorcycle travel and have grown what started as a hobby in 1997 into a full time job (usually 8-10 hours per day and 7 days a week) and a labour of love. To keep it going and a roof over our heads, we run events all over the world with the help of volunteers; we sell inspirational and informative DVDs; we have a few selected advertisers; and we make a small amount from memberships.

You don't have to be a Member to come to an HU meeting, access the website, or ask questions on the HUBB. What you get for your membership contribution is our sincere gratitude, good karma and knowing that you're helping to keep the motorcycle travel dream alive. Contributing Members and Gold Members do get additional features on the HUBB. Here's a list of all the Member benefits on the HUBB.




All times are GMT +1. The time now is 05:33.