ADVrider

Go Back   ADVrider > Bikes > Old's Cool > Airheads
User Name
Password
Register Inmates Photos Site Rules Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Search this Thread Display Modes
Old 08-04-2010, 08:44 AM   #1
pdulik OP
.
 
Joined: Aug 2010
Location: omaha, nebraska
Oddometer: 3
r90 dyna III ignition problem

i just installed a dyna III electronic ignition on my 1975 r90/6. everything ran perfect for maybe 10 miles until i came to a stop and it died instantly. came to find out the bike is losing spark at idle now. maybe a problem with the coils? everything was working perfectly up until i put the ignition on.
pdulik is offline   Reply With Quote
Old 08-04-2010, 11:57 AM   #2
mykill
odd
 
mykill's Avatar
 
Joined: Feb 2008
Location: Los Angeles
Oddometer: 1,158
retrace

Since you have a history with the bike prior to the Dyna and it always worked fine, then start looking at everthing you touched. Check for power to the coils and quality of connections. Your igniton switch may also be the culprit.
__________________
Never underestimate the laxative properties of motorcycling.
mykill is offline   Reply With Quote
Old 08-04-2010, 05:13 PM   #3
StephenB
G(/)S ... what else!
 
StephenB's Avatar
 
Joined: Aug 2005
Location: Ontario
Oddometer: 2,044
If your coils are new and the correct ones for use with the Dyna III ignition don't read on:

Primary coil resistance has to match the specification of the Dyna, check that. It is possible that 10min with the wrong coil killed the Dyna, when going back to points everything seems normal. If your coils are the original pair of 6V coils, about 35yrs old you could have killed the ignition too. Did you burn points rapidly and was that the reason you installed a Dyna? Signs of too low coil resistance.


What about just simply one of your "new" wires coming loose?
__________________

Some of the above is fact, some is fiction, some is my personal imagination and some is just simple truth. [me]

... i'm not touring around the world, but neither are most of the guys i see running overloaded spam cans ... [bmwblake]

Stephen Bottcher
Ontario, Canada

'72 R75/5 The Blues

www.stephenbottcher.net
StephenB is offline   Reply With Quote
Old 08-05-2010, 11:08 AM   #4
pdulik OP
.
 
Joined: Aug 2010
Location: omaha, nebraska
Oddometer: 3
coils are the original coils. i thought it said that was ok. i didn't go through points often. the reason i put it on was because i heard such good thing about them and i wanted to make the bike more reliable. the low coil resistance is what the guy who installed it was thinking. i guess i'll check the coil resistance and the ignition. one more thing. the bike dies at idle and won't start again for a couple minutes. i don't know what that means either.
pdulik is offline   Reply With Quote
Old 08-05-2010, 02:14 PM   #5
Mandello
Guzzista
 
Joined: Jan 2010
Location: Miami
Oddometer: 155
everything was working perfectly up until i put the ignition on.

I've had both points issues and DYNA ei issues on the road, points never took more than 10 minutes to sort out, the DYNA issue required a tow and overnighting new parts.... unless its for racing i don't see the point(s) in adding a dyna kit :p

AlexM
Mandello is offline   Reply With Quote
Old 08-05-2010, 06:20 PM   #6
StephenB
G(/)S ... what else!
 
StephenB's Avatar
 
Joined: Aug 2005
Location: Ontario
Oddometer: 2,044
Quote:
Originally Posted by pdulik
the bike dies at idle and won't start again for a couple minutes. i don't know what that means either.
That does point to a temperature (time sensitive) issue such as insulation failing inside the coil that start to act when the coil gets warm (heat expansion) and disappear when the coils cool down again (all back to normal). Remember, insulation inside the coil is achieved by using varnish which will age and crack with all those temperature changes over the life of your bike. If the coils are original I strongly recommend to replace them as they are initiating your combustion. If they don't work right, the best electronics won't help either.

This isn't the only possible solution to the problem, but I would not hesiate to replace the 35yr old coils to go with a brandnew electronic ignition.
__________________

Some of the above is fact, some is fiction, some is my personal imagination and some is just simple truth. [me]

... i'm not touring around the world, but neither are most of the guys i see running overloaded spam cans ... [bmwblake]

Stephen Bottcher
Ontario, Canada

'72 R75/5 The Blues

www.stephenbottcher.net
StephenB is offline   Reply With Quote
Old 08-09-2010, 11:58 AM   #7
pdulik OP
.
 
Joined: Aug 2010
Location: omaha, nebraska
Oddometer: 3
well i put the points back in and it's running like a dream again. think i'm going to keep em on the rest of the riding season and worry about it later.
pdulik is offline   Reply With Quote
Old 09-02-2010, 05:32 PM   #8
kraut.burner
Smells güt!
 
kraut.burner's Avatar
 
Joined: Oct 2009
Location: Trenchtown
Oddometer: 460
I did a little research on the Dyna III and found the installation manual. It says the dyna III was designed for use with the stock coils, or coils that have At least THREE OHMS primary resistance.

heres the link:http://www.starracing.com/Star/documents/D35-1.pdf

I too am thinking about using this, and getting new coils as well. Hope this helps!
__________________
04' R1100S- Gone but not forgotten
74' R75/6 Café Classico
R75/6 Café project

kraut.burner is offline   Reply With Quote
Old 02-22-2013, 09:33 PM   #9
flemsmith
lurk
 
Joined: Apr 2006
Location: Apache Junction, Az
Oddometer: 570
I'm confused....

I bought a Dyna III some time ago in prep for a rebuild. So now I'm rebuilding a 78 Moto Guzzi T3, and the instructions I have are exactly the same as the ones you show, except the model number is different D37-1, and it says at least 5 ohms primary resistance. Since I have new coils I've been running with the points that are 3 ohms I'm wondering if I'll end up burning up the output amp if I install it? I may just stick with points for that reason. But the electronics unit looks the same outwardly...would they really have designed a different unit with a lower output for Guzzi's, doesn't make a lotta sense to me.

roy
flemsmith is online now   Reply With Quote
Old 02-23-2013, 08:17 AM   #10
photorider
Gnarly Adventurer
 
photorider's Avatar
 
Joined: Nov 2008
Location: Northern VA and Guatemala
Oddometer: 277
Sensor plate coming loose is a common problem which creates the symptoms you describe (it's how the system is grounded)
photorider is offline   Reply With Quote
Reply

Share

Thread Tools Search this Thread
Search this Thread:

.
Display Modes

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 On

Forum Jump


Times are GMT -7.   It's 09:24 PM.


Powered by vBulletin® Version 3.8.5
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
Copyright ADVrider 2011-2014