« previous next »
Pages: [1]   Go Down

Author Topic: Igniters melted on CB650C  (Read 1092 times)

0 Members and 1 Guest are viewing this topic.

iwasaseabee

  • Guest
Igniters melted on CB650C
« on: August 24, 2008, 08:12:41 AM »
What causes the epoxy on the inside of the coil amplifiers to melt on a 81 650?
Logged

Offline MRieck

  • Really Old Timer ...
  • *******
  • Posts: 10,565
  • Big ideas....
Re: Igniters melted on CB650C
« Reply #1 on: August 24, 2008, 08:19:21 AM »
Age, use etc. It's very common on the DOHC Honda's from the early/mid 80's
Logged
Owner of the "Million Dollar CB"

Offline TwoTired

  • Really Old Timer ...
  • *******
  • Posts: 21,805
Re: Igniters melted on CB650C
« Reply #2 on: August 24, 2008, 08:26:15 AM »
The electrolytic capacitors inside fail with low resistance (if not a direct short).  This causes high current to be drawn which is converted to heat, high enough to melt the plastic.

....or so I've heard.
Logged
Lloyd... (SOHC4 #11 Original Mail List)
72 500, 74 550, 75 550K, 75 550F, 76 550F, 77 550F X2, 78 550K, 77 750F X2, 78 750F, 79CX500, 85 700SC, GL1100

Those that learn from history are doomed to repeat it by those that don't learn from history.

Offline tonycb650

  • Enthusiast
  • **
  • Posts: 182
Re: Igniters melted on CB650C
« Reply #3 on: August 24, 2008, 08:38:47 AM »
Mine are also melted on my 650.It seems to run fine. Is this a problem? should i change them? Would it run any better? will this leave me on the side of the road some day?
Logged
80cb650c 80 cm400

Offline mystic_1

  • Really Old Timer ...
  • *******
  • Posts: 6,071
  • 1970 CB750K
Re: Igniters melted on CB650C
« Reply #4 on: August 24, 2008, 09:32:52 AM »
Quote from: tonycb650 on August 24, 2008, 08:38:47 AM
Mine are also melted on my 650.It seems to run fine. Is this a problem? should i change them? Would it run any better? will this leave me on the side of the road some day?


Yes.  Yes.  Maybe. Probably.

:)

mystic_1
Logged
"A ship in harbor is safe, but that is not what ships are built for."
- John Augustus Shedd

My build thread:  http://forums.sohc4.net/index.php?topic=68952.0

Offline TwoTired

  • Really Old Timer ...
  • *******
  • Posts: 21,805
Re: Igniters melted on CB650C
« Reply #5 on: August 24, 2008, 09:53:30 AM »
I'm trying to imagine seeing an electrical component that was melted and thinking it was a good thing and inspiring confidence toward reliability.   ???

Don't think I'd go on long trips under such conditions.  But, I'm just not as adventurous as I used to be.

Cheers,
Logged
Lloyd... (SOHC4 #11 Original Mail List)
72 500, 74 550, 75 550K, 75 550F, 76 550F, 77 550F X2, 78 550K, 77 750F X2, 78 750F, 79CX500, 85 700SC, GL1100

Those that learn from history are doomed to repeat it by those that don't learn from history.

Offline tonycb650

  • Enthusiast
  • **
  • Posts: 182
Re: Igniters melted on CB650C
« Reply #6 on: August 24, 2008, 10:08:29 AM »
thanks alot tt and mystic! >:( now i have something else to fix. :(
Logged
80cb650c 80 cm400

KingCustomCycles.com

  • Guest
Re: Igniters melted on CB650C
« Reply #7 on: August 24, 2008, 10:10:36 AM »
I have an 80 CB650C with melted ignitor boxes.  The epoxy goop ran down onto the airbox and never did get hard again, just sticky.  I thought it was from a PO catching the bike on fire, which he obviously did, but now I wonder.  I spark tested the bike and she has good spark.  On the other hand, my Shadow had pulse generators that appeared perfect and tested fine, yet no spark.  Go figure.
Logged

Offline TwoTired

  • Really Old Timer ...
  • *******
  • Posts: 21,805
Re: Igniters melted on CB650C
« Reply #8 on: August 24, 2008, 10:14:55 AM »
Quote from: tonycb650 on August 24, 2008, 10:08:29 AM
thanks alot tt and mystic! >:( now i have something else to fix. :(

Hey, you don't have to listen to me.  I've never had a 650 SOHC4!   ;)

I did work in electronics for 30 years. ::)

Cheers,
Logged
Lloyd... (SOHC4 #11 Original Mail List)
72 500, 74 550, 75 550K, 75 550F, 76 550F, 77 550F X2, 78 550K, 77 750F X2, 78 750F, 79CX500, 85 700SC, GL1100

Those that learn from history are doomed to repeat it by those that don't learn from history.

Offline tonycb650

  • Enthusiast
  • **
  • Posts: 182
Re: Igniters melted on CB650C
« Reply #9 on: August 24, 2008, 10:29:51 AM »
 I actually figued i needed to replace them, i guess i didnt want to hear it. ;D anyway , i will trust yours and mystics judgement over mine any day! ;D
Logged
80cb650c 80 cm400

martino1972

  • Guest
Re: Igniters melted on CB650C
« Reply #10 on: August 24, 2008, 11:13:27 AM »
are we talking about the cdi unit?????
Logged

Offline tonycb650

  • Enthusiast
  • **
  • Posts: 182
Re: Igniters melted on CB650C
« Reply #11 on: August 24, 2008, 11:48:42 AM »
the part im refering to is called the spark unit. its located under the seat.it actually looks like 2 pieces.
Logged
80cb650c 80 cm400

Offline cb650

  • Old Timer
  • ******
  • Posts: 3,864
Re: Igniters melted on CB650C
« Reply #12 on: August 24, 2008, 01:37:41 PM »
I carry a extra set of these with me.
Logged
18 grand and 18 miles dont make you a biker
Pages: [1]   Go Up
« previous next »