Author Topic: Cheap coils on ebay  (Read 1834 times)

Offline MarkCR750

  • Professional half wit and member
  • SOHC Master
  • Posts: 1173
    • View Profile
Cheap coils on ebay
« on: May 27, 2014, 04:47:47 PM »
I just bought a pair of these, look ok, I'll report back when fitted.

http://www.ebay.co.uk/itm/200570244121?_trksid=p2055119.m1438.l2649&ssPageName=STRK%3AMEBIDX%3AIT
Suzuki GT250A (Nostalgia)
1977 K7 CR750 (lookalike, what of I’m not sure)
Ducati 900SS (Soul & Speed)
Ducati M900 Monster (Handling & character)
Thruxton 1200 (suits me)
James Captain 197 (pure adrenaline, i.e. no brakes!)
"Eff yir gitten awvestear yir gooin te farst"
Sir J.Stewart.

Offline Green1

  • SOHC Jedi
  • Posts: 2656
    • View Profile
Re: Cheap coils on ebay
« Reply #1 on: May 27, 2014, 08:09:09 PM »
Iv bought quit a few odds and sods from them in the past for various bikes all been good so far.
Fingers crossed.

Mick 
Current bikes
Honda CB750k1 Valley Green Metallic
Honda CB750k1 Candy Gold
Honda CB550k Candy Jade Green
Honda CG125
Aprilia Pegaso 650
Moto guzzi 1200 sport
Kawasaki EX650R (Mine until dave pays for it)
Kawasaki ZXR400 J

Offline MarkCR750

  • Professional half wit and member
  • SOHC Master
  • Posts: 1173
    • View Profile
Re: Cheap coils on ebay
« Reply #2 on: May 27, 2014, 08:14:10 PM »
Yes I had some bearings from them recently, if I remember correctly it was about £3 for the sprocket carrier bearing delivered!, nice bearing, lets hope the coils are as good, they look the part in the photo's.
Suzuki GT250A (Nostalgia)
1977 K7 CR750 (lookalike, what of I’m not sure)
Ducati 900SS (Soul & Speed)
Ducati M900 Monster (Handling & character)
Thruxton 1200 (suits me)
James Captain 197 (pure adrenaline, i.e. no brakes!)
"Eff yir gitten awvestear yir gooin te farst"
Sir J.Stewart.

Offline Green1

  • SOHC Jedi
  • Posts: 2656
    • View Profile
Re: Cheap coils on ebay
« Reply #3 on: May 27, 2014, 08:21:49 PM »
Don't get peeps started on delivery charges you know what there like on this forum. :D

Mick
Current bikes
Honda CB750k1 Valley Green Metallic
Honda CB750k1 Candy Gold
Honda CB550k Candy Jade Green
Honda CG125
Aprilia Pegaso 650
Moto guzzi 1200 sport
Kawasaki EX650R (Mine until dave pays for it)
Kawasaki ZXR400 J

Offline Piki

  • SOHC Expert
  • Posts: 436
    • View Profile
Re: Cheap coils on ebay
« Reply #4 on: May 28, 2014, 11:08:18 AM »
One question, the coils from a 750 Four, Goldwing 1000, etc,etc, are more powerful than the coils of a 400 Four, 500 Four?
If  are more powerful, that is not bad idea, fit one coils from a Goldwing or 750 Four in my 400 Four, and I will get more Spark.....or am I wrong?

Offline Bryanj

  • Grogu
  • *
  • Posts: 10828
    • View Profile
Re: Cheap coils on ebay
« Reply #5 on: May 29, 2014, 09:54:05 AM »
DO NOT use 'Wing as they are ballasted coils

Offline Piki

  • SOHC Expert
  • Posts: 436
    • View Profile
Re: Cheap coils on ebay
« Reply #6 on: May 29, 2014, 10:50:25 AM »
Thank you Bryanj, but I do not know that is "Ballasted coils" 750 four are similar a 400/500/550...

Offline Bryanj

  • Grogu
  • *
  • Posts: 10828
    • View Profile
Re: Cheap coils on ebay
« Reply #7 on: May 30, 2014, 08:55:42 AM »
Physically yes but the resistance varies

Offline Lobo

  • Lobo
  • SOHC Master
  • Posts: 1568
  • Lobo
    • View Profile
    • Lobo
Re: Cheap coils on ebay
« Reply #8 on: May 30, 2014, 09:38:34 AM »
Hi Piki, as I understand it... and not related / specific to Hondas... but 'just generally'....

A ballasted coil typically runs at a lower voltage .... say 6-9 volts, and this is achieved with the use of a resistor by-pass wire. It is all to help starting; ie when the starter motor cranks this resistor is shorted out ... allowing full available battery voltage to the coil (which will now be less than 12v due the starter load), and giving a better spark. Once cranking stops the resistor is put back into the circuit, and the reduced 6-9 volts now feeds the coil. Because the coil is basically designed to run at 6-9 volts the spark is strong / adequate and the engine continues to run just fine.

On your 400F, the coils are un-ballasted, and are designed to run at 12v. During cranking the battery voltage may likely drop to around 10v, and the spark will become weaker. Not ideal, but good enough in this case. Once your stater has ceased cranking the voltage will return to 12v or so and full spark will return.

So, as Bryan says, "the resistance varies", .... and according to starter cranking. Your 400F circuit is not designed for ballasted coils, and by swapping coils between systems you either run the risk of under-voltage / weak spark or running them at over voltage & burning your coil / points out.

I think...!

Hope this helps,
Simon
« Last Edit: May 30, 2014, 09:42:53 AM by Lobo »

Offline Cabilao

  • Diving,Driving,Dining,what else???
  • Newbie
  • Posts: 21
  • Life is a Bitch.....sometimes!!!!
    • View Profile
    • Sea-Explorers
Re: Cheap coils on ebay
« Reply #9 on: May 30, 2014, 10:54:36 AM »
Thanks Lobo,good explanation,i also had no clue about ballasted coils. You never stop learning ;)
before:
Kreidler RMC(50cc)
CB400N(first bike)
RD350LC(more than one)
XS850(great bike)
CB900F(wish i still have it)
FZR1000(too fast)
Rickman CR900(sold for a good price)
now:
TMX 155(just for fun)
CB750P7 (current Project)

Offline Piki

  • SOHC Expert
  • Posts: 436
    • View Profile
Re: Cheap coils on ebay
« Reply #10 on: May 30, 2014, 12:20:53 PM »
Great Lobo, you are great!!! I remember that some member from the USA website made this upgrade in his 400/500 fours: good originals points, and change the coils for coils of Goldwing 1000,but perhaps I am wrong.......

But if the coils of 750 Four and Goldwing are different that coils from 400/500/550, why DSS sell the aftermarket coils with  the same Part Number!!!!  :o :o ;) ;)

Offline Lobo

  • Lobo
  • SOHC Master
  • Posts: 1568
  • Lobo
    • View Profile
    • Lobo
Re: Cheap coils on ebay
« Reply #11 on: May 30, 2014, 03:17:30 PM »
Hi Piki,

Just to say again... my post was 'general' and not specific to Honda motorcycles.  I've no idea etc of DSS part numbers, or whether Gold Wing coils are different to 400F coils. Forgive me...
(but if the part #s are the same...well surely it'd be fine) Bryan... thoughts / comments?

If however, you substitute a ballasted coil (designed to run @ 9v) into an unballasted circuit ... it may well mean you're running the coil at 12v continuously  ... versus its 9v design... meaning something (ie the points / coil) will fail earlier than their intended life. I accept though, in the short term, it may appear better than spec, & just fine.

As a general rule... and I am no engineer / specialist ... I'd suggest, whether it be tyre dimensions, oil, petrol... whatever.. you should stick to what the manufactures intended versus thinking you (we) can do better!

Cheers,
Simon
« Last Edit: May 30, 2014, 03:59:11 PM by Lobo »

 

SimplePortal 2.3.5 © 2008-2012, SimplePortal