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General Category => General Discussion => Topic started by: Breva-Al on August 31, 2017, 01:39:37 PM

Title: Breva 750 / BAE 850 Coil resistance.
Post by: Breva-Al on August 31, 2017, 01:39:37 PM
Hi
I am new on here, so please be gentle
I hope some one can help. I am trying to find out the primary and secondary resistance of Magneti Marelli BAE 850 AK coil as fitted to a Breva 750 along with many other Guzzis from the 90s and 00s
I have searched the site and can find references to testing the coils but not the values.

Cheers
Al
Title: Re: Breva 750 / BAE 850 Coil resistance.
Post by: Kiwi_Roy on August 31, 2017, 04:28:54 PM
I don't know the answer but compare the readings left and right, should be identical.

If you measure from plug cap to chassis it will measure the cap, lead & coil in one go, I suspect it would be about 8k judging from other models I have tried. For sure it should be the same.
Title: Re: Breva 750 / BAE 850 Coil resistance.
Post by: Breva-Al on September 01, 2017, 02:31:18 AM
Thanks Kiwi_Roy,
I had considered that approach and will most likely take it.
I have trawled the internet and have found very little information on this particular coil and what information there is is conflicting. the primary is quoted as being .6 - .7 ohm on one site and 2.2  ohms on another. same issue with secondary with ranges from 3200  ohms to over double that.
I was just hoping someone had the spec for this coil.
I have asked Magneti Marelli but have not received a response yet.

Thanks for your advice

Al
Title: Re: Breva 750 / BAE 850 Coil resistance.
Post by: Kiwi_Roy on September 01, 2017, 09:14:44 PM
If you had one bad coil that would be unusual but two bad at the same time would be next to impossible.

I used to like working on stereos because you always had one good channel to compare against.

Good Luck
Title: Re: Breva 750 / BAE 850 Coil resistance.
Post by: Breva-Al on September 03, 2017, 05:16:45 AM
Thanks Kiwi_Roy,
The problem was a loose HT lead connection to one of the coils, only held on by the rubber boot.
Made up a new set of HT leads with new plug caps just to be on the safe side.
For information
Primary - measured between the + and - terminals =  .5 ohms
Secondaries - measured between the + terminal and the HT socket = 3250 ohms

Al