Fitting Dyna Coils to 81 MHR.. Ballast Resistor Needed?

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Misterb
Cucciolo - the Lil Pup
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Fitting Dyna Coils to 81 MHR.. Ballast Resistor Needed?

Post by Misterb »

One of the coils on my 81 MHR has a problem.. the low tension wire has broken right where it enters the coil. So I've decided to replace them both with new 5 ohm Dyna coils.. DC-10-1. The question is do I still need to keep the ballast resistors when using these new coils. I have read a few old threads on here on the subject, but haven't seen a clear answer.

Thanks.
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BevHevSteve
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Re: Fitting Dyna Coils to 81 MHR.. Ballast Resistor Needed?

Post by BevHevSteve »

Image
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Misterb
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Re: Fitting Dyna Coils to 81 MHR.. Ballast Resistor Needed?

Post by Misterb »

Thanks, will do.
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81mhr900ss
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Re: Fitting Dyna Coils to 81 MHR.. Ballast Resistor Needed?

Post by 81mhr900ss »

Steve: do you have a picture of your bracket kit on a bike that you can share?
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BevHevSteve
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Re: Fitting Dyna Coils to 81 MHR.. Ballast Resistor Needed?

Post by BevHevSteve »

Pretty sure there is a photo showing installed on the bracket kit product page...
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BevHevSteve
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Re: Fitting Dyna Coils to 81 MHR.. Ballast Resistor Needed?

Post by BevHevSteve »

Image
Image
Steve Allen (925)798-BEVL[2385] Ride'm, Don't Hide'm
Ducati/Euro Spares -> https://Store.BevelHeaven.com
Misterb
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Re: Fitting Dyna Coils to 81 MHR.. Ballast Resistor Needed?

Post by Misterb »

The Dyna coils are a little fatter than the NP originals, and so wont fit in the OE position … in the triangle made by the two down tubes and the cross brace under the headstock. In the pic above the coils are mounted on the brackets used to mount the ignitor boxes on my 81 MHR. Did the bike pictured not use these ignitor boxes anymore, or where they in turn moved elsewhere?
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BevHevSteve
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Re: Fitting Dyna Coils to 81 MHR.. Ballast Resistor Needed?

Post by BevHevSteve »

The photo doesn't show an MHR.... its a Sport or a GT, can't remember exactly.

The brackets don't fit anything exactly except the coils. The point of using them is that they are a huge time saver and can easily be modified to fit most of our bikes.
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Steve Allen (925)798-BEVL[2385] Ride'm, Don't Hide'm
Ducati/Euro Spares -> https://Store.BevelHeaven.com
Misterb
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Re: Fitting Dyna Coils to 81 MHR.. Ballast Resistor Needed?

Post by Misterb »

Ok, thanks again.
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geodoc
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Re: Fitting Dyna Coils to 81 MHR.. Ballast Resistor Needed?

Post by geodoc »

Worked well fitting on my GT:

Image






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81mhr900ss
750 GT
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Re: Fitting Dyna Coils to 81 MHR.. Ballast Resistor Needed?

Post by 81mhr900ss »

misterb: any pics of your installation? I'm considering the same.
Misterb
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Re: Fitting Dyna Coils to 81 MHR.. Ballast Resistor Needed?

Post by Misterb »

The Dyna coils have to sit a little forward of their original position as they are too fat to fit between the frame down tubes.. I made the low tension wires over length as it made wiring everything up easier. Probably made them too long, and may shorten them, depends if they are still visible with the tank in place..
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NorleyStart4andMHRFInalCoils 004.JPG
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81mhr900ss
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Re: Fitting Dyna Coils to 81 MHR.. Ballast Resistor Needed?

Post by 81mhr900ss »

Initially, reused the old Ducati frame and planned to hang the coil block from the old Bosch frame plates but changed my mind and made a hybrid bracket; still uses the cradles from the old Ducati coil frame but mounts roughly in the middle under the tank with one coil feeding forward and the other backward:
Image
Image
Image
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geodoc
750 GT
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Re: Fitting Dyna Coils to 81 MHR.. Ballast Resistor Needed?

Post by geodoc »

Very tidy. Nice touch with the red ty-wraps.

Use these guys?

http://www.cycleterminal.com/

Or these ones?

http://www.vintageconnections.com/




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