Fitting a relay to ignition coil feed

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barney01
Posts: 3118
Joined: Wed Sep 26, 2012 7:33 pm
Location: Prestatyn.Wales

Fitting a relay to ignition coil feed

Post by barney01 »

Just in the process of fitting a relay into ignition coil feed to my GT550. I'm not a sparky, it's all double dutch to me, what is the amps drawn by the coil feed wire? I have some 5 amp cable is that big enough? I'm also fitting an in line fuse, what size fuse should I fit?
All offers of advice would be appreciated.
NO SMOKE .......NO POKE
teazer
Posts: 1035
Joined: Mon Mar 07, 2011 8:10 pm
Location: Chicago

Re: Fitting a relay to ignition coil feed

Post by teazer »

This is easy but don't rush it. There are two ways to do this. One is to leave the stock 6 connector socket in the old harness and wire in a new connector. The other is to open up the harness and remove the power feeds (orange) to the coils.

If you choose door number one, you still have to connect the new coli to points leas to the old ones, so it's not really an advantage.

When you open up the harness, you are looking for the orange leads to the coils. Follow them back from the connector and then snip that. Those three leads will now need to be connected to the relay Power Out (usually Terminal 87). Connect a new lead to the orange in the harness and connect it to terminal 86. Terminal 87 goes to ground at any convenient location. Then connect the fused power line from the battery to Terminal 30.

When power is ON at the switches, the connection between 86 and 85 closes the contacts and allows power to flow through 30 to 87 to run the coils. A 10 amp fuse should be more than enough, and I tend to go up a size on the power (30) lead and ground lead(85) just to be sure there's no voltage drop.
barney01
Posts: 3118
Joined: Wed Sep 26, 2012 7:33 pm
Location: Prestatyn.Wales

Re: Fitting a relay to ignition coil feed

Post by barney01 »

Thanks, so 5amp cable no good then. I have Newtronic fitted so already have cut into loom so no problem there. Will go for cable in excess of 10amp
NO SMOKE .......NO POKE
barney01
Posts: 3118
Joined: Wed Sep 26, 2012 7:33 pm
Location: Prestatyn.Wales

Re: Fitting a relay to ignition coil feed

Post by barney01 »

So did the work today. I have the original loom and I measured power to the coils ignition on only 10.8v. Bike was running fine though.
Fitted 30amp four pin relay from Halfords.
10amp fuse in a waterproof holder
17amp cable for power supply AND earth
Measured again power at coils 12.2v.
Bike started first kick from cold, it normally takes a couple of kicks.
Seems to run smoother in low revs,
I'm happy! :D
NO SMOKE .......NO POKE
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