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Best possible relay for coil relay mod?

GabrielGoes

Forum Mentor
What is the best? Are there any made in Japan relays? The coil relay mod is a Great mod love it but don't love having a poorly made crap chinese relay running my motorcycle. I know I can carry a bag full of them but who in the world would want that.
 
Have to say that the relay "mod" isn't really a mod but a bit of a bodge to disguise poor connections elsewhere in the ignition wiring and kill switch.
You'll be better off ensuring that all connections of the original wiring are functioning as they should which will make fitting a relay a waste of time , money and would avoid adding an additional potential source of failure.
 
you can just use a 4 pin horn relay from oriellys, ive had mine never fail and its been on there for atleast 6 months now,
 
Have to say that the relay "mod" isn't really a mod but a bit of a bodge to disguise poor connections elsewhere in the ignition wiring and kill switch.
You'll be better off ensuring that all connections of the original wiring are functioning as they should which will make fitting a relay a waste of time , money and would avoid adding an additional potential source of failure.

Straight facts sir. But refreshing all the grounds and switch and connectors still won't resolve this a lot of times but instead the interior oxidation and deterioration of the wires themselves are definitely what drop the volts over the distances id say, and the relay to get 12v fed from the battery is just an easier route and a new harness isn't always necessary.
 
I use Bosch relays when available.
Which reminds me - I used a few cheapo ones that need to be replaced for peace of mind.
 
Have to say that the relay "mod" isn't really a mod but a bit of a bodge to disguise poor connections elsewhere in the ignition wiring and kill switch.
You'll be better off ensuring that all connections of the original wiring are functioning as they should which will make fitting a relay a waste of time , money and would avoid adding an additional potential source of failure.

My thoughts exactly. I put the mod on one of my bikes early in my GS career but just hated all the needless wires. Took it off and cleaned the terminals instead.
 
My thoughts exactly. I put the mod on one of my bikes early in my GS career but just hated all the needless wires. Took it off and cleaned the terminals instead.

Bingo............
 
Have to say that the relay "mod" isn't really a mod but a bit of a bodge to disguise poor connections elsewhere in the ignition wiring and kill switch.
You'll be better off ensuring that all connections of the original wiring are functioning as they should which will make fitting a relay a waste of time , money and would avoid adding an additional potential source of failure.

+1
The relay is sweeping things under the carpet. Sooner or later all the connections will have to be dealt with.
 
Even with everything perfect, you still get some voltage drop, and some folks install a relay anyway. There are a lot of connections along the way.

But yes, you should definitely clean, test, and replace until you have minimal voltage drop, and the bike starts and runs perfectly without a relay. And if you do install a relay, make sure you leave yourself an easy path back to stock if the relay ever fails. Maybe zip-tie a jumper or spare relay somewhere close, or have a plan for which terminals to plug together.

Anyway, to answer the question... these are the finest relays on the planet, Matsu s h i t a/Panasonic:
https://www.easternbeaver.com/Main/Elec__Products/Relays/relays.html

Eastern Beaver is a guy from the US living in Japan who sources Japanese electrical goodies and ships worldwide.


All the above said, relays are a very mature technology, and so any decent brand like Bosch or Tyco will be fine. Avoid anything with no name or a name you haven't heard of. You definitely want a sealed relay, and pay attention to how its mounted to ensure it's not exposed to a lot of vibration. You also want to make sure you get the wiring 100% correct to ensure you're not trying to trigger the relay with AC or something weird like that (yes, I've actually seen this. The poor relay buzzed fiercely for a while but didn't last long...).

I generally install an accessory relay circuit to power heated grips, phone charger, etc. and for high-amperage draw horns. But it really is best to get the wiring in good shape so you don't need a relay for the bike to run. And some folks, even on modern bikes, install a relay circuit (Eastern Beaver sells kits) for the headlights to get that last .2 volt and make the headlight just a tiny bit brighter, or to work around undersized stock headlight wiring (for example, on the V-Strom, Suzuki grounds both headlights through the same teensy-weensy wire with a teensy-weensy failure-prone connector, and it's a common problem.)
 
Even with everything perfect, you still get some voltage drop, and some folks install a relay anyway. There are a lot of connections along the way.

But yes, you should definitely clean, test, and replace until you have minimal voltage drop, and the bike starts and runs perfectly without a relay. And if you do install a relay, make sure you leave yourself an easy path back to stock if the relay ever fails. Maybe zip-tie a jumper or spare relay somewhere close, or have a plan for which terminals to plug together.

Anyway, to answer the question... these are the finest relays on the planet, Matsu s h i t a/Panasonic:
https://www.easternbeaver.com/Main/Elec__Products/Relays/relays.html

Eastern Beaver is a guy from the US living in Japan who sources Japanese electrical goodies and ships worldwide.


All the above said, relays are a very mature technology, and so any decent brand like Bosch or Tyco will be fine. Avoid anything with no name or a name you haven't heard of. You definitely want a sealed relay, and pay attention to how its mounted to ensure it's not exposed to a lot of vibration. You also want to make sure you get the wiring 100% correct to ensure you're not trying to trigger the relay with AC or something weird like that (yes, I've actually seen this. The poor relay buzzed fiercely for a while but didn't last long...).

I generally install an accessory relay circuit to power heated grips, phone charger, etc. and for high-amperage draw horns. But it really is best to get the wiring in good shape so you don't need a relay for the bike to run. And some folks, even on modern bikes, install a relay circuit (Eastern Beaver sells kits) for the headlights to get that last .2 volt and make the headlight just a tiny bit brighter, or to work around undersized stock headlight wiring (for example, on the V-Strom, Suzuki grounds both headlights through the same teensy-weensy wire with a teensy-weensy failure-prone connector, and it's a common problem.)

Thanks for the link to that relay, Brian.

I know there are pros and cons to this mod. After 5k miles I haven't regretted doing it. I do carry a spare relay just in case though. The spare is secured under the side cover near the fuse block.

Here are the lousy stock connectors to the coils. This was contributing to the loos of voltage, but not the only culprit.





(I hate seeing the blue goop I used to seal the new spark plug wires, but it serves it's purpose)
 
Even with everything perfect, you still get some voltage drop, and some folks install a relay anyway. There are a lot of connections along the way.

But yes, you should definitely clean, test, and replace until you have minimal voltage drop, and the bike starts and runs perfectly without a relay. And if you do install a relay, make sure you leave yourself an easy path back to stock if the relay ever fails. Maybe zip-tie a jumper or spare relay somewhere close, or have a plan for which terminals to plug together.

Anyway, to answer the question... these are the finest relays on the planet, Matsu s h i t a/Panasonic:
https://www.easternbeaver.com/Main/Elec__Products/Relays/relays.html

Eastern Beaver is a guy from the US living in Japan who sources Japanese electrical goodies and ships worldwide.


All the above said, relays are a very mature technology, and so any decent brand like Bosch or Tyco will be fine. Avoid anything with no name or a name you haven't heard of. You definitely want a sealed relay, and pay attention to how its mounted to ensure it's not exposed to a lot of vibration. You also want to make sure you get the wiring 100% correct to ensure you're not trying to trigger the relay with AC or something weird like that (yes, I've actually seen this. The poor relay buzzed fiercely for a while but didn't last long...).

I generally install an accessory relay circuit to power heated grips, phone charger, etc. and for high-amperage draw horns. But it really is best to get the wiring in good shape so you don't need a relay for the bike to run. And some folks, even on modern bikes, install a relay circuit (Eastern Beaver sells kits) for the headlights to get that last .2 volt and make the headlight just a tiny bit brighter, or to work around undersized stock headlight wiring (for example, on the V-Strom, Suzuki grounds both headlights through the same teensy-weensy wire with a teensy-weensy failure-prone connector, and it's a common problem.)

agreed- exactly my point, even without corrosion the loss through the distance and resistance will definitely net a significant loss from the original power source.

I also don't like "modifying things" so I get where the other guys are coming from.

Thank you so much for posting that link with the Japanese relay's - its beyond wonderful
 
Have to say that the relay "mod" isn't really a mod but a bit of a bodge to disguise poor connections elsewhere in the ignition wiring and kill switch.
You'll be better off ensuring that all connections of the original wiring are functioning as they should which will make fitting a relay a waste of time , money and would avoid adding an additional potential source of failure.


i agree, but at the same time cleaning everything doesnt always get you the 12volts the ignition needs unfortunately, i was only able to get up to 10.5v and that is deep cleaning all the connections and replacing any noticeably corroded wires. at first i just wanted to keep it all original because it does just what you say, it just covers up the real problem but i also am glad i did mine just because ive had no issues with a weak voltage since installation.

you can always clean all you can and see if you're able to gain back to the appropriate voltage, i actually had fun seeing voltage getting gained back after doing some good cleanings, but i just was never able to get the full 12 volts i needed.
 
Just zip tie or tape a spare relay somewhere close by. I've never had one quit despite running one for many thousands of miles on 3 different GS's..... I modified the Skunk recently with a PC-8 fuse box & used a relay to run all the switched circuits. Worked fine.

Eastern Beaver does some very high quality relays but for me I wanted a "bosch" standard format as you can pick those up cheaply in basically any auto store in the world.....

You can also get a 3" length of 14ga wire & put a male spade connector on each end. In a pinch you "hot wire" 30 - 87. Just remember to remove it again right away each time you stop. You basically become a "manual" relay that way... (you do the job the relay does with the jumper wire).
 
Just zip tie or tape a spare relay somewhere close by. I've never had one quit despite running one for many thousands of miles on 3 different GS's..... I modified the Skunk recently with a PC-8 fuse box & used a relay to run all the switched circuits. Worked fine.

Eastern Beaver does some very high quality relays but for me I wanted a "bosch" standard format as you can pick those up cheaply in basically any auto store in the world.....

You can also get a 3" length of 14ga wire & put a male spade connector on each end. In a pinch you "hot wire" 30 - 87. Just remember to remove it again right away each time you stop. You basically become a "manual" relay that way... (you do the job the relay does with the jumper wire).

Excellent ideas an points mate
 
There is another issue with the coil relay mod that needs to be pointed out. Yes, giving the coils full voltage will, indeed, make the bike run better. Now that it's running better, you might enjoy riding it more, you might even stay out after dark. Then you will realize that your LIGHTS are not getting full voltage, either. Why not install the headlight relay mod, too? Oh, yeah, there is a third fuse in the panel, might as well install another relay for that one, too.

Or, ... you can install a single relay that will be triggered by the ignition key that will provide full power to the ENTIRE bike. The ignition switch is often the major culprit regarding voltage loss, so if you bypass IT, you won't need relays for all the individual stuff. Unless you add things like grip heaters, outlets for heated clothing, microwave ovens, etc.
 
There is another issue with the coil relay mod that needs to be pointed out. Yes, giving the coils full voltage will, indeed, make the bike run better. Now that it's running better, you might enjoy riding it more, you might even stay out after dark. Then you will realize that your LIGHTS are not getting full voltage, either. Why not install the headlight relay mod, too? Oh, yeah, there is a third fuse in the panel, might as well install another relay for that one, too.

Or, ... you can install a single relay that will be triggered by the ignition key that will provide full power to the ENTIRE bike. The ignition switch is often the major culprit regarding voltage loss, so if you bypass IT, you won't need relays for all the individual stuff. Unless you add things like grip heaters, outlets for heated clothing, microwave ovens, etc.

Interesting, we'll form a relay christmas tree under and around the tank!!
 
wait am i really losing voltage to my headlight from having a coil relay mod? if so howmuch is it usually? i can see at night pretty well but i always wished it was a bit brighter.
 
I did the coil relay mod to my GS750 when I first got it in 2016 with a generic four pin relay from advanced auto or something similar. Five years and 25,000 miles later, it failed this summer, which took about a minute to diagnose when I didn't hear the relay clicking when toggling the kill switch. Took another 5 minutes to splice a couple of wires together to get home (I know this is potentially dangerous). I bought another two-pack of relays, swapped it out and now just keep the extra on the bike for when it fails in another ~2-?? years.

Funnily enough, I had a couple of those eastern beaver relays I had bought a couple of years ago since and couldn't find it in the shed when this all happened!
 
I did the coil relay mod to my GS750 when I first got it in 2016 with a generic four pin relay from advanced auto or something similar. Five years and 25,000 miles later, it failed this summer, which took about a minute to diagnose when I didn't hear the relay clicking when toggling the kill switch. Took another 5 minutes to splice a couple of wires together to get home (I know this is potentially dangerous). I bought another two-pack of relays, swapped it out and now just keep the extra on the bike for when it fails in another ~2-?? years.

Funnily enough, I had a couple of those eastern beaver relays I had bought a couple of years ago since and couldn't find it in the shed when this all happened!

Wow good data! So i am assuming it was a no name Chinese brand relay that failed?
 
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