Author Topic: Starter Relay Fuses Question  (Read 1711 times)

Offline Piranha Brother 2

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Re: Starter Relay Fuses Question
« Reply #15 on: November 09, 2019, 06:07 »
If it's the same as the one I used on my RGA about 15 years ago, the fuse is nothing to do with the starter, it is a main fuse for the rest of the bike.  The two separate pins you observe do indeed operate the relay coil in the normal manner with a +12 and GND, one of which is switched via the start button.
The fuse is internally powered from the battery +ve lead, and the output of it powers up the ignition switch, so it performs the same function as the 25A fuse in a BTZ180 or RGS or the 30A fuse in a Mk1 180.
It's nice since it allows you to just have one large lead on the +-ve battery terminal.  I power the bike from that 30A fuse and terminate my regulator charge wire at the start relay post and therefore only have one large lead on battery +ve (as per a modern bike).  The two conjoined output pins allow you to power both switched and unswitched smaller fuses.  On my bike I power three fuses via the ignition switch and one fuse for 'always on' ECU standby power.

That's great info, Steve. Makes a lot more sense now - I checked and one of the fuses is just a spare. So IIUC I can run the 12+ from the starter button to either of the copper individ pins and the other copper pin to ground? That's my starter relay circuit taken care of.

Then I can use the 'conjoined' pin as a takeoff to either the main switched 12+ power to the bike's fuses or to an unswitched fused item (if I had one, eg a battery charge input?) - or both. What sort of female connector plugs onto that conjoined blade? It's a main power feed rated to 30A, yes? I agree it's a good sys as I hate having loads of eye terminals bolted to my battery +

Is yours exactly the same as the on pin my pic and if so where I can I source the block connector that goes into it? Or if you know what bike it comes off I could go back to Vic Wreckers and see if I can get one. It looks as if it'll be specific to that block connector.

Next I have to fit all the ancillaries where they'll be going and start cutting wire and adding connectors! ... and make a pair of sidecovers ... and and and ...     :'(
What ... leave it standard??!!

Offline Laverda SF

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Re: Starter Relay Fuses Question
« Reply #16 on: November 09, 2019, 06:34 »
So you guys are bragging you got Transistors, Mosfets and ECM's regarding improving the running circuit for a SF - Suppose your using LEDs rather then 1157 Bulbs - That's not original  - Go for it - Trust you will beat the original .

There's a lot of SF's left out there to be defamed. Yes she's a very FAST antique 750 by reputation even by to days standard - Do her Justice.

As if a Breganzie 750 SF can't do a wheelie in 2nd - Apparently, she wasn't tuned ;o)
« Last Edit: November 09, 2019, 07:25 by Laverda SF »

Offline CLEMTOG

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Re: Starter Relay Fuses Question
« Reply #17 on: November 09, 2019, 15:18 »
down hill in the wet, or over a hump backed bridge?
CLEM

Offline breganzane

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Re: Starter Relay Fuses Question
« Reply #18 on: November 09, 2019, 21:42 »
...........
What sort of female connector plugs onto that conjoined blade? It's a main power feed rated to 30A, yes? I agree it's a good sys as I hate having loads of eye terminals bolted to my battery +
Is yours exactly the same as the on pin my pic and if so where I can I source the block connector that goes into it? Or if you know what bike it comes off I could go back to Vic Wreckers and see if I can get one. It looks as if it'll be specific to that block connector.

I don't recognise the connector on the type you have there which seems to be a more modern relay than I used.  You find there are only a few variants of these start relays used on all bikes across the ages, I don't know what the one i used came off but it is very common from the 90's and looks like this:

That one used normal 1/4" spade terminals, I think I might have used a connector housing commonly available locally but not exactly correct and modified it to suit (cut two small grooves).  These days you can get all the funny plugs quite easily from easternbeaver or cycle terminal.

Going back to Vicwreckers and seeing if they'll provide a pigtail to suit will help somewhat but I always prefer to properly terminate fresh terminals rather than splicing in a pigtail, particularly when it's the main feed for the bike.  Solder joints are prone to failure through vibration, and ... well... err.... Laverdas do occasionally vibrate a little. :D  Perhaps you can swap yours for one like the above including the mating connector and then re-terminate the plug with new 1/4" terminals which are easily sourced locally.
Various 120, 180 and 360 Laverdas - and a single.

Offline Piranha Brother 2

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Re: Starter Relay Fuses Question
« Reply #19 on: November 09, 2019, 21:53 »
Good info once again - thanks Steve. I would never splice and solder - if I can get the male block I'll crimp up new terminals. Might take your advice and go back to VR and see if I can get either the block or an alternative relay.The copper pins on mine are never going to survive unless they're held in place by the plastic block!!  And what are you saying ... Laverdas do vibrate no and then??!!  :laugh: :laugh: :laugh:
What ... leave it standard??!!

Offline Dellortoman

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Re: Starter Relay Fuses Question
« Reply #20 on: November 09, 2019, 23:49 »
Solder joints are prone to failure through vibration ...

I'm a fan of soldered joints. In the 50+ years I've been messing about with bikes, I've never had a soldered splice fail. I also solder terminals after crimping because I've had too many crimped joints fail.

Location: Tasmania, Approx 42į53íS 147į23íE

Offline motoddrob

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Re: Starter Relay Fuses Question
« Reply #21 on: November 10, 2019, 02:16 »
The pic of Steve's relay is the same as the one I brought for the Motodd. So far so good. Think I got it off fleabay.
Motodd 1200, SFC750

Offline Legs

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Re: Starter Relay Fuses Question
« Reply #22 on: November 10, 2019, 06:18 »
You looken at me?

Offline Andy

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Re: Starter Relay Fuses Question
« Reply #23 on: November 10, 2019, 23:36 »
I think itís been said but worth repeating: donít use a second hand socket from the wreckers!
If you canít find a new socket then use single connectors.
Like Cam, Iím a fan of soldering over crimped connectors where possible, although this isnít universally popular...(I think for reasons of corrosion and vibration?)
'84 RGS and loving it
(might have to sell the old honda...)

Offline Piranha Brother 2

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Re: Starter Relay Fuses Question
« Reply #24 on: November 11, 2019, 00:09 »
I only want the plastic housing so I can fit new terminals. I have a fancy pair of crimpers that do a pro job. Would never just connect old wires unless they were long enough to reach the appliance Iím connecting to.
What ... leave it standard??!!

Offline Piranha Brother 2

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Re: Starter Relay Fuses Question
« Reply #25 on: November 12, 2019, 10:10 »
Very helpful guy at Vic wreckers found me a connector with a decent length of wire attached, so I can add terminals to the other end. All good! Now back to making my sidecovers plug!!
What ... leave it standard??!!