3c starter relay

And the risk of the contacts welding themselves together increases exponentially.
Cue smouldering insulation, smoke and possible flame.
I've lived through that nightmare and never want to, again.
Get a new modern Start relay/Solenoid.
Avoid the plastic-cased Bosch ones like the plague.
 
Best using a diamond file for contacts as emery cloth or sand paper leaves minute particles on the contact area, this will make these surfaces fail quicker due to the impurities. Don't go mad though, once the toughened surface is gone the exponential deterioration will occur.
 
Just to twist the plot in another direction...

I had the original relay jam on my 3C on the return trip from Breganze 1983. Disconnected the battery in a hurry, dismantled the relay by the roadside near Passo Pasubio, ie, in the middle of BFN, got it working and it's been on the bike since then! I did clean it up properly upon my arrival home but haven't touched it since, I see no need to replace it. It is in fact one of the last remaining original bits (next to the ignition switch and most parts of the frame) left on the bike, all of which still perform faultlessly. ;)

Imho, the relays fail through excessive current drain, mostly caused by dodgy starter motors. Once I caught on to this issue, I've not suffered any sort of starting problems.

piet
 
Yesterday I installed the starter relay from Hitachi that was recommended here.

54106546171_89fda7f76d_z.jpg


The initial bracket I did for the new relays (thanks Jürgen!) had to be modified to move the relay back by another 35mm to situate it better in the room between battery and air box. Yet for this I’ll come up with a more elegant (and lighter) solution though ...
 
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I have now owned TOG (1200TS) for 44 years, the starter relay failed at about 5 years, and even then the cost of the 80amp Bosch relay was off the clock, so I fitted a used SOLENOID (not a relay) from a Land Rover, this was very successfull, so I bought a new one and quickly chopped it over, I fitted it under the batterry tray. The advantages are that
a) it is very cheap, currently less than £15
b) there is a "full volts" tag when the starter is cranking, which gives battery voltage up stream of the coil voltage droppers (stock BTZ system).
c) has a tag for ignition off and live,
d) has a tag for ignition on and live.
e) its a solenoid not a relay, some have a manual button for the high amp side.

c and d very usefull for accessory socket and satnav etc.
I had to fit a replacement about 15 years ago.

for supplies .........eBay item number:324222261980
CLEM
 
Difference between a solenoid and a relay? My info from professor Google says:
The difference between a relay and a solenoid is that the latter is used to evoke action and not transfer current. A solenoid has two wires: power and ground. It is an electromagnet (as in the pull-in part of a relay), but it usually connects to a mechanical device such as a rod or lever.
The one in the picture looks like a good strong starter relay (cannot see the back side of it), my experience with starter solenoids was that they fire up the electro magnet to operate the shaft that engages a pinion gear to the flywheel ring gear as well as closing the contacts to run the starter motor.
 
eBay item number:324222261980 brings this up, for me, Quentin.
Maybe searching by title might work?

View attachment 93318
Still no joy, but I found them for sale in Oz anyway - more expensive but cheaper shipping. Not that I need one - the one I use from a big Jap twin seems fine. Has a fused direct feed wire as well (maybe to power coils?). and what looks like a spare fuse.
 
I have now owned TOG (1200TS) for 44 years, the starter relay failed at about 5 years, and even then the cost of the 80amp Bosch relay was off the clock, so I fitted a used SOLENOID (not a relay) from a Land Rover, this was very successfull, so I bought a new one and quickly chopped it over, I fitted it under the batterry tray. The advantages are that
a) it is very cheap, currently less than £15
b) there is a "full volts" tag when the starter is cranking, which gives battery voltage up stream of the coil voltage droppers (stock BTZ system).
c) has a tag for ignition off and live,
d) has a tag for ignition on and live.
e) its a solenoid not a relay, some have a manual button for the high amp side.

c and d very usefull for accessory socket and satnav etc.
I had to fit a replacement about 15 years ago.

for supplies .........eBay item number:324222261980
CLEM
What you've got there Clem is a starter relay, not a solenoid (I agree with Tippie's distinction).

I was having trouble wrapping my head around what all the tags (spade terminals) were that you listed. Also, how can a starter relay know if the ignition is on or off unless it had a separate signal wire telling it the state of the ignition switch? So I found this picture online somewhere.

land rover starter relay.JPG


a) it is very cheap, currently less than £15 Yep, certainly is good value
b) there is a "full volts" tag when the starter is cranking ... Yep, the terminal labelled Coil W/Y. Common in most car starter relays to bypass the coil ballast resistors while cranking.
c) has a tag for ignition off and live,
d) has a tag for ignition on and live.
Cant see either c) or d) ?
e) its a solenoid not a relay. No, it's a relay. There's no solenoid action to engage the starter pinion in this device. That must happen at the starter motor.

What it does have is a couple of positive spade terminals, one 4mm and one 6.3mm (labelled Brown in the photo) that are fed directly from the heavy battery cable (so they're un-fused). Could be handy for something you want to be always energised.

"Start W/R" on the left is the incoming start signal from the starter button.
 
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disagree a bit you lot, the solenoid pictured is slightly different to the ones that I have, the LT tags, but nothing else, the connection between the heavy cables is made by an electromagnet moving a copper bar between the two nuted terminals, the starter (on Land Rovers etc) then spins and a centrifugal drive gear moves to engage the flywheel, much the same on the early (read most) Laverda, even though there is a sprag clutch, later bikes do not have the centrifugal moved gear on the starter (so what)

What you are getting confused with is later starter motors frpom Generic cars, which have the solenoid bolted to the case of the motor and directly engage the drive gear, this type is called "pre- engaged" because the solenoid moves the gear via a lever and the teeth of that engage the fllywheel a fraction of a second before the contacts make.

there is a big cylindrical bulge on the unit pictured (not visible) that is thecoil for the moving core of that copper strap. It can probablty take 400 amps. I still say its a solenoid, no pathetic little contacts at all.

are you going to force me to open up an old one, then get my grandaughter (7) to photograph it and post here? because I cant do that for some reason where I have achieved it in the past.
CLEM
 
According to Wikipedia, a solenoid is an electro magnet that converts electrical into mechanical energy. In our case, a fixed magnetic core is used to mechanically close contacts to supply current to the starter motor. Auto starters with piggy-back solenoids use the movement of a loose core to close the electrical contacts AND to throw out the drive sprocket to engage the flywheel. So, basically, any relay relying on electro magnetic forces contains/is a solenoid. The size of the contacts lastly dictate how much current can be relayed.

A Laverda starter in good nick will rarely draw much more than 40-50 amps if the engine starts immediately (which they do if everything is in order). Dirty, clagged up starters on worn and tired (or hi-comp with tame cams) engines that refuse to start quickly can draw over 200 amps, this quickly destroys any relay with a lower rating. Fitting a heavy duty relay to get an engine to start reliably may just disguise other issues.

If anybody is interested, the big, bulky but bulletproof Bosch relays as used on the early twins is still in production and in use across a large part of the VW/Audi/Porsche model range, especially in premium models with monster engines and terrabyte-sized computers on board. It is used as a "master" relay to power up the entire vehicle and can be found for very small money on eBay. A new genuine item in factory packaging, especially Porsche or Audi, is probably a trillion times more expensive... search for Phaeton, A8, Cheyenne, etc. In comparison, the main relay in my MX5, which in many regards has been far more reliable than any premium VAG product ever could be, is smaller than a matchbox. :rolleyes: Technical overkill, then and now.

Personally, I'm quite content to continue using the small, rectangular Bosch 70A relay, with either metal or plastic case, the internals are the same.

piet
 
.... its the opening ( of the relay contacts, Note* ) of a high draw starter motor current that reduces the contacts integrity, not so much the actual locked armature or run current. Being DC current, once the contacts start to open, under load, its like a lift MMA weld process. Not so very different for your points ( Kettering ) and the use of a snubber ( Capacitor/Resistor network or better ). The snubber for a motor control contact would be unwieldy on a motor cycle as such.

Confirm Piets observations, starter motor ( Bosch SJCE ) cold crank inrush current at some 100-200Adc ( starter motor condition dependent ), compressing motor cranking at around 60-80amps, give or take.

Note *, solenoid is a plunger style mechanical to electrical transfer device, ( Bendix when used on gear/electrical contact ), relay tends to be a rocking armature configuration, in simplified analogy.
HTH j.
 
Note *, solenoid is a plunger style mechanical to electrical transfer device, ( Bendix when used on gear/electrical contact ), relay tends to be a rocking armature configuration, in simplified analogy.
HTH j.
So in effect a solenoid is NOT a relay ... semantically speaking ...? :cool:
 
For the simple life Quentin they CAN be the same, for a life of argument, difficulty and slave to a keyboard, guns at 20 paces....Relay and Solenoid are different devices for different design and implementation. "barrel" type relays bring confusion and much hand wringing i fear....a smile here.

FWIW was apprenticed in the telephone exchange era, stagger by stagger to CrossBar, relays, were relays in dem days, who knows how many in an exchange, many thousands if not multiple hundreds of thousands of relays, with up to 36 contacts per relay.... as the robot in hitch hikers guide to the galaxy.... " relays....dont talk to me about relays..... moan..." j
 
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