another coil relay gone bad prematurely

[Guest]

Man, all the wiring done here looks so good. Mine looks like crap with a zip tie holding it to the bolt hole where the airbox used to be bolted. New wires for the stator and R/R and now the relay. Looks like some hack got a hold of my bike. It all works great though

[GQROD]

Another thing to consider with the cheap relays especially from Bosch is that they are sensitive to humidity!, in my experience with Porsches these relays would go bad all the time because the humid air inside the car would condense at night, since the ventilation system on these cars was never good and this moisture created shorts which fried the plastic parts inside them.

Since these relays are not water proof they are definetly not going to last too long a motorcycle unless shielded from the elements somehow.

Hope this helps.

[82Shafty]

that's why i didn't cut any wires to install mine. if i have any failure of the relay and i don't have a replacement, i can simply revert the wiring to stock

You and me both brother; always leave yourself a way out!

Worst case I have to lift the tank back a bit and plug in the stock wires and away I go. I'm a big believer in a fail-safe engineering.

[82Shafty]

The three of mine that failed were by the battery box. I tore apart all 3 and on all 3 had the tiny wire connecting the coil the terminal had broken. Vibration killed them. So I spent $100 on a new ignition switch and don't worry about it anymore. And BTW for most models (but not mine) there are cheaper aftermarket ignition switches. I think ~ $30. Might be worth a shot.

I used one of the screws from the fuse box mounts to mount mine.

Mine is a cheapo 40amp Pilot brand from the Zone.

[bakalorz]

It's been a long time since I meddled with electronics at component level but I was pretty sure a thyristor was effectively a switched diode and would operate on DC. I'm also pretty sure you can get them to work at lower voltages as well

But thinking about it you wouldn't really need a SSR you could quite easily knock up a MOSFET (or whatever modern equivalent you can think of) as a simple trigger device with a couple of resistors and you'd have a quite robust solution that would be vibration proof to a greater extent than a relay

The thyristor wouldn't ever turn off.

What you would want is a mosfet (or bjt if you are willing to live with a 0.2 volt loss), but since they invert, you would want to use 2 ... 1 as a driver, and then a 2nd one to do the switching.

when you are done, you have essentially built a SSR ...

[Planecrazy]

Another thing to consider with the cheap relays especially from Bosch is that they are sensitive to humidity!, in my experience with Porsches these relays would go bad all the time because the humid air inside the car would condense at night, since the ventilation system on these cars was never good and this moisture created shorts which fried the plastic parts inside them.

Since these relays are not water proof they are definetly not going to last too long a motorcycle unless shielded from the elements somehow.

Hope this helps.

That's the reason I have advocated using silicone sealant to prevent moisture from getting into the relays. My personal choice would be high temp "gasket maker" because it'll seal just like regular silicone, but will resist any heat buildup that could occur near the contacts.

If one wanted to take it a step further they could use sealant on the contacts themselves (after connecting them, of course) but that would make changing them out a royal pita - not worth it in my opinion.

Regards,

[salty_monk]

Being right next to the battery I very much doubt mine would ever get damp enough to create a problem...

[GQROD]

The silicone makes a lot of sense I will have to try it when i do my coil relay mod.

[BlackStar]

The three of mine that failed were by the battery box. I tore apart all 3 and on all 3 the tiny wire connecting the coil to the terminal had broken. Vibration killed them. So I spent $100 on a new ignition switch and don't worry about it anymore. And BTW for most models (but not mine) there are cheaper aftermarket ignition switches. I think ~ $30. Might be worth a shot.

My experience in failure analysis of aerospace relays is that vibration is the number 1 killer of mechanical relays. Failure mechanism is usually vibration induced mechanical miss-alignment of the armature, contact wear, fod in the contacts, and failure of the coil wires due to improper strain relief during manufacture.
BTW mine is socketed and I carry a spare. I have not hard mounted mine either. Just a tie wrap through the mounting hole.

[don_gibb6512]

Turned out not to be the relay after all. My first test was to swap it out with a good one and the bike started. I swapped it again with what I thought was the bad relay and the bike wouldn't start, so my conclusion was the relay was bad. It was coincidence. Had I tested one more time, the bike wouldn't have started. I disassembled the relay and have attached a couple of pictures. It tested fine and by the looks of it, is very well made. I now doubt that unless these are mounted directly on the engine, they are not going to be effected by heat and it would take a lot of vibration to damage these. The case was very tight and the odds of water getting in is slim to none. IMHO, the relays that are malfunctioning prematurely are most likely manufacturing defects in the relay itself. My problem was (I hope) just corroded contacts on the starter.

[don_gibb6512]

Here is the second picture:

[Texatl]

I mounted my Parts Express relay on the Electrical Panel, I guess I better buy a Spare

Sorry for the slight hijack :-)
Curious???? Whats the switch for behind the pod filter next to the frame rail.

[salty_monk]

Probably a top secret security switch... doh

[Planecrazy]

Probably a top secret security switch... doh

No ... I think it just switches on the light in the garage before he gets there!

Regards,

[Guest]

Sorry for the slight hijack :-)
Curious???? Whats the switch for behind the pod filter next to the frame rail.

Turn signal relay.