Right side switch problems, repair or replace?

[Its been a long time]

Well, yesterday afternoon I got to cranking the motor on my 650 for the first time in my ownership, plugs were out to test for sparks.

Good news and bad news. The starter cranks really well with the plugs out. But two problems have arisen.

Firstly the start button has stuck closed so I have to turn the ignition switch off to stop it cranking. Secondly there's no or intermittent very weak sparks at the plugs.

The right side switch seems to be the cause of both issues. The bottom half of the switch is really crusty, probably been full of water at some time. The top half of the switch is surprisingly clean but the kill switch is very wobbly and the centering detent is there but very weak.

Can anyone shed light on what happens when I remove the screws to look inside the switches? I have sausage fingers and the last thing I need is springs flying out as I disassemble the switches. I am inclined to buy a new switch, they're £50 on Yambits website. Pictures below -

 

[Jan_P]

I have taken it apart many times .Cant remember anything flying out
Once insects had moved in.
I do believe you can save the £ 50
Carefully remove the screws pay attention to what comes out Dont remember if there was a spring and small ball
And service it . Solvent - Tooth brush or soft wire brush and so .--Under the white plastic some service .+ contact grease

 

[Its been a long time]

I have taken it apart many times .Cant remember anything flying out
Once insects had moved in.
I do believe you can save the £ 50
Carefully remove the screws pay attention to what comes out Dont remember if there was a spring and small ball
And service it . Solvent - Tooth brush or soft wire brush and so .--Under the white plastic some service .+ contact grease

Thank you. That's most useful. Can you remember how the kill switch detent works? I need to tighten up the "click" on it. As it is I think a bump in the road could cause me to lose ignition. So it needs fixing as well as cleaning.

 

[Jan_P]

Thank you. That's most useful. Can you remember how the kill switch detent works? I need to tighten up the "click" on it. As it is I think a bump in the road could cause me to lose ignition. So it needs fixing as well as cleaning.

I removed my killswitch many years ago and joined the wires inside Dont have it
After it left me stranded on evening out on a petrol station.

But looking at it there seems to be 3 holes .2 for the wires and I suppose one for a screw from under.
But the rest I cannot remember Sorry

 

[Its been a long time]

I removed my killswitch many years ago and joined the wires inside Dont have it
After it left me stranded on evening out on a petrol station.

But looking at it there seems to be 3 holes .2 for the wires and I suppose one for a screw from under.
But the rest I cannot remember Sorry

That's useful to hear thanks. I did wonder about fitting a seperate kill switch. But the big issue is more the sticky start button really. I 100% need to fix this before thinking about the kill switch. Then, I have to track down for certain why there's very weak to no spark. Could be the kill switch. Could be another problem. We shall see.

 

[Raymond]

I think you just need a nudge to go for it - nothing to lose if plan B is a new switch anyway?

As Jan says, toothbrush to clean. Take it in the house, work on a tray and you won't lose small screws etc. For reassembly, I glue the screw to screwdriver with a blob of grease - saves trying to fit through washers and into the hole with clumsy fingers (mine). I'm not good with fiddly little bits either but it must be good for the soul to learn a bit of patience.

 

[Jan_P]

That's useful to hear thanks. I did wonder about fitting a seperate kill switch. But the big issue is more the sticky start button really. I 100% need to fix this before thinking about the kill switch. Then, I have to track down for certain why there's very weak to no spark. Could be the kill switch. Could be another problem. We shall see.

That is how I do it trying to get spark on substandard wiring .
Short the the kill switch and a separate wire to the ignition box and coil direct After a switch of some sort ( cant leave it on ) maybe after the ignition switch
Most cases it does it and information is obtained if it is Possible to get the spark with correct voltage and so on With the installed ignition
If the spark is there and it does not run it is something else.
Rarely the carburetors 4 - 6 times over close to 40 years and never both sides at the same time.
But I empty the tank every year

 

[Grewth]

Is the Yambits switch genuine Yamaha ?
I'd doubt it unless it actually states genuine, and you'll be paying £50 for a lump of pure Chinesium.
Might work OK for a couple of years, certainly nothing like the 40+ years the original has lasted for.
Have you considered running the ignition feed current through a relay ?

 

[Lou_TX]

If you have contact cleaner, you could also spray plenty into the switch in question and operate it vigorously for a minute or two. Lather, rinse, repeat. As many times as necessary.
The other two solutions are disassembly or total replacement. If you have good eyesight (or magnifying glass), the disassembly can be done easily but carefully. Good advice here. I have cleaned MC switches in the past a few times.
Let us know how it works out, please!

 

[Its been a long time]

Is the Yambits switch genuine Yamaha ?
I'd doubt it unless it actually states genuine, and you'll be paying £50 for a lump of pure Chinesium.
Might work OK for a couple of years, certainly nothing like the 40+ years the original has lasted for.
Have you considered running the ignition feed current through a relay ?

As far as I'm aware, nothing Yambits sell is Yamaha and you're right about quality. I have looked around and found the same pattern switch for £33 now if I need it.

Yes, running a separate fuse and relay to the ignition is 100% on my radar. But first I need to shake the bugs out of what I have. Thanks for the comments.

 

[Its been a long time]

If you have contact cleaner, you could also spray plenty into the switch in question and operate it vigorously for a minute or two. Lather, rinse, repeat. As many times as necessary.
The other two solutions are disassembly or total replacement. If you have good eyesight (or magnifying glass), the disassembly can be done easily but carefully. Good advice here. I have cleaned MC switches in the past a few times.
Let us know how it works out, please!

The contact cleaner route was tried a few weeks ago in preparation for a first start. But on pressing the start button it's stuck in the closed position. So the next step is now on the agenda.

I have no motorcycle time now for a few days so I'll not decide what to do just yet. But at least the options are few in number and clear.

And yes, I'll share progress here. I've had so much support and assistance here, sharing my successes and failures feels like a bit of payback to the community. There's not many places nowadays where you can tap into support like this.

 

[Grewth]

IIRC, Yambits also sell a replacement starter button, for about £8, or at least they used to.
If it's stuck in it sounds like the little coil spring behind the button may have broken and gone coilbound on itself.
Just found it, replacement spring is included

 

[Its been a long time]

IIRC, Yambits also sell a replacement starter button, for about £8, or at least they used to.
If it's stuck in it sounds like the little coil spring behind the button may have broken and gone coilbound on itself.
Just found it, replacement spring is included

Oh, great find. Much appreciated.

 

[5twins]

I think the start button is sticking simply because it's so crusty, lol. Yes, take it all apart and clean and lube it all up. I recently did one just like it to swap onto my '83 (so I could get a headlight on-off switch). Mine wasn't nearly as bad as yours, but it was still in need of a good cleaning ......

You can take the start button apart by spreading it's bracket open to release the the rear contact plate ......

There are two little "nubs" in the housing that the button assembly snaps down behind when installed ......

Notice the dots stamped on the screw heads. That indicates they are the J.I.S. type. The headlight on-off slide switch comes apart in a similar manner. You need to spread it's bracket open a little to release the contact plate .....

I clean up all the metal parts and contacts with the little wire wheels in a Dremel. Plastic parts get cleaned with a plastic cleaner of some sort ......

I use a couple different types of grease when assembling things, regular grease on metal parts, white lithium on plastic to plastic or plastic to metal contact areas. And of course, dielectric grease on the contacts ......

 

[5twins]

You can take the kill switch all apart and clean it as well. Remove the 2 wires connected to it and that will allow access to the 3rd screw, the one that holds it in the housing. I don't think it matters which wire connects to which terminal, but I make a note of how it was connected and re-connect it the same way. Once the switch is out, depress it slightly and remove the little e-clip from it's center post to get it apart.

 

[Its been a long time]

Thank you @5twins. That's absolutely stunning information. I have no time for the next few days but I'm going to have a crack at this.

May I ask, do you know if I can firm up the centre detent "click" in the kill switch? At the moment it's so weak I think a large bump in the road would leave me at risk of losing ignition.

 

[5twins]

It may be just all crusty inside as well. You'll just need to pop it apart and see. Maybe a good cleaning will fix and restore it.

 

[Jan_P]

It may be just all crusty inside as well. You'll just need to pop it apart and see. Maybe a good cleaning will fix and restore it.

Stretching the spring or a New one is also a possibility

 

[Its been a long time]

Stripped the kill switch and starter button out of the right side switchgear this morning. Didn't have far to look to see problems. Obvious that the switchgear has been full of water at some time in the last 47 years.

Kill switch issues are one broken contact spring, one very rusty contact spring and the rusty detent ball stuck in it's hole and not moving. Actual contacts aren't bad. If I can find 2x springs 3.2mm outside diameter and 10mm long, I can fix the kill switch. I think the detent ball will loosen up if I soak it with something.

The starter switch is simply captain crusty due to alloy corrosion debris. Actually is surprisingly good shape. The fixed contact is a bit burnt but will clean up nicely.

I'm off to eBay now to search for a couple of springs that will fit. I have some dielectric grease arriving this afternoon so I'm in pretty good shape I think. Pictures -

 

[Grewth]

Might be worth casting around for another switch to cannibalise for parts.
Quite a few different Yamaha models from that era had the same basic switch body, although the wiring was different.
All the XS250's and 400's had the same switch as well as the generally unloved XS750