need a new 1979 Yamaha MAIN SWITCH ASSEMBLY

[jun8ior]

Hello,

My switch has been flopping around for a while, but now it is affecting ignition and general running.
If I turn the bike on, the lights start, but the ignition switches button (on handlebar) won't have any effect until I lift the switch assembly upwards.

Once it has started, I can release the assembly.

However, while riding, if I give it more gas it starts to sound like it is only firing on one cylinder.
This all happened at the same time so I very much doubt that the firing effect is related to something else (spark plug etc).

I have run the local Yamaha dealers parts people and had a look online.
I've only found one out there that is on EBAY.

Does anyone else know where I could locate a new one, or is it at all possible to fix it?

Here's a google photos library video of the above scenario:

https://photos.app.goo.gl/2AtqjrZ2pDvejSJy6

In addition to the ignition not working when in the lower position, there is a clicking noise when I move the assembly up and down. It sounds like a solenoid to me but I am NOT a mechanic.
On top of that, the cylindrical section that I am pressing has also been making that same solenoid click sound (I think this is an actual solenoid) so, if it is clicking when pressed, could this also be an issue??

I'll come back and see if I can explain it better.

Cheers!

 

[jetmechmarty]

Who is your favorite purveyor of vintage motorcycle parts? Many of them have this. Since it was designed to be up front and oriented differently, perhaps a different replacement might prove superior?

 

[jetmechmarty]

What is that switch mounted to? I can't really tell if the whole assembly is moving.
Look here:
https://www.lowbrowcustoms.com/pages/search-results-page?q=ignition+switch
Maybe something there is better.

 

[DogBunny]

I suspect that your flopping switch has caused one of the wires on the back of the switch to become detached at the solder button. When you lift the switch, you re-make the connection. Those switches are pretty easy to take apart to get to the solder buttons, and it is pretty easy to re-solder them.

There are plenty of brand-new switches on eBay:
https://www.ebay.com/sch/i.html?_fr...sacat=0&LH_ItemCondition=3&rt=nc&LH_PrefLoc=3

Once you get it fixed, secure your switch so that it doesn't flop around so that it doesn't happen again.

I think your firing on one cylinder issue is completely unrelated.

 

[jun8ior]

What is that switch mounted to? I can't really tell if the whole assembly is moving.
Look here:
https://www.lowbrowcustoms.com/pages/search-results-page?q=ignition+switch
Maybe something there is better.

Hey,

I'll upload a better photo. It is mounted to a pretty thick plate, lots pretty legit...
I'll take it off when I get the proper tool and see if I can solder it. Much better idea than replacing it.

 

[sleddog83]

That does sound like a solenoid kicking in. That shouldn't be happening just by turning the ignition switch on. You could figure out which one is engaging by touch. Put one hand on the relay while switching the key on. I don't have the 79 schematics with me at the moment, but imagine there are more than a couple of relays: starter, starter lockout,.... Starter relay would seem unlikely. Probe around by touch and use your ear.

 

[jun8ior]

Here are photos of what it is mounted to. The bolts are tight, its just the main cylinder that is loose so I'll remove it and see if I can secure it again,

 

[DogBunny]

Looks like you're missing one of the two small Phillips screws that attach the bottom plate to the main cylinder. The remaining screw is probably loose. Remove the existing small screw, open the little cable clamp, and you'll see where the wires are soldered.

 

[jun8ior]

Looks like you're missing one of the two small Phillips screws that attach the bottom plate to the main cylinder. The remaining screw is probably loose. Remove the existing small screw, open the little cable clamp, and you'll see where the wires are soldered.

Ahh, your eyes are better than mine!
Yeah I can see that now, I'll follow your instructions, then see if I can find a matching screw.

Cheers!

 

[5twins]

It looks like you have a regular Special ignition switch assembly there, just mounted in a different location. These are the screws you're missing one of .....

They hold the black lock cylinder housing tight to the base and the contact plate .....

I don't think you have any broken wires, you're just losing contact with the contact plate because the black lock cylinder housing is loose and flopping around.

 

[jun8ior]

It looks like you have a regular Special ignition switch assembly there, just mounted in a different location. These are the screws you're missing one of .....

They hold the black lock cylinder housing tight to the base and the contact plate .....

I don't think you have any broken wires, you're just losing contact with the contact plate because the black lock cylinder housing is loose and flopping around.

Excellent.

Thank you for this!

 

[jun8ior]

Hello,

So, the missing screw was the cause of the loss of connection.
However, while putting it back together a section (1.jpg) popped out, now once put together, the key won't rotate as before. (the power will connect if you rotate the key in the opposite direction, but its not put together properly)

I can see from 5twins photo that I have got the copper plate from image 2.jpg & 4.jpg upside down, but am convinced that the copper section with a tooth is loaded incorrectly.

 

[jun8ior]

I tried it in this position but that didnt work, and because at least in my mind, if the plate was rotated with these teeth aligned, how could it rotate?

If anyone could help out with the alignment for 5.jpg, that would be amazing.

Cheers

 

[DogBunny]

I don't know exactly what's wrong with how you have assembled yours, but maybe this will help. Your switch has three positions, off, on, and lock (steering lock). There is a sort of like "bolt" that comes out when you put the switch in the lock position. The bolt is otherwise flush, but you should be able to see it. To use the lock, you start in the off position, and then PUSH THE CYLINDER IN while turning Counter-Clockwise. You can only push the cylinder in when the teeth are lined up.

 

[5twins]

Yes, you had the detent plate in upside down. The extrusions or "bumps" should face up .....

I've never seen a bottom part in metal like yours. All the ones I've dealt with were white plastic. They were pretty much shaped the same though, only difference being they don't have that notch. No matter, yours is installed wrong. Here's how it should look with the key in the "OFF" position .....

..... then with the key rotated all the way in the counterclockwise direction to the "Park" position. You can also see this activates the steering lock pin .....

 

[5twins]

I also see you put it all back together dry. Moving parts should be lubed .....

 

[jun8ior]

Yes, you had the detent plate in upside down. The extrusions or "bumps" should face up .....

I've never seen a bottom part in metal like yours. All the ones I've dealt with were white plastic. They were pretty much shaped the same though, only difference being they don't have that notch. No matter, yours is installed wrong. Here's how it should look with the key in the "OFF" position .....

..... then with the key rotated all the way in the counterclockwise direction to the "Park" position. You can also see this activates the steering lock pin .....

Thanks for all the help.

These photos helped a lot. I had to hold the rod with nose pliers then place the circular plate into the correct position.

Cheers,
M