'79 XS650 Build project.

Jim

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You're doing a process of elimination. Eliminate something, see if the problem goes away/changes.
If everything else is eliminated and the light still flashes, the M-units the culprit.
If something you eliminated is the culprit, you'll have to solve for that. But first you gotta know what the culprit is before you'll know how to correct it.
 

2BallCane

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Update: disconnected the PMA, the light still flashed. I disconnected the ignition wire, still flashed.

It flashes when I press the starter button. Can't tell if it happens when I kick start it because I can't see it under the seat.
 

Jim

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Tells me it's inside the M-unit. Guess you'll need the factory to clarify why it's flashing... and whether or not it's a fault in the box.
 

2BallCane

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Right now the bike doesn't want to start, not sure why. It's got spark, fuel, and compression. Maybe the floats are stuck up and not letting fuel into the bowls. I'll figure it out later. I have schoolwork to do.

As far as the M-Unit goes, everything works, and hopefully Motogadget gets back to me sooner than later.
 

2BallCane

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Received word from Motogadget. Here's what they said.

"Thanks for reaching out! I would be more than happy to help you.

If you increase the rpm and the bluetooth light is flashing means that you have high emc or your connection between the mo.unit and your battery has loose contacts. Make sure the connecting between the mo.unit and the battery is solid and no grime on the connections. Otherwise, the battery will not eat the voltage spikes.

Please let me know if I can answer any more questions, and I'd be happy to help!

Kind regards
Kim
motogadget Support Team"

So, I thought that I had solid connections, but I guess the vibration from the bike loosened them up. So I'm going to have to go through then and maybe use the impact driver to make sure they're tight. I'm also expecting a battery strap, so hopefully that will keep the battery from moving too much.
 

2BallCane

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So looking back, it makes sense as it would only happen when the bike made sudden movements. I'm glad it's a simple fix. I'll just have to trim up the insulation around the connections so they sit flat and firm on the battery. I don't know if I should use medium strength loctite or not.
 

650Skull

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Should never need to use an impact driver on battery terminals. In fact it is not something to ever do. Your putting stress on the battery where the terminals connect to the battery and this could cause the battery to crack.

I have never had trouble tightening cables to bike batteries using a screw driver and never had to use any lock tight. I use Lanolin grease on my terminal screws to stop corrosion and it is also act's as a locktight.
 

teamWicked

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Should never need to use an impact driver on battery terminals. In fact it is not something to ever do. Your putting stress on the battery where the terminals connect to the battery and this could cause the battery to crack.

I have never had trouble tightening cables to bike batteries using a screw driver and never had to use any lock tight. I use Lanolin grease on my terminal screws to stop corrosion and it is also act's as a locktight.
Anyone looking for lanoline, +90% pure, look no further than the Walgreens nipple health section. Lifetime supply for ~$10.
 

650Skull

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So looking back, it makes sense as it would only happen when the bike made sudden movements. I'm glad it's a simple fix. I'll just have to trim up the insulation around the connections so they sit flat and firm on the battery. I don't know if I should use medium strength loctite or not.

Here is a lanolin product that can be got in the US.

https://www.fluid-film.com/

As i pointed out earlier using a lanolin grease product also acts as a locktight
 

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2BallCane

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So I went back, trimmed any insulation that may be hampering the connections, and ensured they were nice and tight. It's still happening, which according to Motogadget, means I have high ECM, which, quite frankly, I have no idea how to remedy. Also, I don't know where the ECM is coming from because I disconnected the PMA altogether, and it still happened.

The M-Unit is more than the recommended distance from the spark plugs, but it did mention utilizing a resistor plug. I have the plugs on hand, but the spark is weak in comparison to the OEM plugs. I haven't tried to use them yet. But again, it only happens when I rev the engine, or use the starter. So not sure if the plugs are the problem because they're constantly sparking, not just when I rev it.

Meanwhile, Revival cycles got back to me and said

"It's not an issue. It's just indicating that the mo.Unit is active.

Best,

Jeff
Revival Cycles / The Handbuilt Motorcycle Show"

Kinda stuck between a rock and a hard place. I would assume the manufacturer knows better, but the question is, what do I do?
 

2BallCane

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UPDATE!

I solved the problem. It WAS the spark plugs. I switched out the BP7ES for BR7ES (Resistor type equivalent) and no matter how much I revved the engine or used the starter, it didn't flash as it did before.

So if anyone has the same problem, pay attention to the M-Unit manual, because it does state that resistor type spark plugs are required.

Now I just need to get my timing correct. The timing is too advanced right now. Going to have to get that figured out (HHB PMA).
 

2BallCane

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So now that the M-Unit issue is resolved, I bought a piston stop to help find true TDC. I kinda eyeballed it before, and the bike runs fine, but the timing is too advanced at idle. So I'm going start by making sure TDC is correct and then adjust the valves accordingly, then once proper timing is achieved, I'll then try synchronizing the carbs by vacuum. Right now they've been synced using 1/8" drill bits. I also finally got my new front brake line in for the shorter handlebars. So I after all the above is completed, I should be good to go!
 

2BallCane

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So, I got the piston stop to find true TDC, but it's a bit long, so when I try finding it, I rotate the engine back and forth to mark the two spots, and split the difference to get TDC. However, I did that and because the stop is a bit long, the two points are a bit far apart, but that's not that big a deal. The problem is that when I marked it, it's nowhere near my old mark, and it's still not close to where it should be. Meanwhile, I rode the bike around the yard today to test it out, and it runs fine.


Aside from that issue, I put a new brake line on and now the front brake seems a bit tight. The line is completely flushed with brand new DOT3, I cleared the gunk from the caliper. The brake works but the lever moves very little and is tight. Did I bleed it correctly, should I remove the caliper to make sure it moves freely?
 

2BallCane

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UPDATE: I took the timing tab off the PMA and brought it to work to machine the slots a bit longer to retard the timing. I did that, and it doesn't seem much different. I did notice that when I turn up the advance on my timing light, the timing goes back from advance to where it's supposed to be.

At this point, I don't know what to do. I just want the timing to be correct and the carbs synced before I put it on the road.
 

2BallCane

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ANOTHER UPDATE!

I know you guys are just thrilled to hear about my updates. I got everything together and buttoned up, bike is insured and registered. So last night I took it for a quick spin a mile and back, and it went great..... With the exception that I did not, in fact, button everything up. When I returned, I noticed my right side cover was missing. So I went out and found it in the road, only to realize that I was too late.

So long story short, I need a "new" side cover.
 

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