Does not starts in gear

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gspd
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I see your problem, said the blind man

Post by gspd »

The yellow/brown wire from your clutch switch is routed directly to ground and it shouldn't be.
Basically, your clutch switch is just connecting a ground to a ground.
In other words... it's doing nothing.
We'll find out why in the pics tomorrow.
Mechanic from Hell
"I remember every raging second of it...
My bike was on fire, the road was on fire, and I was on fire.
It was the best ride ever!"
Rob Frankham
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Re: I see your problem, said the blind man

Post by Rob Frankham »

gspd wrote: Sat May 01, 2021 9:59 pm The yellow/brown wire from your clutch switch is routed directly to ground and it shouldn't be.
Basically, your clutch switch is just connecting a ground to a ground.
In other words... it's doing nothing.
We'll find out why in the pics tomorrow.
My apologies for butting in but I think you are making an invalid assumption there.

If the brown/yellow wire were to be permanently connected to ground, the starter would engage whenever the button is pushed whether the clutch was pulled or the gearbox in neutral; or both... or neither. The whole clutch interlock system would be bypassed.

The reason there appears to be a connection to ground on the brown/yellow wire is that current can flow through the diode to ground via the neutral switch... or... if the box is in gear, provided the test light is a low wattage bulb and the ignition is switched off, the test light will see a 'virtual ground' via the neutral light and the rest of the bikes wiring.

Assuming the symptoms are stated accurately in the first post on the thread, the fault must be a break in the circuit between the brown/yellow connection on the connection board in the headlamp shell and ground via the clutch switch.

Since the clutch switch itself has been shown to be probably good, then this leaves the brown/yellow wire and the brown wire from the clutch switch.

Since we have seen battery voltage at the clutch switch, the brown/yellow wire is almost certainly good, This leaves the brown wire connection.

To my mind, the simplest diagnosis would be to-

A) make a jumper wire and connect the brown/yellow wire at the connector direct to ground. Switch on the ignition and try the starter. If it works, the circuit is proved as far as the connector. If it doesn't, the fault is in the brown/yellow wire from the connection board to the twin connector.

B) use a jumper wire to connect the brown/yellow wires in the connector to the brown/yellow wire from the switch. Use another jumper to connect the brown wire from the switch to ground. Does the bike now start with the clutch pulled. If it does, the switch is proven good and the problem must be in the brown wire connection to ground. If it doesn't, then the switch, despite all that has gone before, is defective... yes, I know it's new and has passed the 'multimeter test' but that isn't definitive.

Two simple tests and you have a definitive indication of where the problem is... no test equipment needed beyond a couple of lengths of wire and, because the test results are indicated by the operation of the ciruit you are testing, you can be sure that 'good' and 'bad' mean exactly what they say

Rob
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gspd
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Re: I see your problem, said the blind man

Post by gspd »

Rob Frankham wrote: Sun May 02, 2021 5:56 am
gspd wrote: Sat May 01, 2021 9:59 pm The yellow/brown wire from your clutch switch is routed directly to ground and it shouldn't be.
Basically, your clutch switch is just connecting a ground to a ground.
In other words... it's doing nothing.
We'll find out why in the pics tomorrow.
make a jumper wire and connect the brown/yellow wire at the connector direct to ground.
We've already established that the clutch switch is doing that.

Everything you (Rob F and Seth) said is plausible, but for cpazambrana, it probably sounds like chinese.
I understand everybody is trying to help cpazambrana, but from his own admission, he knows very little about electrickery. Everybody needs a chance to learn. This is his.

The problem (not starting in gear) can be fixed in a few minutes with a few strategically placed sections of wire and a diode from my junk box (so the neutral light doesn't turn on every time the clutch lever is pulled in) but I prefer getting right to the source of it and correcting it properly so the next guy who works on the bike doesn't detect any (more) bodging.

I'm trying to keep things on an very elementary level to facilitate cpazambrana's comprehension of the problem.

We've already established that the brown/yellow wire from the clutch switch is going straight back to ground instead of going to the other brown/yellow wire on the circuit board. Might be a short, a corrosion bridge or break in the board, a wrongly connected wire from previous bodging or a first time something else never previously encountered by anyone.

Anybody here is welcome to take over this tutorial; I personally can do nothing more without, at the very least, visual access to the circuit board. Can anybody here do more? if so, please go for it.

That's why I'm waiting for pics of the circuit board. From there I can walk cpazambrana through the remaining test procedures.
I will be able to make it simple for him by sending him his pics back with arrows pointing to the exact terminals or wires to test, jump, bypass, eliminate, etc.
Mechanic from Hell
"I remember every raging second of it...
My bike was on fire, the road was on fire, and I was on fire.
It was the best ride ever!"
cpazambrana
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Joined: Wed Apr 14, 2021 12:59 pm

Re: Does not starts in gear

Post by cpazambrana »

Guys. I’m sorry to be replying this late. I’m a single father and my week with my girls starts today. However I took out the headlight and took a look at the board with the colored terminals. The cable that was coming from the start switch was misplaced. This thing is color coded to match the cables and someone put the brown/yellow wire in one of the blue yellow terminals. I put it in the 85b (which is brown/yellow) and the bike started right away both in neutral and in gear with the clutch pulled in. Everything now works as it should. I was a bit afraid to fry something but it seems to be working now. Since I was already there I checked the cables with tape. Most of them were good and most of the tape were markers or put there to identify the wire. I appreciate all of your help in sorting this thing out. Like gspd said it was something easy to fix. I hope that if someone out there goes through the same thing, can read this and get it fixed too. If you think I should be looking at something else please feel free to let me know. Again, thank you!
1983 BMW R80RT
1976 BMW R60/6
Still looking for a Honda CB77 Superhawk
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gspd
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GSPD had premonition

Post by gspd »

Your welcome dude! Now you know why I needed pics to proceed.
Glad it was that obvious and open heart surgery (on the circuit board) was not necessary.
Post back if you have any other problems.
It gets kind of boring here sometimes.

BTW- just for the record...
At 1.12 pm I wrote this to Rob F in a PM, we were discussing this problem.
One of my theories was...
The clutch switch wire may have come off it’s terminal at one point and have gotten reconnected to a brown terminal instead of its proper brown yellow terminal.

At 4.28 pm cpazambrana posted on the forum…
The cable that was coming from the start switch was misplaced. This thing is color coded to match the cables and someone put the brown/yellow wire in one of the blue yellow terminals. I put it in the 85b (which is brown/yellow) and the bike started right away both in neutral and in gear with the clutch pulled in.

The previous tests, and similar past experiences, were pointing me in that direction.
How much closer of a diag can you get without actually seeing the thing?
Do I know old bodgered airheads or what?
Mechanic from Hell
"I remember every raging second of it...
My bike was on fire, the road was on fire, and I was on fire.
It was the best ride ever!"
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melville
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Re: Does not starts in gear

Post by melville »

I useta tell people who called the bicycle shop where I useta work, "Bring the bike a little closer to the phone."
Call me Mel. Some years ago- never mind how long precisely- having little or no money in my purse, and nothing particular to interest me at home, I thought I would ride about a little and see the other parts of the world.
cpazambrana
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Joined: Wed Apr 14, 2021 12:59 pm

Re: GSPD had premonition

Post by cpazambrana »

gspd wrote: Sun May 02, 2021 6:12 pm Your welcome dude! Now you know why I needed pics to proceed.
Glad it was that obvious and open heart surgery (on the circuit board) was not necessary.
Post back if you have any other problems.
It gets kind of boring here sometimes.

BTW- just for the record...
At 1.12 pm I wrote this to Rob F in a PM, we were discussing this problem.
One of my theories was...
The clutch switch wire may have come off it’s terminal at one point and have gotten reconnected to a brown terminal instead of its proper brown yellow terminal.

At 4.28 pm cpazambrana posted on the forum…
The cable that was coming from the start switch was misplaced. This thing is color coded to match the cables and someone put the brown/yellow wire in one of the blue yellow terminals. I put it in the 85b (which is brown/yellow) and the bike started right away both in neutral and in gear with the clutch pulled in.

The previous tests, and similar past experiences, were pointing me in that direction.
How much closer of a diag can you get without actually seeing the thing?
Do I know old bodgered airheads or what?
Lol. Now the only thing left is to correct a very slow leak in the driveshaft boot. I put a temporary solution which has work as of now using RTV silicone. But eventually I will need a new boot.
1983 BMW R80RT
1976 BMW R60/6
Still looking for a Honda CB77 Superhawk
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