BS 34 carburetors

One had a fractured plastic part to the right picture lowest
the one with no key positions
The other one is bent downwards but had key positions
Perhaps epoxy glue and a support plastic piece.
Some thinking to do
If what plastic is known and what glue is best perhaps even melting it together please tell

The copper dots is pitted at 5 o clock on the one at top upper picture
the other one is worn but more evenly.

3 small springs is there pressing up a copper piece towards the copper dots in the picture .But springs looks OK

The plastic part I believe is the Main Issue.





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I've never seen a plastic part or switch plate like those. Must be a "Euro" switch? You can mix and swap parts. I'd take the best from both and try to make one good one.
 
I've never seen a plastic part or switch plate like those. Must be a "Euro" switch? You can mix and swap parts. I'd take the best from both and try to make one good one.

Thank you Sir
Need to think this ower .. It is a fair chance that the one installed in the bike is the same design. And the plastic have aged even if I can glue it or reinforce in some way. There is the risk for problems again.
I can buy a standard lock from an automotive shop for $ 10 that is new and looks OK
Or buy a new lock Yamaha style a $ 30 from e-bay in Germany.
 
Bypassed Yamaha Ignition lock ..believing it had problems with a brand new one
No success

0.6 --1 V voltage drop when switched on Seems to high
Please feel free comment .. Battery ?? Even though it has correct Voltage ??

After rethinking ill probably start removing fuses to se if any change localize what circuit.
And servicing other wires.

IMAG0068.jpg



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Nothing to do with carburetors but put i here as method for Fault Finding Perhaps helpful
2 Ignition switches check
Battery is a pass check

Started to take out fuses one at a time to figure out what circuit -- no change
Then i removed all of them except main fuse still no change
Still a voltage drop scratching my head how is that possible ?

By looking at the schematic for my 1980 XS 650 SE US Custom

The power comes from the battery to the ignition switch and then returns to the rest of the fuses 3 more .
But these were not there
But on that wire Brown there was a split so it also went down to the Voltage regulator

When I pulled out that brown on the regulator the voltage drop disappeared

So I am now at downstream from that
Regulator / Rectifier / Alternator with two big connectors
And a DIY wiring " Birds nest " Then it started to rain

Giving time to Think again I have a spare regulator that I can plug in.
And a spare rectifier.
Thinking
 
New rain shower

Rectifier is out on the bench -no change still voltage drop
Splitting the connector going down to the alternator .. Voltage drop disappears
Cleaning that connector it is dirty ..but not so much that I believe its there
lets se .. and put it together and then onto the brushes and rotor
 
Just to clarify Jan, there's two types of voltage drops....

1. Battery voltage will drop across the entire system when turned on. A drop of 1 to 1-1/2v is not unusual. In other words, pretty much normal.

2. Voltage drops across a component that's supposed to have no (zero) resistance, such as a switch or connector. An example would be the iggy switch.... say the battery voltage is 12v at the battery (and going into the switch) but only 11v coming out of the switch. This kind of voltage drop is not normal nor acceptable.

Bara för att förtydliga Jan, det finns två typer av spänningsfall....



1. Batterispänningen sjunker över hela systemet när det slås på. Ett fall på 1 till 1-1/2v är inte ovanligt. Med andra ord ganska normalt.



2. Spänningsfall över en komponent som inte ska ha något motstånd, till exempel en strömbrytare eller kontakt. Ett exempel skulle vara iggy-omkopplaren.... säg att batterispänningen är 12v vid batteriet (och går in i strömbrytaren) men bara 11v kommer ut ur strömbrytaren. Denna typ av spänningsfall är inte normalt eller acceptabelt.
 
Splitting the connector going down to the alternator .. Voltage drop disappears
Most likely that's the rotor. At about 5Ω, it's drawing about 2.5amps. That will definitely draw the battery down a bit.
 
Worked my way Down..
Had sub 10 V on the Brush at the alternator
Disconnected the green on the Brush no voltage drop on power on
Measured 4.8 Ohm on the slip ring resistance. Looks right. Please tell if OK
Need to think again .
Perhaps checking with another regulator.
Perhaps leave as is charging has been fine last couple of years
So with serviced connectors assuming The Boyer gets what it needs

And move the needle as per 5 T #36

Just to think out loud
??? Disabling the rotor feed at kick starting having 12.5 ish instead of 11.8 into the Boyer getting better startup and then switch on the charging ??

Need to think again .
But you can be right Jim .. Tightening up the electrics ... serviced .. Go for a test-ride and then if there is need move the Needle
 
Just to think out loud
??? Disabling the rotor feed at kick starting having 12.5 ish instead of 11.8 into the Boyer getting better startup and then switch on the charging ??
This will disable it with electric start. I suppose you could just use a pushbutton on the handlebars....

https://www.xs650.com/threads/53271
 
This will disable it with electric start. I suppose you could just use a pushbutton on the handlebars....

https://www.xs650.com/threads/53271

Thank you Sir
I will read that .. If this is typical the alternator is energized with 0.5 -1V Voltage drop that can kick down the overall system Voltage to
Sub 11 ..s V to mid 11 -s especially with poor battery and poor wiring.
That makes starting difficult ( more difficult ) with especially points and electronic.
I have a sneaking suspicion that my Bosch type regulator can push excess. Current through.

But I have one wire feed the brown already accessible into that regulator I just cut it and insert a switch
If I get this right
Simplest mod ever
And with a voltmeter on the bike one wont forget it --- if so it sooner or later reminds you

It comes down to if there is any risk energize the alternator while it runs rather than is still
Spikes and sparks Again not thought through fully.
 
After having low Voltage at Alternator supply

I went upstream and pulled out the regulator -- the black one center
I have it where the bike tools should be
It was turned so there was like a cup and had water in it. Reading 11. 8 V at alternator
Connected a stock relay type regulator plugged in getting 12.2 V at alternator supply

So it points at the Regulator it has 12.5 in but drops it to the 11.8 dont know if it is the water . i think I could se a crack
Have other electronic ones .but need to figure out which pin goes where so I dont fry it





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Which charging system version do you have? The older type with the grounded inner brush or the later type with the powered inner brush? U.S. bikes got the later version in 1980 but your U.S. Custom model may still have the older type. The type of charging system you have will determine what kind of regulator you need, a ground regulating type "A" or a power regulating type "B". If you show us a pic of your alternator and brushes, we can tell you which one you have.
 
Which charging system version do you have? The older type with the grounded inner brush or the later type with the powered inner brush? U.S. bikes got the later version in 1980 but your U.S. Custom model may still have the older type. The type of charging system you have will determine what kind of regulator you need, a ground regulating type "A" or a power regulating type "B". If you show us a pic of your alternator and brushes, we can tell you which one you have.


Thank you Sir I have the older type ( I believe . pretty certain )
Charging has been fine ..I have a Voltmeter connected
No problems with charging the last 3 years
A little difficult to start but that is nothing new to me.

Not sure if it can be seen on the picture with brushes out For service and cleaning -- taken out of the equation.

I did find another automotive 3 pin + ground regulator
( Wood auto UK )

Same Result 12. 3 in on regulator dropping to 11.8 at the brush wire Alternator end open not connected
Pulled it and connected the stock one again + 12.2 on Alternator wire end open not connected

Am I using the wrong regulators dropping to much .. Might have been this way all the time.
But difficult to start has almost always been a problem and charging been better than ever last 3 years.

Need to think again an obvious way is to service the stock one see what happens test-riding
Its just plugs in ..

Might not have anything at all to do with the stumbling Once the bike starts there is + 14 V






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Yes, you have the older style alternator. I can tell because of the one large cut-out for the outer brush and the cast-in timing marks. The later alternator has two large cut-outs and the timing marks are on a detachable plate. Here's the two compared .....

AlternatorHousings.jpg


So, you will need a type "B" power switching regulator.
 
Nothing conclusive on the Voltage drop --assembling
It is the regulator that drops it
But since charging been fine
Going now for the automotive electronic regulator metal casing ev with a bypass switch for starting further on
Plan B --stock regulator
Since nothing in the electrics leaning out the needle it is already second from top
going for the top 1 slot if this seems wrong please tell


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Your alternator has been charging, but that doesn't mean that the charging system is "fine." One great virtue of the OE breaker point regulator is that it is adjustable. If you don't have a decent manual, go to www.biker.net and download the electrics section of the 1978 factory service manual. Clean points and adjust air gaps first, then try to bring charging into spec range with the output screw. I haven't found an XS650 breaker point regulator yet that didn't respond to service.
 
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