50V Moby no spark or lights and decompressor question

Kyle Osborne /

So I recently got a Moby 50V ($80CAD and 95% of it is there) it's a 6volt one (Judging from the wiring diagrams I've seen)

But I"m having spark issues....I've searched for solutions, but haven't found anything...I heard that the killswitch can cause issues as well as not having a working bulb in your lights. how can I by pass the lights and/or kill switch to find the problem? My dad seems to think it may be the transformer coil or a coil in the magneto...how can I test to see if it's the transformer coil that's not working? I tried testing for continuity, but I didn't get anything.

From what I can tell, all the wiring is there...and according to the wiring diagram I have, it's missing a green wire going form the transformer coil to the engine kill switch....the only wires on the transformer coil are a grey wire the spark plug wire and a bare wire around the mounting bolt of the coil and goes to the cylinder head...

As for the decompressor question...my Moby has an integrated twist throttle and decompressor? But it looks as if the decomressor lever is missing....the cable is there but I don't know what or if it's connected to anything on the handlebar.

Re: 50V Moby no spark or lights and decompressor question

well a voltage meter would be helpful. also if you put up some pictures of the decomp situation you have.

Re: 50V Moby no spark or lights and decompressor question

Look on the back of the genny - single spade terminal=6volt, black plastic with two terminals=6/12volt.

6 volt will run with no accessories attached, you just need the gray wire from the genny to the external coil. but you better fix the decompressor or you have to shut her down by pulling the plug wire.

6/12volt with three coils inside the genny will run with accessories disconnected

6/12volt with two coils inside the genny needs to have an accessory attached to the 12 volt or that terminal grounded because it is the other end of the winding for the ignition coil.

Is the spark robust and snappy or yellowy and weak? Might need to change out the condenser, Get a 1960s GM 6 cylinder condenser and mount it beside the external coil. Disconnect the old one inside the genny and connect the pigtail from the new one to the gray wire.

Make sure you have a good bonding strap between the external coil and one of the intake studs.

Re: 50V Moby no spark or lights and decompressor question

Kyle Osborne /

Probably not the best angle, but it's just what I had on my PC at the moment...

I also have a voltmeter/multimeter on hand.

decomp.JPG

Re: 50V Moby no spark or lights and decompressor question

Kyle Osborne /

Rebel Moby Wrote:

-------------------------------------------------------

> Look on the back of the genny - single spade

> terminal=6volt, black plastic with two

> terminals=6/12volt.

>

> 6 volt will run with no accessories attached, you

> just need the gray wire from the genny to the

> external coil. but you better fix the decompressor

> or you have to shut her down by pulling the plug

> wire.

>

> 6/12volt with three coils inside the genny will

> run with accessories disconnected

> 6/12volt with two coils inside the genny needs to

> have an accessory attached to the 12 volt or that

> terminal grounded because it is the other end of

> the winding for the ignition coil.

>

> Is the spark robust and snappy or yellowy and

> weak? Might need to change out the condenser,

> Get a 1960s GM 6 cylinder condenser and mount it

> beside the external coil. Disconnect the old one

> inside the genny and connect the pigtail from the

> new one to the gray wire.

> Make sure you have a good bonding strap between

> the external coil and one of the intake studs.

there's 3 wires from the genny, a brown and a black one and the grey one that goes to the coil..and it has 2 coils inside...and looking at the wiring diagram again, I"m guessing that's what i need to do, is ground the black wire, from the ignition coil.

Thanks.

Re: 50V Moby no spark or lights and decompressor question

This is a picture of the under side of the throttle with which screw is for which component. Also a picture of the double cursor.

Look on the front of the engine cylinder head, there is a valve which should have the decomp cable attached to it.

ThrottleUnderside.JPG
IMG_9786.JPG

Re: 50V Moby no spark or lights and decompressor question

Kyle Osborne /

Rebel Moby Wrote:

-------------------------------------------------------

> This is a picture of the under side of the

> throttle with which screw is for which component.

> Also a picture of the double cursor.

> Look on the front of the engine cylinder head,

> there is a valve which should have the decomp

> cable attached to it.

Yea I seen that, so does the decompessor work with the twist grip of the throttle?

but that's exactly what I have that you posted in those pics.

Re: 50V Moby no spark or lights and decompressor question

♣Slew Foot♣ /

the lever under the handle squezes the loop by forcing it closer to the barrel end holder on the base of the valve it has a split to get the barrel end in so that when it is pulled it pushes the loop pushing the needle cam valve in.

Re: 50V Moby no spark or lights and decompressor question

If you twist the throttle backwards it should open the decompressor, making it easier to start the bike, also it works as a means to stop the bike.

How to start -

Open the fueltap

Turn the master switch from hell to RUN

Give a little choke

Counter rotate the throttle

One thrust of the pedal and rotate throttle forward

Once running release choke

How to stop -

Counter rotate the throttle

Close the fueltap

Turn the master switch from hell to STOP

Re: 50V Moby no spark or lights and decompressor question

Kyle Osborne /

Ian Grant Wrote:

-------------------------------------------------------

> well a voltage meter would be helpful. also if you

> put up some pictures of the decomp situation you

> have.

I have one, how would I go about testing the magneto and or coil for voltage?

Re: 50V Moby no spark or lights and decompressor question

Kyle Osborne /

Rebel Moby Wrote:

-------------------------------------------------------

> Look on the back of the genny - single spade

> terminal=6volt, black plastic with two

> terminals=6/12volt.

>

> 6 volt will run with no accessories attached, you

> just need the gray wire from the genny to the

> external coil. but you better fix the decompressor

> or you have to shut her down by pulling the plug

> wire.

>

> 6/12volt with three coils inside the genny will

> run with accessories disconnected

> 6/12volt with two coils inside the genny needs to

> have an accessory attached to the 12 volt or that

> terminal grounded because it is the other end of

> the winding for the ignition coil.

>

> Is the spark robust and snappy or yellowy and

> weak? Might need to change out the condenser,

> Get a 1960s GM 6 cylinder condenser and mount it

> beside the external coil. Disconnect the old one

> inside the genny and connect the pigtail from the

> new one to the gray wire.

> Make sure you have a good bonding strap between

> the external coil and one of the intake studs.

I'm taking a guess and saying mine is a strict 6volt system...it's got the IGN coil on top and the Lights one on the bottom as well as a gold round capacitor looking thing on the left side...

and what's a "6/12"? or is that just saying the same thing for a 6volt and a 12volt system? Or are some systems both 12 and 6 volts?

Re: 50V Moby no spark or lights and decompressor question

The '12 volt' Mobys actually have 6 and 12 volt, I refer to them as the 6/12 because too many people ask about the other terminal or the thirs coil or all sorts of clarification anyway.

Re: 50V Moby no spark or lights and decompressor question

Michael Koerber /

wiring diagram for canadian Mobys

Re: 50V Moby no spark or lights and decompressor question

Kyle Osborne /

Rebel Moby Wrote:

-------------------------------------------------------

> The '12 volt' Mobys actually have 6 and 12 volt, I

> refer to them as the 6/12 because too many people

> ask about the other terminal or the thirs coil or

> all sorts of clarification anyway.

ahh, ok so with the 2 coils and the gold capacitor,mine would be a 6Volt only?

Re: 50V Moby no spark or lights and decompressor question

Kyle Osborne /

So I've tested the condensor, it works and I cleaned out the rust in the sparkplug boot and now I get continuity from the end of the spark plug(electrode end) to the connector that fits into the iginition coil....but I'm still not seeing spark....

I also have the black wire from the magneto grounded out on the cylinder head and I have the spark plug itself grounded, and not inside the engine.

Am I missing something?

Re: 50V Moby no spark or lights and decompressor question

Never mind the fancy condenser testing, change it out.

Does the external coil look sort of chalky? then change it out.

Check the internal coils - they should be like 1-2ohm.

The accessory wire has nothing to do with the ignition on a 6v setup. (edited)

Re: 50V Moby no spark or lights and decompressor question

Kyle Osborne /

Rebel Moby Wrote:

-------------------------------------------------------

> Never mind the fancy condenser testing, change it

> out.

> Does the external coil look sort of chalky? then

> change it out.

> Check the internal coils - they should be like

> 1-2ohm.

> The accessory wire has nothing to do with the

> ignition on a 6v setup.

accessory wire? Is that the black or brown one? If it's the brown one I know, if it's the black one coming from the ignition condenser then isn't that leaving the circuit open if it's not grounded or attached to anything?

internal coils in the condensor or the ignition coil?

and I don't have anything to change out the condenser or the ignition coil....but the ignition coil is relatively white looking. I do have another Moby 50v 6volt for parts, but I have no idea if the coil or condenser work on it.

Would dirty points be the cause of my problem?

Sorry for all the questions, lol I just don't know too much about mopeds or the magneto stuff..

Re: 50V Moby no spark or lights and decompressor question

You have two wires then it is not a 6v it is a 6/12v, look on the back of the genny and see on the black connector 6v and 12v.

12v two internal coil you must have the 12v either in contact with the common or have an accessory running on the wire which is in contact with common.

Disconnect everything from the genny and disconnect anything from the gray wire going to the external coil. Connect a jumper from the 12v terminal on the back of the genny and attach the other end to one of the intake studs.

Run a bonding strap from the intake stud up to the lower stud on the external coil.

Attach the gray wire to the external coil with no other wire attached to it.

Check for spark

If you have no spark get a Standard DR60 or equivalent condenser from a car parts store or online. Mount the condenser to the lower external coil stud where you attached the bonding strap. Splice the pigtail from the condenser to the gray wire.

Disconnect the original condenser from the points.

Clean the points with a points file (or metal finger nail file) and flush them with alcohol or brake cleaner (not carb cleaner).

Check for spark.

Re: 50V Moby no spark or lights and decompressor question

Kyle Osborne /

Rebel Moby Wrote:

-------------------------------------------------------

> You have two wires then it is not a 6v it is a

> 6/12v, look on the back of the genny and see on

> the black connector 6v and 12v.

> 12v two internal coil you must have the 12v either

> in contact with the common or have an accessory

> running on the wire which is in contact with

> common.

>

> Disconnect everything from the genny and

> disconnect anything from the gray wire going to

> the external coil. Connect a jumper from the 12v

> terminal on the back of the genny and attach the

> other end to one of the intake studs.

> Run a bonding strap from the intake stud up to the

> lower stud on the external coil.

> Attach the gray wire to the external coil with no

> other wire attached to it.

> Check for spark

> If you have no spark get a Standard DR60 or

> equivalent condenser from a car parts store or

> online. Mount the condenser to the lower external

> coil stud where you attached the bonding strap.

> Splice the pigtail from the condenser to the gray

> wire.

> Disconnect the original condenser from the

> points.

> Clean the points with a points file (or metal

> finger nail file) and flush them with alcohol or

> brake cleaner (not carb cleaner).

> Check for spark.

Ahh, ok so that could be why it's not working, I was troubleshooting it as if it were a straight 6v.....I"ll give this a shot tomorrow. Thanks!

Re: 50V Moby no spark or lights and decompressor question

I did not know the throttle would move the decomp? Did I misunderstand? I pull mine up, give a bit of gas pedal, when engine catches release decomp. Is this not right?

Re: 50V Moby no spark or lights and decompressor question

If you have the lever decomp, then you would pull the decomp and when you are at mid pedal and the motor is turning you would release the lever and add a slight twist in the throttle.

Add a bit of choke to that if the motor is cold.

Re: 50V Moby no spark or lights and decompressor question

Kyle Osborne /

Rebel Moby Wrote:

-------------------------------------------------------

> You have two wires then it is not a 6v it is a

> 6/12v, look on the back of the genny and see on

> the black connector 6v and 12v.

> 12v two internal coil you must have the 12v either

> in contact with the common or have an accessory

> running on the wire which is in contact with

> common.

>

> Disconnect everything from the genny and

> disconnect anything from the gray wire going to

> the external coil. Connect a jumper from the 12v

> terminal on the back of the genny and attach the

> other end to one of the intake studs.

> Run a bonding strap from the intake stud up to the

> lower stud on the external coil.

> Attach the gray wire to the external coil with no

> other wire attached to it.

> Check for spark

> If you have no spark get a Standard DR60 or

> equivalent condenser from a car parts store or

> online. Mount the condenser to the lower external

> coil stud where you attached the bonding strap.

> Splice the pigtail from the condenser to the gray

> wire.

> Disconnect the original condenser from the

> points.

> Clean the points with a points file (or metal

> finger nail file) and flush them with alcohol or

> brake cleaner (not carb cleaner).

> Check for spark.

also, what do you mean by "intake stud" and "lower stud"?

I"m assuming Lower stud means one of the bolts holding the ign coil onto the frame? Or is it something else?

and do I need to take the cover off to do this?

Re: 50V Moby no spark or lights and decompressor question

Kyle Osborne /

So, I got around to picking up a DR60 condenser.....as for disconnecting the original condenser, is that the gold looking thing on the left?

Re: 50V Moby no spark or lights and decompressor question

Kyle Osborne /

Installed the new condenser and disconnected and removed the old one...and now I get spark as soon as I start pedaling!

Gonna see what else I need to do before firing it up..

Re: 50V Moby no spark or lights and decompressor question

EXCELLENT!

Re: 50V Moby no spark or lights and decompressor question

Kyle Osborne /

Thanks for the help and advice.

as for lights...should I just hardwire them, if they're not working?

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