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Fuses Blow Wires Burn

2794 Views 3 Replies 3 Participants Last post by  Ray'ssporty1200
Hi all!

I have a Jonway Laguna 250cc ( very basic and a rip off of a Harley cruiser)
I was given this bike from a dear friend for free all that had to be done is some body work and wiring issue.
I've taken it in to the recommended repair guys they sorted the problem for the time. Its been over a few months so i cant send it back.

Issues I noticed

Bike kept dying after I was riding for the day.Had to jump it.
charged battery and everything was fine until the fuse blew out. (it only has one fuse on the whole bike)
after cleaning everything and spraying the bike and changing plugs oil and charging battery, I bought fuses thinking maybe just a fuse issue. Put the same size fuse in and as soon as it touched the fuse holder poof the fuse blew. Tried higher amp same thing even higher same thing then place one fuse in and wire starts sizzling and burning right there in front of my eyes. so had to cut the wire. I would like to know what can i do to sort this issue out and what is the issue

It is a fairly simple bike

head light
tail light
signal lights starter and controls
so im not sure what the problem could be.

I tried many days looking for owners manuals and shop books and nothing.

picture Attached isn't my bike just a look at what the bike looks like


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That's actually a nice looking bike!

It sounds like something is shorted out pretty badly, probably involving something in the circuit which uses the burning wire. You'll have to determine which that is, but I would start there.
You are right CmonStart, too bad it's not his, I saw it and I'm thinking 'That's a cool looking ride.

Well, anyways back to business here !Neels, what were you thinking of ? When you put the first fuse in and it 'blew'
why would you put in a higher amps fuse? o.k. no ones mad here, I'm not but Neel, a fully charged bike battery can
cook a bikes wiring very quickly, you may have seen this recently. When the 1st fuse 'blew' was it darkened, It
probably was, that means a 'short circuit. If fuse blew but not darkened or blackened, meaning you can see the link
had melted, that was an overload. You say you charged battery and things were good till the fuse blew. What were you
doing when the fuse blew?

Here is how this works, Say the headlight, tail lite and brake lite all working, draw 6 amps, so the bike builder fuses that
circuit for 7.5 amps. this means that anything more than what the fuse is rated for will blow the fuse.

Let's also say that the horn and direction signals will draw 6 amps, so another 7.5 fuse is used or maybe just a 15 amp
for everything, the fuses amp rating will cover the load but if there is a short circuit, the current drawn will be a lot
greater than what any of the lights and horn would have drawn and that current will blow the fuse.If the rating of the
fuse is 40amps, than that means the wiring has to be able to conduct 40 amps. You can't have a 40 amp fuse protect a
circuit wired with 14 gage wire which is good for 15 amps or even a circuit wired with 12 gage wire, good for 20 amps.
JUST because the wire does not flame up, it burned the insulation off the wire.

So what does this mean Neels? it means you have to play the part of an electrical detective, unraveling the harness to
separate the wires and see where the trouble is. When the 1st fuse blew, was the ignition sw. on or off? If it was off,
then the trouble is between the battery and the ignition switch. For good wiring practice, the fuse should be as close to
the battery as possible. If the fuse blew with ignition sw. ON, then you have to physically check each circuit after the
ignition switch. A lot of bikes use the bucket ( inside headlight enclosure ) to make connections. So on r. hand grip you
will have at least 3 switches, engine run/kill, starter sw. and R hand direction. L hand grip will have headlight dimmer,
horn and L. hand dir. signal. Chances are the rear liting could have shorted, either the tail/brake-lite or dir. sigs.
Wires up inside rear fender, insulation over time got worn away.

Go to other side of ignition sw to find where wires branch off to different loads/ circuits. With out a wiring diagram for this bike,
it won't be easy to figure out, but it is still possible to fix, just going to take more time. Go to Napa auto or other auto parts store
and buy some crimp connectors and fuses, they are possibly the square colored job with flat wire terminals and hook-up wire.
Do you have a multi-meter? volts an ohms anyways?, if not get a socket for an 1157 bulb. hook the two black wires together and
crimp to a longer wire, put a gator clip at the end and make similar wire for base of socket or the metal part of bulb to which the
glass bulb goes into. Now you have a tester and putting in circuit across the fuse holder, will lite and current through that circuit =
to what bulb draws. looks like you R gonna need help with this, so if u want give me a holler, 727-204- 2767, I'd say we have a
good chance of getting that bike of yours that looks like the pic, running.
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Hello Neels,

Try to find a wire that comes out from left side of engine as the stator will be there, Most likely just two wires in a black plastic
casing with a plug or connector, that mates up to a metal box, this will be your R/R rectifier regulator. It changes the alternating
current from the stator into Direct current. Possibly it just went 'POOOF' This R/R will most likely have fins on it to shed heat.

As said in my 1st posting, feel free to call me, I feel that we can fix this issue. No $$ is required at all, some guys are machinists,
I'm into the electrical and frankly trouble shooting is a hobby, heck if I can help you get a cool bike going, I'll be pretty glad about
it, and I'd be helping you learn more about bikes. I have worked on major appliances, my trucks, bikes and yes locomotives.
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