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I have been having a few problems with my bike lately, the first one being it wouldn?t start found a wire to the neutral relay switch lose and my cut-out switch had a broken wire. Went for a spin and everything was fine, next morning went to start the bike, I let it warm up for 5 mins but it wouldn?t go over 6000, it would gurgle and then cut out. Checked the petrol and its getting into the carb, the carb had a clean out a few weeks ago, spark plug ok. I think it might be another electrical fault as its not even running now, might start for a second then die like it did before and for some reason it is sparking, then it isn?t sparking. I took the wiring loom out and check it all and cleaned all connections, and everything is ok. Now what is the most likely cause of this in the electrical system?
This bike is really doing my nut in
 

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Did you check for a spark outside of the engine? Attach your plug to the HT lead, put the bottom end on your engine casing, and try to start the bike. You won't start it, but you'll see a spark if there is one.

Oh, and remember to hold it by the insulated bit of the HT lead so you don't electrocute yourself!
 

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change the spark plug as a matter of course, they are so fickle.failing that, to to dj unreal
 

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So sometimes it sparks, and sometimes it doesn't?

That tells me it's one of 3 faults.

1) Dodgy HT lead.

2) Dodgy CDI.

3) General dodgy wiring.

You should eliminate 1 and 3 before worrying about 2.

I keep telling people to do this, so i'm going to post a link this time to a decent multimeter that everyone can afford (once I get round to googling for it).

When my link appears... Go buy one. Shouldn't be more than about 20 notes for a fairly reasonable one.

Set it to continuity, and touch the probes together to test that it will beep.

Then start poking around. The tester will beep if there is an electrical link with a low enough resistance for the tester to conclude that the link is there and fairly usable for general electrics to flow down.

Things like the HT lead would be easy to test - one probe on each end.

CDI, I haven't played with, so wouldn't know, best bet on that is to find a spare IF every single other thing works.

Oh, and double check the wiring on those cut-outs again. If the kill switch is shorting to earth then that'll kill your spark. If your ignition is switched off, or shorting to off, that'll kill it. If the side stand switch is shorting to earth (ie it's not registering that you're in neutral or that you're in first and your stand is up) then that'll kill the spark too.

Give all these bits a check with a multimeter (as I said, i'll find the link in a min) and report back


Thus ends your homework assignment for today. Homework due in 3 days.
 

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Had a similar one myself, the probes aren't too wonderful but other than that it's ok.

EDIT: Re-read it and found that it doesn't have a continuity buzzer. STAY AWAY FROM IT!!!

Had a quick look on maplin though, would recommend this one:

http://tinyurl.com/2gajrq

Uni-T are a great company for cheap and cheerful multimeters which work properly!

Don't know what probes this one comes with, but mine came with probes which have detachable crocodile clips on the end... SOOOOOOOOOOOOOOOOOOOOOO useful!!!

If it doesn't come with croc clip probes, you can always buy a set...
 

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Basically, it makes an audible sound when there's continuity. Much more useful than a digital readout which you can't tell is making a good connection.

My current one (also a UNI-T) beeps when the value is low enough, but shows a digital readout as well, so I know that it's just sh*tty wires and there /is/ a link just. Then I go about cleaning up connections until it works properly!

I know you might not have cash, but a multimeter is a thing you'll buy once and rely on for life.

In fact, when my new one arrives, I might be able to let my old one go for a stupidly cheap price. Not sure yet though.
 

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basically it checks for resistance.

so if you whack it on a decent wire, it will have little resistance and will complete the circuit and buzz.

if its f*cked and it split in the middle, you wont get anything.

you dont need a buzzer, you can just take the reading, but it does make life easier when you're working on ya lonesome.

that 5 quid effort will probably do you alright to be honest.

edit: ffs i'm obviously not typing fast enough lol.
 

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nah, if you wanna make good connections between cut wires buy:

A crimper

Some crimps

and bullet connectors.

solder is fine if you have excess wire, but this is not often the case with wires on a loom, i personally wouldnt use solder, its just not as effective as crimps and connectors.
 

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go to b and q, wicks, what ever

its not expencive stuff to be honest, you're probably looking at 5-10 quid for the lot depending on the quatitiy you buy.

soldering iron, probably 5-7 quid, maybe abit more. solder can be quite expencive, though.
 

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nah, if you wanna make good connections between cut wires buy:

A crimper

Some crimps

and bullet connectors.
solder is fine if you have excess wire, but this is not often the case with wires on a loom, i personally wouldnt use solder, its just not as effective as crimps and connectors.
Go see this link:

http://cgi.ebay.co.uk/Bullet-Connector-SET...3QQcmdZViewItem

Bought a set from them. They sell the crimpers for another 18 quid. That set is the best set i've seen...
 

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They the fully waterproof one though? Or are you talking about the ones with the attached plastic sheath?
 
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