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Starting issue 99 Dommie - electrics?

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Refitted battery after charging. When turn ignition key on amp meter normal deflects slightly to left but today nothing and no sign of life on kicking. Turned light switch to on position to check lights but no lights. Pressed horn to check and proved is working (ignition key in any position)  leaving light switch in on position (pilot or main beam) these lights came on immediately the horn is pressed with meter reading on to left or far left of amp meter. Kicked over a few times and bike started. Went to restart no deflection no start and no lights. Pressed horn and this cycle starts again. If when ignition is on press rear brake pedal that light comes on but nothing happens to lights when in pilot or beam position on switch (i.e. stay off).. Bike revs OK and amp meter registers charging when I can start it but stops when revs drop to normal tick over but suspect ignition has been cut out by whatever problem is although obviously no time to warm engine up. The horn switch is making a good contact with the handlebars and the combined dip switch seems to be working. With key in ignition position no lights majority of times (pilot or main beam) on simply putting ignition key to on although rear brake light always works and lights will come on occasionally although not triggered by brake light. The obvious is the horn and dip switch (Wipac from 25 years ago when restored) but as horn hardly ever used and never use lights when out I wonder what can go wrong with it and why it kills ignition circuit? There is no kill switch. Any ideas where to start? Any help appreciated since as you probably appreciate a novice in terms of understanding electrics (and all other areas!). Hugh   

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To start with I would run a couple of extra earth wires.  One from the headlamp shell  back to the frame near the battery. And an earth from the engine  to the same point.

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The head lamp shell does NOT need an earth. The connector at the rear of the headlamp bulb does. Along with the side light (common earth point) but the headlamp-shell does NOT, ignore it. Earth to rear of headlamp connector run back to head steady and on to a bolt in the ares of the tool tray/battery box/rectifier. And bring another earth from the rear light to the same place, AND a single wire to battery Earth/positive. Single wire on each battery terminal! If you have several wires on each then one will be forgotten or put n the wrong terminal next time-result is confusion and expensive smoke.

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IF after charging the battery and refitting, then the first area of 'dodgy' is the connectors from the battery to the bike or even the battery it self. Easy sort out, get a test lamps on two wires-clips or probes. When bike is dead, place across battery if it doesn't light then battery has died inside. If it does light up then follow one lead at a time until you find or lose the electricity. Simple.

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... a 5/16 bolt in a convenient place near the battery earth and run individual earth wires to that - each with its own ring terminal so they're "stacked". No stereo fitted so no chance of earth loops!

Unlike Al and others I have a fuse in the earth lead (negative on the ES2) to the earth point.

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If you have a distributor , it relies on  bolted  engine  parts  and painted plates to carry the current these can have 60 years of rust, grease  and corrosion or maybe  a nice thick powder coat. Give me a wire and  connections that can be cleaned and  protected with a bit of vaseline. The orriginal layout on my 99  had the lighting earths connected to the headlamp shell with the speedo bulb earthing on the shell only and all earth current going through the head bearings or control cables. ERGO   one decent earth to the shell worked for me and provided a path for the speedo bulb which will otherwise still have to use head bearings. 

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Thank you all. I will let you know how I get on although I have a bad back at moment which is slowing everything down (all sent  o try us). The dip switch has now given up and not even the horn press is lighting anything up now. Hugh

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In your case and a lot of cases the head shell is used as a convenient 'earth point' fine.

But the head-shell it self does NOT need an earth, it is just often a convenient earthing point. I have always taken the headlamp connector as the earth from the rest of the bike and used it to loop to side light, and speedo lamps if you need them.

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I converted to 12v  25 years ago   and so did away with the  PRS8 switching arrangement (but kept the switch)  ,this meant that there were redundant  substantial  (orriginal) cables   in the loom up to the headlight shell.,(although the wrong colour)  ,a bit of red sleeve  both ends gave me a  dedicated earth wire through the bike  with no extra cabling  or the  bother of threading it through  the loom.  Thrifty and lazy !.

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You said you removed the battery, then charged it and then refitted it. Did the bike run normally before that?

If you didn't do anything else, I'd suggest bad contact in battery connections. When you push horn button the big load breaks up the corrosion and everything starts to be normal for a while. So I think that cleaning battery connections will solve the problem. I usually put star washers on bolted electrical connections as they dig into the metal giving better contact..

If the bike has not been ridden for a long time, some other connection could be the culprit.

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As you have a distributor  you may wish to go for an orriginal look ?, in which case a PSR8 switch will work. fine . But its not always  really needed  and is a bit complex.  If you are not going for a modern rec/regulator or zener  then the PSR8 switching  is usefull to avoid  overcharging the battery  even if the control is a bit basic. At least it gives you an ignition and lighting switch.

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Thanks Robert. I want to stay with an original look - but go 12v with electronic ignition for ease of starting and reduced maintenance. I will put PRS8 on my shopping list!

Steve

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The PSR8 switch  does turn up  for sale, Orriginal  ones can have a damaged thread which makes them hard to secure and  the 2 part  knob securring screw  is  a bit  delicate . They are also a bit vulnerable to water ingress if the rubber key seal is poor or missing . Proper bezels are elusive too.  They can be stripped and cleaned with care but  its a fiddly job.  Pattern ones are easily found but  quality may  be  suspect ?. Mine has a couple of wire  screw terminals that have rusted solid so I may have to do some delicate surgery.

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Amazing things. I gave up on them many, many years ago. Blow originality, I want reliability, not something that is an electrical fault (or two or three) just waiting to happen. 

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My PRS8 is just fitted for show, not a single wire going to it.  My lighting comes from my ignition switch installed just below the seat.

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Strangely my PRS8  has always worked fine , the knob got a little loose but a rubber shim  cured that . I would like to fit a new HL shell  but the seized terminals have put me off ,I could always cut the wires and  solder/sleeve them back. I could also drill out the screws and tap the threads clear ,for new screws  , wonder what the threads would be  ,  B A ??  

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There is details on my web site (AOServices.co.uk) of how to strip and rebuild this switch. I also have some spare parts. Yes they are 2BA and 4BA on the original but of course likely to be Metric on the new far eastern copies. Robert's words above are very true.

 


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