More electrical testing....

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CMSMJ1
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Re: More electrical testing....

Post by CMSMJ1 »

My GSXR genny was banging out 65+ at 5k revs..it does give the reg/rec a hard time!

If I had the brains and motivation then I'd love a mosfet one. Or, more random, can you fit a pair of std ones?
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magg
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Re: More electrical testing....

Post by magg »

Adding a second rect/reg will not work because they will not load share. The voltage is not the problem, the maximum output current from the alternator is. Why do you say your rect/reg is having a hard time? A MOSFET rect/reg matched to the output of the alternator will certainly run cooler.
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CMSMJ1
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Re: More electrical testing....

Post by CMSMJ1 »

on the drift - I have a large Yam reg rec - it is bloody hot when running..hot enough to burn you.

I assumed the GSXR genny is dumping so much waste into it as usually it would be powering an injection system and always on lights etc...

I'll scope out some Mosfet - the whole charging circuit needs rewiring when I fit the genny to my current engine.
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magg
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Re: More electrical testing....

Post by magg »

Is the rect/reg mounted in the usual nc30 location, have you used heat transfer paste between the chassis mounting plate/surface and the rect/reg, is the mounting plate/surface flat. The chassis metalwork around the rect/reg should be at a similar temperature to the rect/reg if the heat is being transferred efficiently.

Electronics can run hot, engineering to run cold costs and is not always necessary. However, efficiency of the heat removal mechanism can sometimes be badly engineered or can deteriorate over time. With motorcycle rect/regs IMHO it is poor engineering.
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bikemonkey
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Re: More electrical testing....

Post by bikemonkey »

Right so after sleeping on it and re-reading everything, I agree my reg/rec is working fine. For some reason I got it all the wrong way round in my head.

What I still don't understand though is why the battery is barely charging/not charging at all.

I shall re-check the stator readings after I've fettled the carbs to get them right this morning, and if things are still a-miss then I'll untape my wiring and inspect. I would be re-doing it anyway but it'd be good to find the cause/rule one possibility out.

On the re-wiring front, would it be a good idea to replace the reg/rec plug with a pattern one from wemoto, as the original's spade connectors are a bit corroded?
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vfrman
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Re: More electrical testing....

Post by vfrman »

If your plug is dodgy, replace it. The lower the resistence in the wiring/connectors, the better.

How old is your battery? They do expire....perhaps it is time for a new one.
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bikemonkey
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Re: More electrical testing....

Post by bikemonkey »

Battery was brand new a year ago, lithium ion one too.

Think I'm going to replace the plug and re-do all of the reg/rec wiring and most of the alternator too, just to make sure.
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Re: More electrical testing....

Post by vfrman »

Good luck.
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bikemonkey
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Re: More electrical testing....

Post by bikemonkey »

Thanks.

Soldering iron has just come, and I've ordered a new reg/rec plug with connectors.

Just tried to re-do the alternator readings and it seems my multimeter isn't playing ball, so I'll try again later after I've adjusted the carbs, again....
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speedy231278
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Re: More electrical testing....

Post by speedy231278 »

I'd fix the electrics first. No point in having a sweet running lump if the battery goes flat in five miles!
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