Author Topic: How hot is too hot???  (Read 4323 times)

Offline laurie

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How hot is too hot???
« on: April 28, 2012, 03:59:23 PM »
The electrical gremlin saga continues.....I was fiddling around trying to figure out the Indicator/brake circuit problem with my bike when I noticed 3 things....
1, the fuse box gets quite warm...
2,the wiring out of the regulater/rectifier gets very warm..
3, the regultor/rectifier gets very hot,almost too hot to touch.
With regard to the rectifier,how hot are these things meant to get? I can see a rather expensive visit too a sparky some time soon.
Cheers
Laurie
 

Offline Whizz

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Re: How hot is too hot???
« Reply #1 on: April 28, 2012, 04:14:32 PM »
Laurie, in answer to your questions, any current flowing through a wire will cause heat...that's why the fuse blows if the current gets too high, the fuse wire melts. So it is reasonable to assume that a fuse box will get warm in use, the accumulation of heat from the various fuses in the box will do that for you. The amount of heat is directly proportional to the current being drawn, so the more farkles you have on-board and running, the higher the heat produced in the fuse box. The wiring from the regulator/rectifier is carrying the whole current load to the fuse box, so it too will get quite hot, this also holds true for the Regulator/Rectifier, which is working that much harder to produce the current that is being demanded, and it is not uncommon for rectifiers to get hot enough to burn the skin. However you need to remember that the heat is a by-product of the current being demanded by the electrical systems on the bike, so the more things you have running, the hotter your power generation system is going to run.
Hope this helps and I'm sorry if this sounds like I'm talking down to you, I'm really not.

Cheers
Whizz
 :13Candy
Cheers,
Paul
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Offline saaz

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Re: How hot is too hot???
« Reply #2 on: April 28, 2012, 04:35:01 PM »
Laurie, is yours a pre-96 model? The regulator/rectifier on those can get hot.  make sure all the connections are nice and clean and tight.  The fuse box can also get warm.  Any connections that are not really good will add to the heat generated.
John
(Ridden on and forever in our hearts)
1996 Honda ST1100P
2014 Triumph Trophy SE
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Offline laurie

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Re: How hot is too hot???
« Reply #3 on: April 28, 2012, 04:57:20 PM »
Saaz,Mine is a 95 model with the small output alternator. The rectifier was replaced about 4 years ago by the local bike shop,with a used on off a CB 900 I think. Its done the job up to now.

Whizz, no worries,I didnt feel like I was being talked down to. Ive got a reasonable understanding of electrics,and understand the basic principles. I know things will get hot,I just wasnt sure if what I was seeing was too hot..
BTW, there are no farkles on the bike besides an electronic cruise control.which draws bugger all current.
I am getting a bit cheesed off with the gremlins,to the point that the used ST1300 at the local Honda dealer is looking tempting...
Cheers
Laurie
 

Offline pault

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Re: How hot is too hot???
« Reply #4 on: April 28, 2012, 06:59:10 PM »
some time ago i blew a ignition fuse and the motor died, replaced the fuse idled OK went 30 m and it died again. tried again, idle ok give it some revs and the poxy in the back of the rectifier smoked before dying again. the rectifier had died sending too much current, remembering mine is a police model it is differant to yours, the poxy was cracked and leaking out.
replaced with a new one. it ran hot when replaced to the point I was afraid to put on the side cover, apparenty they run hot as normal, no trouble since.
for laurie's interest all this happened on that big blind up and down curve past the yashua turn, before dawn, biggest worry was getting run over by traffic either way.
ps i have nrma coverage, they took me home no worries.
 

Offline Whizz

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Re: How hot is too hot???
« Reply #5 on: April 28, 2012, 07:59:20 PM »
Laurie, one of the problems with electrics and the heat it generates is that, over a period of years, the heat will change the chemical make-up of the plastic that surrounds it. It tends to become brittle and crack, making good solid connections that much more difficult to make and maintain. This then becomes a vicious circle with the now crappy connections making things even hotter, accelerating the degeneration of the plastic stuff. This is why the older bikes (and everything else for that matter) start to suffer from 'gremlins', if you could afford to remove all the plastic which is really, by that stage, starting to turn to powder, and replace it with new stuff the problems would go away... but you can't. So looking at a newer ST1300 is not a bad idea because the plastic switch and connector bodies will be that much newer and less prone to cracking and generally stuffing up... and any way it's a 1300!!!

Cheers
Whizz
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Cheers,
Paul
:13Candy
In theory there is no difference between theory and practice; in practice there is!!
Red, 2004, ST 1300A
 

Offline alans1100

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Re: How hot is too hot???
« Reply #6 on: April 28, 2012, 09:06:49 PM »
Saaz,Mine is a 95 model with the small output alternator. The rectifier was replaced about 4 years ago by the local bike shop,with a used on off a CB 900 I think. Its done the job up to now.

Laurie

I'm surprised they didn't ask if you wanted to have the later 40amp alternator installed as some people go that way

1999 :bl11  2004 :13Candy

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Offline Greencan

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Re: How hot is too hot???
« Reply #7 on: April 30, 2012, 05:20:08 PM »
Quote
I am getting a bit cheesed off with the gremlins,to the point that the used ST1300 at the local Honda dealer is looking tempting...
Cheers



"Are you sure 'bout that???...Don't wanna phone a friend???"
 

Offline laurie

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Re: How hot is too hot???
« Reply #8 on: April 30, 2012, 07:51:45 PM »
Hmmm, thats the trouble with the interweb thingy...the incriminating evidence never goes away.
Still, the rider is a very handsome young cove.....
Cheers
Laurie