main (?) fuse keeps popping...

[Rial]

i got my bikes electrical put back together to see if i could start it today (its in the middle of a re-/street fighter build). i started the bike up and it ran for about thirty seconds, then it died. i couldnt start it back up so i started looking at things and found that the 30 amp fuse that goes on the left side of the seat had blown, so i replaced it, started it up and again, the fuse blew.
the ecu(?) (big black unit with heat sinks) looks like it was jerry rigged so im wondering if i i have a wire crossed there. it has 4 wires going into it. 3 white and 1 red, and the ecu itself has a wire coming off that is a ground.however the 4 wires that come from the harness hook up into 4 blue wires used as an extension... is there a way to check to see if the 4 wires and the ground are connected correctly? i made sure all the grounds are well grounded. this was the only thing i could come up with...
thanks for any future help!!!!

ill try to get some pics if it comes to that...

[cad600]

That is the voltage rectifier (VR). It could very well be the source of your problems. Need a picture though. You described it as having a heat sink but only 4 wires running to it. The older ones used only 4 wires but did not have a heat sink. The newer ones uses 5 wires and the heat sink is an integrated part of the unit. If you do have the newer one and only 4 wires going to it, then that is the main cause of the fuse blowing. However, this can also cause other problems that you may encounter after this one is fixed. basically, bad VR's tend to cause other things to go wrong.

[reelrazor]

Unplug the red wire from the VR, replace the fuse and start the bike. See if it blows the fuse..I suspect it won't.

Put a meter between the unplugged red wire and the chassis/battery negative....see what it is reading at idle...what's it read for voltage? Rev it....does it climb over 14.5Vdc? (I suspect it WILL).

If voltage is high (over 14.5 Vdc) with revs, your VR is bad-replace it.

[Rial]

thanks. i will do both of these things tomorrow. and let you know. im pretty sure the VR is a newer one.

[shredex]

check for a bad ground as well.
mine did the same thing when i had a split wire in my ignition that was grounding out on my coolant cap.

[yamaha_george]

thanks. i will do both of these things tomorrow. and let you know. im pretty sure the VR is a newer one.

Rial,
if it is a new one take a look at:-

http://www.saltmine.org.uk/fzr/vr.html

and you can see how mine is wired when I went from old to new.

[Rial]

i just uploaded 3 pics in my gallery of the VR and the wires. there are 5 prongs on the VR and 4 wires coming from the harness. how do they hook up?

[tkclow]

Here is the link from the wiki on the swap and wiring

http://fzronline.com/wiki/doku.php?id=r ... conversion

Hope this helps

[reelrazor]

thanks. i will do both of these things tomorrow. and let you know. im pretty sure the VR is a newer one.

Rial,
if it is a new one take a look at:-

http://www.saltmine.org.uk/fzr/vr.html

and you can see how mine is wired when I went from old to new.

Dyed in the wool two-strokie ya are, Geo.....I see the pic with a set of sparkies next to the tool kit!

[Rial]

thank you soooo much. i got it hooked up right and fired it up today. runs like a champ!!!!! thank you thank you