Jump to content

86 VFR700 solenoid harness melted


WingNut

Recommended Posts

Hey guys, I'm working on a buddy's VFR700. It blew the main fuse at the starter solenoid a couple of times, once while trying to start it, and once when only the key was turned on. It seems that the electrical system is weak on some of these if i'm not mistaken. But now it falls on me to figure out if the blown fuse is a symptom of a deeper issue that caused the solenoid plug to melt, or if the fuse is blowing DUE to the melted plug. I'm leaning toward the latter, but I'm calling on you guys and your expertise, since I don't have much experience with these.

 

I've read about the VFRness kit that WireMyBike sells (it appears he might be a member on here by the name of Tightwad?) Since the kit seems to replace this plug, I'd love some input from you guys on whether or not you think this is the issue and if it's a good fix for it before I just start throwing parts at it.

 

Oh, I also tested the diodes in the R/R, and as best I can tell they're still good.

 

Thanks!

Link to comment
Share on other sites

  • Member Contributer

Make sure the 4P wiring plug to the Starter Relay is Correctly orientated! Making sure that the Green/Red and the Yellow/Red wire are going to the Starter Relay Coil.

The Red wire (or if you have 4 wires, then the Red/White as well) must be going to the Main Fuse.

If the plug has been incorrectly fitted then you may have also shorted or blown the Clutch Diode.

 

Apart from that you'll have to start unplugging devices to isolate the short starting with the R/R, check Ignition switch, check for burnt connections, and then removing fuses.

 

Good Luck.

 

You can also download the Service Manual from this forum. Downloads Section

Link to comment
Share on other sites

a very common problem on that bike !  u can buy a replacement plug with wires attached on amazon or ebay.  it is, however, chinese and may therefore have a short service life.

 

https://www.amazon.com/FLYPIG-Starter-Solenoid-Connector-CBR1100XX/dp/B06XC7KY6S/ref=sr_1_2?crid=34H233JETF94C&dchild=1&keywords=solenoid+plug+connector&qid=1600040247&sprefix=solenoid+plug%2Caps%2C252&sr=8-2

 

corrosion on the connections causes heat build up and melting wires.

 

620878890_sept132020009.thumb.JPG.cd0b17edd0ff02781763243356b66319.JPG

 

 

 

 

Link to comment
Share on other sites

Yep all too common. Pull the body panels and gas tank etc off, clean and check every connection. Pull every single connector apart, clean the terminals, pack with dielectric grease to keep corrosion at bay, and put back together. Your hand controls might feel crunchy and need to be taken apart and refurbished as well. Pull fuses, check, and clean those little terminals and put it back together. Pull bulbs, make sure they look good, clean the sockets, toss em back in.

 

You're prolly going to have a melted connector with the 3 yellow wires coming off of the stator. You can get a cheaper reg/rec kit to hard wire to that(as in snip that connector and direct solder the wires together), then hook the charge wires directly to ground/the battery and skip that little main fuse. Roadstercycle has nice kits if you want USA nice stuff, or feel free to read about why he does it this way and source your own dubious kit on ebay or something http://www.roadstercycle.com/Easy Mosfet Install.htm

 

Toss the battery on a trickle charger and get it nice and topped off, motorcycle charge systems aren't meant to charge a flat battery, that can cause extra heat in the system and end up melting things.

 

If you spend a weekend doing all of this work you won't have to fuss with the electrical system ever again in your lifetime, short of battery swaps.

 

The fastest/emergency way to do it is replace that connector, pull all fuses, and replace one by one until it start blowing. It could be something as silly as a light bulb hard shorted out and the fuse for that circuit being over sized.  I would vote do the full check and inspect though, these bikes are antiques at this point and it being a Florida bike I assume it has lots of corrosion in those connectors, which are bad even in the rust free central Texas environment mine grew up in. Those old school spade style non sealed connectors just suck honestly.

Link to comment
Share on other sites

  • 3 weeks later...

Alright, problem solved. Er...discovered.

 

I replaced the solenoid connector with the kit from CycleTerminal (http://www.cycleterminal.com/solenoid-connectors.html) which worked great. But as soon as I connected the battery, POP! The main fuse blew again, even without the key turned on. It was just under the normal 12 volts from the battery.

 

So I disconnected the battery again, and disconnected every plug that I could access (basically everything but the headlight and gauges). I put a new main fuse in, and connected the battery again, and it was good.

 

So then I one by one started connecting the wires again. My final connection was (intentionally) the regulator/rectifier. As soon as I connected it, the main fuse blew. 

 

It was surprising to me because the R/R connectors are like brand new. They're not showing any sign of being heated or overloaded. But it appears that there's an internal short in it.

 

So my question is, is the link ATX posted above (http://www.roadstercycle.com/Easy Mosfet Install.htm) and (http://www.roadstercycle.com/index.htm) the way most of you guys do it?

Link to comment
Share on other sites

Was the stator connected when you plugged the r/r in? Disconnected the stator, meter those out and see if you get similar resistance between all 3 wires, but more importantly make sure none of those have path to ground.

 

Again you don't need to go for the expensive kit if you can't afford it, ebay search for FH020AA or whichever mosfet regrec you want and you'll find workable chinese versions, and you can swap those out to genuine later if the cheapie fails.

Link to comment
Share on other sites

  • Member Contributer
5 hours ago, squirrelman said:

i believe the fuse might blow if the two wires from the start circuit are incorrectly placed, left-to-right.

 

No Sir. Swapping places of the Yellow/Red and the Green/Red wires (Starter Relay Coil) should have no effect. Most relay coils are not polarity sensitive including the Starter Relay Coil, there would also be no issues with the Neutral and Clutch diodes. So shouldn't have any effect on the Main Fuse. (according to the Starting Circuit diagram I have!).

 

If the Starter Relay connector can be incorrectly fitted 180deg out, then that's a very different story!

Link to comment
Share on other sites

  • Member Contributer
On 10/7/2020 at 10:13 AM, squirrelman said:

"might" was my out cuz i was far from sure about my statement.  thanks, grum. i've never read one of your posts that wasn't spot-on.

Thanks mate.

Wasn't trying to be a smart ar@e, just trying to keep the info accurate where possible, don't worry, I've certainly made a stuff up or two. I know precious little about the stuff you are talented with.

Cheers.:beer: 

Link to comment
Share on other sites

  • Member Contributer
On 10/1/2020 at 6:52 PM, WingNut said:

I replaced the solenoid connector with the kit from CycleTerminal (http://www.cycleterminal.com/solenoid-connectors.html) which worked great. But as soon as I connected the battery, POP! The main fuse blew again, even without the key turned on. It was just under the normal 12 volts from the battery.

Uh... how can it work great when you don't even have battery connected?

 

Take photo of how you have each and every single wire on solenoid connector inserted into connector housing.

Then post it here.

Link to comment
Share on other sites

  • 2 weeks later...
On 10/6/2020 at 10:37 PM, DannoXYZ said:

Uh... how can it work great when you don't even have battery connected?

 

Take photo of how you have each and every single wire on solenoid connector inserted into connector housing.

Then post it here.

It can work great in that everything went together and fit without a problem 😛 It's not that hard to connect 5 wires the same way it came apart.

 

On 10/1/2020 at 9:02 PM, Smack said:

I'm following this as I most likely will need to do the same on my '86 750 one day...

Please follow-up on the problem.

Brian

The Roadstercycle.com upgraded Mosfet R/R was the ticket. We hooked it up a couple of days ago and we had no issues. The R/R itself is a little bigger than the original one, and it's not threaded, so you need to get creative in how you mount it to the bike.

 

Jack, at Roadstercycle, is super helpful too. He even gives his phone number on the site so you can call with any installation questions. I highly recommend it.

 

Thanks for the help guys, looks like this one's a wrap.

 

Link to comment
Share on other sites

  • 4 months later...
  • Member Contributer

Early warning?    That is WELL f#cked already.....  :laugh:

Link to comment
Share on other sites

  • Member Contributer
22 hours ago, squirrelman said:

early warning of coming failure looks like this

 

 

june_1_2019_014.JPG.62cc9a2adb1555fa1c5e0f615599b2b5.JPG

Interesting photo Squirrelman, what year bike is it from? Surprised to see that there are two heavy gauge Red/White wires to only one of the spade connectors. Did this model only have the one 30amp main fuse, the one housed in the Starter Relay?

Link to comment
Share on other sites

Archived

This topic is now archived and is closed to further replies.

×
×
  • Create New...

Important Information

By using this site, you agree to our Privacy Policy.