help a new vfr owner

hello all I am Jesse I just bought a 1994 vfr 750 and when I bought it it ran nice (with a new battery i supplied) owner said all it needed was a battery, put new bat in and ran nice so i bought it , after riding a few min the battery died did some research here and figured the r/r was bad bought a new one and when i put it in the 30amp fuze blows instantly, if i put the old r/r back in it starts and runs fine till the battery drains out
help any suggestions?

 

Do you have a multimeter / voltmeter to do some testing? Battery should be fully charged prior to starting tests.

Rollin

 

yes I do,,,,,,,,,,,,,,,,,,,,,,,

 

you are in duluth ga?

 

Hello
A common problem on specially this vfr is the rectifier, it is the problem in 90% battery deaths

Regards from Denmark

 

Well it's technically Johns Creek now but it used to be Duluth.

Rollin

 

bad r/r's on VFRs are legion, but blowing the main fuse when installing a new just should not happen under normal conditions.

Abnormal possiblities:
The new r/r is not the correct one for the vfr.
The old r/r is not stock and the connector was rewired for it.

OEM and replacement r/rs meant to use the existing wiring connections, when connected, will have three yellow wires from the stator to the three identically sized spades in the r/r. The two wider spades are for the red wire + output to the battery and the green - frame ground wire.
When mounted to the frame, a stock r/r/connector combination will have the green and red wires closest to the frame (the stator wires being outboard) with the green/ground wire above the red one.

When disconnected from the r/r, if the red and green wires make contact, you will smoke the main fuse. This shouldn't happen with the stock connector, but I'm guessing that you don't have that. (if there was a short in the connector, you'd blow the fuse with either r/r)

Greg

 

how good are you with the vfr? I was going to pay the shop 70.00 dollars to find the proublim but would rather pay you to come out and see if we can get the issue resolved??

 

MapMaster I did notice the wiring harness was not there when i bought the bike, and yes the red and green are closest to the bike frame, (with rad on top and green on the lower connector with the 3 yellows above) I do have the service manual and did connect it up correctly, still stumped

 

Further input.
You said the battery died after just a few minutes. Define few.
Running with no charging at all from the r/r should get you at least a half hour to an hour on a fully charged battery.
Was it charged up, or had you just dumped the acid in it and installed it?

If it was fully charged and it did die that quick (< five minutes), you have a short somewhere in the system. Get a wiring diagram and start searching, I'd check out the starting circuits first.

Are you sure the r/r is bad?
How many miles on the bike?
If there is no short and it's not charging properly (roughly 14.0-14.5 vdc at the battery when running at about 5,000 rpm)
Diconnect the r/r and check the AC voltage across each pairing of the three stator outputs (with a charged battery, starting without the r/r connected is no problem) you should see close the same voltage across each pairing for a given rpm. The voltages will be higher at higher rpms. About 15-20 VAC at idle, going up to 50+ as the rpms climb. Actual values aren't what's important here, it's that all pairings should be very close to the same. If they are and you get no charge, the r/r is kaput. If they aren't - you need a new stator (Ricks motorsports electrics has them much cheaper than even well discounted OEM units will cost).

Finally, if all the wiring is stock, you can find many diverse recommendations for improving/upgrading things in this area. What I would suggest is running a direct 12 gauge stranded wire from the r/r ground to the negative battery terminal and run a second from where the r/r was grounded to the frame to the terminal as well (where the r/r is grounded is another lug grounding other circuits to the frame. The existing battery ground runs from the frame up on the left side of the engine. EE's that I know and trust feel that the stock grounding scheme is the weakest point of the whole system.

Finally, for a bike that old, anytime you replace components, be sure to clean or replace the connectors involved. Use Noalox (available from Lowes, HomeDepot and I think Radio Shack) on the connectors to minimize corrosion and coat the outside of them generously with dielectric grease.

Always stranded wire, crimp connectors (no solder), and a good crimp tool, not just pliers.

Greg

 

Where are you located?

 

You said the battery died after just a few minutes. Define few.

it will run for a 1/2 to full hour

Was it charged up, or had you just dumped the acid in it and installed it?
when I bought the battery it was just filled with acid and put into bike I have since then did trickle charging a few times


Are you sure the r/r is bad?
How many miles on the bike?

30,000
If there is no short and it's not charging properly (roughly 14.0-14.5 vdc at the battery when running at about 5,000 rpm)
Diconnect the r/r and check the AC voltage across each pairing of the three stator outputs (with a charged battery, starting without the r/r connected is no problem) you should see close the same voltage across each pairing for a given rpm. The voltages will be higher at higher rpms. About 15-20 VAC at idle, going up to 50+ as the rpms climb. Actual values aren't what's important here, it's that all pairings should be very close to the same. If they are and you get no charge, the r/r is kaput. If they aren't - you need a new stator (Ricks motorsports electrics has them much cheaper than even well discounted OEM units will cost).

Finally, if all the wiring is stock, you can find many diverse recommendations for improving/upgrading things in this area. What I would suggest is running a direct 12 gauge stranded wire from the r/r ground to the negative battery terminal and run a second from where the r/r was grounded to the frame to the terminal as well (where the r/r is grounded is another lug grounding other circuits to the frame the existing battery ground runs from the frame up on the left side of the engine. EE's that I know and trust feel that the stocking grounding scheme is the weakest point of the whole system.

Finally, for a bike that old, anytime you replace components, be sure to clean or replace the connectors involved. Use Noalox (available from Lowes, HomeDepot and I think Radio Shack) on the connectors to minimize corrosion and coat the outside of them generously with dielectric grease.

Always stranded wire, crimp connectors (no solder), and a good crimp tool, not just pliers.

Greg

 

Your red and green wires have been swapped to work with an non standard (from the VFR stand point) rr. That's why the fuse blew.

 

Marietta Georgia that post was for Rollin_Again
he is in georgia
I will try the things you recommended tomorrow and go from there thanks Greg

 

ok but the new r/r I bought has the wiring diagram and it shows the red on top if looking at a mounted r/r and green on bottom ?????

 

Most welcome.
Check the stator before swapping rr wires back around. And if you do have to rewire, disconnect the battery first - or have a supply of 30 amp fuses on hand (damhik :frown

edit:
Your stator should be okay (but check it first anyway), the original one on my 96 lasted 160,000 miles

 

just bought a box of 30 amp how do i check the stator ? do i test voltage at the contact point behind the middle flaring?

 

I described how to do that in my second post. Feel free to ask for clarification is something is not clear.

 

I don't mind lending a hand and I just happen to have an extra R/R. I was coincidentaly planning on going to Marietta this week to check out some used bikes at WOW (World on Wheels - Cobb Pkwy) so send me a PM with your schedule and we'll try to set something up.

Rollin

 

Jesse,
I missed this response during the evening exchange.
My assumption was that you bought a honda rr, or at least one meant to be a direct replacement, and that the old rr was one with swapped outputs. Your reply makes me think the reverse may be the case.

The following questions are meant to help you figure out what's going on, so I don't need individual answers to them as such. Hope it helps.

In another response you said the wiring harness was not there, what exactly do you mean by that? Are all of the rr connectors bundled into a single plastic casing, or not?
What rr did you buy? (the red on top is not the correct orientation for the VFR connector) - was there a note that the standard VFR connector would not work in this application - perhaps you should contact the rr vendor.
Do you know what the old rr is? (OEM, aftermarket, replacement originally meant for another bike, whatever).
What was the orientation of the red/green rr connections for the old rr?
You said that the fuse blew when connecting the new rr (before a start attempt right?) If the connectors are all separate, are they shrink wrapped/taped all the way to the end? If not it would be far too easy for the red/green connectors to touch while unconnected and that will blow the main fuse immediately since it's a direct + to - short of the battery. The same would happen if the red just touches the frame. Again, best to disconnect the battery while fussing with the rr connectors.