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I have an 1991 CBR 600 F2 (beleive its a California version, I'm in Norway) thats gone approx 30000km with what I believe is original stator and rectifier. The bike died on me while riding on the road, the battery was very hot when I changed it for a new one on the side of the road. A couple of batteries later I decided to measure some electric components. The bike was over charging with a voltage of around 17V at 5000rpm, I changed for a new rectifier and the bike now is between 11-12V at 5000rpm. I have little experience when it comes to electricity. I can add that one of the wires that come from the stator looks a little burnt/melted in the plug that goes into the rectifier.
If I remember correctly the stator dynamic test gave around 25volts. Do you have any suggestions to what I should test and as to what the issues might be? I have not had time to visually inspect the stator yet, I have yet to order a new gasket for this. The bike may sound to run a little rougher now than before the charging issue.
Welcome to the forum.
The R/R overcharging looks like it damaged your stator or as you have stated at least one of the wires.
At 5k revs the voltage should be about 14.3v or thereabouts so you definitely have a problem.
You need to get the burnt wire fixed as that is a big problem and will be causing increased resistance and the risk of fire due to the heat.
Then re-measure the voltage at 5k if it is still very low then it looks like the stator is toast and will need replacing.
Tests on the stator:
Resistance between the yellow wires at the terminal block 0.1 to 1 ohm
Continuity between yellow wires and earth - No Continuity
Hope this helps
Welcome to the forum.
The R/R overcharging looks like it damaged your stator or as you have stated at least one of the wires.
At 5k revs the voltage should be about 14.3v or thereabouts so you definitely have a problem.
You need to get the burnt wire fixed as that is a big problem and will be causing increased resistance and the risk of fire due to the heat.
Then re-measure the voltage at 5k if it is still very low then it looks like the stator is toast and will need replacing.
Tests on the stator:
Resistance between the yellow wires at the terminal block 0.1 to 1 ohm
Continuity between yellow wires and earth - No Continuity
Hope this helps
Hello and thank you for the welcome ,
I've have since had time to do some more testing. Stator:
Values were measured through the connector block pictured below.
0.3 ohm on all three yellow wires
Continuity between yellow wires
No continuity to earth through yellow.
At least 50 V AC at ~3000/4000rpm (sounds like its gonna take off going to 5000rpm hehe)
From what the Haynes manual says the stator seems to be OK, based on the measured values?
Green wire in connector block has continuity to frame ground and battery negative. I know the ground goes through the starter relay before the battery, could there be an issue there?
I have been able to borrow two other Honda R/Rs from a guy at work, I will try and clean the connectors in the block and test these R/Rs before opening up for the Stator.
Original R/R - Voltage is too high at anything other than idle.
New China R/R - Voltage is too low at any point.
Picture of connector that goes to R/R
1991 Honda CBR 600 F2
Last edited by Chris91F2; Apr 24, 2025 at 02:33 AM.
Which wire is it? Then I can trace it on the wiring diagram and say how it should behave.
It's one of the yellow wires at the connector block to the R/R. It's very limited with the parts I can get in Norway online, most have to come from the UK or eBay etc.
I borrowed an R/R from someone at work, 14V charging at idle and dropping as rpm increased.
Then I cleaned the connectors as best I could with some sandpaper pressed into the connectors (unable to remove them from the block) and seemed to charge good at 14V at idle and 5000rpm. Same results on around 4-5 tries.
I will try to test it again today to verify.
UPDATE.
The charging situations seems to have been resolved with a second new RR.
NEW ISSUE
I have now changed oil (putoline sport 4r 10w-40) and had the pleasure of riding two short trips before the bike would not start...
1.trip OK
2.trip ( to and from work) - bike started right up with Choke, rpm increased. Choke off, got 10meters before bike died, started right up and no problems.
3.trip - bike started right up with Choke...rpm did not increase. Died approx same place as on trip 2, bike does not start again (it does turns over).
Engine turns over but gives no indication of trying to start. Cranking speed appears to be the same.
Removed 1 spark plug that was easy to get to, plug seems to be "healthy", gap seems ok and it gives spark. No indication of fuel or oil fouling.
Drained fuel bowl of leftmost carb, does not seem to refill the bowl when cranking.
Noticed crack in vaacum? hose that goes from leftside of engineblock to petcock. Tried to hold over the crack when cranking, no change.
Any suggestions are veryvery much welcome. Plug nr.1
With a leaking vacuum pipe you’ll have no petrol feeding to the carbs and it takes a lot of cranking to refill the bowls before it will start.
Firstly, replace the hose.
Then suck on the pipe to create a vacuum (or find a better alternative, it doesn’t need much pressure drop but you need to hold it for a couple of minutes) to allow the bowls to fill without killing the battery.