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new r/r

4K views 27 replies 9 participants last post by  w4nmh 
#1 ·
just replaced the rr today. put the bike back together. fired her up. idling 13 volts at 3500 rpm 14.5
rode for a mike dropped down to between 12.19 to 12.48

is this normal or is My bike possessed??
Ive had this bike for 14 weeks and only managed to put 280 miles. its reallyyyyyy teaching me patience
 
#2 ·
This is normal. As I said in another post. After the battery gets a full charge 100%, the r/r doesn't put out as much or shorts it to ground, so not to overcharge the battery.
 
#3 ·
thanks I think after all the problems im just a little gun shy. Im riding today
 
#8 ·
I stand corrected.

My eyes must have transposed the numbers but pappa is right 12.19 to 12.48v is quite low. When I tested my bikes the volts didn't drop below 13v. Sorry for giving wrong advise. I'm still learning as I go as well and get slapped once in a while. lol
 
#9 ·
we need to keep in mind that the readings should be taken at 3000 to 3500.rpms. At Idle they will generally read battery voltage.Also if your gauge is wired in around the headlight area instead of at the battery your readings will be a little lower.If you have an digital meter and are checking the output at the battery,at the proper rpm range that is a little low and might be cause for concern.
 
#11 ·
just replaced the rr today. put the bike back together. fired her up. idling 13 volts at 3500 rpm 14.5
rode for a mike dropped down to between 12.19 to 12.48

is this normal or is My bike possessed??
Ive had this bike for 14 weeks and only managed to put 280 miles. its reallyyyyyy teaching me patience


Possessed all of them are that is why we name them.
 
#12 ·
any ideas what would cause this problem other than loose ground
 
#13 ·
i bought a used rr but it has a 30 day warranty should I change it?
 
#14 ·
where is your voltmeter wired in at
 
#16 ·
should I replace this rr also. Ill check the ground connections today
 
#18 ·
checked all the grounds all seem okay. I must be missing something???
 
#20 ·
sorry I los t the lst view responses bike has about 12000 miles is a 95. is there a way to test the stator while on the bike or do we have to disassemble it????
BTW you guys are awesome Ive never known more helpful people so thanks again
 
#28 · (Edited)
Stator Cold Check

is there a way to test the stator while on the bike or do we have to disassemble it????
BTW you guys are awesome Ive never known more helpful people so thanks again
Checking without dis-assembly.

With a Resistance (Ohm Meter) check each of the three stator wires to Ground (with all stator wires unplugged). Each wire should show no or infinity resistance to the ground of the Battery/Frame.

If anyone of the Stators shows a ground, Stator is bad...

The initial output being better after you changed the R/R is probably because the Grounded Stator is more prevalent when the Engine is hottest.
When you changed the R/R was the Engine Cool?
 
#21 ·
voltmeter wired to batter directly
 
#23 ·
Update and need feedback on ideas

This is Journey's friend Blumeri posting this. I am an amateur EE (actually a physical chemist who has designed and built a good fraction of his experimental apparatus including electronics) but who is admittedly better with DC circuits than AC.

Anyway, I tested the voltage output of the alternator on each of the three output wires disconnected from the rectifier. I get 30-40 VAC vs ground on two or them and virtually nothing on the third. The third also measures close to zero resistance from ground when not running. I am now convinced that we have lost one of the phases. (I assume this circuit is a three phase power system). What I do not understand is why when we first installed the new rectifier we got as 14+ VDC out of the rectifier and then it dropped back to just above 12. I am guessing that the short to ground is intermittent, but frequent enough to be a problem.

I know that the correct way to fix this is a new stator. The problem is that Journey does not have the cash to buy everything we need, stator, gaskets, assorted parts like motor mounts that should be replaced while we have the motor out of place. The bike was neglected before he bought it and we seem to find more parts that ought to be replaced whenever we do anything.

So here are the ideas on which I need feedback. With only two phases, the rectifier puts out enough power to maintain the bike just a little above adequate battery voltage (12.2-12.4V), but (when I believe the fan kicks in) the voltage drops below 12.0V to 11.9 or 11.8 at idle. I would be comfortable that the bike will keep running and restart if we could keep the voltage above 12.4 or so at all times. So I tried moving all the light bulbs and headlight and we get 12.8V or so. The coils themselves seem to only consume an amp or less each. I measured the loads of the headlight and fan to both be ~4 amps and I imagine the six or so light bulbs will consume another 2 amps or more. My first idea is to drop the load on the system in terms of the lights. LED's should help some. I don't know what to do about the headlight or fan. Does anyone know more efficient versions of these? The other idea is to bump up the power I get from the two working stators, I would hope to get for 10-20% more, and think that would be enough. What would you guys think of lower input impedance step-up transformers on the working phases, lower compared the rectifier. This would increase the AC voltage into the rectifier and thus the DC output. The question is whether the working phases could handle the greater current.
 
#24 · (Edited)
First ,check the stator from leg to leg and not to ground,Voltage between 50 to 70 VAC should be present when checked between any and all combinations of the three leads,checking to ground is not an accurate measurement of the stator output.

With the stator unplugged at the bullet conectors,the only test from stator to engine ground should be for shorting of the windings to the engine block with your dvom set on the ohms scale with the engine off.

Tests between each lead to ground should read infinity or OL and no higher than .3 OHMS if memory serves me correctly,any more continuity than this should indicate a shorted winding in the stator.I would test for AC output as described before moving on top more complicated procedures or spending any more money.Tests should be performed at around 3000 rpm.

Also I would ask if you replaced the R/R with an OEM brand unit or one of the chinese replacement aftermarket ones,they are cheap for a reason.I would prefer a used Shindegen unit to a new aftermarket made in china,several on here have experienced very short life with both R/R's and stators when purchased from aftermarket suppliers most including me have bought used low mileage factory units (several interchange from various Kawasaki models) on ebay for cheap with good luck.

I hope this helps pinpoint the problem.
 
#25 ·
I'm afraid there is no way around it - you need a new (or good used) stator. If one stator leg is shorted, you won't get much power from the remaining two legs, no matter what you do.

Think of a transformer. If you short out the output winding, it looks like a short circuit on the input side too. If you had three similar output windings, the other two would be useless too.
 
#27 ·
I agree ,if the stator is shorted.He needs to check for proper voltages between the leads with engine running,not from Phase to ground .It is probably shorted,but that is best checked with the engine of with a continuity test.Both tests are called for in this case.

pappa is sharp on these things,but I read in your test procedure you tested from phase to ground when testing voltage rather than from phase to phase when testing voltage.

Another red flag to me is when the R/R was changed the voltages changed and then dropped again.it is only fifteen minutes work to double check the stator output Phase to Phase ,which is the only accurate way to measure Three Phase output.

And again if an individual set of windings is shorted to ground pappa is right,the whole stator is bad even if the voltages are right.

When we are talking a stator change,I am a "measure three times and cut once" type.
 
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