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Discussion Starter #1
Looking for some help tracking down an issue my bird is having of late. Was on my way back home on a 2900 mile trip and about 300 miles from home my speedometer dropped to zero on me. Having had my stator go out ~6000 miles ago on a previous trip I assumed the worst, and that my charging system was toast but figured I was relatively close to home and every mile I could get closer to home would be one less mile to trailer it back for repairs so I pushed onward. Ended up making it all the way home without it ever dieing. On the way I figured out that as long as the engine speed was kept up above ~5k I would still get a speedometer reading. But like clockwork, if the engine speed dropped down I lost my speedometer again, so I ended up riding home that last 300 miles using mostly 4th and 5th gear.

Having arrived safely at home I started tearing into the charging system which I no longer really believed would be the problem. Having ridden home 300 miles, and finding my battery fully charged upon arrival, it didn't seem likely to be the source of the problem. From my mediocre electrical ability I believe I'm getting proper voltages and have been unable to track down any components out of spec.

Having been unable to find issue with the charging system I moved on to thinking it was just the speedo sensor, since I'm only having issues with the speedometer, and odometer but only when the speedo reads zero. After tearing the bike apart as far as I was comfortable I checked all the connections for any corrosion and checked the voltage readings on the sensor and wasn't able to find any issues. Ended up cleaning it all up while it was apart and putting it back together, and put in an order for a new speedometer sensor figuring it was the only thing that made sense at that point.

Been riding it for a few weeks waiting on the sensor to show up with only an occasional intermittent issue with the speedometer acting up which goes away after a few seconds. Appears to be mostly when in 6th on the interstate with the engine speed sitting below 4k, but again, it's been going away after a moment on its own. It does however act up on occasion with the engine speed up higher going around town at lower speeds but it happens much less often under these circumstances. Lately though, I've been noticing it feels like I'm chopping throttle when it happens for just a split second before going back to normal, but haven't been able to isolate if its my imagination or what exactly is going on since it happens so quick, and so intermittently that I'm unsure of what is happening. Thought it might be something simple like a link in my chain binding up momentarily or something dumb, but I cleaned and re-oiled the chain and wasn't able to find any issue there.

Finally got the new speedometer sensor in yesterday and installed it last night, but when I tested the bike today it is behaving the same as it did with the old sensor. Rides fine most of the time but every once in a while the speedo reading will drop, and then come back a moment later.

I'm lost as to what it could be at this point. I'm not an electrician by any means but an electrical problem is starting to seem less likely to be the culprit unless someone can point me in a new direction I may have missed.
 

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My initial thoughts on this are that your charging output is down on ooomphh. These bikes are well known for crap charging output at low revs (although low normally means <2500 revs), and if run at low revs continuously, the battery will run flat, resulting in component shut down (in your case the dashboard).

You mentioned "Having had my stator go out ~6000 miles ago on a previous trip".

Does that mean that you replaced the stator (or anything else)? If not then try the following:-

1. Voltage across the battery - should be c. 12.7 V (fully charged) with engine off
2. With engine running < 2500 rpm (ish) should be c. 13 V
3. With engine running at 5000 rpm you should be getting c. 14.5 V
4.
Turn your headlights on with the engine revving at c. 5000 rpm. Does the voltage at the battery drop below 13V? If so you've got a problem.
5.
Your headlights should get brighter as you rev from tickover (the stator should increase output with revs, with a corresponding boost through the whole system)

If any of the above tests fail, then you have an issue with your battery (least likely, although a load test would tell), your stator (easily tested) or your regulator / rectifier (again can be tested with a voltmeter). You need all three of these components to be good, or you'll get constant problems.

I had a similar problem with my reg / rec resulting in too little volts making it back to the battery, and eventually running the battery flat.

Hope this helps.

 

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Have you checked the PCB tracking on the rear of the clocks (and associated plug), on 99 Birds they are exposed and whilst you probably don't suffer the corrosion issues we do here they are getting a little old and it is not unknown for them to cause issues.
 

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Discussion Starter #4
My initial thoughts on this are that your charging output is down on ooomphh. These bikes are well known for crap charging output at low revs (although low normally means <2500 revs), and if run at low revs continuously, the battery will run flat, resulting in component shut down (in your case the dashboard).

You mentioned "Having had my stator go out ~6000 miles ago on a previous trip".

Does that mean that you replaced the stator (or anything else)? If not then try the following:-

1. Voltage across the battery - should be c. 12.7 V (fully charged) with engine off
2. With engine running < 2500 rpm (ish) should be c. 13 V
3. With engine running at 5000 rpm you should be getting c. 14.5 V
4.
Turn your headlights on with the engine revving at c. 5000 rpm. Does the voltage at the battery drop below 13V? If so you've got a problem.
5.
Your headlights should get brighter as you rev from tickover (the stator should increase output with revs, with a corresponding boost through the whole system)

If any of the above tests fail, then you have an issue with your battery (least likely, although a load test would tell), your stator (easily tested) or your regulator / rectifier (again can be tested with a voltmeter). You need all three of these components to be good, or you'll get constant problems.

I had a similar problem with my reg / rec resulting in too little volts making it back to the battery, and eventually running the battery flat.

Hope this helps.

After letting the bike sit overnight the battery voltage was showing 12.79 V initially. When turned on it obviously drops initially then recovers to 14.48 V at idle, when revved at all it drops to around 14.2 V. My model always has the headlight on, and I didn't notice it getting any brighter while playing with it.

I was playing around trying to check the stator output but apparently I wasn't doing something right as I was getting some really weird readings that couldn't have been right. Again, I'm not an electrical expert so not sure how precisely one would test the stator output.

Have you checked the PCB tracking on the rear of the clocks (and associated plug), on 99 Birds they are exposed and whilst you probably don't suffer the corrosion issues we do here they are getting a little old and it is not unknown for them to cause issues.
I have the front back together from taking the bird out yesterday or I would snap some pictures of it to post up. I did however have it apart about a week ago checking for just that sort of issue and when I looked it over I couldn't find any visible issues with it.
 

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I was playing around trying to check the stator output but apparently I wasn't doing something right as I was getting some really weird readings that couldn't have been right. Again, I'm not an electrical expert so not sure how precisely one would test the stator
Make sure the meter is set for AC voltage, not DC. You should be seeing somewhere in the neighbourhood of 50 VAC across all three pairs when rev'ed up. The readings should also be fairly consistent across all three pairs.
 

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Discussion Starter #6
Make sure the meter is set for AC voltage, not DC. You should be seeing somewhere in the neighbourhood of 50 VAC across all three pairs when rev'ed up. The readings should also be fairly consistent across all three pairs.
Haha, genius! Reading very close readings between the three, roughly 40 VAC @ 5k rpm.
 

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Discussion Starter #7
2014-06-20 06.14.35.jpg
PCB doesn't have any breaks in it that I can see, tested the 3 speedometer related points and no perceivable issues between the contacts and the pins.

Didn't take a picture of them but the 10pin connectors have no corrosion on them at all, only sign of their age is a little dust on the rubber sleeves that protect them.

Starting to wonder if I'm even going to be able to find an issue with it in the garage since the issue is so sporadic when on the road. Any additional thoughts are much appreciated.
 

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I have the same problem with my digital dash. I'm assuming the analog dash has the same wiring. I figured out what was going on. At times the trip meters and clock would reset. Then the tach would drop out or the speedo would drop out when I started it. All I have to do is shut it off and then back on and all would be fine.

There is a ground block, like the one on the side that need the wires soldered together, in the front wiring harness. I had it apart when putting in HID lights. I wanted to switch them using the ground. I found out that it would back feed thru the grounds and that each gauge section had it's own ground at the block. If they don't make contact then your particular gauge won't work.

So take a look at that. It's covered with tape so you'll have to undo the harness tape to get to it. You'll see it on the drivers side of the harness connected to the cowl bracket. It's a bulge in the harness and not the blue connector (mines blue) for the gauges.

Like I said I'm assuming your 99 and my 01 use the same harness.
 

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Discussion Starter #9
Checked the connection block you were referring to and found it looking pristine as shown below, so just put it back together and taped it back up.

2014-06-21 10.30.36.jpg

The port on the back of the bike however was a different story. Although I haven't had any issues with my FI light to date, while I had it apart I went ahead and did the loom fix to save a headache down the road.

2014-06-21 10.38.41.jpg

Then while double checking the charging system I found a wire that had apparently come apart on the stator side of the plug, so got that fixed. Not sure yet if that will have any effect on my issue but it couldn't have been helping it. So got that taken care of.

2014-06-21 14.37.42.jpg

And then finally, I checked for a voltage leak and found a definite out-of-spec draw on the battery. My honda manual states that resting draw should be at most .2 amps, yet when I tested it I found it to be .57 amps. Played around with it a bit trying to figure out what was causing the draw, and only thing that had any effect was unplugging the gray plug going into the PCB. At which point, the battery draw drops to zero. Plug it back in and instantly back to drawing .57 amps. Considering the only thing that should be live is the clock, I'm not sure what the problem if there really is one could be. Hopefully someone who knows more about the wiring that interfaces with that plug can shed some light on it. Oh, and I did all the testing for a voltage leak with everything aftermarket disconnected, and then again with it connected and it doesn't change it so it's not of my doing this time!
 

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How certain are you of the calibration of the meter you're using?
 

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Discussion Starter #11
Well the meter is less than two weeks old and has matched a voltage meter I have. Don't have another one to compare the current reading to though.

Sent from my SM-G900V using Tapatalk
 

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Well the meter is less than two weeks old and has matched a voltage meter I have. Don't have another one to compare the current reading to though.

Sent from my SM-G900V using Tapatalk
Ok. Not trying to be a jackass here, just trying to see all the angles: what kind of meter is it? I've had economy meters give me very inaccurate readings when compared to the ones I use for diagnostics at work, particularly when measuring minutiae.
 

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Ok. Not trying to be a jackass here, just trying to see all the angles: what kind of meter is it? I've had economy meters give me very inaccurate readings when compared to the ones I use for diagnostics at work, particularly when measuring minutiae.
It's just a cheap Craftsman meter I picked up from Sears until I can afford dropping more coin on a good one. It may be inaccurate, may not be, can't afford to get another one to compare it to right now.

Although on the bright side, the wiring fixes I posted seem to have fixed the speedometer issue I was having. Or at least appears to, since it hasn't come up in around 150 miles of riding since I put it back together. Still a little paranoid about the voltage leak that my meter at least is saying I have. Although with it running fine right now I'm not sure I want to start tearing into it a whole lot more for a ghost problem.

Coming from doing programming work for the last 12 years I'm just starting to get into doing mechanical work. Don't really have any issues with basic mechanical work but wouldn't delve into an engine rebuild or anything quite yet. Although electrical is proving to be the end of me as I have had very little experience with it to date, so having to learn a lot of basic stuff yet. I'm trying to get up to a level of competency where I can effectively work on something as 'simple' as my bird. I just can't afford to keep paying shops to look at it when you can't find anyone even at the Honda dealers that are familiar with them anymore. And with the mileage I've already put on it, and plan to, it's going to be needing a lot of maintenance! :)
 

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It's just a cheap Craftsman meter I picked up from Sears until I can afford dropping more coin on a good one. It may be inaccurate, may not be, can't afford to get another one to compare it to right now.
I wouldn't worry too much about it unless your battery is going flat over the course of a few days to a week. Even mine will lose enough charge that it won't start if left sitting untendered for a month and my current draw is well within spec.
 
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