V light on early

Out for a ride today and v light came on, it not done that since 16k miles.
Currently on 21k miles, belt changed at 16k by myself (oem too), 25g Dr P's fitted about 3k ago.
Quite a hot day (for the uk), two up (so a fair bit of weight on the bike), mostly a bimbling along day but I had just subjected it to a brisk full throttle 50 to 80mph acceleration to clear some traffic up a hill.
I've reset the light and will monitor it before I unbutton everything.
But what do you all think? Just a one-off bit of belt slippage? Or something else?

A visit by the belt light fairy. Reset it and forget it.

Ah, sound mechanical advice, I think I'll take it, Thanks Bud :-)

Hope a reset sorts it, something we live have to live with these days, electrical warning lights coming on.
Very common for F1 lights registering an error code because of a cough it the engine system, nothing wrong with the engine just weather conditions or driving error.
Worth checking the tightness of the battery terminals and doing a re-charge if you are waking the bike up after a winter lay-up.

V light---just re-set and ride----it is only counter of miles, not belt condition. I always changed belts based on miles from odometer. Know your machine---things like V light are just add ons

Another vote for reset & forget  IIRC some years back another member concluded that his/her light could come on due to belt slippage

steve_h80 wrote:

Out for a ride today and v light came on, it not done that since 16k miles.
Currently on 21k miles, belt changed at 16k by myself (oem too), 25g Dr P's fitted about 3k ago.

IIRC (miracles do happen), others have said a change in sliders have caused some problems. Of course I may be wrong.

I'm with the reset and forget crowd.

Have you cleaned the variator filter every four thousand miles? It does get neglected and can cause problems. It maybe called crankcase filter but, it covers the variator.

Yep is was cleaned last time I had it open.
I'm going with rest and forget for now and I'll most likely just take it for a thrap soon and see if it repeats. I expect curiosity will get to me though and I'll unbutton everything again.

I'm sure it will be fine, it's just a bean counter.

I don't know if it's just a bean counter or not. Studying the wiring diagram the V light is hooked to the Meter CPU, which has a drive belt in signal coming from the ECM. There is no reason to have a dedicated signal on the P/O wire from the ECM for a bean counter that just keeps track of mileage. My educated guess is the ECM compares the signals from the cam position sensor, TP sensor and wheel speed sensor. And if the ratios are not within a pre-programmed range it sends a signal to the Meter CPU to turn the light on. It may also keep track of mileage. But it's definitely doing more than that.

Indeed Chris, that would explain why it would come on due to slippage

I've never had it happen, but there's numerous reports I've seen where the light comes on, the rider resets it, and a few days later it's on again. The Meter CPU obviously keeps track of the mileage as it also controls the speedo and LCD. The service manual is not real clear on the topic. But the wiring diagram, with dedicated circuits for FI and V-Matic warning looks like a rudimentary fault indicator circuit. The ECM evidently does not store DCT's, but instead triggers a fault based on pre-programmed parameters that must be met being out of range.

I do know, for instance. the FI light can be triggered by a spark plug misfiring on the models with catalyst and EGO sensor. And it will automatically clear if the fault does not reoccur. It is an n-alpha mapped injection system. The basic variables are the engine speed (n) and the throttle angle (alpha), combined with inputs from several other sensors with a "map'. Being both the FI and the V-matic circuits appear to be the same, I'm almost certain the V-matic is doing the same thing, with the exception that once a fault occurs on the V-matic 'map' it triggers the Meter CPU to keep the light on until reset.

The web tells me v light also comes on if it detects a variance between the pulleys outside of a certain range, which is why I'm suspecting a bit a belt slip. And if that's going to happen fully loaded, full throttle and uphill is when I would expect it.
We will see...

It's never been verified that I know of, but I wonder if changing the variator rollers might cause it to come on? I think the stock rollers are 28gr. So if you have 25gr sliders, they are not going to have the authority on the variator under heavy acceleration to overcome the spring in the torque sensor (rear pulley). So if the system "see's" higher rpm than normal vs throttle opening and rear wheel sensor speed, due to the mods to the variator, it may "think" the belt is worn or slipping when it's really not.

Both me and my wife had 32gr rollers (not the sliders) in our 2002's and we now have those in our new SW's too. Those actually cause it to shift up quicker. I sold my 2002 when we got the Harley but my wife kept hers because it's her favorite bike off all time. She had 70+ thousand miles on it when she sold it and to my knowledge (unless she reset it and never said anything) the V-light never did come on in her bike. I know she had 40,000+ miles on the belt in it when she sold it. But she is not a hard rider - she's pretty gentle on stuff. I doubt she ever used full throttle on her bike in all the time she rode it. We never even put brake pads in it, and she gets 10,000+ miles out of a rear tire.

How does one reset it?

Hold down both buttons and turn the key on and hold the buttons until the light flashes.

Chris Olson wrote:

Hold down both buttons and turn the key on and hold the buttons until the light flashes.

That was fast.  I got my answer in 3 minutes. I just did a search and found the answer and was going to return to say "never mind," but instead, I will say thank you.

Here is what I was going to post on a copy and paste:

to reset the light hold down the clock/trip buttons for 5-6 seconds as you turn on the ignition, this resets the V light AND millage on your belt.

Just the info I needed!  Once again the forum comes up trumps.  Thanks.  

My V light came on this evening.  A bit of a shock as I've had the bike years and never previously had any issues with it.

Going through the procedure described above, I turned the mode to odometer, and it read 16,005 miles. That explains it! I had the belt changed early a while back as I was anticipating a long European trip (sadly, Covid put paid to that idea), and it seems the Honda dealer that did the change omitted to reset the counter.  

I now look forward to another 16,000 trouble-free miles.  (He said, tempting fate!)