Yamaha YBR 125 check engine light comes on at speed

[dublinclontar...]

I've got a standard 2010 (FI, 12k on the clock) model YBR 125, recently just replace the rear brakes chain n sprockets, gotten a battery charger, cleaned the air filter and spray painted the exhaust pipe.

This is my first bike and I'm probably a sap for doing this but I use premium petrol and fully synthetic oil (changed 250 miles ago, nothing but the best for my little girl).

Commute 70 miles a day(35 each way) and this evening the check engine light would come on anytime I went over 60 on the speedo when typically I'd get up to 75 before "the beast" ran out of grunt.

The light wasn't flashing, i.e. staying on until I let off on the throttle a good bit to bring the speed back down.

Any ideas what the cause might be as I've not got a clue

[dublinclontar...]

Forgot to mention that the light also comes on after starting the bike, but goes away after a minute when I drive.

[ficedula]

Goes away after a minute?

Normally, it'd come on when you put the ignition on, then go off about 2 seconds later.

Obvious checks first: have you checked the oil level (and done it on an actually level surface)? How about the battery - you say you've got a charger, but have you checked the voltage?

A dodgy battery could make the ECU go a bit squiffy, so it's worth ruling out. Hooking it up to a charger regularly might keep it starting, but won't necessarily make it 'good as new'.
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Bike history: YBR125 -> XJ600

[stinkwheel]

Check your oil level before you ride the bike again.
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I did the 2010 Round Britain Rally on my 350 Bullet. 89 landmarks, 3 months, 9,500 miles.

[gavbriggs]

I have no idea really but is there a separate oil light? If not it could well be level or pressure?

Older cars used to have the oil light on for a brief period until pressure built up and this was normal.

Maybe a loose connector?

[dublinclontar...]

Normal operation for this bike is for the check engine light to turn on for a couple of seconds after turning the key.

You should hear the FI working, light turns off, then hit the electric start and the engine starts.

This happens but the check engine light will remain on after starting for one or two minutes if I ride the bike right away or splutter out after 2-3 minutes if left idle.

I've checked the oil on a level surface, it's at 90% full (i.e. about 10% below max)

Battery charger reads that the battery is at 13+volts and switches to maintain (as opposed to full charge) right away.

I'm going to take the seat off and check for loose wires.

[Pigeon]

I don't know what I'm talking about, but garage dude told me to not use fully synth oil in YBR.

Not just because it's a waste of cash, but "can create clutch slip" and "get past oil seals".

I know nothing.

[dublinclontar...]

I removed all the panels, seat to have a look at all the wiring.

Poked around a little but didn't find anything that looked like a loose wire, after putting it all back on I started it up, and wouldn't you know the check engine light didn't come on.

On my way into work this morning as well, blasting up the A13 at top speed (a blistering 80 on the clock which is...probably about 65 in real life), the light remained off.

Either I accidentally disconnected the check engine light or knocked a loose wire back in place but either way it's "fixed"

[Rogerborg]

If it comes on again, put a bit of electrical tape over it. Protip.

Well, you're not actually going to check the engine, and the oil is OK, so why not?
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[Dave M]

If it was me I would take it to a dealer yes a dealer to do a diagnostics check on it just in case there IS something niggling away that could end up being a more expensive job? I think it cost less than £30 to have this check done but make sure your with the mechanic when he's doing it in case he tries to pull a fast one on you!!! Use a semi synthetic oil of 10W40.

[YBR Ric]

I did an oil change using fully synthetic which was left over from my other bike - the YBR just drank it between oil changes.
I went back to semi and not needed a drop between oil changes ever since.

Never suffered clutch slip or any other cr&p/old wives tales associated with using [synthetic] motorcycle oil in a motorcycle engine,
just the effects of the oil pixie coming out of from underneath her mushroom at night and stealing some of it.

Just to clarify; engine check light is orange, oil check light is red.
Which colour is being illuminated?

[dublinclontar...]

[ADSrox0r]

Have you 'tinkered' with anything, ratios etc?

75 on a YBR is....impressive, they top out generally at 65 and that's with a tail wind.

[ficedula]

It wasn't too difficult to get my YBR125 to indicate 75, given a (very) long enough run up and a flat road.

I'm fairly sure it wasn't doing much over 65 in reality, but the speedo certainly went up to 75.
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Bike history: YBR125 -> XJ600

[dublinclontar...]

[cb1rocket]

Get a GPS on it and then see what speed it does.....?
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