800 XRT wouldn't start

[HMC]

Hi K1W1,
Yes you would think so, but I am not sure this is the full picture in this case. We have " After running for a minute I gave it some gas and it turned of again." which would suggest that at least the charge rate should be tested.
Regards HMC

[quigglie]

Would a near empty battery not cause the bike to shut down when giving throttle? After letting it run for a little while longer it kept running.

The bike didn't throw up any codes and the fuel pump primed as well.

Obviously the battery is part of the cause here, but I'm wondering whether it's just the battery that's the issue or if there's an underlying cause for the battery not working properly. A year old battery shouldn't be empty after a week of not riding. If it keeps acting up I'll just get a new battery, but only if there's no underlying stuff to fix first.

Just to note, there's nothing electrical that's been changed to the bike from stock aside from adding the Advmoto relocated indicators and it's had a big service done about three months/4000km ago.

[Stevie.P]

Originally Posted by quigglie

The battery is not even a year old. It read 12.5v when the contact is on. Around 11v when it was cranking.

Originally Posted by quigglie

Obviously the battery is part of the cause here, .... A year old battery shouldn't be empty after a week of not riding.

A classic mistake is to use battery voltage as a measure of condition. While it has relevance it is the amount of amps the battery can retain and provide that is the most important factor. A battery can still show the right voltage but only be holding enough amps, for example 20A, to power a light or two but not enough cranking amps (i.e 230A) to power the starter motor.

Also the age isn't a guarantee of condition, they can and do go bad. I believe you get what you pay for and so once (for my car) I bought the top of the range expensive Bosch Platinum battery with 5yr guarantee and it failed at 10 months old.

If the battery does manage to start the bike then the bike should continue running as the battery is only really there to power the starter motor and once running the alternator provides all the neccessary power, unless you have too many accessories and power demand exceeds the alternator output.

If you have a battery shop nearby you could fully charge the battery and then take it there and ask them to properly load test it.

[awjdthumper]

In principle, you can load test the battery by connecting a 55 W headlight bulb across it and see how long it takes for the voltage to drop to a particular level. In principle, the voltage should drop to about 12 V after 1 hour corresponding to about 50% of its capacity.

It looks as though the problem is being caused by the engine not being cranked over fast enough by the starter - if too slow, the ECU will not fire up the plugs. If it wasn't such a pain to get at the plugs, the simple test for this problem would be to check whether you are getting a spark as the engine is being cranked over. If this is the problem then it may be being caused by the starter motor power having degraded, By jump starting, the starter motor may have been receiving a higher voltage from the larger capacity car battery giving it sufficient power to fire up the engine. One other test that may be worth doing is to power up the starter motor directly from the battery to rule out a wiring or starter relay issue.

 

[Paulhere]

Originally Posted by quigglie

The battery is not even a year old. It read 12.5v when the contact is on. Around 11v when it was cranking.

Does anybody get better than 12.5v with ignition on? Or more than 11v while cranking? I certainly don't.

A duff battery would not show those figures & a struggling starter would drop the voltage reading way down.

Maybe the OP's multimeter needs checking, if it is the battery or starter causing the problem. When it starts, then stops, smacks of a duff battery, something not right with the figures.

Is that new last year battery an exact replacement for the original, not a budget job?

[quigglie]

Yeah the battery was replaced by the OEM Yuasa, bought new from a reputable shop. Fuel pump was priming every time as well.

I'll run some more checks once I have the time.

In the meantime a quick summary:
For the past few months the bike would only start on the second try when it had been parked for a while. The first time it would sound like it started but then stop. Second time it ran fine.

Then after a few months and not riding for a week the bike wouldn't start at all, unless hooked up to my car. After that, I hooked it up to a trickle charger for two days at work. Then it started the first try every time. Until today, when after not riding for two days it wouldn't start the first time but did start the second time.

[Paulhere]

You need to post up more info'.

When you say not starting, what exactly is it doing, eg is it spinning over on the starter at normal speed & holding the 11v while doing so? Post a vid up showing this.

[quigglie]

It's spinning the starter at a normal speed and holding 11v while doing so. Felt like it wasn't getting any fuel, spinning but not starting. Except it obviously had fuel and the fuel pump was priming.

Can't exactly post a video of an issue that's not occurring right now...

[Paulhere]

Maybe bad fuel.

[Paulhere]

Originally Posted by quigglie

It's spinning the starter at a normal speed and holding 11v while doing so. Felt like it wasn't getting any fuel, spinning but not starting. Except it obviously had fuel and the fuel pump was priming.

Can't exactly post a video of an issue that's not occurring right now...

So, what is not occurring right now?