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Warm Start

348 Views 16 Replies 8 Participants Last post by  BlitzSchnell
My 2017 R NineT Pure starts just fine when cold, but after riding for a while, the bike fails to start unless I leave it off for 10 - 15 minutes.
Does anybody know why a bike will start when it's cold, but not when it's warm?
I replaced the batter one year ago, and the starter about one month ago.
There are no multiple clicks.
There is no emended attempt to turn over.
The bike will sound as if the batter is dead, and the instruments will slowly die down when I try to start the bike after running it.
This is annoying when I stop for gas and get stuck at a station for 10 - 15 minutes each time.
I would like to have some ideas about what is going on before I shell out more money to the expensive dealership.
Thanks in advance.
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When cold, does it come straight from the charger?

Maybe the dynamo is faulty?
Start by measuring the Alterntor (Dynamo) like @Chopper_Bob mentioned. Does it charge the battery?

A battery will gain some of it's "Power" back when you leave it un-used for a while. This would explain the situation if you turning the bike off; waiting 10-15 mins and it then starting again.

I see you replaced the battery and starter. But this still does not warrant anything. Batteries can go bad within months. Measure to know.. can be done with a cheap multimeter.
Why did you replace the alternator by the way?

If not the battery/alternator; could also be a vaccuum problem.. But then it should not happen after a gas stop since you open the gastank to do it..
When cold, does it come straight from the charger?

Maybe the dynamo is faulty?
I don't keep the bike on a charger because I ride at least once every week.
When stating the bike cold, it starts up like normal, no issues, no extended effort.
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Start by measuring the Alterntor (Dynamo) like @Chopper_Bob mentioned. Does it charge the battery?

A battery will gain some of it's "Power" back when you leave it un-used for a while. This would explain the situation if you turning the bike off; waiting 10-15 mins and it then starting again.

I see you replaced the battery and starter. But this still does not warrant anything. Batteries can go bad within months. Measure to know.. can be done with a cheap multimeter.
Why did you replace the alternator by the way?

If not the battery/alternator; could also be a vaccuum problem.. But then it should not happen after a gas stop since you open the gastank to do it..
I never replaced the alternator.
I took it to the dealership, and they did the following:
  • Replace starter with new starter
  • Renew throttle body with new muffler clamp and new intake manifold

I ruled out the battery because it starts cold, but not warm after riding.
I will do a test on the battery and alternator as you all recommend.
Sorry i miss-read the Alternator as Starter..

Yeah; measure first.. i wonder what comes out.
I had a similar experience, stalled in traffic a handful of times over the summer (~30°c ambient) and starting the bike was very reluctant to start. Getting even two rotations outta the starter was a tall order.

Told the dealer about it, they load tested to battery when cold/when idling/operating temp/when hot and the volts were down to ~10v or ~9v, something nuts like that. I'll have to dig up the invoice to check.

But, lucky me was covered by warranty. Otherwise was a $500+ service. $335 just for the battery. Egad, friend!

Edit: Found the Invoice
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Can you check the voltage on your display?
Since it's starting fine cold, I'd look at he wiring from the battery to the starter and the starter to ground first. All of those were loosened recently and heat may be making them a bit loose from expansion. Sightly loose connections might handle the current when cooler because electricity flows better when colder.

If all the connections are tight, go to any auto parts store and have them test the battery. They can check it under a load.

Does the bike respond at all when it's failing to start? Do you hear nay noise at all or notice lights dimming? If none of those things happen, you might want to get someone to check the starter switch.
Since it's starting fine cold, I'd look at he wiring from the battery to the starter and the starter to ground first. All of those were loosened recently and heat may be making them a bit loose from expansion. Sightly loose connections might handle the current when cooler because electricity flows better when colder.
My thoughts too, I'd be checking connections at battery, starter etc, perhaps undo them, clean with a scotchbrite pad and then re-connect.:cool:
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Its the battery! What battery did you install as a replacement? How old was the replacement battery when you stuck it in? There's a lot of old sat on a shelf batteries out there that might look like a good deal but soon prove to be a waste of $$$ and time to buy them and install. Check the CCA and age of the newly installed battery and go from there.
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Can you check the voltage on your display?
Yes, I will do that today.
Thanks for all the warm leads (see what I did there?)
You all have given me A LOT more information than the mechanic!
I'll run the tests over the weekend and report back soon.
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Any Mechanic with some kind of functioning brain should know all this.

Im not even a mechanic.
Any Mechanic with some kind of functioning brain should know all this.

Im not even a mechanic.
Yes, but dealers employ technicians.
Mechanic and Technician are not the same. Learned that the hard way lol
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Yes, but dealers employ technicians.
Mechanic and Technician are not the same. Learned that the hard way lol
Ah yes; if computer says it's fine.. it 100% is.

-Technician
Great puzzle, lots of good ideas too. Most likely it’s an electrical issue. If you boost the battery with a jump does it restore the electrical system to normal and turn over appropriately ? Some aspect of what’s required to start the bike is being modified by the heat after running for a bit. Compression is the primary change that comes to mind because it will increase a bit after warm up. It will make it just a bit tougher to turn over. How many miles on this machine ? Is it broken in, no longer burning any oil etc …. ? Has it ever been re-mapped, dyno’ed or super tuned. ………………. I think I agree that it’s one of three issues … All are electrical issues …. Battery (or connections) … starter problems (or connections) … dyno (or connections) ……. Or … long shot … contact points in the solenoid of the starter …. I’m probably making something way to complicated out of this that will turn out to be just a bad electrical contact …
Let us know how this dilemma plays out …… good luck …. Blitz
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