NC700X Hard to Start Intermittently

[MZ5]

Thanks for posting this, treybrad. I'm experiencing exactly the same thing with my NCX lately. This morning's start was the most recent example. I'm accustomed to the bike starting after a specific duration of cranking sounds, but sometimes it takes 3 times that long, or sometimes it just doesn't start until I release the button, pause, and try again. Once it took two pause-and-re-try cycles, though the duration of each start attempt was very short that time. It's been doing this on an unpredictable schedule for weeks for me, as well.

My area is like yours in that it will be unusual for us to get below 70F again at any time before fall. I do not have a voltmeter on my bike, but I'm starting to think I should. Phoenix (where I work) tied the record yesterday at 110F, and it's supposed to be about the same temp all week and weekend. I have AMA help available, but I do NOT want to be sitting on the freeway, frying, waiting for them to show if the bike quits. Even if the battery's shot, I don't _believe_ the bike will die outright while cruising down the freeway, but I don't know for sure.

BTW, I experienced my best-ever mpg over this past weekend on a ride with Dad through some very high (and relatively cool) country. I was well into the low 80s, whereas I'm normally at 71 - 75 mpg pretty much all the time. It did the slow-start thing once during the ride, but that was down low in the warm area, not up high in the cool.

 

[treybrad]

Thanks for posting this, treybrad. I'm experiencing exactly the same thing with my NCX lately.

Well, I'm sorry you're having the same troubles, but I'm glad I'm not the only one

Either this bike is particularly fussy about a fully charged battery, or maybe there's something to the temp sensor thought.

How many miles do you have on yours, and when did you last check the valves? Have you replaced your air filter? I did about 5k miles ago... I need to go trace my footsteps and make sure I didn't jiggle the airbox sensor loose, or anything else.

Just started doing it out of the blue for you?

trey

 

[MZ5]

I have just over 18k on the bike. Last valve check (the second one I've done) was at about 16k, from off-the-cuff memory. I have changed the air filter, but that was a few thousand miles ago; probably at 12k.

Yes, it just started doing it out of the blue one day. I can't say exactly when; I didn't make a mental note because it didn't do it the next time. Like you describe, it's random. I can't count on it being a first thing in the morning issue, nor a mid-afternoon issue. I can't count on it being a cold-start nor a hot-start issue. I commute on the bike most days, so it doesn't sit unused much.

I do have a few Honda electrical accessories all wired in by the dealer pre-delivery, plus some aux LED lights I wired through the Honda accessory harness and connector. I have aux horns, whose relay I wired directly to the battery. So, nothing can draw power once the key is off, unless the horns' relay was to fail in a peculiar way, which should alert me by sounding them.

**EDITED TO ADD:**
This has happened with 2 different sets of spark plugs, of different type and manufacturer, so it's not that.

 

[SergeantChuck]

This is what is strange to me as I read this thread. Maybe someone can make this make sense to me. If this is happening because the battery is low on a charge or dying wouldn't cranking it over and over again kill the battery even more? Thus make it even harder for the bike to want to start? Probably a dumb question but just throwing that out there?

 

[Ruggybuggy]

Not true on a permanent magnetic alternator.......it's output is 100% all the time and the excess power is sent to ground when not used to run the vehicle and charge the battery. No extra strain is put on the alternator or regulator in this type charging system.

Name a currently produced motorcycle or automotive application?

 

[Ruggybuggy]

This is what is strange to me as I read this thread. Maybe someone can make this make sense to me. If this is happening because the battery is low on a charge or dying wouldn't cranking it over and over again kill the battery even more? Thus make it even harder for the bike to want to start? Probably a dumb question but just throwing that out there?

I really don't think it's the battery either but the OP wants to eliminate it as a possibility.

 

[L.B.S.]

Name a currently produced motorcycle or automotive application?

? All motorcycles that I'm aware of except I believe the Honda ST1100, 1300, maybe Goldwings, and (some?) BMW Boxer bikes, have permanent magnet stators which produce 100% all the time, and shunt excess unused to ground.

I've never seen or heard of a car using this style of alternator.

 

[Ruggybuggy]

? All motorcycles that I'm aware of except I believe the Honda ST1100, 1300, maybe Goldwings, and (some?) BMW Boxer bikes, have permanent magnet stators which produce 100% all the time, and shunt excess unused to ground.

I've never seen or heard of a car using this style of alternator.

Well I learned something today. How does the Honda regulate the power output?

On my snowmachine it dumps back to ground with a regulator.

 

[Deleted member 1183]

I had an issue similar to this with my KTM 690 recently. It was an absolute pain to start from cold and sometimes if allowed to cool during the day, could also be troublesome. Up to about 20,000Kms it had been trouble free. My trusted tech took the problem on board. All and every aspect was checked and found to be in order. Then he started looking at the injector. He took it out and ran compressed air through it. That cured the problem for s short while, but it came back. However he now knew for sure that the injector was the problem. He replaced it with a new one and there hasn't been a problem since. I can now leave it sitting for weeks and with just a hint of the starter button it fires up as it always did. Have a look at that aspect.

 

[L.B.S.]

Well I learned something today. How does the Honda regulate the power output?

On my snowmachine it dumps back to ground with a regulator.

Same; with a regulator/rectifier, (aka R/R)

The unfortunate part of this design (isn't there always a downside, lol?) is that things get very hot. Connections can melt, stator winding coatings can melt and short out, they for the most part are a royal pain in the butt to try and remove and replace, and are quite expensive.

You should see all the "another burned up stator out of warranty" threads on the BMW F series bikes through out the 'net...

Not to single out the beemers, my CX500Turbo went through them like candy, and boy howdy it sucked to replace those ones! I did three and was working on my 4th, before we finally parted company.

Interceptors are renowned for having R/R problems too.

Hey, don't feel bad, I just learned from 670cc about left hand mirror thread adaptors today, lol

 

[showkey]

Well I learned something today. How does the Honda regulate the power output?

On my snowmachine it dumps back to ground with a regulator.

Edit: typing the same time as LBS


On the PM alternator voltage control and the dump of excess power is handled at the regulator. Years back the the regulators on these systems failed on a regular schedule usually due to heat. That has been resolved with a better regulator.
These systems are not real efficient and wasteful because of the heat but they are cheap and get the job done. Because of the wasteful design and managing heat this system is not used on cars or big motorcycle but need to generate a lot of power.

Edit......part of that fried stator deal is it sitting in really hot oil..(sorta like deep fried stator).....so the insulation on the windings gets compromised over time and shorted junk stator is the result.
That's when they started putting car style air cooled alternators on ST and GL. And other big bigs.
I have two new stators for my 500 turbo in reserve since they are discontinued part from Honda, aftermarket has filled the gap but can suffer from the same design compromises.

 

[Mike Cash]

My son's bike is a 1988 Honda VTZ250, which I learned after we bought it is notorious for frying regulators. Honda installed it a couple of inches behind the rear cylinder head, in an area with poor air flow, and put no cooling fins whatsoever on the regulator. Replaced one back in January, moving it and velcroing it to the inside of the left side cover for better air flow, and told my son to get some computer heat sinks to mount on it before spring. He didn't, and the first trip he took more ambitious than his usual thirty minute ride to school left him stranded in the mountains with a fried regulator.

So I hit the auctions and found yet another OEM regulator and ordered another battery to replace the one ruined getting the bike home again. This time I moved the regulator to the passenger peg bracket....completely out in the airstream and nowhere near the engine, made some homemade wiring to hook it up, and we headed off to the PC store to scrounge for heat sinks.

So far, so good.

 

[Old Can Ride]

I have had this problem on my NC7. Took me a while to figure it out. I was in the middle of a trip going cross country. I pulled every one those fine aluminum connections apart, but a little dielectric grease on every one of the bike's connections. Put every connection back together, and bingo the problem was gone to never, never land. Corrosion just loves those aluminum connectors. Takes so much longer to trace the system to find the short, than to just dielectric grease all the electric plug connections..

 

[Ruggybuggy]

Hey, don't feel bad, I just learned from 670cc about left hand mirror thread adaptors today, lol

Ya now that I think about it I should have know this. Just having one of those sh!t days at work and it was coming out in my post. Can't seem to do anything right today. Even dropped my helmet off my mirror getting ready to come home tonight.

 

[kungfoo222]

Here's a silly question: Were you holding the clutch in when trying to start it? Mine does the same thing if I don't pull the clutch, even when in neutral. As soon as I learned that, it always starts right away without a problem.

 

[treybrad]

Here's a silly question: Were you holding the clutch in when trying to start it? Mine does the same thing if I don't pull the clutch, even when in neutral. As soon as I learned that, it always starts right away without a problem.

Hmm, interesting. I usually click into neutral and don't use the clutch. That'd great if it were that simple, I'll give it a shot, thanks!

My double prime theory is busted. The last couple times it needed an extra revolution or two doing that.

trey

 

[SergeantChuck]

Here's a silly question: Were you holding the clutch in when trying to start it? Mine does the same thing if I don't pull the clutch, even when in neutral. As soon as I learned that, it always starts right away without a problem.

I wouldn't think that should be required but interesting to see what happens. I start mine while is on the center stand and I'm nowhere near the clutch. Daily

Samsung Galaxy S4

 

[showkey]

I never use the clutch when starting..............do not think that theory will hold up ?????????

If I was at the dealer and ask to look at this. ( fix it) .............I would do a cylinder leak down test .........specifically looking for valve leakage from excessive carbon build up. The theory after it starts the carbon as much less effect on compression compared to cranking compression. Just a test.........to confirm .........cylinder leak down is better test than conventional compression test.

If I did find cylinder leakage I would run a full bottle of techron to one tank, this would also clear injector crud build up..........I am not a sea-foam lover.

I assuming this condition has been occurring over several weeks and many tanks of fuel. Right ???

 

[treybrad]

Since we just had a post about following up on our problems, figured I'd circle back to this post. I still don't have an answer, but it's stopped doing it for all intents and purposes. Once every week or two it'll take an extra revolution or two to fire up, but it hasn't done it like in my video in a month or more.

I haven't really done anything. I ran some fuel cleaner (Seafoam) through it, but I'm not sure it did anything. It was still slow to start for a week or two after that, but it's gradually gotten better to the point of I really can't remember the last time it did it. I was going to check the valves again before a long trip I have planned in a few weeks, but at this point I'm not going to and just wait until I get home.

Maybe it was something with the weather/temperature? It's so hot now, our lows are in the mid to upper 70's. If it starts doing it again this fall, I'll have to revisit all of this...

MZ5 -- did you ever find anything out since yours was doing it too?

trey

 

[Deleted member 1183]

Your use of the fuel cleaner suggests to me that the injector was at fault all along. My bike starts first touch of the button in all weathers and all seasons regardless. There is no variation whatsoever. My 690 gave problems after 22000kms. I tried the fuel/injector cleaner. It worked for a few startups but the problem returned. A replacement injector cured it. However others with the same bike used other brands of injector cleaner with success. If yours gives problems again, I again suggest replacement of the injector. They are very delicate instruments and can be trouble free mostly but when they do give trouble they can be a real nuisance. I also had injector issues with one of them on my Toyota Rav and it is a diesel.