NX250 Thread -- official ADV owners manual

[legends117]

I started working on my newly acquired NX250, and noticed my tool kit doesn't include a spark plug socket. Can you tell me if I need a special Honda plug socket, or can I use a standard socket? Thanks. - JD

[Jacl-Kampuchea]

Originally Posted by Orkodelamuerte

Yep. Out of nowhere, I get gas, air but no spark. I get ramdom explotions, and if i quit forcing the throttle, engine will stop. same as when you run out of gas.

It feels as if when engine is hot, the CDI pulse will not catch up with the revs, so it fails to get a continuous spark..

Id try a known good coil and rectifier before looking at the CDI. Start with the smaller, more likely issues.

Also, a bunch of people on here have listed as trick a for checking whether the CDI is faulty or not - "turn on the ignition and if the tach moves then it's probably not the CDI"

This is NOT correct at all. Myself and a few friends had a play around with broken CDI'S, working CDI'S and bikes with the CDI's taken out. Tach jumped every time.

[Orkodelamuerte]

Originally Posted by Jacl-Kampuchea

Id try a known good coil and rectifier before looking at the CDI. Start with the smaller, more likely issues.

Also, a bunch of people on here have listed as trick a for checking whether the CDI is faulty or not - "turn on the ignition and if the tach moves then it's probably not the CDI"

This is NOT correct at all. Myself and a few friends had a play around with broken CDI'S, working CDI'S and bikes with the CDI's taken out. Tach jumped every time.

By rectifier you mean this?


Coz if that's it, its a brand new one. I've seen that test for the CDI performed with the tach.. My tach moves when I turn the ignition, that proves (i believe) it works, but does not prove it doesn't fail. Plus, I must restate that my tach goes crazy when my bike is hot (that didn't come out right huh?!!)

Seriously, so I will try to check on the coil as u said.. any idea how to know if the rectifier (that thing on the picture above) is good?

[Orkodelamuerte]

While observing the coil with my monkey face for a while, I noticed I have a spark plug thats not what I am supposed to have on this bike.. I´m currently using an NGK CPR8EA-9, but according to the manual, I should be using NGK CR9EH9.

The question is, Can that single detail be the cause of my problem?

I´m soooo buying this spark plug first thing tomorrow...

[Dirtstar1]

Hey guys, I took the NX250 to the supermoto track today and had an awesome time. I managed to pass some people, lol but mostly held my own against the modern bike showdown. Lots of Ktms, crf450's, yz450's and a few wr250x's. let me tell ya, the drz400's were really surprised when I passed them. All on dot trailwings! Ok ok I did low side twice today, but no harm was done to the rarest plastic on the planet.

[scrambler66]

Originally Posted by Orkodelamuerte

This is what happens... Now that I finally got my bike back and runing, I'm having a new issue.

As soon as the engine gets hot enough to start the fan, I get short on spark, The engine will start failing and would not cease until I let it cool down a little.. If I go quiet and below 5k revs, then nothing but perfection happens.

Another thing that I noticed is that when that happens or is about to happen (the spark issue) the tach will go crazy, showing 3k revs when Im pretty sure I'm going 1.5k.. but dont know if related...

My final thought was that my CDI is bad... what do u say?

pd.: engine and carb are more than perfect... so dont focus on that.. My alternator has been repaired 1 month ago, and regulator is brand new.

Ok, I got two points: first, there are multiple symptoms a bad CDI could cause – as mine failed, the Nixie always didn`t start at first, but after wiggling a bit at the CDI wiring it finally started and the engine was running without any other problems. But I heard from many NX650 drivers (with almost identical CDI) that there are other possible symptoms, one of them is failing of the tacho. And since I’m a follower of Occam’s razor, I guess it’s actually the CDI (there is no side stand switch and I rarely heard of other electrical component failing).

But secondly, it’s a bit disturbing that you mention the fan. Sounds like the fan starts abundantly? This is rather unusual, it rarely happens with mine and nether at higher speeds. Only when I have to wait for some time in front of a traffic light, or with low off-road pace the fan sets in. So it might as well be an overheating problem (wrong spark plug?)

[fikse]

Orkodelamuerte: Get yourself a new plug. I dont know if there are difference for the plugs you mention, but correct plug is essential :-)

Dirtstar1: Fantastic pictures! And stories... ;-) Keep them coming

[Dirtstar1]

Full throttle powersports is having a dyno contest. Free to enter do I had them run the nx! Are you ready? 19hp! Lol totally stock with a new cdi box. All on stock gearing and oe tires.

[Orkodelamuerte]

Ok, I replaced the spark plug for the correct one. I must say that there has been a noticeable diference regarding the engine performance and heat control...

I read somewhere that depending on the temperature rate (or sth like that) of the plug, the heat will dissipate easier and therefore, performance improves in many ways...

Those many ways, are true, but still didnt solve my particular issue,,. when some real heat kicks in, spark fails..

It took longer to get the bike hot, but the problem is still there.

I did notice one more thing.. when I turn on the ignition switch (green light for Neutral), the CDI box makes a very quiet but high pitched sound, It goes off as soon as I turn the key to off. Dont know if thats normal, so would any of you be so kind to listen to your bike?

You dont have to put the bike apart; just get your ear close to the fuel tank and pay attention as you turn the key to ignition..

Thanks You all!

PD; Happy New year!!!!!!!!!!!!!!!!!!!!!!!!

[Honda Scoot]

Originally Posted by valvecrusher

If anyone has a plastic DRIVE SPROCKET COVER for the left side,

Please PM me, with a price....

When my chain exploded this week, it busted mine up...
Luckily, i was only going 3mph when the chain locked up and wrapped around the CS sprocket...



All I need is the little plastic cover that keeps your pants from getting chewed into the drive chain..


Thanks ya'll, Ride Safe!

Valvecrusher & Tntmo

Front sprocket cover is on ebay.

http://www.ebay.com/itm/Honda-NX250-...ad679e&vxp=mtr

[valvecrusher]

Originally Posted by hondascoot

Valvecrusher & Tntmo

Front sprocket cover is on ebay.

THANK YOU!
I miss riding my NX.

TNTmo, if you WANT this, PM me...i don't want to bid ya up

Originally Posted by Orkodelamuerte

Another thing that I noticed is that when that happens or is about to happen (the spark issue) the tach will go crazy, showing 3k revs when Im pretty sure I'm going 1.5k.. but dont know if related...

My final thought was that my CDI is bad... what do u say?

That mostly reflects a CDI issue, and since you are getting the 'no spark'...it's almost certainly the CDI..


The issue described early in the thread, showing the 'tach jumping'...
it's NOT the tach jumping when you turn the key from 'off' to 'on'....it's when you have it turned to 'on', and you hit the start button...

while the engine is turning over, if you have a good CDI, you will see the tach needle pulsing while the engine trys to start.
if the engine is turning over, but the tach needle remains motionless...the CDI is BAD...

Simply turning the keyswitch from 'off' to 'on' will make the tach jump(usually), even if the CDI is bad..





The CDI test isn't simply turning the keyswitch, it is more 'monitoring the tach' while trying to start the engine..

[valvecrusher]

that being said,


it's odd that you say....'it's fine until the fan comes on'.....

in my experience, the Fan only runs during 90F days, sitting in traffic....95% of the time, simply riding keeps the engine cool enough that the fan DOES NOT RUN.

IF the fan running causes the engine to stall....(check wiring for a cross, or grounded wires, something crossed from fan control to engine ground?)



change the thermoswitch for the fan control....

[tntmo]

Originally Posted by valvecrusher

THANK YOU!
I miss riding my NX.

TNTmo, if you WANT this, PM me...i don't want to bid ya up

Go for it. I found a young lady who is interested in my NX, so it will probably be sold soon. I have a spare engine, seat, CDi and a few other parts that will be listed if it sells.

[Orkodelamuerte]

Originally Posted by valvecrusher

That mostly reflects a CDI issue, and since you are getting the 'no spark'...it's almost certainly the CDI..

The issue described early in the thread, showing the 'tach jumping'...
it's NOT the tach jumping when you turn the key from 'off' to 'on'....it's when you have it turned to 'on', and you hit the start button...

while the engine is turning over, if you have a good CDI, you will see the tach needle pulsing while the engine trys to start.
if the engine is turning over, but the tach needle remains motionless...the CDI is BAD...

Simply turning the keyswitch from 'off' to 'on' will make the tach jump(usually), even if the CDI is bad..

The CDI test isn't simply turning the keyswitch, it is more 'monitoring the tach' while trying to start the engine..

Haha... ok, I´ll try that one, Thanks for the explanations... sounds logical now...

Originally Posted by valvecrusher

that being said,

it's odd that you say....'it's fine until the fan comes on'.....

in my experience, the Fan only runs during 90F days, sitting in traffic....95% of the time, simply riding keeps the engine cool enough that the fan DOES NOT RUN.

IF the fan running causes the engine to stall....(check wiring for a cross, or grounded wires, something crossed from fan control to engine ground?)



change the thermoswitch for the fan control....

Thanks for your concern... This is exactly what happened:

After having the whole engine rebuilt; I noticed that the fan was kicking in; and even though I WAS sitting in traffic, it was a surprise to me since I saw it in action only once since i bought the bike. Moreover, it kicked in like 2 or 3 times in a 10 mile city ride. Also, in that hot condition; the no-spark-condition began. Ever since, I would not be able to go over 5k revs for a long period; since when gaining heat, the no-spark bastard would kick in...

Ever since I changed the spark plug for the OEM one, the heat condition disappeared completely, and the fan is back to sleep. I can feel it in my legs too .. (that happened 2 days ago..). Apparently, the OEM plug has a higher resistance so it dissipates the heat more efficiently. Still, the no-spark thing remains.

I´ve just bought a new Ignition Coil, and I borrowed a working CDI from my mechanic, so as soon as I get off from work I´ll see what happens...

PD: How that small-bike-spark-plug ended up in my bike will always be a mistery..

[IheartmyNx]

TN, VC, if either of you hasn't got one yet PM me...

Mine is just sitting taking up space until I can build it (my parts bike)...

Either one of you, or any ADV member needs it just PM... I'll stick it in a box send it to ya...
I don't need any all-seeing-eye for it.

One will come back around when the time for it comes.