RX-3 Spark Plug

[2LZ]

Originally Posted by rtking

I am indeed running the NGK Iridium CR7EIX that Azhule quoted. Unlike the old Vino 125 I had where the Iridium spark plug made a noticeable difference, the RX3 doesn't really feel any different. But knowing the quality of the spark plug and hotter spark is worth the price of the plug if nothing else IMO.

Indeed. Once you install one, you can pretty much forget about it.

Of course, living where I do, do you think ANY auto parts store in town would have one? Oh no....
Back to Amazon....and then obviously I had to play the "free shipping on any order over 49.00" game (hooked on free shipping)....and it's just far too easy to find 41.00 more dollars worth of stuff I didn't need to buy... ;-)
Hook, line and sinker, I tell ya.

[BlackBike]

Originally Posted by 2LZ

Indeed. Once you install one, you can pretty much forget about it.

Of course, living where I do, do you think ANY auto parts store in town would have one? Oh no....
Back to Amazon....and then obviously I had to play the "free shipping on any order over 49.00" game (hooked on free shipping)....and it's just far too easy to find 41.00 more dollars worth of stuff I didn't need to buy... ;-)
Hook, line and sinker, I tell ya.

Yep, I had that urge with Amazon fulfillment too but I am now going to other sellers for free shipping with good results and also no tax which amazon seem to sales tax everything now it seems. Also liking ebay more too since can pay with regular credit card.

[ElectricCircus]

Just four your information:

The spark plug that came with my RX3 2016 carbureted version is the DENSO U24ESR-NB, 0,7mm gap:

[Inroads]

^^^ that spark plug is one step colder than the North American RX3.

Carburetor and the OCS are the only differences ?

Wonder why we run a hotter plug ?

It's the OCS and thermostat ?

[ElectricCircus]

After looking at the comments here I´ve replaced the OEM DENSO U24ESR-NB with a NGK CR7EIX gapped at 0,75mm.

I´ll see how it performs.

[Inroads]

^^^ be careful running that hotter plug wide open at low altitudes.

Get a good plug reading on an extended high speed run.

I would stay with the 24 (8) unless you saw a dark(cold) plug.

You always wanna stay with factory recommendations unless you have sufficient

Evidence of running too "hot" or "cold"

[Jay In Milpitas]

This may help some folks:
http://densoautoparts.com/spark-plug-part-numbering

[ElectricCircus]

Originally Posted by Inroads

^^^ be careful running that hotter plug wide open at low altitudes.

Get a good plug reading on an extended high speed run.

I´ll be watching that.

[bogieboy]

Originally Posted by Inroads

^^^ that spark plug is one step colder than the North American RX3.

Carburetor and the OCS are the only differences ?

Wonder why we run a hotter plug ?

It's the OCS and thermostat ?

my guess is US emmisions... and nothing more than that....

[AdventureDad]

Originally Posted by Inroads

^^^ be careful running that hotter plug wide open at low altitudes.

Get a good plug reading on an extended high speed run.

I would stay with the 24 (8) unless you saw a dark(cold) plug.

You always wanna stay with factory recommendations unless you have sufficient

Evidence of running too "hot" or "cold"

Why? I live at sea level in a very humid environment (if that matters, other than very dense, moist air) Every run on this bike is wide open throttle, that doesn't always equate to "high speed". I'm not sure what plug came in my US version bike, probably the same as all the other FI models sold here. Could it be an issue?

[Inroads]

Originally Posted by AdventureDad

Why? I live at sea level in a very humid environment (if that matters, other than very dense, moist air) Every run on this bike is wide open throttle, that doesn't always equate to "high speed". I'm not sure what plug came in my US version bike, probably the same as all the other FI models sold here. Could it be an issue?

If you ran a 1 step hotter plug than recommended the worse case scenario

Would be wide open at sea level (as lean as you would get)

The only reason to stray from factory recommended heat range would be:

If you just road around town and at slow speeds you might go 1 step hotter.

Or running long distance wide open then go with 1 step colder range.

Many Jap bikes will recommend just that in their manuals."For continuous high speed running"

Strangely Zongshen(at least in North America)runs a 7 heat range when jap road

Bikes run 8's. (NGK heat range reference numbers). NGK 7 and 8= ND 22 and 24

It is safe to say that heat range selection is not as critical with FI compared to carbs.

If you select a too cold a plug no big deal but it is a big deal if you select too hot a plug.

[bogieboy]

Originally Posted by Inroads

If you ran a 1 step hotter plug than recommended the worse case scenario

Would be wide open at sea level (as lean as you would get)

The only reason to stray from factory recommended heat range would be:

If you just road around town and at slow speeds you might go 1 step hotter.

Or running long distance wide open then go with 1 step colder range.

Many Jap bikes will recommend just that in their manuals."For continuous high speed running"

Strangely Zongshen(at least in North America)runs a 7 heat range when jap road

Bikes run 8's. (NGK heat range reference numbers). NGK 7 and 8= ND 22 and 24

It is safe to say that heat range selection is not as critical with FI compared to carbs.

If you select a too cold a plug no big deal but it is a big deal if you select too hot a plug.

not trying to argue, but a step too cold can cause knocking and incomplete burn, a step to hot, preignition... neither a good thing... IF zong uses a knock sensor on ther FI models, it may retard the timing to avert the issues both way, but i dont know if they do... wouldnt want to find out the hard way....

[AdventureDad]

Sooooo....maybe Im not quite understanding....should I stay eith the stock plug? (I do understand the cold vs hot plugs and their uses) just not what we should do with our particular bikes.

[Inroads]

Originally Posted by bogieboy

not trying to argue, but a step too cold can cause knocking and incomplete burn, a step to hot, preignition... neither a good thing... IF zong uses a knock sensor on ther FI models, it may retard the timing to avert the issues both way, but i dont know if they do... wouldnt want to find out the hard way....

One step too cold a plug will not cause knocking.The worse thing over time would be a fouled plug and carbon buildup.

You would have to have a fair amount of carbon to create a hot spot/knock.
Not gonna happen with one step colder.

There are no knock sensors/retard on these bikes.

[Inroads]

Originally Posted by AdventureDad

Sooooo....maybe Im not quite understanding....should I stay eith the stock plug? (I do understand the cold vs hot plugs and their uses) just not what we should do with our particular bikes.

You should stay with the Zongshen recommendation plug.

I would possibly consider 1 step colder on extended high speed long distance runs.
It wouldn't hurt.
In addition you should be reading your plug.