[Subbu-500]

Hello guys,
It has been some time since i last posted anything on the site. Mostly coz my 2014 Standard 500 (Carb) has been running well. The odo stands at a little over 7k kms and for the last month or so i hear the engine knocking sound every time i slow down and accelerate (moderately hard) . Don't know if this is a serious issue as the bike is just over 7 months old. I am pretty sure it is the knocking sound. The worst part is that it happens in all the gears except 1st. I have very little knowledge about this. I guess knocking usually happens when an engine is reved hard under load and in a higher than idea gear. Please educate me of any other reasons this can happen! It is kind of disappointing for a 500 cc motor . Will upgrading the spark plug to NKG or the likes help here?

[Vince]

     There is a decompress mechanism built into the exhaust cam of the unit engine to ease starting. A lot of them rattle or knock at low RPM. That is probably all it is. Check with your dealer to be sure.

[Arizoni]

Subbu:
Perhaps you already know this but the new UCE engine doesn't like to run very slowly like the old Royal Enfield engines did.

It is really happiest when running faster than 2500 rpm and trying to accelerate with the engine running slower than that can result in pinging (pinking) or knocking noises.  I suspect this is the cause of the sound you notice.

Changing the spark plug will have no effect on this but trying a higher octane fuel might help.

[Subbu-500]

Thank you for the inputs guys! I guess i will just accept it one of many things that are inherent to the UCE. But i am pretty sure it has happened even when i am at good speeds (> 60kmph) in fifth and drop down to fourth and accelerate bit hard to complete a quick overtaking. But may be i just need to change my riding style a bit for some time and observe. I will report back with my findings...thanks again.

[ace.cafe]

Thank you for the inputs guys! I guess i will just accept it one of many things that are inherent to the UCE. But i am pretty sure it has happened even when i am at good speeds (> 60kmph) in fifth and drop down to fourth and accelerate bit hard to complete a quick overtaking. But may be i just need to change my riding style a bit for some time and observe. I will report back with my findings...thanks again.

If it's pinging, try a higher octane grade of fuel.

[Subbu-500]

Hi Ace, could you tell me what is the difference between "knocking" and "pinging"  ?

[ace.cafe]

Hi Ace, could you tell me what is the difference between "knocking" and "pinging"  ?

Some people use the terms interchangeably.
However, I like to try to differentiate a "ping" from a "knock", in that pinging is combustion related, and knocking could be a mechanical issue like bearing failure.

Pinging sounds like erratic rattling with a high pitched metallic sound. almost random frequency that increases as you open the throttle. It almost never happens when decelerating. Sort of like keys rattling around on a metal plate.

Knocking, in my world, is a hard pounding sound of two metal parts hitting each other, and it will increase or decrease with accel or decel, usually. Like a hammer on an anvil. This is normally indicative of an impending parts failure.

So, that's how I view these terms, and I try to get novices to identify these sounds more conclusively in order to better guess at the cause over the internet.

Probably at the low mileage of your bike, it would not likely be a serious issue, but pinging can cause parts failures if it is not remedied.
With pinging, if you put in a tank of higher octane fuel, it will cure it. If it does, you must have the ignition timing checked, or use the better quality fuel on an every day basis.

[Subbu-500]

 ...i am not sure i understand that to an extent that i can show off in front of another novice like me  but i will get a tank of higher octane fuel when i run out of the last refill (which was yesterday unfortunately) and hope the pinging or knocking goes away and will have the ignition timing also checked.

Thanks a ton

[Ducati Scotty]

Pinging sounds more like a rattly tin can.  Knocking sounds like a much more substantial clunking noise coming from the engine.

If you can take a cell phone video with sound and post it, that might help quite a bit.

Scott

[ace.cafe]

I just looked and saw you are in India.
Chances are very good that the fuel you have in your tank is crap.
Try to find a place that has good fuel.

[Subbu-500]

Scott, yes the sound is just like you have described and i am sure it is from the engine too. I will try to record the sound if i can find someone to ride pillion so that i don't have to perform stunts while riding.

Ace, i always tank up at the same gas station i have been going to for as long as i can remember and have had not issues with any of my cars of bikes thus far..so not sure if fuel quality is that bad. I guess the fuel quality in India is generally inferior compared to some first world nations & i would think that RE was well aware of this when they were designing the engines as most of them were going to be doing duty with in the country. May be i just need to change my riding style keeping in mind that i don't have an iron barrel that could chug along at 30 kph in 3rd all day long without breaking into a sweat.

[SteveThackery]

However, I like to try to differentiate a "ping" from a "knock", in that pinging is combustion related.....

And just to confuse matters further, here in the UK we mostly refer to "pinging" as "pinking".  And as Ace says, "pinking" is only used to describe the sound made by detonation or pre-ignition; mechanical stuff is usually called "rattling" or "knocking" or "It's shagged, mate".

[suitcasejefferson]

I always described "pinging" as sounding like marbles being shaken in a glass jar.  Knocking is a lot lower in frequency, usually slower and more steady. Knocking is more likely to vary with the sound of the engine. All engines ping when you put a load on them in too high a gear  (lugging) It is caused by detonation, or the air/fuel mixture igniting in the cylinder before the spark plug fires.

[SteveThackery]

It is caused by detonation, or the air/fuel mixture igniting in the cylinder before the spark plug fires.

Just to be an insufferable, nitpicking bastard, what you've described is pre-ignition.  Detonation occurs after the spark plug fires.

I also realise that your sentence could be read either way, which makes me an insufferable, nit-picking bastard who talks too much.   

[ace.cafe]

I think it is probably just bad gasoline.