Gotta ask, what exactly is the point of doing that? What's it get you, and why isn't this just so much engine abuse? It sure doesn't have anything to do with normal riding.

Any engine operation much above idle needs to be with the transmission in gear, with the engine providing power to the rear wheel. I can't imagine any engine map that takes unloaded high engine RPM into account.

 

Gotta ask, what exactly is the point of doing that? What's it get you, and why isn't this just so much engine abuse? It sure doesn't have anything to do with normal riding.

Like they already explained, it allows you to rev match downshifts. Blipping the throttle is part of riding, and there is no excuse for the 900HT engine's behavior in this regard.
@crjwingman This issue is already being discussed here:

http://www.triumphrat.net/water-coo...ns-technical-talk/832897-ping-slap-cough-on-quick-throttle-blip-under-load.html

 

My Thruxton does the same thing. It only does it if say I'm coasting downhill in neutral and rev match to shift into gear. Never noticed it except when the bike was going from neutral up or down a gear. I don't think it's an engine knock as when it happens the rev is delayed, the "ting" noise occurs and then the engine revs up.
I've had the Thruxton actually knock on regular gas, but it happened at high rpm while accelerating. I've since quit using regular gas unless it's my only alternative. Unless one spends a lot of time over 6k rpm, this probably won't be an issue for you.
I've also had many bikes that ping on regular gas. Mostly inlines (that spec regular gas too). That is also a tinging sound but many many of them with the bike in gear and the throttle being applied hard under load.
This little ting thing has me baffled too, but I'll bet it's an electric relay clicking under a metallic cover.
Don't coast around in neutral and I bet you stop noticing it. Seeing as its happening in two totally different engines, I'd bet a tall cold one it's some electric gizmo the ECU is firing when revving the engine in neutral.

 

This little ting thing has me baffled too, but I'll bet it's an electric relay clicking under a metallic cover.
Don't coast around in neutral and I bet you stop noticing it. Seeing as its happening in two totally different engines, I'd bet a tall cold one it's some electric gizmo the ECU is firing when revving the engine in neutral.

If that were the case, it would be easy to reproduce. It isn't. It is pretty random, but always happens under the same conditions.

It also coincides with a decided miss, with a brief hesitation, so it is definitely a form of misfiring.

It only happens when you blip as fast as possible, from zero to 20% throttle near instantly. I think we all know what a blip means, it implies a flick of the wrist. The ping happens the exact moment right before the RPMs begin to climb.

Any sort of slower ramp up in throttle results in a linear RPM increase, and no ping.

The other forum member that posted a sound clip (in yet another thread about this issue) was able to reproduce it almost every time. Mine's not nearly as bad as that.

Also, I've been through three tanks of 93 octane, and the problem has not happened once since switching from 87. And I've been trying to reproduce it. That in and of itself should be hard evidence as to the cause.

 

Im experiencing the knock also but not as severe as yours seems. Going to try higher octane and see what happens. I believe knock (detonation) and pre-ignition are different but regardless in my reading high compression engines (10.5:1 and over) need higher octane. The 900HT is 10.55:1 yet the manual says regular gas. Ethanol content may also be a factor.

My father who's been riding for over 45 years has been working on bikes just as long puts nothing but high test in all his bikes including a 1976 T140.

 

re-posting the audio clip here http://vocaroo.com/i/s1PwVig4ltzM

I must add that its not as easy to reproduce the knock on my bike with the ambient temperature below 40 Celsius (104F).

 

The "little ting" noise is knocking. It's not some huge clunk, it just sounds metallic like a teaspoon tapping something metal.
@rebel1735's noise is also pre-detonation, but sounds to be happening at much lower ignition advance.
It will happen more in higher ambient air temperatures as the mixture is leaner, but it's usually caused by fuel being too low octane.

These bikes have no knock sensor, so most new vehicles are happy to use fuel with less pre-ignition inhibitors because they simply retard the ignition timing when they detect knocking, but the Triumphs don't have them.
Stick premium fuel in and it should go away. I know Triumph say it can run on economy fuel, but not all low octane fuel is equal, and some will simply cause pinging more than others.

I always use Premium. With regular fuel I get knocking if I crack the throttle open at 2Krpm, so it's up to you. If you accelerate gently and ride on a freeway lots then the economy stuff is not ideal but OK, whereas if you want decent power and no knocking you should go up on the higher octane.

 

Stick premium fuel in and it should go away.

I do and so does the OP and it still happens. Now that I heard the clip without helmet and earplugs, I agree it does sound more like a pre-ignition ping than I originally thought. It feels (and sounds thru a helmet) like the throttle is delayed, but based on the audio clip it really isn't. Odd it only happens for me in neutral though. I suppose that's because it's so low in the revs when the throttle is cracked.
One thing worth trying is switching to Rain mode and see if it still happens. Presumably, the ignition is being advanced more and more the "sportier" the map.
This is the first twin I've ever had ping at low rpm. Had some knock hard at high rpm, hard on the gas, but this is a new one to me. Even inlines that have pinged at low rpm always made lots of pingy noises and did it when pulling load hard at lower rpms. OTOH, I've never had a bike that was so clean and efficient either.

 

The bigger displacement models could be more prone to this but my 900 runs really well on standard UK fuel even when I deliberately provoke it by running really low revs and accelerating without changing down.

 

That is called "lugging" and is not good for the engine. Don't be lazy, downshift below 3,000 rpms

 

I always use 93 in motorcycles, just a habit from back in the day. Never had this problem in my ST, even tried to see if I could make it do it yesterday.

 

The OP was not talking about normal rev matching during shifts, he was talking about aggressive throttle blipping from idle, with the bike out of gear.

 

Yes it only seems to occur when coasting in neutral, then blipping to rev match before putting into gear. I have to come down hill to get to my house and I often coast for maximum silence and I pass the people walking their babies and dogs.
Just got back from a ride and did some experimentation. With the bike in Sport mode, it was easy to get the noise and the noise was loud. In Road mode, I could get the noise, but it took more tries to get it and it wasn't as pronounced. In Rain mode, I could not get it to make a pinging noise, but still often had the same delay in throttle response I felt when doing the same thing in the other modes.
Suggests that it is a pinging issue that worsens with the advance of the timing. Bike currently has 89 octane. Will bump it up to 93 on the next fill and retest.

 

The manfacturer might say blah blah but my dealer who is an ace mechanic says 91. 87 worked fine for the Rocket which was 8.7:1 but this is 10:1. Wouldn't hurt to try it.

 

I'm currently on an 18-year Bonneville t100. My bike has the same symptoms, but it's been fixed with high octane fuel. If you've been on that bike so far, is there anything wrong with the engine because of this? Or is there a way to make sure that even low octane fuel won't cause problems?