Engine ticking noise, mainly on acceleration?

[Guest SpinyBiker]

Hi guys,

Bought a second hand Nc750S DCt from a Honda dealer a month or so ago. 3k miles on the clock in very good condition bike not yet 18 months old.

I have noticed though there is a loud ticking noise mainly when I open the throttle. Thought perhaps that was z characteristic of the bike but what worried me last night was when stopped at one set of traffic lights I could feel the tick through the handlebars.

When riding the sound does seem like it's coming from towards the front of the bike.

Any ideas? It's still under warranty but sort of don't trust the dealer who will probably just tell me there's nothing wrong.

Thanks Spiny.

[Tex 36,817]

Try a different dealer. I don't much like the sound of it and that's what warranties are for..

[DaveM59 1,603]

Have a look at it in the dark, rev it on the centre stand and look under the front at the plug leads. These bikes do have a weakness in decaying plug caps and it can be seen at night as sparks visibly arcing to the cylinder head from under the caps. Unless it's got widely adjusted valve clearances or a loose timing chain which unless faulty from new seems unlikely, but so is any fault at this mileage. Then again why did the original owner chop it in after so short a duration?

As Simon says, if you have warranty use it and it doesn't have to be with the dealer you bought it from, any Honda dealer will honour it.

[embee 7,288]

Could be all sorts of things, trying to diagnose these things remotely is almost impossible.

 

If it is definitely dependent on load it's not beyond the bounds of possibility for it to be a simple as a loose spark plug leaking gas ........................... or it could be a lot more sinister. There have been a couple of reports of broken timing chain tensioners apparently, but very few and far between and certainly not a regular issue, and you wouldn't expect any noise from that to be load dependent..

[trisaki 2,029]

Plug lead as mentioned or a slightly leaking exhaust or normal engine noise coz they aren't the quietest of engines especially if you are used to a super quite modern engine

[embee 7,288]

That's a good point from Mark, check the exhaust manifold joint for leaks, that would definitely be load dependant and it's a very simple one to diagnose and/or fix.

[Puglim 61]

Hi guys,

Bought a second hand Nc750S DCt from a Honda dealer a month or so ago. 3k miles on the clock in very good condition bike not yet 18 months old.

I have noticed though there is a loud ticking noise mainly when I open the throttle. Thought perhaps that was z characteristic of the bike but what worried me last night was when stopped at one set of traffic lights I could feel the tick through the handlebars.

When riding the sound does seem like it's coming from towards the front of the bike.

Any ideas? It's still under warranty but sort of don't trust the dealer who will probably just tell me there's nothing wrong.

Thanks Spiny.

Hi Spiny,

Whilst not on my nc700 I have experience a very similar ticking noise on a vehicle. It turned out to be the exhaust manifold with the tiniest amount of a gap. A new gasket cured it. This could be the problem on your 750s. As most have said though go down the warranty route , it is Hondas problem. Good luck.

Alan

[Guest SpinyBiker]

Cheers guys some good pointers for me to check. I think the exhaust is ruled out as it did this before I recently changed the exhaust and still doing on the new after!market exhaust. All fittings etc were checked and double checked when I did the exhaust.

Plugs - will check but not sure that would cause me to feel the 'tick' through the handlebars at a standstill?

Other than that chain tensioner is in back of my mind but wouldn't have a clue myself how to check that out so would be a dealer referral.

Cheers.

[bazza 3,629]

Have a look at it in the dark, rev it on the centre stand and look under the front at the plug leads. These bikes do have a weakness in decaying plug caps and it can be seen at night as sparks visibly arcing to the cylinder head from under the caps. Unless it's got widely adjusted valve clearances or a loose timing chain which unless faulty from new seems unlikely, but so is any fault at this mileage. Then again why did the original owner chop it in after so short a duration?

As Simon says, if you have warranty use it and it doesn't have to be with the dealer you bought it from, any Honda dealer will honour it.

Dave's  right-why not check the log book and contact the first owner -maybe he can tell you something useful!

[snotkop 4]

It may also be the engine pre-ignition ( pinging ). I have noticed this more so in hot weather. I think to achieve the amazing fuel consumption Honda have tweaked everything to run on the edge hence the well advanced ingnition timing.

[DaveM59 1,603]

Any conclusion to this issue? Nice to know for future reference.

[Guest SpinyBiker]

No resolution. The dealer had a look at it today whilst it was in having a fork dust seal replaced. They took it out but just referred to the the bike going into 5th at 30ph as a DCT and so the engine is straining. I explained that was not what I was referring to, but you only really hear it if you know what your listening for. I hear it most when going along a flat road, c33mph with very gentle throttle I.e. to maintain that speed, then you hear the loud ticking, which sounds in time with the engine turning over. I've just to keep an eye/ear on it. The bike will go back in later in the summer for pr4's fitting so if it persists or gets worse will mention again.

Cheers everyone for you suggestions which I've worked through.

[Guest Meireles]

Hi,

I bought a new NC750x last month, and I am hearing the same noise as you mentioned in your post!

my bike has only 1000 km and made last week your first revision service!

Only during a little acceleration, like a valve “knocking”  during the initial engine load period, mainly in lowers engine revolutions! Between 2000 and 3000 RPM.

Please, arrived you in some solutions for your problem?

I live in Brasil and have the same problem with the Honda dealers!

for him... the noise is always “normal”.....

But others NC’s I compared have not this noise during engine

if someone have the same problem, and got the solution or understood the origin, please help me!

thanks

Meireles

 

Edited June 17, 2019 by Meireles

[Griff 1,556]

This noise may be coming from the air box intake close to the steering stem. There is a noise on all the NC motors under initial acceleration. Its like a metallic whistling or even ticking. My former NC700X did it and my current X-Adv also does it. As such if it is the same sound it is normal.  

[Guest Meireles]

Dear Griff,

the sound I mentioned is a metallic knocking like an hard and loudly “tec tec tec” only during inicial acceleration with the motocicleta in low speed  ( gear engaged and low engine).

it happens under engine initial loud.

It seems the same noise related by SpinyBiker !

I ride two others NC750X and this noise is extremely low, if compared with my bike!

m

My bike has only 900 km.

Honda dealer mechanic said me that is not a problem ...but... only with my bike this noise happens... and is normal???

[DaveM59 1,603]

Sounds like the engine gremlin knocking on the crankcase to tell you to stop being so soft during the running in period and start screwing the nuts off it a bit and bed things in properly. 

[SteveThackery 3,090]

9 hours ago, Meireles said:

Dear Griff,

the sound I mentioned is a metallic knocking like an hard and loudly “tec tec tec” only during inicial acceleration with the motocicleta in low speed  ( gear engaged and low engine).

it happens under engine initial loud............

 

Honda dealer mechanic said me that is not a problem ...but... only with my bike this noise happens... and is normal???

 

This sounds very much like "pinking" (low speed detonation).  My NC never did it, and I would say no, it's not normal.

[Tex 36,817]

14 minutes ago, SteveThackery said:

 

This sounds very much like "pinking" (low speed detonation).  My NC never did it, and I would say no, it's not normal.

 

I agree. Try running it on a higher grade of petrol (if available where you live?) and see if it changes. 

[Grumpy old man 4,673]

21 hours ago, SteveThackery said:

 

This sounds very much like "pinking" (low speed detonation).  My NC never did it, and I would say no, it's not normal.

Pinking, that's something I've not heard or heard anyone mention for a long time. 

[Tex 36,817]

2 hours ago, Grumpy old man said:

Pinking, that's something I've not heard or heard anyone mention for a long time. 

 

Because modern engines have ‘knock sensors’ which detect signs of detonation and, instantly, adjust the timing to suit. But nothing is infallible and they can only do so much. I don’t know where the OP lives (I suspect it’s not the U.K.) and if the petrol is poor quality it might defeat the sensor’s ability to control it. I would suggest avoiding large throttle openings at low revs. 

[SteveThackery 3,090]

34 minutes ago, Tex said:

 

Because modern engines have ‘knock sensors’ which detect signs of detonation and, instantly, adjust the timing to suit. But nothing is infallible and they can only do so much. I don’t know where the OP lives (I suspect it’s not the U.K.) and if the petrol is poor quality it might defeat the sensor’s ability to control it. I would suggest avoiding large throttle openings at low revs. 

 

That's interesting - I didn't know the NC had a knock sensor.

 

Anyway, it does sound like low speed detonation from the description.

[ManosCR 2]

And in my bike I hear this sound also at a calm acceleration of 1800-2300 revs (when the engine is cold, the noise is hardly heard.). It started when I had 3000 km and continues until now without the noise getting stronger. Without having much experience on this engine, I think it's the sound coming from the valves without meaning that they need regulation. They are still within the allowable limits and i just wait for the 24,000 km big service. So in my opinion, there is no reason for worry.

[SteveThackery 3,090]

1 hour ago, ManosCR said:

And in my bike I hear this sound also at a calm acceleration of 1800-2300 revs (when the engine is cold, the noise is hardly heard.). It started when I had 3000 km and continues until now without the noise getting stronger. Without having much experience on this engine, I think it's the sound coming from the valves without meaning that they need regulation. They are still within the allowable limits and i just wait for the 24,000 km big service. So in my opinion, there is no reason for worry.

 

The truth is clear: we are all struggling because it's almost impossible to diagnose noises via written text!

 

It could be anything, or it could be nothing.  I recommend the OP rides another NC to see if he can hear the noise on that one.  I also recommend another owner riding the OP's bike for a second opinion.  If the dealer really won't play ball, then go to another for their opinion.

 

I don't think it's wise to ignore noises unless you've done at least some investigation and satisfied yourself that it's OK.

[Tex 36,817]

7 hours ago, SteveThackery said:

 

That's interesting - I didn't know the NC had a knock sensor.

 

Well, if I am brutally honest I don’t know for sure that it does. But with it’s ‘half a Jazz’ heritage I would be amazed if it didn’t.. 

 

7 hours ago, SteveThackery said:

Anyway, it does sound like low speed detonation from the description.

 

To me too. But the NC is a (disappointingly) noisy old lump, so it could be anything. 

[fred_jb 10,264]

I always thought mine sounded like a coffee grinder when trundling along at a steady speed on a neutral throttle. 🙂