Valve ping at hot idle, r.p.m variation at idle, engine mapping

[RMac]

Great. A techy section. That made me register Start this off by asking about things I am wondering about...

#1: Pinging? Noted a sound that may indicate some valve pinging when bike is warmed up at idle. I note a subtle rythmic popping sound from the engine case that is not present at cold start. Not at all sure, but looking for your own experiences and thoughts?

#2: R.p.m. variation at idle. On cold start the idle r.p.m becomes a bit unstable (fluctuates by up to +/-200r.p.m as the fast idle settles to normal idle r.p.m.). Once stabilised at normal r.p.m there is still some small fluctuation at idle (not more than +/-50r.p.m). This is present all the time, even after stopping after a long stretch of riding. Spoke to Yamaha dealer and he said that some degree of idle variation is normal for all large bore twins. Thoughts?

#3: Engine mapping. As we are all probably aware of now the S10 exhibits a flat spot between 4k and 5k rpm. For one up riding I don't find this much of an issue (a dip followed by a kick at 6k rpm), but when two-up I have noted that the bike seems to quite dramatically run out of steam in this flat region above 4k rpm. This is in S-mode. This is not so much a question, but just to start a point for discussion.


#4: Bonus question How to do wheelies on this bike? Presumably TCS mode OFF for starters, but beyond that what's the technique? I know, if I am asking this question I shouldn't be considering attempting it, but just curious Now, no-one will take my post seriously....

 

[MortiisMachine]

Hi, for point 4 try here for some info

http://www.yamahasupertenere.com/index.php?topic=128.0

 

[HoebSTer]

Rmac, make a note of this if it sounds like a ticking. When i owned my VSTROM, at the 600 mile mark I heard a ticking and mentioned it to dealer that something was wrong, or too loud. His reply was "oh, it's just the modern technology, there is alot of stuff going on in this engine and it's just normal!" I said ok, thought to myself (sarcastically) i am an idiot!!! Well fast forward to 13k miles and checking my valves myself. The front exhaust valve was .18mm past the highest allowable limit. It should of been .30 max, it was .48mm. Well, it looks like the idiot mechanic didn't know his ass from a hole in the ground. He left that dealer, then about 2 years later at another tire repair place, i see it is the same goof-ball working out in the shop and mentioned to the dealer manager how he handled that past situation.

 

[RMac]

Rmac, make a note of this if it sounds like a ticking. When i owned my VSTROM, at the 600 mile mark I heard a ticking and mentioned it to dealer that something was wrong, or too loud. His reply was "oh, it's just the modern technology, there is alot of stuff going on in this engine and it's just normal!" I said ok, thought to myself (sarcastically) i am an idiot!!! Well fast forward to 13k miles and checking my valves myself. The front exhaust valve was .18mm past the highest allowable limit. It should of been .30 max, it was .48mm. Well, it looks like the idiot mechanic didn't know his ass from a hole in the ground. He left that dealer, then about 2 years later at another tire repair place, i see it is the same goof-ball working out in the shop and mentioned to the dealer manager how he handled that past situation.

This is a problem with being forced to rely on workshops. I did all my service including valve adjustment on my DL650. Now I am obliged to let a Yamaha authorised workshop do all the service to maintain my five year warranty. They are very strict on that point in Sweden. During my 1000km oil change the mech managed to scratch the exhaust pipe when re-fitting the engine bash plate. You pay them to do the work without any damage to the bike!

At-least in your case you found the valves to be loose. That's nowhere near as bad as when they are tight.

When I go home this weekend I will start her up and try to better define the "popping" sound that I am talking about. I have not run the engine for a week and cannot say for sure that I am accurately describing it. It does not sound like valve ticking, I don't think...Valve ticking in itself is something I consider to be normal.

 

[rocca]

RMac, if you can make a good sound recording and post to it, or link to it, that would perhaps help those of us who have the bike to comment on whether there's anything different to be heard.

Regarding idle fluctuation, I don't think that what you describe is out of the ordinary. My bike does roughly the same, as have a series of twins (and fours) that I've owned in recent years.

I have to say that I haven't really noticed a flat spot at 4-5k. I've only ridden the bike solo, so far...

 

[Swagger]

No flat spots with mine. Good delivery throught he power range. Can sound a bit rough .... put that down to the firing order.

 

[Koinz]

Not having an ST (yet), I can only speak in generalities - #2 and #3 are typical for late model fuel injected bikes. Manufacturers run these things very lean, and that results in some idle fluctuations as the engines are constantly adjusting their fuel/air mixture. It may smoothen out as engine breaks in. You might want to check the Throttle sync (if it's required on the Tenere).
One thing I have noticed on other bikes is that any small vacuum leak will cause the system to over-compensate and give you the same symptoms.

I love the fact that the ST has these different fuel map modes and I can't wait to feel the difference between them.

Question to you current ST Owners - Does the Tenere have an O2 sensor? (Oxygen sensor).

 

[Uncle]

Flat spot between 4k and 5k rpm ???................... No, mine is pulling from start to redline like a steam train

 

[Swagger]

.... Question to you current ST Owners - Does the Tenere have an O2 sensor? (Oxygen sensor).

Sure does! Low offside .... that's on the right to the unwashed
BTW the mapping is a neat and meaningful development on this bike. I ride mine predominantly in sport mode with the traction control off. Happy days!!!! ;D

 

[3putt]

I suspect since it is TBW there is only one map just like the MTS12.

 

[RMac]

Interesting to hear that no-one who has answered yet is noticing a flat spot between 4k to 5k. I have seen published dyno charts for the ST that clearly show a torque dip in this region. Putting 2+2 together has made me assume that it is common to all ST's. The ST is also apparently power restricted in gears 1 through to 4. I was about to blame EU noise emission regulations for the 4-5k dip, but Swagger in the UK is reporting no flat spot. Very interesting. Maybe, I have a very sensitive, butt dyno. I am coming from a DL650 which had extremely linear power delivery and no idle r.p.m. variation whatsoever.

 

[hANNAbONE]

#1: Pinging? Noted a sound that may indicate some valve pinging when bike is warmed up at idle. I note a subtle rythmic popping sound from the engine case that is not present at cold start. Not at all sure, but looking for your own experiences and thoughts?

perhaps you should review the type of fuel you are using, move it to a higher grade ??

...put in a can of SeaFoam or Techron (*Chevron product*) or the like and see if it goes away.

 

[RMac]

#1: Pinging? Noted a sound that may indicate some valve pinging when bike is warmed up at idle. I note a subtle rythmic popping sound from the engine case that is not present at cold start. Not at all sure, but looking for your own experiences and thoughts?

perhaps you should review the type of fuel you are using, move it to a higher grade ??

...put in a can of SeaFoam or Techron (*Chevron product*) or the like and see if it goes away.

Having had a chance to listen to the motor again last weekend I can say for definite that the sound only appears when engine has warmed up. In addition, I would now describe as a "knocking" rather than "popping". I don't think it is valve clatter as I hear the valve clatter from cold start and has a different sound. In Europe fuel on offer is 95 or 98 octane which I think is equivalent to 91/93 octane in the U.S. For sure, I can try 98 octane when I get the bike back on the road next season to see if that helps. Thanks.

 

[Uncle]

Mine is running on 95 octane without any problems ..................

 

[markjenn]

I doubt the problem is pinging which tends to be a hot/heavy-load issue, not an idling issue.

And BTW, any thread on pinging brings up octane numbers which in turn gets confusing because of the different octane-rating systems used worldwide. Europe (and probably Africa) uses the Research Octane Number (RON), whereas North America uses the AKI (Anti-Knock Index) which is the average of the RON and the Motor Octane Number (MON). The MON tends to be about 8-10 pts lower than the RON, so net, North America AKI octane numbers on the pump tend to be about 4-5 points lower than Europe. I believe Yamaha is recommending 95 RON or higher for the S10, which is probably 90-91 AKI US - typically premium but sometimes mid-grade at some locales.

- Mark

 

[RMac]

Got to also remember that this sound I am hearing may be and most likely is perfectly normal. It just drew my attention, so I decided to ask about it here. Hard to make a good quality recording without compression artifacts to "share the sound". My DL650 also changed sound quite a lot as it warmed up. Everyone talked about the "DL650 knock" at running temperature, but no-one ever had any real mechanical issues with it.

If it is still concerning me next season, I'll take it to the dealer and let them check it out...Fully expecting them to say that it is normal (whether it is or not..)

Thanks for the advice.

 

[caveman]

Mine exhibits the same noise as does the others I ride with but cant find any flat spot to speak of.
Power delivery is smooth thru the rev range.

 

[Swagger]

.... Interesting to hear that no-one who has answered yet is noticing a flat spot between 4k to 5k. I have seen published dyno charts for the ST that clearly show a torque dip in this region ....

We have come to the conclusion that this dip/flattening is for European homologation requirements. I don't notice it on my bike but then it has been heavily breathed upon.

Look at the curves on the Akrapovic link they show a dip in the range. Spoke of this to another owner and he too had never really felt it.

 

[MortiisMachine]

.... Interesting to hear that no-one who has answered yet is noticing a flat spot between 4k to 5k. I have seen published dyno charts for the ST that clearly show a torque dip in this region ....

We have come to the conclusion that this dip/flattening is for European homologation requirements. I don't notice it on my bike but then it has been heavily breathed upon.

Look at the curves on the Akrapovic link they show a dip in the range. Spoke of this to another owner and he too had never really felt it.

Can't say I noticed any issues when I test rode one.

 

[RMac]

There is one review I found that makes reference to a "slight dip" at 4.5k. This is the only reference I can find specifically addressing this.

http://www.xtz750.com/index.php/super-tenere-owners-forum/viewtopic.php?f=52&t=4031

Caveman, were you referring specifically to a slightly irregular knocking/tapping sound that appears when the engine is hot (> roughly 85 deg) but not audible when cold? Reassuring if others notice the same sound.