Hard acceleration CLUNK and surge at 3K in 1st gear.

[Kelvininin]

Need some help here. Today was really the first time I took the whip to my bike, I have been taking it easy through the break in period.

The specifics: 2012 Tenere 600 miles, bone stock performance wise, Altrider crash pars, and skid plate, burning only premium fuel.

The situation: flat and level road, hard acceleration around 3K in 1st gear, TCS on and off. Once I get on it I get a couple of quick knocks that are accompanied by surge, it feels like the chain is skipping a cog, but this bike doesn't have a chain.

I first noticed it taking off from a stop light, then duplicated it predictably in a parking lot.

I did a search and found another thread with a similar cluck, under similar conditions, someone suggested it was engine knock. This is unlike any engine knock I have experienced.

I checked the fasteners, steering nut, spokes, I just did the first fluid change today, nothing unusual....

Any guesses? This is really disheartening, I traded my KTM A990 for what I thought was going to be a more reliable, easier to work on scooter, I hope I am not proven wrong.

BTW. This SOB has no qualms about pulling the front wheel off the ground, scared the bageebers out of me, even on my KTM, you had to finesse the front wheel off the ground . The S10 will just do it.

 

[phplemel]

Sounds just like TCS cycling. does the TCS light flash when this happens ? It's sounds like what mine has done on occasion when I'm in get-away mode O and it's been the tires breaking loose or TCS cycling
::021::

 

[markjenn]

TCS and/or simply lugging the engine would be my vote. Big twins aren't really fond of full throttle and 3K RPM. I doubt you have anything wrong. Nature of the beast.

- Mark

 

[GrahamD]

I think it maybe techtonic plates slipping on the mantle and running into, in your case, the pacific plate.

Happens a lot with Vmax's as well.

 

[jaeger22]

Mine did the exact same thing when it was new. Scared me at first. It sounded like hard knock from a bad lower rod bearing. ??? So I just avoided WOT at low RPM. I am currently at a little over 8K miles and I haven't noticed it for a long time now. So either it quit doing it or I have been "trained" to avoid it. For sure it has gotten no worse and caused no other issues. I am about to jump on it to start for home (currently 1800 miles from home in Albuquerque) so I will play with and see if I can still make it happen. Should have lots of time to try it as I have to cover 665 miles today. :

 

[RED CAT]

Make sure TC is OFF. If it still does it, do the Clutch Switch Mod. Should help. ::001::

 

[Kelvininin]

I fooled around with the TCS. It does it both when the TCS is on, setting 1 or 2, doesn't matter, and when the TCS is OFF.

I guess I will just keep and eye on it for now, has me thinking about buying the extended YES just in case.

What has me most concerned about this, since its coming out of break in, I discovered it riding how I would normally ride.

IF this is a motor knock, it can probably be addressed with the adjustments to the mapping and bypass air screw.

 

[Obrianmcc]

I fooled around with the TCS. It does it both when the TCS is on, setting 1 or 2, doesn't matter, and when the TCS is OFF.

I didn't quite get that.... did you try with TCS on or off?

::013::

 

[thfraser]

I'll have to see if I can repeat this on mine. I have almost 19k miles on the clock, I'll let you know what I find out.

 

[snakebitten]

Sounds exactly like big throttle with TCS 1 or 2 off-road. (I do it DAILY. I know that sound) ::013::

But he states it does it with TCS off too. So, hmmmmmmm. I can't explain that. Gotta be something else.


By the way, you become so familiar with traction limits of the rear tire that you learn to modulate your throttle to not BANG into and past TC. Instead, you just nudge up to it. Far less abrupt cut-off of power. And far less scary sounds.

 

[yz454]

We call it a heat knock,heat and fuel in the cat .

 

[Kelvininin]

We call it a heat knock,heat and fuel in the cat .

That't I'll buy.

 

[roy]

Mine does it and has since day one. Still present at 16k miles. I ignore it. Lots of throttle at low rpm brings it on and it does not seem to affect the bike and I dont hear it any other time so I
::021::

 

[Dallara]

We call it a heat knock,heat and fuel in the cat .

You're kidding, right?

Dallara



~

 

[thfraser]

Quick test would be to put on those Arrow headers and do a pre and post test...

 

[yz454]

Dallara Id try to explain more, but from past post your just to bright to under stand.And ALL YOUR EXPERIENCE.

 

[CDMartin884]

::017::

 

[Kelvininin]

Come-on now lets keep this civil.

I have experienced post combustion ignition, at a hot Cat before. It would make since. I was grabbing the throttle hard dumping a bunch of fuel. These were not roll ons. The location seemed to come from the back of the bike but I could be wrong. A lot of things going on when you quickly grab a handful of throttle.

It does seem, I am not the only one to experience this.

Would like to figure out how to fix it, without it costing too much money.

 

[snakebitten]

Actually, I have heard of catalytic converters being burdened with burning raw (excess) fuel. And it is, as I have heard, a sign of something wrong with the motor to be dumping unspent fuel to that extent into the exhaust.

So I guess technically, it could be happening to this Tenerista. But it hasn't been a widespread or reported issue with the Super Tenere. (That I have seen)

 

[Snowedin]

This knocking at about 3K revs is pretty widely documented - happens on some bikes, not on others. Most people just live with it....