Two Seconds To Return To Idle

Sounds like a sticky throttle cable mate.

 

Could be a sign they're running lean.

 

They dont have a cable.

I have a 2020....what LC stand for....

When you say takes 2 seconds.....does that mean its holding a steady rev before they start to drop down to idle speed.

 

Thats fly by wire could be the throtle sensor depends on does it hold revs for 2 minutes then drops or as said above or does it take 2 minutes to slowly drop revs

 

LC stands for Liquid Cooled.

I have a 2017 Street Twin which obviously has the same engine as your T100. There is no rev counter so I cannot say for certain but there has always been the feeling that the revs are hanging for a moment after I close the throttle. Doesn't feel like 2 seconds though.
This is in comparison with my two Hondas with carbs. The revs drop instantly when I close the throttle. In fact in many ways the carb system is better. I know the advantages of FI, but I get a much sharper response from the well set-up Hondas. But I guess you get used to (just about) anything, if I didn't have the carbed bikes I probably wouldn't notice.

 

If the revs arent hanging on its as above both my honda and triumph are efi they drop fairley quickly I have cables but my car has no cables it drops a bit slower

 

I have to say, the fuelling on my Street Scrambler (same engine) is nigh on perfect even though it's a 2022 Euro5 spec version which means it runs very lean. Even though the throttle response is good the engine does not spin back to idle as quick as the 570cc single on my dirt bike. A requirement of the Euro5 spec is that fuel is shut off completely on a closed throttle until the engine is back to idle so the slower throttle back response must be purely down to the weight of the reciprocating parts. The difference is the dirt bike engine is a comparatively high revving, over square race bred motor with a lighter crank requiring a higher idle speed to prevent stalling compared to the lightly tuned, lazy road going motor in the Triumph. Even the 1400cc, 4 pot motor in the ZZR revs down quicker than the Triumph!

 

Would need to test run my engine tomorrow....but I suspect its normal....lots of heavy stuff spinning....will take a bit for it to slow.

I will fire mine up tomorrow and report back.

In fact I have a vid I shot last week....will look at that now.

 

.

 

Ok vid of my engine running....how does it compare going back to idle speed.

 

Let us know how you go on....my bike has no cat so that could effect it....the cause a bit of resistance to exhaust flow....so could slow down the slowing.

 

I doubt a cat would effect the rev down as there's minimal gas flow with a closed throttle.

 

Still sucks in air....has to blow it out again.

 

With a closed throttle, the (petrol) engine sucks in very little air, hence the vacuum in the inlet tract/manifold on overun, unlike a diesel where the air isn't throttled and is fully open to atmospheric pressure.

 

Seconds not minutes