Yesterday when leaving a friends house to head home my bike did something kind of wierd I think. I mean it could of been my imagination but I could of sworn the motor kind of coughed for a split second.

Here's the scenario:

Outside temps were in the low 90's.
Bike was warmed up and at operating temp prior to leaving my house.
I had been riding on the street about 10 minutes then stopped at a friends house real quick.
Bike had been sitting at their house turned off for maybe 5-7 minutes.
Fired bike up and started to head home.
I was turning right from a dead stop at a busy intersection.
To quickly get up to the speed and flow of the traffic I rolled into 1st gear moderately (maybe 3/4 throttle) until reaching about 45-50 mph.
Traffic was coming to a stop and the lanes merge from 2-1 so I had to roll off the throttle and prepare for breaking and merge over.
As I rolled off throttle I applied just a hair more throttle and heard the bike kind of hiccup or cough for just a split second.
Pulled in clutch to assess the situation.
It happened so fast that I didn't have a chance to look at the RPM to see how big of a dip it might of took.
I revved the bike a little and it seemed and sounded fine. It rode home fine without it doing it again.

Maybe it was a fluke occurance from getting on the throttle a little then quickly having to get off then back on for a split sec? My VTR1000 used to cough every now and then but that was due to the two massive 48mm flat-side carbs nature. With this being FI bike I wouldn't think this kind of thing would happen. Maybe it was my imagination but I'm pretty sure I hear the motor and bike sort of cough. It didn't make any jolts or noticeable studder that I could tell.

Wondering if anyone else has experienced this or know what it could be? I go for my 600 mile service soon so I'm going to at minimum let them know it happened so there will be a log of it.

Probably normal if it is the fuel cut issue. When you close the throttle at higher than 3500 rpms, the bike will stop the fuel injectors. When you close the throttle, then open it, there will be a very small delay and then what seems to be a burst of power. So if you close, open slightly for a second, then close it again you will get a power kick that will knock you back.

This is an annoyance that a lot of people dealt with by getting Ivans FCE (fuel cut eliminator) product. This issue usually causes me to grab throttle tighter when I get knocked back, which causes me to roll on more throttle. This is a very stupid "feature", but I have not installed the kit.

Yup that sounds like what happened. I will look into buying his FCE if I notice this becomes more apparent. So far its only done it once so maybe it was just the 'right amount' of circumstances to cause it. I'd love to buy the whole Ivan's kit but I'd probably be sleeping in the garage once the wife found out I order more crap

Mine does the same thing once in a while. I'm assuming it's the fuel cut and I'm keeping an eye on it to make sure it doesn't change/get worse.

I'm gonna look at possibly eliminating the fuel cut through an ECU flash down the road.

I get a cough at 2500 RPM. Does anyone know the exact RPM the fuel cuts off at? I'm trying to tune the cough out! I figure if I can add fuel I may be able to avoid it.

Lou

Ivan's page talks about what the what the fuel cut is, and what the FCE eliminates. It lists 3500rpm and over for the Z1000 (no year, but the FCE is only listed for the 2010+ models.)

Originally Posted by sweetlou

I get a cough at 2500 RPM. Does anyone know the exact RPM the fuel cuts off at? I'm trying to tune the cough out! I figure if I can add fuel I may be able to avoid it.

Lou

It is an ECU issue and I don't think fuel maps alone can fix it. This means a PCV won't help (according to Ivan and other people on this forum).

Ivan's site says that he expects to offer ECU flashing this fall. I think there is someone else offering them now for $350 if you don't want to wait. Just search the forum. My bike is stock, but when Ivan offers it I think I might go for it. Recently I started to really hate that issue.

Ivan's page says the fuel cut off is at 3600 RPM. I do not notice ANY change in exhaust sound until 2500 when I get a distinct "pop." I was under the assumption the fuel cut off at 2500 but apparently not. Weird...

Lou

When i got the the euro link ..OZ cbf to call teh guy ... I bought the FCE immediately (which was today ).. then I said oops i just spent 170 AUD...kisses... its for my safety so i get smooth throttle especially on a corner in the wet... she SAID i get he same think in my mazda(cager) it surges... no further comment... Woman accepted it as a need for safety.. REJOICE and EMBRACE half intelligence !!!!

Originally Posted by haknslash

Yup that sounds like what happened. I will look into buying his FCE if I notice this becomes more apparent. So far its only done it once so maybe it was just the 'right amount' of circumstances to cause it. I'd love to buy the whole Ivan's kit but I'd probably be sleeping in the garage once the wife found out I order more crap