My Kawasaki Z900RS feels rejuvenated after a $300 ECU tune! 5 changes

With Akrapovic/Black Widow/Delkevic 4-2-1 decat header + K&N airbox mod, there's about 10 more bhp to be squeezed out.

BHPian amol4184 recently shared this with other enthusiasts:

Last week brought an important change to the Z. Since the bike is new (to me), I thought of getting the ECU remapped before I lost the steam.

For this bike, there are two major tuners: Ivan's performance and 2wheeldynoworks (2wdw). Ivan's is thousands of miles away on the East coast, 2wdw is local, about 10 minutes from my workplace. For Ivan's, I had to pry out the ECU and ship it via post, then wait for it to arrive back. For 2wdw, I could simply ride to the shop and have the ECU flashed as I waited.

There are not many direct comparisons between the two, but in general, Ivan's seemed more popular to me. I decided to stick to 2wdw for the convenience. Once you have the ECU flashed, you can have it flashed unlimited times as long as you own the bike. It was a no-brainer. 2wdw it is. Then I rode to 2wdw's shop for the ECU remap.

The remap took just 15 minutes as I lingered outside and the bike was back in my hands. The changes in engine characteristics after the remap are immediate and impressive.

Here's what changed:

1. Jerky throttle/clutch modulation is almost gone. Not 100% but it is a VAST improvement over stock.
2. Increased grunt all across the rev range. Bike feels like it just drank a gallon of RedBull.
3. Sudden on/off throttle while slowing down and accelerating is gone.
4. Rev limiter increased to 10.5k from 9.8k but I haven't verified.
5. Power increased by an unknown number as I did not dyno the bike but as per the owner, Z900RS gains 5-6 bhp on stock exhaust, as per his experience with past Zs he worked on. More than outright power though, it's the overall punch that's gotten better.

What did not change:

1. Super high cold start idle remains at 2600-2700 rpm. There is an easy fix for that as I later found out. DIY coming for that in a few days.
2. Fuel efficiency may drop by 5% per the tuner. I haven't noticed any drop yet. FE remains around 44 mpg in mixed conditions.

$300 well spent in my opinion, as the bike feels rejuvenated. It's a revelation, really.

With Akrapovic/Black Widow/Delkevic 4-2-1 decat header + K&N airbox mod, there's about 10 more bhp to be squeezed out. Once that hardware is in, another ECU remap will be done. Had a little discussion with 2wdw folks regarding headers. Akra is $1000, Delkevic is $300. I think I know which one I am getting.

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