Forgive the delay, I've been working on this article for awhile. It's a lot of information that we've learned and implemented over the past couple years of racing the Ninja 400 in AFM, CVMA, WERA, and MotoAmerica. I hope it helps everyone understand what is going on and how we fix everything so that it's reliable for track or everyday use.

Kawasaki Ninja 400 Clutch Slipping, Poor Shifting, False Neutrals, and Dropping Gears - Explained and Fixed!
https://www.norton-motorsports.com/wp-content/uploads/2019/12/open-clutch.png (https://www.norton-motorsports.com/2019/12/kawasaki-ninja-400-clutch-slipping-poor-shifting-false-neutrals-and-dropping-gears-explained-and-fixed/)

Looking no forward to the details.

Looking no forward to the details.

Click on the title immediately above the photo.

So, is the 400 even a good buy? I'd personally be jumping down someone's throat if I bought a new motorbike and it had these problems.

Click on the title immediately above the photo.

Thanks!

Thanks!

I’m happy with the bike. But the transmission does leave a little to be desired.

I was getting the dropping out of 5th going to 4th when I changed gears at high rpms on the track. I did the clutch spring arm assist and the heavy duty Barnett Clutch springs and the issue was cut down dramatically. Two of my friends have the 2018 400 as well and they aren’t having this issue, only I was.

Oh how we get spoiled with electronics and automatics! Over 99% of autos and bikes in world are manual. On recent trip to Europe, we had to call ahead and get special accommodations to rent car with automatic transmission because my dad’s getting older and step-mother can’t drive manual.

Anyway, back in ‘80-90s, pretty much ALL bikes slipped gears when put to hard use like racing. Common practice was to undercut shift dogs on gears to pull them together under load. Let’s see if someone figures this out for Ninja 400.

So, is the 400 even a good buy? I'd personally be jumping down someone's throat if I bought a new motorbike and it had these problems.

Most certainly is!!! All reported problems have come from racing situations or high-RPM/high-load use. Which will affect only tiny, tiny percentage of street users. So little work to upgrade those springs.

For price, you cannot get better performance on street or track. It really spun AFM’s classes around this year as they originally put it in with 300s. It completely dominated that along with Lightweight & Middleweight Twins, beating up on SV650s. Also always took top-5 in cripple 450s (600ss with disabled cylinder). As well as placing top-10 in 600SS, 750sbk, and Literbike classes (beating 30–40 others in field). There’s no other bike right now that can get as many points in so many classes!

Speaking of bang-for-buck, there’s some brand new ones being clearanced at local dealer for $3750. Gonna go take look good this weekend.

I was getting the dropping out of 5th going to 4th when I changed gears at high rpms on the track. I did the clutch spring arm assist and the heavy duty Barnett Clutch springs and the issue was cut down dramatically. Two of my friends have the 2018 400 as well and they aren’t having this issue, only I was.

The dropping out of 5th issue seems to be pretty bike dependent, likely due to the quality of the cast gears in the transmission, how precise they are, and how well they mesh. Some bikes seem to be much worse than others.

Oh how we get spoiled with electronics and automatics! Over 99% of autos and bikes in world are manual. On recent trip to Europe, we had to call ahead and grt special accommodations to rent car with automatic transmission because my dad’s getting older and step-mother can’t drive manual.

Anyway, back in ‘80-90s, pretty much ALL bikes slipped gears when put to hard use like racing. Common practice was to undercut shift dogs on gears to pull them together under load. Let’s see if someone figures this out for Ninja 400.



Most certainly is!!! So little work to upgrade those springs. For price, you cannot get better performance on street or track. It really spun AFM’s classes around this year as they originally put it in with 300s. It completely dominated that along with Lightweight & Middleweight Twins, beating up on SV650s. Also always took top-5 in cripple 450s (600ss with disabled cylinder). As well as placing top-10 in 600SS and Literbike classes (beating 30–40 others in field). There’s no other bike right now that can get as many points in so many classes!

Speaking of bang-for-buck, there’s some brand new ones being clearanced at local dealer for $3750. Gonna go take look good this weekend.


I talk about transmission undercutting in the article and we do offer it for the 400. It's pretty much mandatory for top race teams these days with these little bikes that aren't undercut from the factory like the new supersport and superbikes are.

Most certainly is!!! So little work to upgrade those springs. For price, you cannot get better performance on street or track. It really spun AFM’s classes around this year as they originally put it in with 300s. It completely dominated that along with Lightweight & Middleweight Twins, beating up on SV650s. Also always took top-5 in cripple 450s (600ss with disabled cylinder). As well as placing top-10 in 600SS and Literbike classes (beating 30–40 others in field). There’s no other bike right now that can get as many points in so many classes!

Speaking of bang-for-buck, there’s some brand new ones being clearanced at local dealer for $3750. Gonna go take look good this weekend.

I've fixed this very issue with my ex250, but those springs had about 35k miles on them. having this happen right out of the factory just kind of makes me nervous is all.

I love the z400 after comparing it with the Ninja 400 at my local dealership and feeling what they've done for the suspension and riding position (as well as tuning, I hear) to make it more of a street-specific bike. It's between the Z400 and the SV650 for me. They're afraid to let me test ride at either my local Kawi or Suzuki dealership despite the fact that I can afford the bike (I assumed that being over 21 and having 5 years of riding experience would be enough for them. Guess not), So I'm going to hop over to a different city and see if I can get some saddle time.

On Kawasaki website, under locate dealer, you can search for one that offer test rides.

That's helpful in narrowing it down! Thanks!

the 400 is still small and light enough to be a direct comparison to the ninja 250, and powerful enough to compare it to slightly larger bikes. it out performs Honda's 500, with some bolt on parts its very close to the power output of the ninja 650. I think this is the bike i have liked the most out of the 7 road legal bikes i've owned.
ninja 400 can reach 53 hp with very minor bolt on parts, and the 650 is about 64 hp at the wheel. not to mention the 400 is much lighter than the bigger 650.

You get a lot more leg room with the 400 too though. I still have a 2003 Ninja 250.

Yes, 400 has ergo for bigger riders. Lower pegs, taller bars.