Gearing thread

129207 Views 376 Replies 66 Participants Last post by JFMNINJA400, Apr 1, 2022

Kiwi Rider

Discussion Starter · Mar 18, 2018

If I've got one pet hate (uh no, I've got heaps actually!) it's listening to a bike screaming away in top gear when your travelling long distance. Even worse if your slip on is too loud Ha ha.
I've decided the N400 falls into this category after a long ride today on mostly straight roads. At 120kph/75mph your sitting on just over 7K RPM, too much IMO and it makes your fuel economy suck too.

So I've decided to change the final reduction ratio from 2.93 (41/14) to 2.71 (38/14). I could also go to 2.73 by adding a tooth to the front sprocket which is close but I don't want to bring the axle any further forward in the slot.
Better to drop three teeth off the rear sprocket which is basically raising the gearing by 8%.
This should make my speedo read more accurately too as it's a bit optimistic. I can tell from the speed radar advisory signs we have here.
I may need to take a link out of my chain though.

I'm going to get a 38 tooth 520 blank made out of aluminium and I will machine the center out to suit the hub diameter and drill to suit for sprocket bolts.

Does anyone with a Ninja 300 know if the front sprockets are interchangeable?. This would be really handy info to know. Rear as well.

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Engine-R

· #2 · Mar 18, 2018

Kiwi change the gearing to 38/14 means to take 2 links away from the chain or place the rear sprocket 13 mm (1/2 inch) more back.
From the pictures the parts (sprocket, hub ect.) look the same, but since the german parts catalog doesn't show the real parts number (only a reference number is what they have now) I can't say if they are equal.
On the attached picture you can see the gearing with 38/14 setup.

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Kiwi Rider

Discussion Starter · #3 · Mar 18, 2018

Engine-R said:
Kiwi change the gearing to 38/14 means to take 2 links away from the chain or place the rear sprocket 13 mm (1/2 inch) more back.
From the pictures the parts (sprocket, hub ect.) look the same, but since the german parts catalog doesn't show the real parts number (only a reference number is what they have now) I can't say if they are equal.
On the attached picture you can see the gearing with 38/14 setup.

Thanks for that. I can see that at 100kph (our speed limit) the new gearing ratio will drop the revs from 6000 to 5,500 which is a good difference.

Yes I'm also wanting to move the axle back in the slot more for extra stability.

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SDM!

· #4 · Mar 18, 2018

The 300 and 400 share the same sprocket front and rear. I have already changed my rear sprocket from my 300 to my 400.

My 43t Tyga from my 2015 N300

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Kiwi Rider

Discussion Starter · #5 · Mar 26, 2018

SDM! said:
The 300 and 400 share the same sprocket front and rear. I have already changed my rear sprocket from my 300 to my 400.

My 43t Tyga from my 2015 N300

So you've geared it down by adding two teeth to the rear, opposite of me. You must like close ratios huh? I'll bet it's quick through the gears! Do you find 1st a bit low?

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Kiwi Rider

Discussion Starter · #6 · Mar 26, 2018

8

So I spent a bit of time on the weekend doing the gearing change I mentioned in my previous thread. Changing the rear sprocket from a 41 down to a 38 tooth.

First I had to machine out the centre of the 38 tooth blank to suit the N400 sprocket carrier:

Then I had to drill the holes for the sprocket bolts using the OEM sprocket as a template. I also drilled some larger lightening holes as well:

After a bit of elbow work with some scotch brite to polish it up a bit I fitted it to the sprocket carrier and then the wheel:

I was pleased to find after tensioning the chain that the rear axle had only moved half an inch further back in the slot from where it was before. So I still have considerable adjustment left before I need to start taking links out of the chain and fitting a joining link. I don't want to butcher the OEM endless chain before it's worn out.

Out on the road first gear is now much more usable and you can get a decent amount of momentum on before you start reaching for 2nd. Through the gears the ratios still feel close enough for my liking and there's no big holes there but sure, its maybe not going to do quite the same 0-60MPH time as before but there wouldn't be much in it and I'm not bothered.
What is good is the more relaxed cruising in top gear. 5,500RPM at 100kph / 60 mph.
At 7K RPM I'm now doing 128kph / 80mph. So much better for sustained high speed runs.
It feels like you could get away with dropping another tooth yet to 37 but then perhaps you would start to notice the wider ratios and first gear may require a little more slip of the clutch to get going.

So I'm really happy with the bikes gearing now but one thing I did confirm is that the speedo does not run off the transmission (as it did on my CBR) so I have not corrected the speedo error.
Cant have every thing in a modification eh. :grin:

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xParaaz

· #7 · Mar 26, 2018

Ninja 400 Gearing (Sprockets)

Has anyone gone up or down any teeth on their 400’s yet? I rememember hearing that it wasn’t really worth it on the N300 due to its small engine size, has this changed with the N400?

Eager to hear about anyone else’s experiences.

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Kiwi Rider

Discussion Starter · #8 · Mar 26, 2018

xParaaz said:
Has anyone gone up or down any teeth on their 400’s yet? I rememember hearing that it wasn’t really worth it on the N300 due to its small engine size, has this changed with the N400?

Eager to hear about anyone else’s experiences.

Have merged your thread to here where you will find some info.

Reactions: 1

thewittes1

· #9 · Mar 28, 2018

Kiwi Rider said:
So I spent a bit of time on the weekend doing the gearing change I mentioned in my previous thread. Changing the rear sprocket from a 41 down to a 38 tooth.

First I had to machine out the centre of the 38 tooth blank to suit the N400 sprocket carrier:

Then I had to drill the holes for the sprocket bolts using the OEM sprocket as a template. I also drilled some larger lightening holes as well:

After a bit of elbow work with some scotch brite to polish it up a bit I fitted it to the sprocket carrier and then the wheel:

I was pleased to find after tensioning the chain that the rear axle had only moved half an inch further back in the slot from where it was before. So I still have considerable adjustment left before I need to start taking links out of the chain and fitting a joining link. I don't want to butcher the OEM endless chain before it's worn out.

Out on the road first gear is now much more usable and you can get a decent amount of momentum on before you start reaching for 2nd. Through the gears the ratios still feel close enough for my liking and there's no big holes there but sure, its maybe not going to do quite the same 0-60MPH time as before but there wouldn't be much in it and I'm not bothered.
What is good is the more relaxed cruising in top gear. 5,500RPM at 100kph / 60 mph.
At 7K RPM I'm now doing 128kph / 80mph. So much better for sustained high speed runs.
It feels like you could get away with dropping another tooth yet to 37 but then perhaps you would start to notice the wider ratios and first gear may require a little more slip of the clutch to get going.

So I'm really happy with the bikes gearing now but one thing I did confirm is that the speedo does not run off the transmission (as it did on my CBR) so I have not corrected the speedo error.
Cant have every thing in a modification eh. :grin:

Wow! Good work. I'm a fan.

Reactions: 2

SDM!

· #10 · Mar 28, 2018

Kiwi Rider said:
So you've geared it down by adding two teeth to the rear, opposite of me. You must like close ratios huh? I'll bet it's quick through the gears! Do you find 1st a bit low?

I will be looking for being top speed by the end of the straight before hitting turn 1. I will have to order a bigger one for the rear (or drop 1 in the front) for the 2nd track we have in Philippines. I will find out for sure on April 7th. We will be hitting BRC. As it turns out I think 1/2 of the owners of the N400 will be there that day. I dont know if it will be good or nuisance as a lot of riders will be first time ever on the track.

The last time I had NEWB riders they almost killed me. Was hauling ass on my ZX10R down the straight a [email protected] pulled out of pit lane right in front of me. Talk about panic braking! once I got it stopped and forced him to pull over this was his words (I thought I could out run you.) My words no need to mention here, but not nice. Once we got back to the pits we changed the group order for going out. Newbies go then we go.

With the new guys going this time we will make sure we discuss track etiquette.

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SDM!

· #11 · Mar 28, 2018

@Kiwi Rider

AMAZING TALENT my friend.

I wish I had your garage and your skills. :BOWS DOWN: :clap:

Kiwi Rider

Discussion Starter · #12 · Mar 28, 2018

SDM! said:
@Kiwi Rider

AMAZING TALENT my friend.

I wish I had your garage and your skills. :BOWS DOWN: :clap:

Thank you. I tend to take the skills side of things for granted a bit as it's my job but not the fact that my workplace lets me use the facilities after hours. A huge bonus.

Regarding your track days. I understand your nervousness surrounding first timers. Luckily we are always segregated at my track in separate classes. I try to remind myself that I too was once the newbie track rider out there going in too hot and running off onto the grass and all that good stuff.

.
I'm sure they will have a ball - hopefully without too much carnage!

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Rider2112

· #13 · Mar 28, 2018

^^ +1
First track day can be a bit stressful, but its really an amazing experience.

I expected to be a complete bundle of nerves, but really wasn't bad once we got lined up to go out. Wife was the opposite, she was all good, but was an absolute wreck by the time I pulled back into the pits, lol.

Just be prepared for a few out there to be less courteous to others. No passing in the turns in the novice group isn't always honored, etc..

Its an amazingly worthwhile and humbling experience, and you'll learn a TON.

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rde09

· #14 · Apr 7, 2018

Up one tooth in the front

SDM! The 300 and 400 share the same sprocket front and rear. I have already changed my rear sprocket from my 300 to my 400.

My 43t Tyga from my 2015 N300

I am going to take your word for it and order a Ninja 300 15t front sprocket for a 7% change in ratio and thereby missing the dreaded CEL with an 8% ratio change.

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Ninja400 Stealth

· #15 · Apr 7, 2018 (Edited)

2

Try the Gearing Commander site!

I was experimenting with my 2013 Ninja 300. And after trial and error and some research. I did a 15f and a 43 Rear on the Ninja 300 and really it was close to the same as running as a 14 tooth f and 40 tooth on the rear that seemed to give it that "JUST RIGHT" ratio for this machine... I believe, I used a 15 tooth Sunstar for the Front and then a VORTEX CAT 5 Aluminum 43 tooth on the rear. I also did a Gold X Ring Chain for the setup and even my Speedometer was "DEAD ON". ..I used a Garmin GPS to verify my speed. The First Gear went pretty well. Not to wide and not too short. In 6th Gear on the 300. I was tacking 7221 RPM at 70 MPH. At 80 Mph I was tacking 8252 vs 8636 for the Stock Ratio. All in all I really liked my setup on the Ninja 300. It accelerated just about as fast as stock and seem to actually cruise on the highway more better. With a DEAD ON ACCURATE Speed reading on the Speedometer. I am soon going to take some Garmin Readings on the 400 and may even consider either dropping 2 teeth on the rear or doing a 15f and 43R combo like I did on the 300.....OR, I may do a 14T on the front and perhaps do a 39 tooth on the rear. I still will possibly order a New VORTEX CAT 5 (really like the looks of that one) and see what happens. I just thought I would share this for all concerned. By the way here is the Link for the Gearing Commander site that will prove very useful in making a determination for a Gear Ratio set up. And soon they should be adding the New Ninja 400 to its database. Enjoy https://www.gearingcommander.com/:smile:

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rde09

· #16 · Apr 7, 2018

Hockeynut said:
Found a site here that sells blanks. 36 tooth for a little over 34 bucks seems a bit pricey just for a blank.

https://shop.pbisprockets.com/product.sc?productId=503

Still looking around but figured I would share. Anyone found a cheaper place?

Hockeynut, just remember, when you go past the 7% gear ratio change you get a check engine light on the dash after a few miles. (See kiwi riders thread about check engine light problem)

Reactions: 2

Kiwi Rider

Discussion Starter · #17 · Apr 8, 2018

Hockeynut said:
Ha...A fellow Toolmaker ( Machinist ) like myself. Would like to do the same here Kiwi Rider. Curious where you found the 38 tooth 520 blank from and can a 36 tooth blank be found?

Sounds like you got it sorted (I've been away racing today) The blanks actually come from Italy and I get them through a local importer called Euro bike.
es, I paid the NZ equivalent of $36USD for mine so what you quote sounds about right.
All the best with your tinkering.

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rde09

· #18 · May 12, 2018 (Edited by Moderator)

15T up front?

Pat said:
... Also, swapping to a 15T up front makes the RPM band a bit wider and really opens things up.

Pat, just curious if you have swapped to a 15t up front and if there was any check engine lights initiated afterwards?

I really like the gearing with the 15t up front, but don't like the on again off again of the CEL status.

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Ninja400 Stealth

· #19 · May 13, 2018 (Edited)

Gearing Commander just added the Ninja 400 on Datatbase

Hey Guys, They just added the Ninja 400 to the Gearing Commander Site and Database. Really great tool for Sprocket changes, percentages and RPMs throughout the rev range. Just put a 39T Vortex CAT 5 Red anodized on my Bike and it really does pretty well. It gave it a more wider Ratio and it seemed not to hurt me much on the low end. So now it is 14-39 and or I could do something similar if I went to a 15-42 which would be really close according to the Gearing Commander site which would be just a fraction lower gearing than the 14-39. I did this to my Ninja 300 and it really worked PERFECT and it gave me perfect readings on my Speedo.... But unfortunately it did help my Speedo readings on my Ninja 400. But it is not right on like my Ninja 300 was. If I do 60 MPH on my Bike. My Garmin GPS reads 58 MPH. And even at 75 it is reading 73. So anyway. I may try for a Speedohealer Option to get it right on the money. I sent an E-mail to Speedohealer or Heal Tech to see what Modules or Options would work for our 400s. And the Diagrams to Install one. https://www.healtech-electronics.com/products/sh/.

Also here is a link for the Gearing Commander site too. Hope this helps with the Gearing:smile:https://www.gearingcommander.com/

By the way here is a Pic of the Vortex CAT 5 that I have on my Bike. You can get one for around $63 on E-Bay with free ship.

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Pat

· #20 · May 13, 2018

rde09 said:
Pat, just curious if you have swapped to a 15t up front and if there was any check engine lights initiated afterwards?

I really like the gearing with the 15t up front, but don't like the on again off again of the CEL status.

No CEL yet, everything seems nominal. I am running a flashed ECU though. Wife is going to ride it today, we'll see what happens.

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