South West Bikers | Motorcycle Forum

On a 2006 kwak zx6r 636 Just wondering if there is any real gain from changing a rear sprocket from 43 to 45 teeth?
The manual says 15/43 so I’m guessing the standard sprocket is 43 teeth as I have a 45 aluminium one.
Not sure what the front is..

It'll Give you a little better acceleration but will also make your Speedo inaccurate.
I believe normal ratio is 3 to 1 to keep the readout true

Going +2 on the rear sprocket makes sense if you're riding on track, it's probably the most common mod to pep up a bike's acceleration out of corners and gives a better chance to use all the bike's speed before the straights end. On the road it's debatable whether it's worth the effort - the speedo will be even more inaccurate (they always over-read slightly, this will be exaggerated by the gearing change - a further 5% in this case, but you'll sound really impressive with your top speed tales in the pub), and how much do you need that extra punch out of corners on the road?
Still, you pays yer money, you takes your choice - entirely up to you

I also have a ZX636 track bike and got to say that i would really struggle to top out in 6th gear on a UK track so gearing for acceleration is not a daft thing to do. If this is for the road as said earlier not sure that it would really help as to get into the torque band you have got to be screaming the thing in a way you only really do on the track.

If you do decide this is something you want to do and your going to carry on using it for the road then would highly recommend getting yourself a "Speedo Healer" I did this mod on my GSXR 1000 K7 and fixed the speedo inaccuracy and also makes sure that your mileage is calculated correctly (as this is something else that the gearing will change without you realising it)

Please let us know how you get on. I am having work done to my ZX636 at the moment as i blew up the engine at Donington earlier in the year and this might be a mod that i might consider as well.

This is not a track Bike Rob, it's Road only end his first Bike.

Only comment I would make is that (for a road bike at least), unless the components are almost new, it's generally advisable to change both sprockets and the chain at the same time - old chain on new sprockets, or vice versa, will wear the new item out double quick. Also, for road use, the "benefits" of an ali sprocket are moot at best - you're better off sticking with a quality steel item

Thanks for the advise all!
Yes, it is just a road bike and yes, it’s my first bike. The rear sprocket was changed to an alley +2 by the previous owner, I’ve not checked the front sprocket yet. These may sound like daft questions I’m asking but it is my first bike so be gentle lol

For future reference what would be the best chain and sprocket kit to buy and where to purchase it?

Everybody has to learn sometime

I've always tended to use DID chain - you do get what you pay for! I have also used Afam, which were good too ..... Others will hopefully chip in with personal experience too.

If you're not sure about fitting a rivet link, take it to someone who can show you how to install them properly as there's a knack to it. Avoid split links wherever possible on a mid size road bike upwards - other than for a short journey to get the rivet link installed

Places like mandp or busters do good kits, they can normally be found on ebay listed as specific for you bike.

Afam are good but DID every time because the soft link is easier to install.
For perfect fitting, check the width of the link with a vernier to compare it with the average link width.

I was also going to say DID as that's what I have used as well.

But would really recommend checking this out if your changing this on a road bike.
https://www.healtech-electronics.com/products/sh/

I would say for a road bike though might not be worth the costs for the benefits that your get from it. But your choice.....

I always use DID chain (for the reasons mentioned above) with soft link and JT sprockets (personal choice) because JT do a front sprocket with rubber cushions on side faces, they really do quieten the chain noise down.

Doddy wrote: ↑Oct 17th, '24, 16:55 On a 2006 kwak zx6r 636 Just wondering if there is any real gain from changing a rear sprocket from 43 to 45 teeth?
The manual says 15/43 so I’m guessing the standard sprocket is 43 teeth as I have a 45 aluminium one.
Not sure what the front is..

According to Gear Commander: https://www.gearingcommander.com , with your sprockets at 15 front/45 rear your Ninja would have a top speed loss of 7.3 mph against the standard 15/43 gearing setup (165.1 mph stock/157.8 mph custom, both @ a theoretical 14,000 rpm) - with slightly snappier acceleration, but also a slight loss in mpg of course and, as noted by Simon, your speedo would read wrong - unless it's been Tune-Ecu'd to compensate.

If you're interested in the various ramifications of different gearing, set some time aside and have a good look through the above website. I've set it up in advance for your ZX-6R but have a good play and see what's possible. My personal opinion, as it's your first big bike, is to consider keeping it bog standard until you're completely confident in your abilities - it's a quick enough bike exactly as it is. Good luck, stay safe and enjoy getting to know it .

no advantage on the road, keep it stock.