Any help very much appreciated, thanks.
Got this ZX12R and it needs rear sprocket replaced, Iv'e removed the diff and don't know how to split to access rear sprocket, been online can't see a thing, no make or markings.

Im a proper donkey and find forums difficult!!! How do you upload a picture?

[Edited on 24/3/20 by Keyzie]

Hi Keyzie,

No idea about your first question, but re posting pics, I've found it best to take the pic on ya phone, minimise it/ re size it/ crop it so that it is less than 2MB then save it to an easily find-able place and then go to your Photo Archive where it will allow you to upload it to your archive, then look at the uploaded pic and at the top left it shows a code, copy and paste that into your post, easy as that, I hope !!

Well it worked for me anyway so good luck with all of your questions.

Jason

Hi Jason
Many thanks for the info, will give it a try.

Regards
Adrian

Are these pics of any use.....

MK midi

Hi

That rear end looks very similar to the MK GT1 (probably identical) that I built some years ago.

Unfortunately, unless the sprocket is a split one, then you will need to disassemble the back end, take the drive shafts out and then remove the diff from the diff carrier to be able to remove the sprocket.

The diff carrier is bolted together. Undo the bolts and remove the housings from the bearings (you probably only need to remove the housing on the sprocket side).

If I were in your position I would look at sourcing a split sprocket replacement so that you only need to do the pretty major disassembly of the rear end this time.

I understand that a split sprocket is a bit harder on the chain, but I think it would be worth an extra bit of wear on the chain for ease of changing the sprocket in the future.

Hope you manage to get it sorted.

Mike

Hi Mike

Many thanks for the reply, your so right about that split sprocket, I might even try cutting it off or i'l have to find a CAPABLE engineer and that'll be a proper ball-ache, I couldn't work out how this splits from the cradle so I can replace sprocket, may I ask the rear sprocket is huge on this, do you know if these are custom made or off-the-shelf bike parts, even though its a Kawasaki engined car theres probably lots of mixed bits thereon.

Regards

Adrian

Hi Adrian

You should be able to split the diff carrier yourself. Obviously the bearings are a good fit so will probably need a bit of persuading.

It looks like you have a Quaife limited slip diff in there, so the sprocket just bolts up to the flange on that.

You are right, the sprocket is huge compared to a standard bike one. This is to reduce the gearing so that the bike engine can cope better with the increase in weight of the car (and potentially passenger) compared to the bike.

Bear in mind that in the bike application it was geared for a top speed approaching 200mph, where in the car it would be 120-130 ish max top end.

The original sprockets were laser cut specials supplied by MK. Mine was a 53 tooth and was like yours, a one piece one.

There are several suppliers of sprockets. There are a few that come to mind below:

http://www.abperformance.co.uk/

http://www.mksportscars.com/parts/sprocket-adaptors/aluminium-sprocket.html

http://www.kitcardirect.co.uk/aluminium-sprocket.html

https://talon-eng.co.uk/products/sprockets/ Talon will make what you want and will make it split for about £2 or £3 quid extra.

Assuming your diff is a Quaife ATB (It most likely is), all of the above know about this diff, the hole sizes and PCD so you should hopefully be able to find what you need.

Hope this is some help.

Cheers

Mike

Hi Mike

Very much appreciated, found exactly what I needed through one of your links, will have a go at it myself, it's a bugger shape of a thing to secure and work on but it needs doing as the chain/sprocket wear can be felt throughout the car, when sorted car will be 100%

Please could I send you some pictures of the diff as you will know better than me what your looking at, I spoke with Quaife and they said it wasn't one of theirs, although he didn't sound too clever, I think it is Quaife, just trying to establish what im looking at, when I bought it I was told it was a Quaife LSD, I don't know?

I don't know how to post pic's on here!!

If possible would you be so kind, do you have an email acc I could send images too? Let me know if you think it's def a Quaife (theres 3 years where I have no car history so may well have been rebuilt at one time or another)

Regards

Adrian

I've sent you a U2U with my email address

Apologies for this I can see you sent me something at 1529 but I can't find the message, please am I doing something wrong, when I click on Highlighted 'You have 1 new u2u message(s)' the link ain't working!

Thanks
Adrian

It's OK got pic's sorted

Thanks