Is there anybody who made DIY sprocket / propshaft adapter...
Or rather you just buy readymade ?
I'm looking for 2003 ZX9R adapter, but in Poland they are "not available". So my first thought - let's made one, but... now
I'm little lost.
HI Loony
I think most people buy them, as you would need access to a lathe (and mill for the splines?) and a heat treatment facility, as all the ones I have
seen have been hardened....
I'm sure the Locostbuilders population can figure a way of getting one to Poland on the cheap...!? 
I assume you have tried these guys?
http://www.sprocket-adaptors.co.uk/
Yes - I know them.
I send some inquiries to Polish machine shops if they can make me one, but... I'm still waiting for response 
If I can't find one who make me adaptor or it parts - I will buy one from "sprocket-adaptors", MK or MNR... but in Poland should be
much cheaper (it's not a rule - some things are more expensive here than in UK)
There are "some" polish employees in UK, so it shouldn't be problem to bring adaptor to Poland.
Is there any reason I couldn't weld flange to bike sprocket ? Anyone tried this ?
People weld diffs, so why not flange to sprocket
My friend told me that he can laser cut/CNC some kind of adaptor, but can I weld it to sprocket...
[Edited on 24/2/12 by loony]
I made mine
Took the bike sprocket and cut the middle out on a lathe (very hard metal) and put on a taper, male end.
Grabbed a scrap diff and removed the pinion prop flange, cut the end off and machined a taper so it dropped on the splined lump nicely, female end.
Welded it up, job done.
That's very good news
Any chance for pictures ? But I think I know how you did it
I'll be changing sprocket in my bike - so the old one will go to welding tests
[Edited on 24/2/12 by loony]
Sorry, no pics I had a look 
The centre of the sprocket is untouched, the teeth are very hard so I chopped off with an angle grinder before lathing down.
A taper just makes it centre nicely.
Regards Mark
Thanks Mark, everything is clear now.
I found someone else who made sprocket adapter himself.
tks's sprocket adaptor:
Rescued attachment Foto 006 small.JPG
He's from Spain - so I suspect he had same problem as I
"Doors open" - let's get to work
quote:
Originally posted by loony
There are "some" polish employees in UK,
lol
I would not make one that long, it will waggle about !
It needs to be just long enough to clear the nut on the prop when you do it up, mine is a maximum of 1/2" further forward from where the
sprocket teeth lived.
You could just cut the flange off an old diff and weld on to the teeth of the original sprocket, I used a taper as it made lining up easy, it will
spin at up to 6000rpm when flat out so make sure it is accurate 
Regards Mark
I know it's too long. But tks's engine was V2 so it was complicated.
Rescued attachment 150105 005 small.JPG
Today I looked at my engine, and I need something like 20-30mm spacer - because of cooling tube near the sprocket (something like
"sprocket-adaptors" adapter design).
So I will made flange on lathe, and then weld original sprocket to it. I will make taper like you or just use sprocket's edge to fit it centered.
Or maybe I shouldn't worry about it:
Prop adaptor fitted
It's 40inches's prop adapter - it's tight, but it fit. Unless it isn't Ford flange...
[Edited on 25/2/12 by loony]
quote:
Originally posted by matt_gsxr
I assume you have tried these guys?
http://www.sprocket-adaptors.co.uk/
Last progress...
From this:
ZX9R sprocket before
To this:
ZX9R sprocket after
Now I need flange/adaptor to fit my sprocket...
[Edited on 12/3/12 by loony]
quote:
Originally posted by loony
Or maybe I shouldn't worry about it:
Prop adaptor fitted
It's 40inches's prop adapter - it's tight, but it fit. Unless it isn't Ford flange...
[Edited on 25/2/12 by loony]
Update...
Here's final result: SAE1140 DIY sprocket adaptor
Ready
TIG welded
Total (lo)cost: 22GBP
Not quite the same thing - but back when I was building/racing drag bikes , I used to make my own offset sprockets - anything up to 4" !
I heated up the sprockets to red heat , left to air cool , then machine/weld as needed - I then just popped them to a local heat treaters for
re-hardening .
quote:
Originally posted by loony
I know it's too long. But tks's engine was V2 so it was complicated.
Rescued attachment 150105 005 small.JPG
Today I looked at my engine, and I need something like 20-30mm spacer - because of cooling tube near the sprocket (something like "sprocket-adaptors" adapter design).
So I will made flange on lathe, and then weld original sprocket to it. I will make taper like you or just use sprocket's edge to fit it centered.
quote:
Originally posted by clairetoo
Not quite the same thing - but back when I was building/racing drag bikes , I used to make my own offset sprockets - anything up to 4" !
I heated up the sprockets to red heat , left to air cool , then machine/weld as needed - I then just popped them to a local heat treaters for re-hardening .
Sadly no photos to hand - this was back in the days before digital cameras and the internet.......
Everything was made by hand - and drawings where no more than pencil sketches on scraps of paper.......
I've dug out a few pictures showing the sort of bearing supports I used to make - I'll scan them and pop a couple up tomorrow (bit late
now.....off to bed ! )