A favour please - could somebody with an R1 kindly measure the length of the splined output shaft for me, ie the length of the part of the shaft that has splines on it to see if my engine is different or if Ive been supplied the wrong part.

I got my MK prop flange/adapter through the post yesterday and its hardly any better fit than the blade one Ive already got!
The old blade one is 17mm deep where the splines are, the new MK R1 one 15mm, but the splines on my engine (a 2003) are only around 12mm and the actual sprocket off the bike is around 10mm which is what the flange needs to be to allow for a splined locking washer to sit on the splines to hold the nut. So, the MK prop adapter appears to be around 5mm too thick for what I need it to be.

cheers

Chris

Chris - the nut that holds the sprocket on is recessed on one side - one way round you get wobbly cog syndrome, other way round it tightens properly.
Ah - just re read & problem's the other way - I'll go and measure the splines... 12.23mm
I turned an adapter up on my lathe that clamps the old sprocket - it's in me photo archive if you fancy the DIY route
Cheers
Bob

Cheers Bob, sounds like the same thickness as mine then so I guess MK have probably supplied me a blade one by mistake
Personally I don't fancy modding a sprocket as I have heard that a few of those have failed before (I think Dax used to supply them and had problems but I might be wrong). I could have gone the part DIY route with my old blade one and got that machined down but it was hardened so too hard to machine, so I got the MK one for "convenience", rather annoying that its wrong and probably will now prevent me getting it back on the road next week

BTW, I just had a look at your DIY one and it is a lot better made than the ones Ive seen modded before so I think one like yours will be fine, but for me I just wanted one off the shelf that works and not have to go through the effort of making one

Cheers - the bolts holding it together sit in the 'divots' in the cog - I wouldn't fancy machining or welding the cog, it's clearly made out of some 'moon metal' much harder than HSS!
Bob

Steel bike sprockets are case-hardened, which means they're heated 'til cherry-red and quenched in carbon. This causes a very hard layer to form on the surface. The more you repeat this prcoess, the thicker the layer becomes, making it not disimilar to moon-metal!

My MNR flange was too deep, but Marc managed to skim it down as he didn't have another R1 flange in stock. So far it's been fine (1700 miles of enthusiastic driving.....).

[Edited on 18/6/05 by Coose]

I had approx 5-6mm machined off my ST prop adaptor at my local machine shop.

They said It was bloody hard but still only charged me a tenner.

Ive spoken to MK this morning and it appears the machinist has forgotten to machine off one of the lips to make it R1 compatible. Although its hardened it does appear softer than my old blade one, so I'll get my uncle on the case to see if he can machine this one, otherwise it needs to be sent back to MK, be machined then sent back again (none in stock they can ship out immediately).

Chris

just undo the hardened...

skin make it cherry red again..
and let it cool down by itself..

and you are done..

Tks

and try to make it cool slowly.

Nah seeing as its MK's problem, Im not going to faff around with it too much. If I cant get it machined easily myself then it will go back to MK and they can do it