Front sprocket distance collar

[Steve Cooke]

Would anybody know the service limit for the front sprocket distance collar on a Z1000A1 mine measures marginally under 22mm and my chain is rubbing on the inner casing my front sprocket is a 15T E525 and the inner face is raised 1mm the parts book doesn't show anything other than the distance collar behind the sprocket to space it off the casing, the bike is running an EK630 chain any suggestions as to why would be appreciated, could this collar have worn to that degree? would it be ok to use a washer between the collar and the back of the sprocket to gain an extra couple of mm?
Steve

[Keefleaf]

`allo steve, not completely sure ,but I think standard ZED had 530 chain and the extra will chew the inner plate screw heads off.
I`m on the Isle of wight,if you fancy a pint some time give us a shout,
cheers bud ,Keith
www. aquablasting co.uk

[Steve Cooke]

Alright Keith, I've just added that my bike is a Z1000 A1 the parts book does show it as having a 630 chain originally, the pint sounds good though.

[cra-z1]

Make sure your sprocket has a boss on one side. If it does not you need to add a spacer between the sprocket and collor for the 630 chain. Go to Z1 ENTERPRIZES and look at their sprocket detail and you will see what I mean. They offer two sprockets one with the boss and one with out, and they offer the spacers.

[cra-z1]

Also the reason for the spacer is due to the O-ring chain. If your 630 chain is not an o-ring their is another problem. But the o-ring chain needs the spacer, to make up for the added thickness of the chain.

[cra-z1]

Sorry I missed the fact that you sprocket does have a raised boss. I don't think there would be much wear on the spacer. So I'm not sure what the problem is. A thicker spacer would probably be fine.

[Rich]

Apart from compression under load from tightening the nut up the only wear on the spacer will be made by the oil seal. Stick a washer between the sprocket and spacer to give a little extra clearance if you want.

[Steve Cooke]

Thanks cra-z1 and Rich, The distance collar has small burrs on the outer face that is why I wanted to check the length, I do have a washer which is about 2.5mm thick which fits over the shaft nicely but my concern over using a washer is that when I tighten the sprocket nut up will it not put undue pressure on the shaft bearing which the collar pushes up against?
The chain I got is supposed to be the standard for early Zeds my parts book says for Z1000 a 630s the Enuma chain I have got says 630ms i'm not sure of the difference between s and ms and although the chain I took off is a 630 it is 3mm overall narrower than the new one, the new chains side plates are about one and a half times the thickness of the old one, both chains are non o-ring. You would think it would be simple to figure out why it rubs but it has got me baffled, it seems like the parts are all correct.
Steve

[cra-z1]

Yes that is strange. I would think that the non o-ring chain would have no problem with clearance. Do you have the boss end of the sprocket against the collar? I will measure the thickness of my O-ring chain tomarrow for comparision to yours.

[Steve Cooke]

Hello cra-z1, Yes the boss is against the collar also this boss on both of the sprockets I have is only raised by about 1mm is this correct,on the Z1 Enterprises site it looks a lot more but no dimension is given.
Thanks Steve

[cra-z1]

I just recently installed a sprocket from Z1 part # EM95-29215 and is a 15 tooth JT sprocket. My chain measures 25.4 MM across. Looking at the JT on line catalog the sprocket measures 10 mm including the boss. This may help you to determine if your sprocket has enough clearance. If your chain is smaller across I'm not sure why it would be rubbing, unless your sprocket is alot thinner across. Let us know

[Rich]

"I do have a washer which is about 2.5mm thick which fits over the shaft nicely but my concern over using a washer is that when I tighten the sprocket nut up will it not put undue pressure on the shaft bearing which the collar pushes up against?"


As long as the washer doesn't interfere with the seal and the sprocket is fully on the splines it will be fine.

[Steve Cooke]

Thanks for the input guys, As it stands the shaft bearing feels good no side play at all a little end float which is taken out when collar/ sprocket/ nut is fitted, it all looks fine to me as when the collar is fitted the outer face protrudes about 1mm from the seal this then leaves 11mm of splines showing which is exactly the same as my sprocket (sprocket is 10mm thick plus 1mm boss) this seems ok to me the nut then tightens up to the face of sprocket which is flush with the ends of the splines, once installed at it's worst point which is a slightly raised section of the inner transmission cover which is between 7and 8 o'clock as you look at it, at this point there is 7mm clearance between the inside face of the sprocket and the cover this is not enough for my chain which is 25.4mm over the pin and as there is a couple of mm side play between the chain and sprocket when it is pushed over to one side there is between 7 and 8 mm of chain link to run through this gap is it just a case of not being able to fit this size chain without resorting to an offset sprocket which I presume would have to be recessed also to allow the nut to contact the end of the splines and if so what chain should it be as 7mm clearance seems pretty close to me i'm not sure about the 2.5mm washer option as it brings the sprocket off the splines by the same amount giving reduced meshing area on the splines and when the nut is tightened it's pressure would be directly on the sprocket and in turn the collar and bearing, i'm sorry to be a bit long winded but I want to give as much info as possible in the hope that someone can help because i'm at a loss, by the way Dave at Z-power measured a collar for me at 23mm which is 1.25mm longer than mine that 1.25mm would be a help but it would still be too close for comfort.
Steve

[Rich]

"when the nut is tightened it's pressure would be directly on the sprocket and in turn the collar and bearing,"

That is what should happen. the nut is tightened onto the tab washer which tightens onto the sprocket which tightens onto the spacer which tightens onto the inner bearing race which tightens onto the output shaft locking the whole tight so there is no play in it. The outer race of the bearing is held in place in the crankcase by a positioning ring.

If you are worried about it put a 1mm washer under the sprocket, but all my cases with the exception of my "best" one (which is in my spares box!!) have the raised bit worn down by the chain. If you want a sprocket with 6mm offset get a GPZ750a (JTF514) but you will have to space the rear out and check the clearance between the shocks as well

[Steve Cooke]

Thanks Rich, It's reassuring to know that it is not uncommon to rub slightly, I think I will fit a 1 or 1 1/2mm washer( if I can find one) it shouldn't affect the alignment any as it will probably just make up for the bit of wear on the collar.
fingers crossed, Steve