Z1-B Front sprocket spacer

[steve452]

I've bought an RK Takasago 630GSV XW-Ring drive chain which will be matched with a JTF518.15 front sprocket. On the original set up the front sprocket had a raised section which I believe went inboard to allow for the wider chain fitted to the B's. Interestingly enough, the old worn sprocket which came off my Z1-B had a flat surface both sides. The new sprocket is also flat on both sides. I've seen sprocket spacers advertised on fleabay so do I need one or more? Is there a way of calculating the width of spacer(s) required to get the chain in line and avoid chafing against anything?

Any advice on this very appreciated as I've come to a bit of a pause with this.

[Zedorset]

Wasn’t there a pin that went through the shaft that fitted in a groove on the back of the sprocket which stopped the sprocket from moving laterally on the shaft. Part number 92043-089

[steve452]

I believe the pin was to drive the chain oil pump so was redundant on a Z1-B.

If anyone can help with the original question regarding necessity of an inboard spacer to replace the effect of the bossed sprocket I would be eternally grateful.

[z2.john]

Rear sprocket spacer is 1.6 thick. You therefore need same for front

[CAT3]

The best thing to do is to put a straight edge across the rear sprocket & see how that sprocket aligns with the engine sprocket. That will tell you if & how much either sprocket may need spacing & which way.
This will be easier too without the chain being fitted.