Topic: Front sprocket wiggle - 750 78K - how much?

[fxef79]

Post 11 shows a thicker stock sprocket.

I've got a 17t (came on the doner K8 bike, which had been changed to 530 chain by a PO), a 16t (came on the 72/78 frankenstein engine that was in the trike), and a 15t (actually came from a 450)... and none of them have the thicker section. They're all completely flat.  Pic in post 11 is maxheadflow's.  Mine are shown in the later posts.  The 17t is pretty worn and I'm not going to use it, anyway.  For now I'm using the 16.  I've considered the 15, but only because the rear sprocket on this trike is a 37 tooth Servicar axle.  But I don't want to stress the 530 chain too much going around such a small sprocket.

[Alan F.]

This is the only good pic I can find of my K8 sprocket

Looks all original to me, sprocket is flat on this side.

[Alan F.]

My new (Bikemaster) 630 15t is flat on the front and has a shoulder on the back.

[754]

I dont know if the K7 and K8 sprockets were thicker. But earlier ones were.. and there was movement on early ones .
 Saying this because nthen running a thin one , would give more movement than intended.  .