New 530 conversion sprocket doesnt seem right?

[liloaty]

I am trying to convert my 1980 GS1100E from a 630 to a 530 chain. I had the guy at the local shop order me the parts, and its a SunStar front sprocket, part number 51115. According to SunStars web site, this is the correct sprocket for my application. However, it seems to have 2 screw holes, 180 degrees apart and a smaller hole about a third of the way between the others. My current front sprocket, and as far as I can tell from schematics, the OEM kind, has three screw holes 120 degrees apart. I dont see how this can be correct, am I missing something obvious? Any help would be appreciated, thanks,

[Hap Call]

I am trying to convert my 1980 GS1100E from a 630 to a 530 chain. I had the guy at the local shop order me the parts, and its a SunStar front sprocket, part number 51115. According to SunStars web site, this is the correct sprocket for my application. However, it seems to have 2 screw holes, 180 degrees apart and a smaller hole about a third of the way between the others. My current front sprocket, and as far as I can tell from schematics, the OEM kind, has three screw holes 120 degrees apart. I dont see how this can be correct, am I missing something obvious? Any help would be appreciated, thanks,

The screw holes should not make any difference. What counts is that you have the .24" spacer on the correct side of the front sprocket, that the sprocket nut is torqued tight enough, and that you have the lock washer in place and securing the sprocket nut.

Hap

[chef1366]

On the E model you have a stock spacer on the inside of the sprocket. The replacement sprocket might not be wide enough to tighten the nut and lock washer down on the new sprocket. You might have to use the old noise reduction dampeners from the old sprocket for spacers.
On my L model it is on the inside of the sprocket. I had to take the noise dampener off the old sprocket and use half of it for a spacer because my bike did not come with a lock washer and I felt I needed one after I lost the sprocket nut twice and I was stranded. I didn't "lose" the nut because it got stuck in my sludge of chain wax. \\/

[liloaty]

Thanks for the reply guys. So the consensus is I need to use one, or possibly both, of the original noise dampers for spacers on the inside of the new sprocket? Thanks guys.

[DimitriT]

On my 750 I used the original inner cushion/spacer but went with a new spacer on the outer. The original outer wasn't a tight fit on the axle so it wouldn't work. I bought a spacer (6mm I think) as part of the conversion parts.

[liloaty]

OK, I will pick up a spacer today then. The original spacer goes on the inside, the new 6mm spacer goes on the outside. With these correct spacers, I wont need the OEM noise dampeners anymore. Is this all correct?

Thanks for all the help, I have been around bikes all my life but no chain drives :-(