Can we spare 1/8" ?



Hi All,

I am working on making a dual pattern sprocket for use on our bikes (For those of you who may not know me I am part of the King's Sales & Service Group...sponsor on the left side of this page)...By dual pattern I mean the ability to use the sprocket with standard 9 hole mounting system that comes with the majority of our kits AND the ability to bolt the same sprocket directly onto a disc brake hub in place of the disc (you can read other posts concerning the advantages of being able to directly bolt the sprocket to the hub).

Anyways, the only potential problem of this dual pattern is that the large center hole would have to be reduced by about 1/8 " to allow for enough "beef" to be around the bolt holes of the smaller 6 hole bolt pattern.

The advantages of the smaller hole ...assuming that it would still fit for the 9 hole users... is that the center hole could be even more self centering and result in a more perfectly mounted sprocket for 9 hole sprocket users....Of course if the hole is a tad too may bottom out earlier on the hub and not allow the sprocket to mount on some hubs without the end user "opening" the hole up a tad.....not a real difficult thing to do but generally best if the end user did not have to modify anything....

NOTE: It may yet be better still if in fact the center hole does clamp tightly around the center of the hub unless it stops too far out?? Any ideas on this?

With that in mind...

I have gone to a few bike stores and a few department stores to see if we had the room to play with but of course I have only been able to measure a
limited number.....(in all the bikes I looked at the 1/8 could be spared...i.e. the center hole could be closed up with no ill effects on the standard 9 hole mount).... BUT I would like additional input form members and guests here to see if your center sprocket hole could be reduced by 1/8 and still fit where it needs to go.

Thanks in advance for any and all help.

1/8 smaller hole would fit on my hub (7speed cassette)
it would help center it better too I believe
sounds like a good idea to go with the dual mount !!!
Thanks for the input....I now have the info needed to make a dual bolt pattern sprocket.
a little late...yes, i could have (just barely) gotten by without the 1/8", if that helps any.