My bike's frameset has IS mounts. The mounts are 9.6mm thick. I bought a pair of IS to post mount adapters but they don't come with bolts. The adapters are 11mm thick. How long should the bolts be?
The adapters I bought are not Shimano but I saw that Shimano adapters (SM-MA-F180P/S, SM-MA-R160P/S) come with bolts 18.7mm long. Now I'm not sure how thick their adapters are. Are the bolts supposed to thread past the adapter or just short of it? Shimano also has those snap rings; are those needed or just the bolts and washers?