[greyghost]

I just got a new bike with the 105 group. To save a whole bunch of money I get to assemble the bike myself. There is a significant grind when cassette in running on the 4 smallest cogs, and the grinding gets worse as the cogs get smaller. The top 5 cogs have no grinding. This is not a chain rub grinding, it is not hitting the front derailer. Also, the cogs appear to have a very slight wobble, but so does my other bike which does not grind.

My other bike is ultegra, so is the grinding just normal noise due to the lower class components? Also, I am pedalling it up on a trainer, so does having the bike hanging in the air accentuate the grinding? Or is it a screwed up cassette? Any help would be greatly appreciated.

 

[Dave Hickey]

I just got a new bike with the 105 group. To save a whole bunch of money I get to assemble the bike myself. There is a significant grind when cassette in running on the 4 smallest cogs, and the grinding gets worse as the cogs get smaller. The top 5 cogs have no grinding. This is not a chain rub grinding, it is not hitting the front derailer. Also, the cogs appear to have a very slight wobble, but so does my other bike which does not grind.

My other bike is ultegra, so is the grinding just normal noise due to the lower class components? Also, I am pedalling it up on a trainer, so does having the bike hanging in the air accentuate the grinding? Or is it a screwed up cassette? Any help would be greatly appreciated.

It sounds like the 9th cog is not on properly. Try removing the last cog and re-installing it. The wobble happens when the spines are not lined up correctly. The lock ring will still fit even if the last cog is not installed correctly.