Bosch Gen 4 Lock Ring

[Nautical Biker]

I have recently replaced the chainring on my Trek Rail and noted that there was no rubber O ring fitted between the lock ring nut and the chain ring. I believe there is supposed to be one. The chain ring was a SRAM type, which I have replaced with a KMC. I just refitted the nut and torqued it up. Does anyone know of the O ring is required or optional? I note that E-Thirteen recommends not fitting one at all.

 

[irie]

Chain ring Line??

Looking to overhaul my drive line on my now 2 year old Sam 6.9. Got nearly all the components except the chain ring, looking at buying a Race Face one from Fox Australia as only one I can find but there is a section for chain line in mm's, one is 52mm and the other is 55mm's. Anyone know what...

www.emtbforums.com

Follow this ^^^ link

 

[Stihldog]

Sometimes, rather than a rubber “o” ring there is a brass one. I believe that this behaves like a spacer when used with the thin plastic “o” ring.

When I installed the ethirteen chainring I only needed the thin plastic “O” ring. Also, the castle nut, or retaining nut, can become stretched, deformed or damaged during removal and replacement. Some say that a small amount of blue Lo-tight is helpful to prevent loosening of the chainring. That may not be necessary if a new nut is used.

 

[irie]

I used a "belt and braces" approach: new castle nut torqued to the 35Nm marked on it + no O-ring + medium thread locker + tell tales. Nothing come loose since last June.