jbrown15
Well-known member
Sorry Rob, but I have to call you out on this post.
A properly designed carbon frame will be layed up into a cnc cut mould, all bearing housings and areas that require precision will be set by the mould. The layup variance , though critical to strength of the design should not effect bearing/pivot tolerances. In effect a properly designed carbon mould will be as accurate as cnc cut parts. You could make an arguement that carbons frames layed up in the same non changing mould will be more accurate than cnc machined parts over time as cnc machines experience tool wear and associated tolerance creep.
I'm just doing a full bearing replacement on my 2018 Rocky Mountain slayer suspension.
Ok I've had some challenges getting seized and grime packed beatings and bolts out.... that's my own fault for leaving it too long between maintenance intervals.
When I clean up the parts and press the bearings backing and reassemble the suspension everything fits like a glove.
The tolerances on that carbon frame are bang on....
I think what you experienced is some poor attention to detail to design tolerances for the carbon frame....
Ps, my day job Is designing and manufacturing. You can have a fantastic design but it can all turn to shit if you get the manufacturing tolerances wrong.... and or dont spend enough time and money on the tooling/jigging.
I work in a bike shop, in my experience Rob's observation is pretty accurate. Tolerances will vary from brand to brand and even batch to batch of bikes. It's not every time, but it's also not unusual. We'll do maintenance on the same model of bikes and the tolerances on the bearings can be quite different from the same model but a year or two apart in production.
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