Hi,
Installing a spider for Bosch Performance CX Gen4 sounds to be easy and a seek for help might stupid, but I have ran into some issues:
1) My framework is non boost, measures ~140mm on rear without wheel removed so it is 142mm non boost, as boost is 148mm. For my bike by the manufacture year also it is said to use non-boost spider. But non-boost spider does not fit and chainline moves 3mm inside (when the below mentioned spacers are removed. With the spacers there is not enough thread remaining for the lockring). Boost spider without spacers looks ok, chainline is same as on original installation of a chainring. Can someone explain this oddity?
This is how original chainring was mounted:
* Black 2.6mm spacer which went inside recess on the axle
* Silver 1mm spacer
* 3.2mm chainring
* lockring
As I understand I need to remove both of these spacers and install boost spider. Boost spider thickness is 5.6mm.
But the spider also has a small recess on the lockring side - do I need a spacer to go in it, or shall I add a lockring directly (basically spider + locking and nothing else).
In my understanding these spacers are needed as original chainring is steel and it being 3.2mm thick gives enough strength to grip on the axle. The spider is aluminum and is thicker, cause it needs more grip. So the spider also has that thickening on one side, so no spacers. Am I correct?
Thanks in advance.
Installing a spider for Bosch Performance CX Gen4 sounds to be easy and a seek for help might stupid, but I have ran into some issues:
1) My framework is non boost, measures ~140mm on rear without wheel removed so it is 142mm non boost, as boost is 148mm. For my bike by the manufacture year also it is said to use non-boost spider. But non-boost spider does not fit and chainline moves 3mm inside (when the below mentioned spacers are removed. With the spacers there is not enough thread remaining for the lockring). Boost spider without spacers looks ok, chainline is same as on original installation of a chainring. Can someone explain this oddity?
This is how original chainring was mounted:
* Black 2.6mm spacer which went inside recess on the axle
* Silver 1mm spacer
* 3.2mm chainring
* lockring
As I understand I need to remove both of these spacers and install boost spider. Boost spider thickness is 5.6mm.
But the spider also has a small recess on the lockring side - do I need a spacer to go in it, or shall I add a lockring directly (basically spider + locking and nothing else).
In my understanding these spacers are needed as original chainring is steel and it being 3.2mm thick gives enough strength to grip on the axle. The spider is aluminum and is thicker, cause it needs more grip. So the spider also has that thickening on one side, so no spacers. Am I correct?
Thanks in advance.
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