cruzKurt
Guru
Emailed, support@cruzbike.com
Slider crack - maybe?
- Thread starter Midnight
- Start date
Hey all. This has been a thing we have seen on some of the early ones. I would ask you all to let us know in the service email so we can keep a list of folks needing a new slider and we are working on replacing these - and also getting more made currently. We have not found this to cause situations where the boom pushes out under power - which is the situation we don't want. So far I have not seen or heard of one doing that.
No matter what - rest assured all is getting taken care of - the early ones our manufacturer replaced and improved.
No matter what - rest assured all is getting taken care of - the early ones our manufacturer replaced and improved.
Rolling Along
Active Member
I already emailed support before reading this. My V20c was ordered on 9/3/23 (I included this and the order number). I thought this date was after the early ones. So what date is the cutoff of early ones?
I have used epoxy to make several boats and a composite truck camper, I suspect something like a West System Gflex resin would be more than enough. Looks like a cracked fillet, but I have no real knowledge of the construction. You would have to do some deconstruction to examine the crack and the construction method.
Midnight
Member
I did and now per his request to the email you listed above.
Thank you for helping out!
UPDATE - new slider on the way, I pay shipping for new and return of old since I am not the original purchaser.
Last edited:
Mathew Fy
GRU
I received and installed my replacement curved slider, so now to assess the potential for failure.
The slider is 2 mm thick all around and 2.35 mm at the crack area. The ridge I felt with my fingernail (on the inside) correlates with the outer crack. No propagation of the crack was apparent to me visibly until forcing the section apart. This caused the carbon fiber to separate from the fill section where the bolts press the metal thing against the boom.
The 3rd image below shows the outer crack appearing to extend into the middle, but that was only after prying apart. I feel confident in these sliders, but am glad was able to get a replacement so quickly.
The slider is 2 mm thick all around and 2.35 mm at the crack area. The ridge I felt with my fingernail (on the inside) correlates with the outer crack. No propagation of the crack was apparent to me visibly until forcing the section apart. This caused the carbon fiber to separate from the fill section where the bolts press the metal thing against the boom.
The 3rd image below shows the outer crack appearing to extend into the middle, but that was only after prying apart. I feel confident in these sliders, but am glad was able to get a replacement so quickly.
Attachments
Hey all - of course we never like to see this sort of thing, but know we are getting more reinforced sliders on the way... I have been having nightly conversations with our MFG partners so they are aware and also getting replacements in the pipeline. After looking at a few of these closely I don't see these as an imminent fail issue but as always we will make it right.
Robert
Robert
Are there plans to retrofit previously replaced sliders with the reinforced version? Why was 5nm torque chosen? It seems excessive. One 5mm screw at 5nm places about 509 kg or 1124 lb force on the joint. This design has two. There is also some redundancy, being that the clamp at the head tube also compresses the two together, providing some backup slider retention. I have been using 4nm since my replacement slider was received without any issues. This is the torque value where I felt things where starting to flex. I have also noticed that there is no visual gap (even at 4nm) between the slider and the screw head - which there should be if the design intent is to put the full force on the slider joint. So either the screw is too short or the inner tube of the assembly is flexing enough to remove the gap. Are there plans to also reinforce the inner tube of the assembly (not sure what the official name is for that part)?
Our manufacturing partner that makes the CF parts is making replacements as I type this - they are supposed to be stronger in that junction and we will likely go to the 4nm as the torque for that part as it seems to be sufficient.
Randyc3
Well-Known Member
Hi,
Same here. Maria, Robert Holler & crew responded quickly days before a big ride. Kudos to them for the support.
