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Discussion Starter · #1 ·
I've been out for just one ride on my 2017 Firebird and I've already got a badly scraped up finish on the back of the seat-tube where it meets the lower pivot link.

It seems that the design of this frame is going to be a problem here. The link leaves maybe 3mm or so (I didn't actually measure it) of clearance between it and the seat-tube and as you can see by the picture, there's a perfect little valley there between the two for small rocks to get caught, which they do. As the suspension moves through it's travel, these rocks are scraped up by the link along the back of the seat-tube. Without trying to rig up some sort of shielding here, it seems that the carbon is just going to get torn up in the path of the link.

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I come from a history of VPP bikes so this is new to me. Is this a common issue with DW-Link pivots? I'm kinda hoping it is so that there may be a known solution for this already out there. If anyone knows of some fix for this, I'm all ears. I've thought about, at the very least, trying to lubricate (maybe some teflon coating?) the area that is now scraped up in hopes of preventing further damage.

Thanks in advance!
 

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Same think happened with the Mach 6. I put lizard skin patches on that area before I rode the bike. 3yrs later the patches are chewed up a bit, but the paint under them is perfect. I'll throw fresh patches on this winter when I service the rear suspension.

Depending on how much space there is between the linkage and the frame in that area on the FB you could stack patches to fill it so that nothing that could really do any damage has room to get stuck in there.



I would also Shelter Tape other critical spots now while the bike is new. A few bucks spent on protective tape can save a whole lot of heartache and missed riding. My bike has shrugged off some hits in areas that I taped that would have at the very least made me sad and dropped the resale value of the frame should I ever choose to sell it.

Enjoy the new bike. :):thumbsup:
 

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Discussion Starter · #3 ·
Thanks, Vik. Yeah, I think taping it would be a good idea. I usually use door sill guard tape on other critical areas but never thought about this area between the links. I think I may swing by Home Depot and look for something weather-proof, sticky and low-friction. My hope with a low-friction surface is that the rocks can glide across more easily. It seems like this would be a good area for Pivot to add some sort of metal guard or coating similar to what you find on most bikes at the outside of the chainstay where it starts to meet the seat-tube to protect from chain slap (which this bike has as well).
 

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my wreckoning has a similar issue they are making the carbon tubes thicker and rocks can get in and scratch the bike. not being a carbon engineer I don't know if it affects strength but it kinda stinks to have the scratches.


I also think if you don't mind black gorilla tape works really well, that stuck is protective and sticks really well.
 

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Discussion Starter · #7 ·
Yeah, I'm probably just being overly anal about it. Hard not to when the bike is shiny and new (okay, maybe pretty dirty already, but shiny and new under all of that). I bought some foil sealing tape and some fine sandpaper to sand down the rough spots already created. I'm going to smooth it out and put the foil tape down on top, hoping that the lower friction of the foil will allow sharper rocks to slide up with less drag.
 

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Grand Master Jedi
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Perhaps fill in the area of concern with some foam rubber? Something flexible to fill the gap so that rocks can't get in there..? I'd also look at some adhesive-backed Teflon sheet to fill in the space or cover the top of the link so rocks can't sit on top. I'd be pissed if this was my frame! Seems like a poor design...


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Pivotal figure
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I've seen guys use a variety of things to try and keep that area clear and they've all ended up not working out. The wear tape is the best solution I've seen, any kind of boot just works to hold more material in the gap and lead to more abrasion.
 

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Discussion Starter · #12 ·
I ended up going with some foil sealing tape. Seems low-friction enough to hopefully prevent jagged edges from digging into it. I just wish I knew about this ahead or that some simple form of protection were pre-applied here. I realize I can't realistically keep a bike like this pristine but it's tougher to swallow damage done as some side-effect vs. action on the trail.
 

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Elitest thrill junkie
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It must be fine, otherwise Pivot would have protected it with a boot or some other device. They should warranty it if you get a rock jammed in there.
 

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Discussion Starter · #16 ·
I've put some foil tape on there but the foil tape has been gouged up by the problem still existing. I have a new idea though: I'm going to try and cut a piece of .019" thick aluminum sheeting and shape it to cover that section. Anyone know what would be a good adhesive to bond aluminum to carbon fiber?
 

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Anyone know what would be a good adhesive to bond aluminum to carbon fiber?
Unless you are taking off all the finish you are bonding to paint. I would just use Shoe Goo or something like that. More than enough adhesion and it's not permanent should you wish to take it off again.

I'll just note again I used $1 of Lizard Skin patches 3yrs ago and solved the problem. I'll spend another $1 this fall and be good for a few more years. Just saying...
 

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I've put some foil tape on there but the foil tape has been gouged up by the problem still existing. I have a new idea though: I'm going to try and cut a piece of .019" thick aluminum sheeting and shape it to cover that section. Anyone know what would be a good adhesive to bond aluminum to carbon fiber?
dude that's way to much. just put some lizard skin tape on and call it good
 

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Discussion Starter · #19 ·
Okay, maybe you guys are right so I'll give the patches a try. My theory around all this was to mostly eliminate friction around this area but, in truth, the link setup doesn't look very different thank Vik's pictures.
 
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