cybrsrce AM831 build

[hagerd]

There is a good chance it wouldn't hit with the race that came with the Hellbender but I figured the +3mm would be fine anyway.

Hey Cybrsrce, did you use a 3mm crown race spacer on the zeb? what part did you use here to get the 3mm spacing?

[cybrsrce]

Hey Cybrsrce, did you use a 3mm crown race spacer on the zeb? what part did you use here to get the 3mm spacing?

Yes, Cane Creek part #840226125558 but it is also meant for a 36x45 bearing.  It won't be quite right with the supplied 45x45 bearing.

[FullCarbonAlchemist]

It felt acceptable at the ~20mm flex in the video and now if feels like roughly half that.  I haven't had it out on the trail yet but I assume it will be even more predictable.     

I got these M18x27mmx1mm - https://www.amazon.com/gp/product/B07NRXPYDG but I might experiment more.  The bolts are M16 (I think) and then ~2mm x ~2mm unthreaded surface to sit on the bearing.  I might try two of the M18 washers (cut to the size of the bolt head) and one or two M16 on the surface that touches the bearing to make sure there is good contact.

I do have the new shock in, first ride with it wasn't great.  Way too harsh even after I let it sag to 35% with rebound full slow and LSC open (full soft). Fork and shock recommended PSI, rebound, LSC, and fork HSC have all been way off for me.  Removed two tokens from the fork, one token from the shock, and added the MegNeg with a single band.  That seems to be what most of my near-clyde brethren are doing so I'll check that out.  Going to borrow a ShockWiz to speed this along.

I'll add some pictures of the bolt/washer combo and maybe a new flex video with it on the turbo trainer.

What is the damping tune? If it’s stock aftermarket Medium then it’s probably over-damped. The closest comparable tune (2018-2021 SC Bronson) is Low/Low with 2.5 tokens in the positive chamber, not sure about negative spacers if any.

Of course lots of people aren’t super happy with the stock tune on SC bikes but it seems like a good starting point.

[cybrsrce]

What is the damping tune? If it’s stock aftermarket Medium then it’s probably over-damped. The closest comparable tune (2018-2021 SC Bronson) is Low/Low with 2.5 tokens in the positive chamber, not sure about negative spacers if any.

Of course lots of people aren’t super happy with the stock tune on SC bikes but it seems like a good starting point.

The Super Deluxe Ultimate for HT v2 that I got was a L/L tune but it had internal issues.  I though it was me causing problems with a damper swap to the standard body but Rockshox replaced it.  I ended up returning the replacement and getting a standard M/M tune version.  Two tokens and two bands and it is alright, I'm going to try three tokens and 3-4 bands.  Keep it under 300psi and should get full travel.

Everyone complaining on Youtube says the stock L/L tune doesn't have enough mid support but the M/M seems to have too much, at least at high PSI.   

[FullCarbonAlchemist]

The Super Deluxe Ultimate for HT v2 that I got was a L/L tune but it had internal issues.  I though it was me causing problems with a damper swap to the standard body but Rockshox replaced it.  I ended up returning the replacement and getting a standard M/M tune version.  Two tokens and two bands and it is alright, I'm going to try three tokens and 3-4 bands.  Keep it under 300psi and should get full travel.

Everyone complaining on Youtube says the stock L/L tune doesn't have enough mid support but the M/M seems to have too much, at least at high PSI.

Yeah, that’s why I fell in love with the DVO Topaz stock tune….it’s at least as supple and willing to use travel as a Fox/RS low tune but more supportive, and the support can be tuned a bit more independently from bump absorption than other shocks.

It helped me with my GT Force that has shipped with both Medium and Low tunes, and from what I understand was specifically intended to address the issues people had with Santa Cruz VPP bikes. They’ve branched out since then, but in the early days a lot of the principal guys at DVO like Ronnie rode SCs.

It’s too bad that pump hose fit for the piggyback is probably an issue with DVO and Suntour TriAir shocks on the 831. I bet either one would work well otherwise, as stock aftermarket tunes go.

Hopefully by the time the upper swingarm pivot issue with the 831 is confirmed to be properly sorted in current frames going out, the second gen Topaz T3 will be shipping with that sideways piggyback.

[scourge]

The stl files for the different washers attached should anyone want them.  My old printer didn't like them all arranged in the stl so I had to add them individually for some reason.

So does anyone here  have easy access to a 3D printer? I asked all my friends and no one has access to one. I'd like to try these out to see if it helps with the flex on my frame.

If someone has access to one and is willing to print out a set, send me a private message. Should be able to just drop them in an envelope to ship them.I'll be happy to pay for them.

[hagerd]

So does anyone here  have easy access to a 3D printer? I asked all my friends and no one has access to one. I'd like to try these out to see if it helps with the flex on my frame.

If someone has access to one and is willing to print out a set, send me a private message. Should be able to just drop them in an envelope to ship them.I'll be happy to pay for them.

If you shop it out, it may be worth getting these printed in nylon for the lower friction factor.

[Maffly]

I ended up cutting my own nylon washer to fit despite having access to 3D printer.  Determined with my friend who is a mechanical engineer in fabrication and production that the nylon is better for this application than the material that would be used in the 3D printer.  We are going to order nylon washers in the exact measurements from a company he sources from. The spacers are going to have to serve as bushings because of a design flaw with this frame. If there is not pressure on the carbon pushing the bearings on to the upper link, you are relying on the strength of the bearings bond with the upper link to provide stability (not good). Because you need pressure on the carbon of the upper link and this link needs to pivot, it is essential in order to prevent wear and to not bind the suspension that the material used can be low friction.  I think if the bearings were pressed from the outside, this frame would work very well.

[cybrsrce]

I ended up cutting my own nylon washer to fit despite having access to 3D printer.  Determined with my friend who is a mechanical engineer in fabrication and production that the nylon is better for this application than the material that would be used in the 3D printer.  We are going to order nylon washers in the exact measurements from a company he sources from. The spacers are going to have to serve as bushings because of a design flaw with this frame. If there is not pressure on the carbon pushing the bearings on to the upper link, you are relying on the strength of the bearings bond with the upper link to provide stability (not good). Because you need pressure on the carbon of the upper link and this link needs to pivot, it is essential in order to prevent wear and to not bind the suspension that the material used can be low friction.  I think if the bearings were pressed from the outside, this frame would work very well.

I understand the concept that you're talking about here but how does putting a crush material between the bolt and carbon differ than just the bolt on carbon in a correct layup for friction?  I get that it is a flawed design but I don't see how the material would make much of a difference here as long as it maintains structure.  In a perfect world it would be bolt -> bearing -> carbon -> bearing in linkage or something like that where no portion is restricting movement. 

Also - The one off costs from someone like shapeways to "print" in nylon is like $50 for a set so cutting your own out of a bag of 100 for $6 isn't the worst way to go. 

[hagerd]

The difference is the face of the bolt would be up against a wear component (nylon washer) with a lower coefficient of friction. Ideally there would be a thrust bearing here but a bushing is close enough.

[Maffly]

100 percent correct. I actually had some perfect sizes aluminum spacers off of a Evil suspension rebuild that I put in there. Rear end stiff as a board but suspension noticeably impaired movement. Also some wear in carbon evident (like a light sanding)after just bouncing it around for a bit.

[Maffly]

Also Cybrsrce, because we are looking to get structural support from the pressure on the carbon, I skipped the inner spacers that would contact the bearings as that would just maintain the faulty proportions 

[cybrsrce]

Again though, the bolts are also an alloy and would be metal on carbon if there wasn't a play issue.  That said, PLA, ABS, Nylon, etc. really shouldn't make a different as their friction coefficient is going to be better than alloy on carbon that you get from a normally "functional" triangle.

At the end of the day, are we making out better?  

[cybrsrce]

Also Cybrsrce, because we are looking to get structural support from the pressure on the carbon, I skipped the inner spacers that would contact the bearings as that would just maintain the faulty proportions

Without that I do not get contact with the bearing.  That would be a good spot for a metal washer though.

[hagerd]

Just to add, I would also grease the hell of out this joint and make it  part of routine maintenance.