rwalters profile

Agreed. I've been at this so long, I don't even think about it. I don't stop spinning the pedals, but I let off just barely enough to give the chain a bit of slack.

I understand executing the "worst case scenario" when doing a product review - but do people actually shift gears while under drive load?? Am I the only one who religiously lets off the gas before shifting gears? I mean, the amount of time required is literally less than a second, and I've never thought to myself "I really wish I could continue pedaling through this shift."

I also just recently replaced my 5-year-old 11-speed cassette, so maybe I'm onto something?

Never, ever doubt the importance of good tires - especially for us riders in the PNW. Sticky tires make all the difference on wet roots and rocks, and can literally mean the difference between charging into a section, and getting off the bike and walking it. I never thought too much about tires, until I started trying different brands and compounds.

Posted by: RAHrider

Posted by: Sethimus

Posted by: RAHrider

I wasn't too keen on inserts until a friend of mine tried cushcore and told me that he liked them so much that if he had to give up something on his bike, the dropper would go before his inserts. I put off buying the $250 experiment for a month or two but after reading more, took the plunge. 

These stupid inserts are going to cost me a fortune by the time I upgrade all my bikes! They are so good I think I like The ride of my hardtail that has them better than my full sus without. 

So this thread is for people to sing the praises of cushcore and bemoan the cost. I have to say cushcore made my bike ride the way I've been trying to tune my suspension to feel for a decade!

do i need these on my gravel bike?

Probably for the gravel bike? 

In regards to the weight, before cc I kept getting Heavier and heavier tires for the sidewall support, not the traction. I think I am going to try lighter tires with the cushcore as I suspect this will still ride well. When you are running 2.5 Dd minions, it's pretty easy to find a 250 g lighter tire with equivalent traction. The lighter sidewalls will have far less rolling resistance and the bike will be the same weight with less rolling resistance. That's the theory at least....

Not sure why your friend tore out the cushcore on the trail. It's rare you can't plug a hole on the trail and it not, just ride the flat home. That's what cc is for.

For the record, I've been running EXO sidewalls with CC's for the better part of a year now with zero issues (and zero flats - knocks on wood). There is no way I could get away with EXO sidewalls without the CC's. For the most part, the CC hype is real. They do everything they claim to do. I sometimes have a hard time reconciling the weight penalty, but I would pretty much be running DH casings otherwise, so it's probably pretty close weight either way(?)

Also, after doing the install/removal a couple times, it's not that hard - so long as you have a really good set of tire levers and a trash can to support the wheel (as per the CC video). I carry a good assortment of tire plugs on my rides, in case of a flat, as I don't think I have the mental or physical strength to attempt a trailside removal of these things!

I personally didn't change my suspension settings at all when I installed cush cores.

Posted by: Znarf

@TAZ123: A tad less lowspeed compression, maybe a tad less rebound. Tire pressure and suspension settings are a tricky problem however.

In my experience, lowish tire pressure feels great for certain types of bumps - it carpets small chatter and hits. The same pressure (with inserts and no snakebites therefore) ridden in rough, rocky conditions can induce severe armpump.

Like with suspension, if you are too far into the travel most of the time and just riding along (too much sag maybe wrong suspension curve) you’ll run into the ramp up too much of the time and therefore the energy will not be dissipated in an even manner, but feel spikey to your arms and body.

Too high a tire pressure will let you bounce and struggle and make you tired fast, too.

Key in reducing rider fatigue seems to be a fitting ratio between the suspension curve of the tire AND the suspension AND the riders strength and dexterity regarding muscles.

Inserts can help with that, because they keep the tire from blowing through their „travel“ (which amounts to a couple of centimeters on a 2.4 tire...). Similar to a short tavel bike which is ridden really hard - with proper suspension settings it won’t be plush, but rideable.

Rim/wheel compliance can have a severe effect under these circumstances, too.

I can reproduce a loud clanging, tire to rim „bang“ event on my front wheel with a stiff 28h Newmen rim on a trail I ride often, but don‘t get the same BANG on either a DT Swiss EX1501 front wheel nor on a Notubes Flow MK3. Same bike, same tire, same pressure, same settings. Just the front wheel is swapped. No inserts. Minion DHF 2.5 WT @21PSI.

I want to nerd out (like you can tell from this post) and verify and reevaluate my findings with a FCK-Flats tire insert in the front tire. What will feel better? Compliant rim without insert or stiff rim with insert?

My (weak-sauce) wrists like extra chunky ESi grips (to filter small stuff) with not too low a tire pressure, firmer but still plush fork and single ply tires with big volume best.

And regarding tubes - I find ride quality AND ease of maintenance AND reliability of a proper tubeless setup is NEXT level compared to tubes. There are certain steps to follow to avoid hassle, for sure. But riding a proper mountain bike with tubes is leaving a lot of performance untouched. If your body can take the punishment of 40PSI and you are happy with the performance - all good for you!

Very well said. The difference between a given tire with and without inserts is much like an air sprung fork with and without bottomless tokens - tire inserts and tokens accomplish some of the same things. Tire insert allows you to run lower pressures, allowing more suppleness "off the top" (better traction, comfortable ride). A hard hit causes the air pressure inside the tire to ramp up quicker than in a tire without inserts. Of course, the insert isn't solid plastic, it's closed-cell foam, so there is some compression going on in the insert itself. Definitely takes some trial and error to get your settings right, but well worth it.

I don't know how you can run 40psi on a mountain bike. You definitely can't get away with that kind of thing with the conditions here. Inserts are definitely a pain in the ass to install, but after you've done the process once, it's a lot easier the next time. I'm running carbon rims and I feel a lot better rallying down chunder with the cush cores in. I once accidentally did an entire ride with ~17psi in the tires, and it was fine.

I think if you ride aggressively on savage trails, inserts make sense. I've had them on for a few months, and am sticking with them. And yeah - zero flats so far (knocks on wood). The only real downside that I've found is that your tire pressures will fluctuate much more with temperature changes. I think it's because the inserts greatly reduce the actual air volume in the tire. Starting on a cold morning at around 22psi, I've seen my tires get noticeably stiffer as the temperature increases.

I'm running cush cores, and have resigned myself to the fact that I'm never going to be able to remove/install a tire trailside. It's hard enough to do with proper tools and a garbage can at home. I do carry a decent selection of bacon strips and tire patches, but I don't even bother carrying a tube anymore - no point. And I'm not going to jinx my record by stating the number of flats I've had while running said inserts!! ;)

Yeah, I think that going with a different damper will be a last resort option for me, mainly due to expense. Going to shoot an email to fluid function and see if they have any ideas.

Anyone out there have any tips for setting up a newer generation Boxxer RC with 180mm travel? Most of the info I've found online applies to the 200mm versions, and the 200mm versions seem to get glowing reviews with rather simple setups (mind you, these reviews were all for the world cup version, the main difference being the Charger RC2 damper). I'm mainly having trouble getting the air spring right. My fork has a Charger RC damper and a Debonair 180mm spring. And yes, this Boxxer is mounted on an enduro bike. And yes, the same Boxxer that's not playing nicely with car racks!

A bit of back story: I'm coming off an older 180mm RCT3 Lyrik that also had a Debonair spring upgrade. That fork had the best spring I've ever used, but I hated the flex and creaky crowns. My settings in the Lyrik air spring were 2 tokens and about 78psi. I weigh 185 lbs. These settings gave me a decently supple initial stroke, great mid stroke support, and enough bottom out to resist all but the nastiest hits.

I picked up this Boxxer thinking it would be the same story, in a stiffer, burlier package, but I'm finding it really difficult to get the spring rate right. No matter what I do, the fork just feels way too linear. I started out with 3 tokens and 130psi. I found these settings pretty harsh off the top, and was still way too easy to bottom the fork out (too linear). After some experimentation, I'm now at 6 tokens (Rockshox says 6 is the max allowed - more on that later) and 130psi. Fork is still pretty harsh off the top, and resists bottoming a bit better, but still feels very linear to me. I am still bottoming the fork far more often than my old Lyrik.

Anyone have any ideas? Are my settings totally whack? People seem to love the WC model, so I wonder what I'm doing wrong. I'm wondering if running this fork at 180mm travel has taken it out of it's optimal operating scenario (even though the 180mm travel kit is a SRAM supplied part). I don't think it's the damper that's letting me down - I typically run my compression damping fairly open anyway.

One test I read on the WC had the settings at 2 tokens and 150psi, but I feel like this is going to be a super harsh initial stroke, and still too easy to bottom. Of course this test was at 200mm travel, so I'm not sure how that affects things.

On bottomless tokens: I have noticed that the spring side has room for more than 6 tokens. I'm not sure how many you could get in there, but it definitely has room for way more than 6 at full bottom out. My guess is the 6 token max. has more to do with max air pressure buildup than the physical room for the tokens. Worst case design scenario for this fork (according to Rockshox) is 6 tokens and 200psi. I feel like maybe I could get away with 7 or 8 tokens if I'm keeping the pressure around 120psi(??)

Any tips or suggestions would be greatly appreciated! I just really want to copy the feeling of the Lyrik air spring.

Cheers!

Update: NSR was able to adjust the cradle enough to make my bike fit.

Posted by: Xorrox

Posted by: rwalters

^^^ Nearly all of those ideas were achieved with my setup in the picture above! ;)

Okay, spill the details, you can't just leave us hanging! ;)

- How much travel? A-C measurement?

- As asked above, air or coil?

- What parts / custom work is required?

- Did you do it yourself or did you have someone do it for you?

- What adapter did you use for the headset?

- Are you running a 20mm downhill hub and axle or some kind of adapter?

- Ride impressions versus single crown - was it worth it?

Soooo many questions!

I dropped the travel to 180mm. Any Boxxer from 2019 and later can have the travel dropped to 190 or 180, you just need to order a new spring shaft from Rockshox (they're cheap). Fork is air spring (I think all new Boxxers are now air spring). Did the conversion myself - pretty easy. Used the same headset, just needed to get a different lower crown race to account for the smaller diameter of the steerer tube at the bottom (again, parts are readily available).

I don't know the fork length off the top of my head, but when I was researching this, the Boxxer set to 180mm is actually shorter than the 180mm Lyrik (by a mm or two). The Boxxer lower crown is quite low profile compared to the Lyrik crown, so I'd say this is the main reason the Boxxer is shorter. That said, you have a fair amount of adjustment with moving the stanchions in the crowns. My bike is now sitting a tiny bit lower in the front compared to when I had a 180mm Lyrik. I measured my head angle to be 64*. I believe the offset I had on my Lyrik was 39mm, and the Boxxer is 46 - so my front wheel is kicked out a little bit.

I was building up new wheels anyway, so I'm using a proper 20mm front hub.

Ride impressions: I've taken it out a few times now. Right off the bat - this is a completely new bike to me. The Nobl TR38's combined with the Boxxer make for an ultra-precise ride. It's a pretty wild feeling - I need to relearn how to ride this bike, and in a good way. You don't realize just how flexy a 180mm travel single crown is until you replace it with a dual crown. I don't think this setup will be for everyone though - you really need to ride aggressively to bring this bike to life. It will be overkill for most riders, but I'm tired of creaky CSU's and flexy forks. I ride pretty hard, so this made the most sense to me. I'm still in the process of getting the spring rate right - it's proven a little more challenging than setting up the Lyrik. I think part of that is I've taken a fork that is optimally run at 200mm and lowered the travel. There's not a lot of info on recommended settings at 180mm. I'm currently running the fork at 125psi and 6 tokens (Rockshox claims 6 tokens is max). 

Weight gain was very minimal. Fork is a bit heavier, but you lose a bit of weight with a lighter stem, shorter steerer tube and one less brake adaptor. I should weigh the bike, but I don't really care too much. 

As far as climbing goes, I've had zero moments so far where the bump stops prevented me from making a corner. In fact, I've found them to be a bit of help when you're really tired and negotiating a tight corner while climbing - you can rest on the bump stop as you make the turn. Laziness FTW!

Biggest drawback so far has been the fact that the bike didn't fit into my stock NSR-4 rack. I think this is mostly due to the new lower Boxxer crown. It's quite a bit different than previous versions. I was able to take my rack into NSR and they made some mods to the cradles that allowed the bike to fit. Joe at NSR was super helpful and is now aware of the issue - maybe this will lead to a design change to allow for the new Boxxer.

Overall, so far I'm loving the new setup. It hasn't gone quite as smoothly as I had hoped (my main issue at the moment is getting the spring rate right. Not quite there yet, but still experimenting. I am also looking around for a more vertically compliant bar - I'm basically running the stiffest front end possible on a trail bike, and it's making my wrists a bit sore after rides. Might look into the OneUp bar).

Any other questions, just ask!

^^^ Nearly all of those ideas were achieved with my setup in the picture above! ;)