[Random_Cyclist]

I’m not the most experienced MTBer around, and I lack many technical reference points (I have not ridden many different MTBs). Anyway, here are my views based on the entry-level hardtail I bought at the beginning of the 2019 season, especially about reliability, robustness after 3,000km on the bike

The bike is a basic Decathlon bike that came fully kitted out with SRAM/rockshox/truvativ components

. GX shifter: still works fine. No play. Feels as new with good indexing

. GX rear derailleur: has developped a lot of play around all pivot points, especially the derailleur cage. Clutch still works OK despite no maintenance. Indexing is still OK. Not smashed by chance, but overall design is design feels very cheap (i.e. plastic pulley and pulley support for cable alignment), and design does not allow for any repair. Overall, works well but should be considered a throw-away item. The much-cheaper Shimano Deore 10-speed derailleur on my touring bike is much better designed, engineered and built.

. Truvativ cranks: details on my opinion here: https://www.singletracks.com/blog/forums/topic/srams-bottom-bracket-preload-ring/ The cranks themselves are OK, and the chainring is not fully worn out after 1 season. But the design of the bearing preload ring (used on all modern SRAM cranks) is just plain awfull: Cheap self-tapping screw, and plastic ring to support all axial load. My conclusion: use Shimano

. NX cassette (11-50 on Shimano-style freehub body).  Setting the upper derailleur jokey wheel very close to the cassette give good shifting on the smaller cogs. Setting the upper derailleur jokey wheel very far form the cassette give surprisingly good shifting on the larger cogs. I was usrpised that the large jumps between cogs did not prevent good shifting. However, I was unable to get a good shifting at both ends of the cassette with the same b-tension setting. The NX has no/few ramps on the 6 smaller cogs despite the large jumps in gearing. My conclusion: It’s cheap for a reason

. RockShox Reba RL (32mm) fork: stiffness is pretty good (much better than the Fox 32 I tested. the smoothness is pretty good. No play has developped is the bushings over the season of use. The spring holds well the pressure over time. The rebound damper works well, though i only use it in its most open setting. The Motion Control damper (compression damper) didn’t work well from the start (details here: https://www.singletracks.com/blog/forums/topic/2019-rockshox-reba-rl-damper-upgrade-hack/) . The main valve in the compression damper has so much play/leakage that I have no hope that the damper could work consistently and reliably. My opinion: the fork overall is pretty good except for the Motion Control damper (fitted to most entry-level SRAM forks), which is hopeless. My conclusion: my next bike will be fully rigid

. SRAM Level T brakes. These are rebranded AVID Elixir. I understand that the Elixir were famous for their unreliability and inconsistent braking. From my experience the rebranded SRAM Level T are exactly the same. I wrote in the post here my first impression on those brakes: ” I clearly noticed a decrease in brake performance as I progressed in the descents, I suspect linked to the pads and discs warming up. Typically, after 500m-, I’d have to switch from 1-finger to 2-finger braking. And after 1,000m-, I got strong reminders of my cantilever brakes from previous bikes… More alarmingly, and even on the shorter descents, once every 20 or so braking, one of the brakes would fail to provide any kind of power. The lever would feel very spongy, and provide virtually no braking power. Then, the power would could back after a few minutes just as randomly as it disappeared. Anyway, my conclusion is to switch to 200mm rotor front and back, and Shimano 4-pot calipers (Saint or XT 8120). I had heard that SRAM brakes were hopeless (both local bike shops around me rent MTBs and sale them at the end of the season, and both shops told me that they’ve given up on SRAM brakes because they don’t survive a 3-month season on rental bikes)”. My conlusion: I won’t run again any SRAM brakes

Overall, based on my limited experience, I would say: Use Shimano, MicroShift, Tektro, Hope, and only as a last resort, consider SRAM is that’s all you can afford, but don’t expect it to last

[Random_Cyclist]

just decided to go with bar tape… I know, I’ve got “roady” habits.

The bar tape seems to me to be a good way to double-wrap over the position of the normal grips, wrap over the brake lever clamps, wrap all the way to the stem for a comfortable climbing position (similar to riding on the tops of a drop bar bike), and wrap my middle-mounted bar-ends (or bar-middles in this case).

And critically, bar tape is cheap, especially the foamy type, which I prefer.

[Random_Cyclist]

Hi Marco,

You could consider the reasonably-priced Décathlon RockRider XC 500. It comes in both 700c and 650b (both in plus and non-plus versions).

I rode the bike through Navad 1,000 in June, and it worked OK for the job. And because the bike is quite aggressively priced, you can consider upgrading the components you’re most sensitive about, or as they wear out and break:

• if you head for the mountains, you’ll definitely want to upgrade the basic (not to say hopeless) SRAM Level T brakes, an upgrade to 200mm rotors.
• if you’re going for a long bikepacking trip, Shimano-compatible cranks (BSA-threaded BB+ 24mm spindle) will be far more robust, durable, and easy-to-find-spares than the default Truvativ cranks (they come with a cheap plastic preload ring, and it’s all held in place by the world’s cheapest self-tapping screw – which results in inconsistent BB bearing preload and fast spindle wear)
• the tyres, as with most OEM XC-style builds, are paper-thin (often a way to save money and save a kilogram off of the bike weight). You’ll want to upgrade to double-ply or EXO casing tyres. And that’s where I’d recommend to go 700c (29″ if you live West of the North Atlantic) rather than 650b Plus. Most Plus tyres (650b Plus and 700c Plus) are very thin to keep their weight low. Unless you’re planning to ride very mellow trails, I’d go with normal width (50 to 65mm – 2″ to 2″1/2, which the Decathlon bike can accommodate) and reinforced sidewalls. Personally, I will even look into inserts, I can’t bear spending my life fixing punctures on the side on the road

– 27+ : possible, but I’d recommend 29″. it’s possible to buy a pack with both wheels sizes from Decathlon

– eyelet or possibility to mount a rear rack : stap, tape, there’ always a way

– bottle holder bosses on the downtube (optional): yes

– weight max 14kg: yes, even with the packs strapped on

– Dropouts alternators (optional): no

– European bike producer (optional): yes, it’s assembled in France (at least for the Western European shops)

The bike isn’t perfect, but I found it OK for bikepacking. And its reasonable price means you could upgrade later down the road.

[Random_Cyclist]

Thanks Vapidoscar for the pointer.

I spent last night geeking out on lots of component websites, and came to the realisation that it will be more cost-effective to buy a new bike rather than upgrade my RockRider XC 500

I bought the bike earlier this year. In approx 6 month, it’s completed 3,000 km and about 100,000m+, and I have to accept that it’s reached its end of life. It’s been a good bike, and got me through Navad 1,000 in less than 7 days. But Navad has tested the components to their limit:

• the rear wheel is taco’ed (I broke 2 spokes during the race, rode the last 200km of the race with the broken spokes. I fixed the spokes once home, but on further inspection, the rim is taco’ed beyond repair)
• The 32 and 36 tooth cogs of NX cassette are worn out (and require replacing the complete cassette)
• the GX rear derailleur still shifts OK-ish with a newly-fitted cable, but the cage has a lot of play
• the Rockshox Reba RL… see above. And I’m switching to a rigid fork anyway: 1kg saved on the bike and the added robustness (the compression damper on my Reba gave up working after 500km of race)  will outweigh the few seconds lost on the descents
•  The Rockrider 500xc 29″ is fitted with SRAM Level T (180 front, 160 back). The Navad 1,000 route included 5 or 6 long descents (over 1,500m-). I clearly noticed a decrease in brake performance as I progressed in the descents, I suspect linked to the pads and discs warming up. Typically, after 500m-, I’d have to switch from 1-finger to 2-finger braking. And after 1,000m-, I got strong reminders of my cantilever brakes from previous bikes… More alarmingly, and even on the shorter descents, once every 20 or so braking, one of the brakes would fail to provide any kind of power. The lever would feel very spongy, and provide virtually no braking power. Then, the power would could back after a few minutes just as randomly as it disappeared. Anyway, my conclusion is to switch to 200mm rotor front and back, and Shimano 4-pot calipers (Saint or XT 8120). I had heard that SRAM brakes were hopeless (both local bike shops around me rent MTBs and sale them at the end of the season, and both shops told me that they’ve given up on SRAM brakes because they don’t survive a 3-month season on rental bikes), now I can confirm based on my own experience that I won’t run again any SRAM brakes

So overall, that’s a lot of money to spend on a bike: changing the rear wheel is the chance to switch to Shimano MicroSpline and run away from SRAM… but the math adds up to a too big total. Rear wheel with MicroSpline hub (EUR 400), SLX cassette+shifter+derailleur (EUR 300), XT brake set +discs (EUR 400), ridig fork (EUR 500)… and the total already exceed the value of the bike when new.

So I guess I have to accept that the bike has serve me well so far, but I will upgrade the whole bike. The Orbea Alma M15 is indeed very tempting: it’s SRAM-free, and can be fittedd with Orbea’s Spirit rigid forks. I’ll geek out for a couple more days on OEM’s websites, reading through specs and geometries… but the Orbea Alma seems pretty much spot on for me.

 

[Random_Cyclist]

I’m giving up on the Rockshow Reba. The Motion Control damper is too unreliable for me. Over the past 5 months, I’ve spent 90% of the time with a non-functionning lock-out, and a changing level of compression damping.

My understanding is that the blue-anodised release valve on the compression damper has so much play that it rarely seats properly against the damper body.

After test-riding a bike with a Fox 32 fork, I’m not convinced either. The spring and damper felt much better than on the Reba, but I was massively disapointed by the super-flexy chassis.

So, I’ve decided to upgrade my bike to a rigid fork. I’m therfore looking for a rigid fork: approx. 480mm axle to crown, 51mm offset, 110mm boost spacing, aluminium or carbon, ideally compatible with 200mm rotors, clearance for 700x55c tyres, and the whole thing for a reasonable price, of course?

A bikepacking.com article lists quite a few options (https://bikepacking.com/index/forks-with-bottle-cage-mounts/), but nother under USD 500… I’m looking for a more cost-effective option. I’m happy to go with an aluminium fork. I’ll save close to a kilogram compared to the Reba RL, so I’m not to fussed about 50 or 100 additional grams of an Al-alloy fork.

Any recommendation?

[Random_Cyclist]

Thanks Sam, I’ve found a hack that makes the Reba RL works (ish): No impact on the ‘open’ compression damping, but at least the lock-up works as intended (almost fully locks-up after 3/4mm of travel).

I replaced the spring at the bottom of the compression damper assembly with a much stiffer spring (not quite the right dimensions, but it works). It’s the spring that maintain the blue-anodised valve closed during compression and open during rebound.

Compression damper assembly

Valve in open position (during rebound)

After a ride, the modification seems to works consistently. I’ll see over time if I try with a higher viscosity oil, but I’m concerned it would slow down too much the rebound damper.

For now, this will do the trick. I wish someone at Rockshox will read this post and apply the modification to the gazillion different versions of the Reba RLs, or at least offer a replacement spring for their exiting customers.

[Random_Cyclist]

Thanks Sam for your feedback.

I actually got a first bike delivered by Decathlon a few weeks ago. I thought the Lock-out was faulty, and got the bike exchanged (BTW, the Decathlon customer service was great and very easy to deal with to organise the swap).

A week later, I received a new bike. And the behaviour of the compression damper was exactly the same. I drove to my local Decathlon shop, and ‘pushed’ on the RockShox Reba RL they had in their inventory on similar bikes. Turns out, that none of the Reba RLs actually fully lock-up. They all felt ‘squishy’ when locked-out. And they all felt pretty inconsistent. That’s why I’m thinking of updating/hacking the compression damper myself.

I pulled out the compression damper out of my fork. Everything looks normal. In the unlocked position, the 2 holes in the compression damper line up (between the aluminium and the plastic part). In the spring-loaded locked position, the holes don’t line-up. The o-ring on the outside of the daper seems to seal well againt the fork leg.

My guess is that the leak between the aluminium and the plastic parts (the ones with the calibrated holes) is so large that the control of the oil flow is poor. I guess that more oil leaks between those 2 parts than through the 2 holes.

The rest of the fork works reasonnably well. And the fork is pleasantly rigid (especially compared to simalarly-priced Fox forks). So, I’m inclined to change the damper (either the compression damper, or the complete compression/rebound unit) for a higher spec model. But I don’t know which model will fit? Charger? Charger 2? Are they available for 29″ 100mm Rebas? and especially, which damper models actually offer a ‘real’ lock-out?

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