2021 Trek Domane AL 2

The 2021 Trek Domane AL 2 (rim-brake) is an entry-level endurance road bike with an alloy frame, carbon fork and endurance geometry.

It features Claris R2000 shifters and derailleurs for 2×8 gearing (50/34 chain rings, 11-32 cassette), Shimano RS200 cranks (175mm) and a UN300 bottom bracket (with 110mm spindle).

The stem is a 100mm Bontrager Elite (7 degree), the handlebars a Bontrager Comp VR-C with 100mm reach, 124mm drop and 44cm width. It rides on 17mm wide Bontrager rims (tubeless ready) paired with Formula QR hubs (100mm wide front, 130mm wide back using cup and cone bearings) and officially has clearance for up to 28mm wide tyres (although the previous owner had fitted some 32mm wide ones that cleared fine).

I purchased this bike second-hand in August 2026.

Modifications/Additions

  • Tyres
    • I have transferred over a set of Schwalbe Green Marathon tyres that were originally on my Pinnacle (before it got written off). They’re 28mm wide and have strong “GreenGuard” puncture protection. The Marathon range are noted for riding harshly and being a bit heavy as a consequence of having that level of puncture protection – I find the ride tolerable (the Pinnacle had an alloy fork, so the carbon fork on this bike gives a little more damping in comparison) and I prefer to have the lower puncture risk. Another downside of the robust construction of the Marathon series though is that they are a pig to fit/remove (even using the technique of strapping the opposite side of the tyre and using tyre levers), so if I did get a puncture it’s going to be hard work wrangling the tyre on/off so fingers crossed I can avoid that!
  • Mudguards (Fenders)
    • As my intention is to use the bike through winter it needed some mudguards. Although the frame has mounting points for mudguards clearance is tight through the fork with 28mm tyres on (Trek officially list 25mm as the max with their mudguards), especially with the thickness of the Green Marathon tyres. Looking at options for mudguards suitable for tight clearance and the Crud Road Racer Mk3 came up which have the added bonus of (theoretically) being relatively easy to remove/refit due to the “velcro” style fixings so I can keep them off during dry spells and refit if I need to ride on damp roads. They were a faff to fit – in theory the positioning of the strips stuck to the frame isn’t super sensitive as the corresponding fixings on the guards are much larger, however the Duotec fixings are a little like “stickle bricks” so rather than a truly continuous range of position it’s more like a fine grid of positioning that it snaps to, but you still have a fair range of adjustment you can do. This model of Domane has incredibly tight fork crown clearance (and the crown is curved) so the front was the most problematic to fit – although the front end of the main guard section narrows where it would pass under the crown it’s less curved than this bike’s crown so I basically had to trim some material off to get enough clearance. Past versions attach the little extra nose section for the front guard using adhesive tape but I think criticism of how strong that fixing is means they now supply a little bolt to match the rear – much stronger, but a downside is it can limit your fore-aft position of that part of the guard without fouling the brake calipers. As it happens though the bolt allowed me to get better clearance for the nose section – it was slightly skimming the tyre at one point and by adding a washer between the two parts I was able to get it to angle up slightly for better clearance. They include little circular foam pads to stick to the mudguard at any point it’s close/touching the frame to stop rattle noises (and protect the frame). I also added frame protection tape under the crown and around where the rear mudguard cable tie passes around the seat tube to protect both from any rubbing due to micro movements while riding.
  • Bar Tape
    • Trek supply this bike with black bar tape from the factory. The previous owner had replaced it with white bar tape which was quite grubby and worn when I got the bike. I wanted to swap the brake controls back to the UK convention (see about that in Maintenance/Adjustments) so needed to redo the tape anyway. I stuck with white as it adds a bit of interested to the somewhat muted gloss blue colourway (and the previous owner had fitted a white bottle cage to match). I went with a Bucklos Silicone+EVA tape (which does have a central adhesive strip). The old tape was a mess to remove – tape backing came away in places as I unwrapped it, stuck by the original adhesive to the bars, plus lots of it ripped – I had to do a lot of cleaning! This was my first time wrapping bars and I followed ParkTool’s excellent guide – it actually didn’t go too badly. The start/finish and levers were a bit fiddly, but thankfully the adhesive on the tape isn’t strong and seems to handle having to unwrap the last winding to reposition without issue so when checking as I went I could reposition.
  • Brake Pads
    • The original pads supplied with the bike are moulded (and have a reputation of having a poor feel even more new). I decided to fit a set of Shimano R55C4 cartridge brake shoes (with replaceable pads) – they’re used for their Dura-Ace, Ultegra and 105 groupsets and seem reasonably rated as an all-round set that’s not too pricey and are generally quiet. Their performance is noted as not being great in the wet but I’m not currently intending to ride in the rain often (just on wet roads) – if that changes then Kool Stop Dura 2 Salmon inserts will fit into the same shoes so I could get a set to swap in during inclement weather.
  • Bike Lock Mount
    • I bought a Litelok X1 as I needed a diamond-level lock for my Cannondale to meet the insurance requirements. I did buy a mount for it but there’s not enough room in the Cannondale’s triangle to fit it and have a water bottle (although it has a pannier rack I can strap the lock to instead). So I’ve fitted it to this instead – handy as I’m intending not to fit a pannier rack to this. If I’m cycling a circuit

Maintenance/Adjustments

Since it was a second-hand bike bought privately (from a student) it needed some maintenance and adjustment straight away.

  • Wheels
    • Front wheel – For some reason the front wheel had been clamped without having been settled straight in the drop-outs so it was slightly at an angle vertically (I noticed it wasn’t centered in the top of the forks. Someone had adjusted the brake centering to compensate for this! I undid the quick release, settled the wheel in the drop-outs under the weight of the bike and reclamped and then adjusted the brake centering and all was good.
    • Back wheel – when I checked the bike over I didn’t notice any lateral play in the hub and a quick spin of the wheel while lifting the rear seemed fine, but once I got it on the stand at home I realised the wheel felt like it had a little drag on it. The rear QR clamp was done up quite tight so I loosened it and that improved the drag. Removing it from the bike and the hub felt grindy – it reminded me of when I’ve been servicing my Marin wheels and get the preload a little too tight. It still didn’t feel entirely smooth and I had some spare 1/4 inch bearings around so I serviced the hub (cleaning, replacing the bearings and grease). On dismantling I’d found fairly new grease on the non-drive side (light in colour and very sticky) and black thinner grease on the drive side so my guess is a previous owner attempted to service the hub, just did the non-drive side and overdid the preload.
  • Steerer
    • Pre-load – Riding the bike home it felt like there was a little knocking from the steerer and getting it home I could feel a little. I undid the stem bolts, gave a quarter turn to the top cap, re-tightened the stem bolts. That solved it for a little while but then it started knocking again – however the spacers were relatively easy to turn so I figure it still wasn’t tight enough so I re-did it, this time tightening the top cap until the spacers were locked (checking there was no binding turning the handlebars). I did then have a repeat of an issue I had on my Cannondale Topstone where I start to get a click from the top cap on torque on the handlebars and bumps. I had checked the top-cap was still reasonably tight after I’d torque’d the handlebars but it must still have allowed for the tiniest bit of movement between the topcap and stem under load – I nipped it up a little tighter (with the stem bolts torqued it wouldn’t affect the pre-load) and that’s solved that clicking.
  • Drivetrain
    • Rear derailleur – On the ride home there were a couple of gears where it seemed to skip a cog on down shift and up shift and another with hesitation – I could see the cage was slightly off centre from the cogs so it just needed use of the barrel adjuster.
    • Front derailleur – The limit screws looked fine, but I didn’t check the cage carefully enough when buying as it shifted fine but while checking the indexing on the stand at home I spotted the front top of the cage has split with a slight gap and rust either side of the gap (not sure what could have caused this!). This doesn’t seem to affect shifting as the rest of the cage has enough strength so I may just clean and glue with a little epoxy steel at some point while keeping an eye out for a replacement on ebay.
    • Pedals – It was fitted with metallic light blue alloy flat pedals (likely from Aliexpress) which span freely and smoothly. After about 3 miles on the ride home I started getting clicking when pedalling even slowly/low effort and both sitting/standing (and 2-4 clicks per rotation). On the bike stand there was no clicking turning the pedals from either the pedals or bottom bracket and no play either. I checked the seat post clamp, tried flexing the frame statically (pulling/pushing sideways on seat post, standing hard on the pedals etc) and couldn’t reproduce. If I had the bike on a slope with my right foot on the ground and pushed on the left pedal to go forward then relaxed on the pedal to roll backward before stopping with force on the left pedal I got the click, didn’t do the same on the right. Given I was intending to swap pedals at some point anyway I put on a different set and, touch wood, that cured the issue!
  • Tyres
    • Rear tyre – There was an oval red sticker on the back tyre sidewall which turned out to be covering a 1mm puncture hole which the inner tube would bulge slightly through without the sticker. The tyres were both budget Triban tyres from Decathlon and 32mm wide – the max clearance officially is 28mm due to brake and fork crown clearance rather than width I think but these cleared fine. My intention was to swap over some better tyres I had around from my now scrapped hybrid, so I swapped both.
  • Brakes
    • Reversed controls – I bought the bike from a Canadian student who must have reversed the brake controls (as it’s a UK-spec bike – in the UK we use left for front right for rear, in many other countries it’s the other way around). I swapped them back to UK standard, replacing the inners at the same time. The rear inner had been dragging a little at the rear outer section but I found that was down to the inner (not sure if it was dirt or slight kinking or what), a new inner slid smoothly. I used a Shimano SIL-TEC coated cable for the rear as it has the longer run with more exposed, and a slightly cheaper Shimano stainless one for the front.
    • Pads – The brake pad positioning needed adjusting (on one side they’d worn to curve around the rim so taken off a thin strip of paint adjacent to the braking surface) and they were cheap moulded no-brand pads which felt rock-hard so I suspect were a bit old (potentially even original) – they certainly lacked a bit of bite.