I have an old Trek 820 frame (from 1999-2000, I believe this is the one), which has some sentimental value to my wife. I'd like to use it to put together a working bicycle.

I can wrap my head around Shimano's road groupsets, but the trekking/MTB ones seem to be way more complicated :/ My question is: what are my options (if any) in terms of shifters, crankset and derailleurs if I wanted to use a 2x8 or 2x9 setup on this bike?

Are there any reasonable options for a 1x setup?

  • You'll need to know the front and rear wheel dropout widths, which will determine what size wheel hub widths you'll be using; your rear wheel hub width and hub type will determine what type of rear cassettes you can use, which will in turn limit your gearing choices. Imho you should consider "new old stock" from 2x9 of deore or higher levels rather than lower level more recent stuff.
    – Armand
    Commented Apr 28, 2023 at 15:51
  • I'd also consider buying a little-used bike from the 2000s era in good shape and just transferring the components over to your frame. At least pre-pandemic, there were a lot of "closet queens" only ridden a few times and then stashed in the closet for twenty years.
    – Armand
    Commented Apr 28, 2023 at 15:54
  • 1
    PPS - old front suspension forks from something like an 820 were low end to start with; a better-functioning 26" replacement fork will probably be a big part of the total parts cost for your project.
    – Armand
    Commented Apr 28, 2023 at 15:58
  • 3
    @Armand if this is a 2000 MTB, we are extremely likely to be talking 100mm front, 135mm rear.
    – Weiwen Ng
    Commented Apr 28, 2023 at 17:06
  • Good luck. Sounds like an exciting project! Make sure to add an answer here once you have finished. To add the ultimate proof of what worked for you and this frame. Commented Apr 29, 2023 at 13:43

3 Answers 3


The main consideration is you need to avoid boost cranks, which only work with boost rear ends. Most or all of the cranks still come in a chainline version compatible with 135 QR (same as 142x12 thru-axle).

For the rear wheel, any 135 QR 26" wheel will be fine as long as you're not trying to run a Microspline cassette. If you did want Microspline (which would be true if you wanted any of the "good" MTB 1x groups), there are 135mm hubs with it, but getting one on into a 26" rim likely would mean a custom wheel build.

CUES/Linkglide parts are just materializing in the aftermarket recently, so you'll encounter them while researching or shopping, especially if you're looking at 2x groups. If you wanted to go with one of them, that's fine and you'll do it using an HG freehub body, but the rule with them is that the shifter, cassette, and derailleurs all must be CUES/Linkglide. For this purpose you would probably want to keep it simple by getting an accompanying crank as well, since otherwise it would be easy to get into a situation where the gear range or match with the RD capacity numbers was awkward.

Generally speaking, frames from the era you have were much less imposing on crank/chainring clearance considerations than they are now that bigger tires and shorter chainstays are in vogue, so putting a current crank on them is unlikely to run into those kinds of issues. But, it's always a thing to look out for and check early.


Most modern systems are "designed" for 28/29 inch wheels (that allow lower ratios), so going with a modern MTB groupset will introduce a risk of "running out of speeds". But in entry level ranges, there are limited numbers of alternatives.

With such bike, I would start from the 46/30 Acera Crankset (FC-MT210-2, with the matching FD-T3000 derailleur - hard to find — and a Deore M4100 shifter - much nicer to have a single lever shifter with a 2x).

For the rear, there are two options: if a 11-36 cassette suits your needs, it's possible to stay with Shimano (Alivio, M3100 series). If you need a higher range (with lower gears), there's the option of the Microshift Advent (11-42 cassette, long cage version required). Between the two options, the Microshift is the more "modern" one, and more expensive.

Otherwise, as Nathan mentioned, the new Shimano CUES seems very interesting, but is a few ranges higher in term of price and quality and is not widely available.

In 1x, larger cranks (40T) would be required to compensate for the smaller wheels. These are typically found now with road components, and frame clearance might be an issue.

  • Thanks, this put me on the right track. I'm going to pass on Cues for the time being, I couldn't find anything available around here apart from cassettes. Acera M3000 looks like exactly what I need. I'm just a bit concerned about the front derailleurs listed here: bike.shimano.com/en-US/product/component/acera-m3000.html. All the 2x9 ones are "side-pull", and I'm not sure whether I can route the cable correctly on this frame (the original FD was bottom-pull). If side pull is a no-no on this frame, I think maybe microSHIFT MARVO FD-M462 might work.
    – Radek
    Commented Apr 29, 2023 at 19:42
  • @Radek the issue with most front derailleurs is to find one with a 46/30 cage (there are also M3000 with 36/22). The microshift 462 is 34/44, so won't work. I looked at the specs of my bike (that has this crankset) and got wrong with the FD, it's a T3000 (post edited).
    – Rеnаud
    Commented Apr 29, 2023 at 19:51
  • Given the type of riding my wife does, I was actually thinking of getting the 36/22 crankset. In which case FD-M2020 seems like a reasonable front derailleur option.
    – Radek
    Commented Apr 30, 2023 at 19:41
  • @Tarek, if your wife is fine with 36T chainring, a better recommendation would be to go a 1x (Deore 5100/5120 (depending on the larger large sprocket of the cassette) or Advent X). I don't really see advantage of a 2x over a 1x if you don't need the increased range. It might a bit more expensive, but it's much easier to maintain/operate.
    – Rеnаud
    Commented May 1, 2023 at 8:56
  • 1x would be my preference, but... should I be concerned at all about the chainline? The M5100 1x crankset has a 52mm chainline specced out. But Shimano's website says it's good for 135mm O.L.D. So I guess not a concern?
    – Radek
    Commented May 1, 2023 at 19:58

It took a while, but here it is. I ended up with a 10-speed 1x setup based on RD-M5120-SGS, FC-M5100-1, Deore SL-M4100-R, and a 11-46T CS-M4100 casette.

I'm not particularly happy with the wheels, but it's not easy to find something reasonable off-the-shelf for 26" these days.

It's not the lightest bike out there, but rides nicely and I'm pretty sure it will be a reliable, bomb-proof commuter / poor man's gravel bike.

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  • Thank you for the follow-up - don't forget to mark one of the answer as the "accepted" one with the green check/tick button.
    – Criggie
    Commented Sep 4, 2023 at 19:23

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