poiuyt

Hi,

I have a 2020 Dual Sport 3 and would like to upgrade it (some items are worn out). The ideal setup would be the one seen in the 2021 Giant Roam 1 ("Deore" 2x10 (46/30 front, 11/42 rear): it's not too far of the current spec, but still a significant upgrade. But I can't find matching parts in the Shimano offering. The current one is an Acera 2x9 (46/30 in the front, 11/36 in the rear). The issue I have is that Giant is not specific about the actual components they are using (I found on the net that the rear derailleur is a RD-M5120, but that's it).

Reproducing it would then require some matching of different product ranges and I'm a bit lost:
- Crankset: To have a 46/30, I'm limited to gravel products, which are road products. I was thinking to the Shimano GRX FC-RX600-10, but what about the bottom bracket? The current one is a BB-MT500 (threaded — which seems to not exist anywhere). Should I change it too?
- Crankset, bis: the GRX FC-RX600-10 has a chainline that is about 2mm smaller than the current one (Shimano FC-MT210-2), and the distance between the 30 chainring and the frame is only a few millimetres. Is there a risk that the GRX might be to close to the frame/tires? Or is it possible to have some spacers? Shimano states in their specs that this crankset offers enough clearance for 42mm tires, I'm using 47mm.
- Front derailleur: given it's a 2x, from what I understood, it would be ok to keep the current one, but not optimum. Otherwise, I could also go for a GRX, but it's not clear for me if it would be compatible with MTB shifters.
- The capacity of the M5120 (long cage) is not sufficient (41T vs 47T): is it Shimano being to prudent in their specs or Giant having access to a special version of the M5120?

Otherwise, the alternative I've seen are:
- Replace the rear derailleur/cassettes by Microshift Advent (they have 11/42 9-speed, and a matching clutch derailleur): that would be the least disruptive, I have small reserves though: I don't know if it would be as smooth to operate as a deore and it's on the heavy side, but reviews are very positive about it. Going 10-speed 11/42 would also have some logistic benefits: the rear wheels would be interchangeable between my bike and my wife's.
- Going 11 speeds and take an XT RD-M8000, that has the correct specs, but it still not solves the crankset issues, and that would require me to replace the wheels (I know technically I could just replace the hubs, but at this product range, labour would be more expensive than a new wheel), because the free hub is not the 11 speed one. It would be "expensive for a Dual Sport", but given I haven't found a bike as versatile as the Dual Sport, I'm not opposed to spending more.

Any comment/thought?

Thanks!

hokiefyd 

The Microshift Advent 9 derailleur is a real workhorse. It is heavy, yes, but it does feel like it'd survive the zombie apocalypse. The derailleur and shifter will not have the same "light action" feel of the Shimano Deore. It's definitely a "heavier" shift feel. I will say the Microshift stuff feels more direct when you shift. By that, I mean it shifts to the next cog with intention. Whereas the Shimano stuff seems to "glide" or "slip" into the next gear, the Microshift stuff "clunks" or "slams" into the next gear. That's not to say it's unrefined...it's just a very positive shift...you know when it's shifted. After using both, I prefer the Microshift Advent products. I have an Advent 9 clutch derailleur on my fat bike, with their 11-46 9-speed cassette. It runs pretty nicely. I currently have a Deore shifter and Alivio rear derailleur on my mountain bike, but will upgrade that to the Microshift Advent 9 system at the next parts replacement opportunity.

travbikeman

If your bottom bracket MT500 is going bad, then would suggest replacing it with an MT800 Hollowtech II. My MT500 went bad, crunchy and such only 20 miles after riding my mountain bike. You will not find the MT500 in the U.S. If it works, keep it and use it as long as you have a Hollotwech crankset. Otherwise, spend a bit more for a better BB with better seals. I had replaced mine with the MT800, which requires a different tool, but is a better BB. Long story as to why I didn't make the LBS replace via warranty.

Not really certain why you would want to exchange wheels or hubs unless your looking at just upgrading the entire wheelset for lighter better parts? You have the following hub: Formula DC-22, alloy, 6-bolt, Shimano 8/9/10 freehub, 135x5mm QR This can handle the 10 speeds and 11 speed cassettes. As long as you don't purchase a Shimano micro spline cassette, you should be able to use all the way up to 12 speeds.

I switched my mountain bike over to the AdventX from the Altus 9 speed groupset it had. Microshift has some really nice products now. Reviews that I compared the AdventX to, consistently stated this was a better derailleur system than Deore. But not quiet as nice or smooth as the SLX. My son's bike has the older SLX 10 speed. It's fun to compare, but both systems are in my opinion are on par with shifting capabilities. The SLX is more quiet and lighter feeling to shift. Where as the AdventX has a bit more loud of sound with the click, but feels really good when it shifts. I've gone up hills on this bike and had no grinding of any sorts when shifting like I did with my Sub Cross's with it's Alivio setup.

Only issue and a minor issue at that I have with my AdventX is the paint. Dirt, gravel, mud seems to stick to it much easier than the Shimano parts.

poiuyt

Thanks for the feedback. I forgot another reserve of the Advent: supply seems to be an issue now (at least in Europe)

Thanks for the answer too.

Deriving from your remark, I can use any Hollowtech II crankset with any Hollowtech II BB? The GRX crankset I mentioned is also hollowtech II, so it would make the change easier, if I go in that direction.



From what I understood, there are 2 different lengths for HG free bodies: a short one and a long one, the short can fit up to 10 speeds cassettes, and the long 11+speeds cassettes. I also have a trainer (Kickr Core), that has the long version. To fit a 9 speed cassette on the trainer, I need to add a spacer (that is not required on the bike).

DorkDisk

One can fit an 11-34 (or larger) 11 sp cassette on a "9-10 sp" HG freehub. The same rule applies for 12 sp, in addition to the spline pattern requirement.

To see if a GRX crank will fit, first measure your BB width. If its 68mm, you're good. If 73, there is no way to make that fit. If a 68mm, your next issues are arm clearance and chainring clearance. Since you have the bike, eyeball your setup and see if you have 2mm to go towards the frame.

MTB and road hollowtech BBs are different (spacers, width, and longer threading) but can be used interchangeably. You may have to remove your setup and remove spacers to make it work though.

I'd suggest going to 800 GRX to save 100g over the 600 model.



68mm width for road cranks

Ryan_M

Weird coincidence, the GF has a 2020 DS3 and I have a 2020 Roam 1. I upgraded my drivetrain to a full M8000 setup and put my hand-me-downs on the GF's bike. It was pretty much a full M6000 package except the crank, which has now been replaced with a M6000 to complete the group.

Sorry I don't have any experience with the GRX line but if you have any questions otherwise lemme know.

poiuyt

Thanks for the explanation. I'm not at home this week, so I can't measure but will do it when I'm back. When doing my homework, I found a thread about someone willing to do it on a 2021 Dual Sport 4, but I can't transpose the experience: the 2021 DS4 has 68mm but 3 spacers, I don't have spacers (according to the picture I took for the serial number). But if it appears to be a 68mm, that's indeed a good thing, there is more offering in gravel products for this kind of cranksets.

Interesting, thanks to let it know. Which kind of chainring did you install? Did you use the MTB-ones (34/36 teeths)?

Ryan_M

Both bikes have the Shimano crank from their respective groups (M8000 and M6000), and both are 28/38t. My roam came with a FSA 32/44 crank that shifted horribly. The Shimano cranks are worlds better in that regard and the smaller chain rings suit our riding style much better too so win win.

Ryan_M

FWIW the GF's DS3 has a 73mm BB.

poiuyt

Thanks for the reply (and the confirmation for the BB bracket width). It looks like the solution is then either the Advent or spending big money and replace the wheel/freehub to have a XD free body. If I want to keep a similar upper gear, it would be necessary to have a smaller small sprocket. I see then two interesting combinations with the e*thirteen cassettes, assuming that specs are on the conservative side:
- the "fast" one, combining a 9/42 11 speed cassette with a 38/28 crankset (M5100 or M7000)
- the "climbing" one, combining a 9/46 12-speed cassette with a 36/26 crankset (M7100 series).

The question then would to know whether it's worth spending so much money on an "entry-level" bike instead of buying a new one. But I have the feeling I wouldn't find something as versatile as this kind of bike: gravel bikes are not as good off-road and cross-country MTBs are not as good on road/gravel trails.

Ryan_M

What's your typical cadence? My comfort zone is about 95RPM so I can get ~45kph from the 38/11 combo comfortably, ~55kph before I run out of legs but if I'm going down a hill big enough for that I'm happy to coast. I certainly appreciate the much lower gearing when I have to pedal back up that hill lol.

poiuyt

I don’t know my typical cadence, it's a metric I'm not following (I'm just mostly limited to average speed). I’m using the 46/11 and 46/12 combos a lot, and sometimes surprise myself trying to reach a fictional 46/10. I live close to the foot the Alps, in the North of the Po valley in Italy. My typical Sunday ride starts with 15km of flat with very low wind, so it’s the perfect conditions to ride at high speed.

DorkDisk

An option is to run a direct mount MTB crank with 46/30 rings. Something like a Cinch system will allow that (raceface cranks and easton chainrings).

Gearing is personal, but keep in mind that 46x11 is the same as yesterday's racing bike high gear (53x13). The DS has neither the position, weight, or aerodynamics of a race bike.

poiuyt

I finally did the upgrade that was the object of this topic, and give it as a reference if someone is interested. The issue was to keep a high gear equivalent to a 46/11. A 38/28 chainring and 9/42 cassette (e*thirteen) would have been the best solution on the paper, but 1. finding the parts was challenging: Shimano now only offers 36/26 in their current ranges (except XTR), parts from older ranges where very difficult to find, and 2. I contacted e*thirteen and they strongly advised against using a 2x with their cassettes. The other problem I had with this approach was that it could only work with e*thirteen cassettes, and I don't like to rely on a single provider (same issue with the Advent in fact, and I couldn't find a retailer that has the long cage versions...). To use this cassette I would also need to change the rear hub/wheel, and again I only found one supplier if I want to combine a XD free body and quick-release.

So I went with "Giant Roam 1" clone: I kept the current Acera 46/30 crankset and front derailleur, and bought a RD-M5120-SGS rear derailleur, a M4100 rear shifter (Deore 10 speed) and a M5100 front shifter (to have this single lever operation, it was otherwise not strictly necessary) and a 10 speed 11/42 rear cassette. It seems to work very well so far, but to avoid to wear the rear derailleur too much, I switch to the small chain ring from the third sprocket instead of avoiding the big/big combination. I had some fears about the 10-speed chain being stuck between the chainrings (bad experience with a previous trekking bike), but it works like very well.