DT Swiss Star Ratchet and EXP hubs

Equipment
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So i’ve been looking in to the star ratchet hub system a bit have a few questions. As far as I understood it DT Swiss had a patent on a double-floating ratchet disc design that was very popular and reliable. That patent ended and now many other companies are making similar. To stay ahead of the curve DT Swiss had to innovate and came up with EXP. With this design one of the ratchet discs is fixed and the other is driven by the same spring as the double disc design.

Lots of people are claiming EXP is a ‘regression’ and worse than the original double disc design, though obviously, DT Swiss thinks it’s better, or at least marketable. The obvious benefit I can see is that it is lighter, but it must be pretty marginal.

Can anyone explain what they see as the pros and cons of each design are?

I guess the ‘criteria’ are weight, maintainability, reliability, and internal/hub drag. Anything else to consider? If you have a choice of the older 240 or the 240 EXP which would you go for?

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EXP moves the drive side bearing out a bit, possible improving stiffness. IMHO, EXP’s are a little easier to assemble, just spin the last bearing in. I also think the exp may be more susceptible to failure from to much grease (I stripped a 36t - I can only assume I had to much grease around the ratchet). I didn’t see any problem w/ the old design. Absolute Black made a neat hub, same looking ratchets but no springs, magnets!

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That AB hub looks sweet.

So not really much in it between the previous design and the EXP?

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No. And I think only the 180 & 240 are exp. 350’s keep the old design.
Somewhere I saw an aftermarket spring, it was a flat wire (vs round). I may try it.

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I think from the end user perspective, it’s just different. DT swiss did this for product differentiation. They basically just fixed one side of the ratchet in place.

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If you have Star Ratchets on your other wheels, stay with that so you can easily exchange parts. If you don’t, it doesn’t’ really matter. If you’re a road /gravel/tri person, the some 18t star ratchets can be silent when you have the right ratchet rings and they are greased right.

The weight is about the same, the Star is more reliable than the early EXP, and the Star are more prevalent by far. The current hubs look a bit better, have the EXP, Ratchet LN, Pawl, the Hybrid Ratchet LN, the Hybrid Pawl. The hybrids hubs (e-bike) use a ~75-100gr heavier steel freehub and a larger ratchet ring surround. The LN hubs use the classic ratchet hub and a different seal than the classic star. The LN, classic Star Ratchet, and Hybrid all use the same clicker rings. The 36t and 54t rings don’t make much of a difference at higher wheel speeds, but nicer for slow climbing and low speed mtb stuff. The 18t is usually pretty quiet to completely silent.

The difference between the levels:
Hybrid: Steel freehub, bigger body, e-bike duty.
Tip: You can’t easily convert a 370 Hybrid Pawl to Ratchet, you need to get a special M35 Ringnut HXDXXX00N4021S from DT Swiss directly (~$15 part)

370: Cheapest hub, either Ratchet LN (classic star ratchet) steel or pawl freehub.
Pawls can be converted to Star with a kit - only try this on new hubs as old ones usually have the ring nut frozen it (I broke a good size vice trying to remove one).

350: Classic star ratchet. Get Aluminum freehub body on Shimano, Shimano Micro Spline

240: ~28gr lighter body than the 350 - achieved by machining of the hub body down further, EXP mechanism.

180: ~13gr lighter hub body than 240, ceramic bearings. Bearing smaller in some cases.

Anyway… just get the 350-level hub if you have a choice. You’re talking about a 80gr(total) weight difference for $350+. The 370s are fine, but the 350 option is usually about the same price. The 180/240 are about the worst values in cycling because the 350 exists. The 350 will last forever, work with everything, be quiet, and you’ll never need to think about it. The ceramic bearings aren’t worth it- they last forever and spin well, but so do the regular ones.

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I think the bearings in the 180 are smaller.

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I was looking at that, but it might depend on application. I didn’t see that on the model I was looking at. Looking at straightpull road disc - 28x15x5 vs 24x14x7, so the 180 is relying on the strength of the ceramics bearing race…and youre right.
( I just looked up an aero hub I have (ARC / ERC / Swissside style), it has the smaller ceramic bearing and I’ve got 3yrs on them, so no durability conerns in my eyes. )

FYI while I’m writing an explainer - There are also some misc hubs out there-
Dicut- thin, tall flange stylish hubs on OEM wheels.
Use “T-head” spokes, which are just straight pull spokes with the head hammered flat.
Tip: If you’re trying to reuse one of these for another wheelset, buy regular straightpull spokes, grab a hammer and hard metal surface, lay the spoke flat on the surface (by according to the blade direction), and pound the nail-head down (the ears will fold flat into a solid triangle; you can’t over-flatten it).

Dicut aero- ARC/ERC wheel models. Same as above, but with smooth flanges and narrower hub center on the front hub.
Note: I’ve found the to be a bit flexy with a lightweight TA with a larger rider.
There’s a 240 and 180 labeled hub, the difference is that the 180 has a bit of the centerlock interface milled away. The weight savings if negligible (~5gr) and the hub is the same otherwise; the ~75gr weight difference between the ARC 1100 / 1400 wheels is in the spokes.
Tip: If you build a wheel with these, you’re best served looking at a replacement spoke size from an OEM wheel and then adjusting to the rim you’re working with.

Wide spoke - on the G / GR / C / CR wheels, these use wider 3.2mm spokes (vs 2.2). Maybe on hybrid too.
Tip: If you’re buying a cheap DT Swiss wheel to use the hub/spokes on another rim, keep in mind the spokes won’t fit in a standard DT Swiss hub. I bought a donor wheelset for the spokes because it was cheap, then tried to mix/match the spokes and the plan blew up in my face.
Bontrager/Giant/Roval/FFWD/Syncros - custom hub shells with DT swiss freehub/axle/bearing layouts. Tip: If you build a wheel with these, you’re best served looking at a replacement spoke size from an OEM wheel and then adjusting to the rim you’re working with.

(if you’re wondering, I buy used hubs off of ebay/Pinkbike and pair these with new carbon rims and spokes for my own wheelsets. I’ve made some mistakes!)

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Yeah. I’ve got an old Rolf wheelset. All dt swiss 240 internals. It had the 18t, and unlike your experience, its obnoxiously loud.

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Oh no! Did you use the DT Swiss special grease? It’s special. https://planetcyclery.com/dt-swiss-special-grease-20g-tube?gclid=Cj0KCQiA3eGfBhCeARIsACpJNU81RimNPODhiFLRvbl90PfFZ9y2SwWl10f3rfGzY4zn0IXRttq-q-kaAqueEALw_wcB

When they’re loud, I usually add grease. Then if it’s still loud, I remove some of the grease. If it’s still loud, i flip the conical springs.

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HA! I got the special grease…
I tried everything. After ~15 min it sounds exactly the same.

Back to the EXP hub. I believe the first few batches of star ratchets had a problem w/ the teeth hardening. One more thing to watch out for. DT has a good warranty so should not be an issue.

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You just need to ride with a couple people that have loud hubs to see the difference :wink: .

When it was time to add some grease, I could definitely tell the difference after the add. That was with the 18 tooth. I’m using the 54s now, and they are louder than I like, but not as bad as some of my friends’ hubs.

Ultimately you just need to keep pedaling :joy:. I go on a beginner ride (mtb) on Sundays sometimes, for social and to spin a little after my long Saturday ride. I try to be conscious of that loud hub when I purposefully get behind slower people, and use it as a challenge to keep pedaling, maybe use a steeper gear that I normally would or single speed it.

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I road a set of onyx hubs for two seasons. Now everything is loud. :joy:

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My 180 had this problem and DT fixed it right away no questions asked.

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I have two sets of Light Bicycle wheels, one with a DT 350 54t star ratchet hub and another with DT 240 EXP 54t. I have done annual bearing replacements on both and find the original star ratchet to be simpler and the tools are easier to find in less expensive versions. The two wheelsets are the same model, just different hubs and the weight difference between the two are marginal - less than 50g if I recall. I’d recommend the DT 350 star ratchet to save money - 36t if you want to save some extra money (54t is totally overkill for road use, but great for gravel and MTB use).

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Agreed, and now there’s the 350SL with the same internals that gets the weight even closer. I do have one wheelset with 240EXP but that’s only because the deal was too good to pass up, with the wheels coming in $200 cheaper than my DT350 wheels from Nextie.