BHS SL190 rear hub -- too light?

[bobonker]

This may be blasphemy to ask such a question on this forum, but is the BHS SL190 too light?

At $90 and 190g, it is a very attractive option compared to the BHS SL210 (210g) and the Novatec F482B (245g) and even the Novatec F482B-SL (230g).

I haven't held one in my hand, but from the pics, it looks noticeable thinner in the hub area between the flanges. Will this make the hub flexy/flimsy?

Thanks,
Bob

[prendrefeu]

Blasphemy!
There is no such thing as too light, only well engineered and poorly engineered. That said, the BHS offerings have been known to be remarkably great hubs (especially considering their price). As for this new one: why not take the plunge and see how it holds up? It's only $90, and it's only a hub. It's not like you're taking a leap of faith on a fork possibly failing.

Even Extralite hubs have been known to fail, so keep in mind that product/material/engineering failure is not always in direct correlation to the price paid for said product.

[eric]

Will this make the hub flexy/flimsy?

No. Compare the large diameter 'tube' between the flanges to the tiny thin one between the flanges of a old Campy hub. Those held up just fine as long as you don't lace the rear radial on the drive side- the tiny little tube can't transmit the torque. I think the UL190 would be fine, even for radial lacing on the DS.
I've laced SL211s 1x on the DS and that works fine.

[pushstart]

I have this hub (it looks to be exactly the Bitex ED hub) on a Farsports 50mm wheel. I don't have a ton of miles on this yet (maybe 500-700), but I have not had any issues or noticed anything off about how it rides. In general I trust BHS stuff too.

[pushstart]

I have this hub (it looks to be exactly the Bitex ED hub) on a Farsports 50mm wheel. I don't have a ton of miles on this yet (maybe 500-700), but I have not had any issues or noticed anything off about how it rides. In general I trust BHS stuff too.

Oh, and for reference I weigh 175-180lbs.

Of course the SL210 hubs are great too. I have built a couple wheelsets with those and probably would get them again if weight was not the top priority.

[Devon]

I beg to differ with the "There is no such thing as too light" comment. If something is too light you could face decreased performance - you need a certain amount of weight to provide momentum and to keep the thing on the ground, you're not trying to take off are you. Wheels that are TOO light could be prone to skipping/skidding on rough/wet roads?

[prendrefeu]

Hi Alex, two things.
First, your argument has been discussed before here on Weight Weenies and elsewhere on the internets.
Second, do the math and get back to us: what percentage of the total system (rider+equipment) is a light bike? Do you really, genuinely think that a ridiculously light bike will compromise the total system weight enough to mitigate grip? Really? If your argument was in regards to fighting nasty sidewinds, then possibly yes but not absolutely.

Here's a related hint that took 10 seconds to search and find: viewtopic.php?f=3&t=76240&start=0
There are many, many more related topics that cover your argument in depth.

Also: this is WEIGHT WEENIES, not Bike Forums, not Road Bike Review, not some other generic forum. Stick around and you too (just like everyone else here without exclusion, myself included) can learn a lot! It's quite an amazing forum for knowledge.


A distant third: you aren't the only Alex here on Weight Weenies. I don't mean to insult you in this statement (if I did, I would have pulled a "Little Britain" reference), but that's just to point out that there are many brilliant people here, not just your self.

[Devon]

This is exactly why I emphasised so strongly the use of my word could. There are too many factors to speak theoretically about such things.

[xjbaylor]

This is exactly why I emphasised so strongly the use of my word could. There are too many factors to speak theoretically about such things.

Except that in the case of cycling a rider will always be present. I can think of no situation beyond the wildly theoretical in which a safe or effective system weight would depend on the bicycle itself as some form of ballast.

I can see the argument that a paper weight or hammer is "too light" at some point, but the conversation is clearly about bicycle components and all statements should be viewed in that light.

[Devon]

I was basing my point on multiple reports/reviews of ultra light wheelsets giving negative performance and resulting in effects as I listed such as poor grip and skipping on rough surfaces.

Very basic physics will also tell you that a rotating part which is 'too light' will also be unable to maintain a rotation for as long under certain operational conditions. Take for example lightweight flywheels in race cars - when fitted to a road car they give negative performance as the RPM drops too low between gear changes as the weight of the part is too low to maintain momentum. It makes sense for this theory to carry over to a wheel. Although obviously this would apply more to the rim/spokes, some effect from the hub would be present.

I also imagine that something again too lightweight could be more susceptible to uneven weightings provided by tubes/tyres/valves.

[prendrefeu]

I was basing my point on multiple reports/reviews of ultra light wheelsets giving negative performance and resulting in effects as I listed such as poor grip and skipping on rough surfaces.

Please provide references. Genuinely, please provide references. We'll wait.

No offense, but you are relatively new here, and there are wheelsets being used daily which are near 900g for the set without nary a word of "too light" or "losing grip."

Per your signature, it appears your current lightest ride is on target for "7kg", so I must ask you: have you ever ridden a setup that tilted the scales at less than 5kg? Did you find that you lost grip?

Very basic physics will also tell you that a rotating part which is 'too light' will also be unable to maintain a rotation for as long under certain operational conditions.

You still aren't doing the math, and physics theories are described in vacuums but in reality we do not live in one. On the track there is a preference for heavier wheels because they will retain greater momentum going forward compared to a light wheelset. The track surface is also mostly smooth, there is no climbing (no matter how steep the banked track is, that is not a climb) and it's pretty much just straight with two transitional left turns. On the road, heavier wheelsets might have an advantage depending on the terrain/route, but lighter wheelsets are not fledgling in their "loss of grip" and they too carry an advantage depending on the terrain route. But, Alex, your argument is that the wheelsets can be too light... despite the weight difference being a very small fraction of the total system weight.

Please, indulge us: what are these "certain operational conditions" where a light wheelset will lose grip?

[kulivontot]

700C wheelset will spin at approx 6rpm at 30mph. I don't think any comparison to automotive flywheels is even remotely relevent. Continue hand-waiving though.

[HammerTime2]

kulivontot, I believe you meant approximately 6 revolutions per sec, not per minute.

[Calnago]

Regarding the "light wheels lose grip easier" comment... hmmm... I don't follow that logic at all. While I agree that wheels can indeed be too light depending on the riders weight and use, etc., the only reason a light wheel will "lose grip" under my 195lbs of downward force is if I fly over a crest or somehow defy gravity or because of the tires themselves, but not because the wheel itself is "too light".

[kulivontot]

Sorry. 360 rpm still !=5000 rpm