Disc hub wheel set

bobinski

Hi,
I have disc brakes on my commuter.The rear is built around DT Swiss TK540 Black 32h On a Shimano Alfine 11Spd hub. The front (same rim etc) has a shimano dynamo hub and runs my front light. The combination is pretty heavy. Its fine when i get it up to speed but starting from stationary is hard unless i drop to a really low gear and spin like crazy. Mtfu comments aside can i realistically reduce the rotating weight? The rims are pretty beefy and made for rim brakes and the spokes look agricultural. I think the wheels seem to have been made for heavy commuting or touring and not to reflect the use of disc brakes. Or prhaps i am wrong and they reflect the use of the dynamo and Alfine hub? Anyway, I am interested in whether i can relaistically and safely reduce both wheels weight. Anu thoughts? Ugo?

ugo.santalucia

Yes, you can... There is no reason to carry a heavy rim, unless you are severely overweight. Most riders will be just fine on an ambrosio excellight. Double butted spokes as opposed to plain gauge can further reduce weight. Realistically you can shed a pound of rotating weight, which does make a difference in acceleration.
Drop me a PM and I can give you some options that don't cost the earth

huuregeil

I would say it would make very little difference. I have tk540s on my commuter and these are great rims, totally tough and reliable and really not so heavy, plus the wider rim means your tyres run fatter and you can get away with lower pressure, a perfect choice for commuting. When e.g. I take them off to service the hubs, I replace them with my spare set built on Open Pros. Can I tell the difference? No, not really - the marginal gain from the wheel is extremely minimal compared to the whole bike setup. I'd save your cash and stick with what you've got.

ugo.santalucia

huuregeil wrote:

I would say it would make very little difference. I have tk540s on my commuter and these are great rims, totally tough and reliable and really not so heavy, plus the wider rim means your tyres run fatter and you can get away with lower pressure, a perfect choice for commuting. When e.g. I take them off to service the hubs, I replace them with my spare set built on Open Pros. Can I tell the difference? No, not really - the marginal gain from the wheel is extremely minimal compared to the whole bike setup. I'd save your cash and stick with what you've got.

Of course it depends on the setup and the average commuting speed and conditions, but if shedding a pound of rotating weight makes no difference, then nothing does and we might as well all ride Rigida Chrina 36 on Tiagra hubs, 'cause there's nothing faster out there...

huuregeil

if shedding a pound of rotating weight makes no difference, then nothing does

For commuting this is more or less correct! (And it's not a pound, the difference in rim weight is more like 80g each, which really is nothing).

ugo.santalucia

huuregeil wrote:

if shedding a pound of rotating weight makes no difference, then nothing does

For commuting this is more or less correct! (And it's not a pound, the difference in rim weight is more like 80g each, which really is nothing).

There is about 110 grams per rim, which makes 220... there is another 160 grams in going from 2 mm plain gauge spokes to DB or 210 in going DB at the rear and Revolution spokes at the front.
My maths say that's about 380-430 grams, which is just shy of a pound

Not everybody races like you do... some ride up to 75% of their time as commuters. Commuting saves me 5.20 a day in tube fares, for some people working in central London is way more... there is nothing immoral in spending money on a commuter to make it a bit better.
One could argue that a set of high profile carbon wheels to totter around Hillingdon circuit in cat.3-4 is more of a waste of money.
You can spend your money on an estate car that take you places or on a TVR Tuscan to race on the track... horses for courses

huuregeil

ugo, I clock 120 miles plus per week on my commuting bike, which runs tk540s. Trust me, going to a lighter rim in this situation makes eff all difference! Save your cash, no point spending 150 quid on an "upgrade" that isn't - I'm all for making your bike better, but this isn't the way to do it. For reference, an Alfine hub and Shimano dynamo hub is a significant weight, this is the reason the wheels feel heavy!

huuregeil

And to put a positive spin on this, the upgrade you can make that you will notice is to upgrade your tyres and work out a good tyre size/pressure combination. You'll notice the improvement in rolling resistance (assuming you're not on an optimal setup already) and this will leave you fresher at the lights.

ugo.santalucia

Of course you don't have to trust my word... ask a reputable builder, someone who is not running a boutique making a hefty profit shifting you the latest 200 grams set of hubs... ask Harry Rowlands or Paul Hewitt or Pete Matthews... they will tell you that hub weight is pretty much irrelevant, as relevant as a heavy bottle cage or half a pound of body fat.
Since I swapped my Alex rims and 2 mm spokes with Ambrosio excellence and double butted, the bike is transformed

huuregeil

I don't disagree that rim weight is more important than hub weight. What I'm saying is the rim weight is not that relevant in this context. In other words, the change in "reponsiveness" with respect to a change in rim weight, is extremely small when you consider the absolute responsiveness of the entire bike (e.g. including over 2kg of hub). The spokes are a little bit irrelevant also, moment of intertia goes with radius squared, the rim is the major factor in a wheel's moment of intertia, tyres too.

The bottom line: I don't notice a difference going from TK540s (shimano hubs, nothing exotic!) to Open Pros on my commuter (extremely similar to the excellight's you're proposing), so I stick to my TK540s and gain because of their indestructability and their increased tyre volume. The answer to every "what wheel" question is not 32spoke Excellight/OpenPro/DT1.1, what's best changes depending on the context.

ugo.santalucia

huuregeil wrote:

I don't disagree that rim weight is more important than hub weight. What I'm saying is the rim weight is not that relevant in this context. In other words, the change in "reponsiveness" with respect to a change in rim weight, is extremely small when you consider the absolute responsiveness of the entire bike (e.g. including over 2kg of hub). The spokes are a little bit irrelevant also, moment of intertia goes with radius squared, the rim is the major factor in a wheel's moment of intertia, tyres too.

The bottom line: I don't notice a difference going from TK540s (shimano hubs, nothing exotic!) to Open Pros on my commuter (extremely similar to the excellight's you're proposing), so I stick to my TK540s and gain because of their indestructability and their increased tyre volume. The answer to every "what wheel" question is not 32spoke Excellight/OpenPro/DT1.1, what's best changes depending on the context.

I find excellight/open pro more than adequate for commuting, even involving heavy bags... most people successfully ride Paris-Roubaix sportive event on OpenPRO... they are very versatile for the < 100 Kg rider. Tyre choice is limited to 23-28 and of course a wider tyre cannot be fitted, but I assume the OP doesn't want lighter wheels to then fit 32 mm marathon tyres...
Some commuting bikes are not clunky pieces of junk and do benefit from lighter wheels. An example the Genesis day one Alfine is a pretty nice commuter and deserves lighter wheels over the heavy ones it comes with... others are happy to enjoy the sunshine on a Pashley and that is also a nice way to go to work which requires no upgrades whatsoever.

bobinski

This has turned into an interesting discussion!

I hover around 80kilo's. I am reasonably fit for my 49 years and fwiw I am at the top or near the top for my age group on some of my strava segments,at least when riding my sl pro. I am a fair bit slower though on my commuting bike,a Kinesis cross pro 6 frame with the Alfine etc. I run gatorskin hardshells because its a faff to change a tube with the Alfine and so I want to avoid punctures. I could change the front i suppose to a standard gator... Anyway, like I said its a struggle getting the commuter up to speed. I always feel safer being able to pull away from lights etc at a reasonable pace and the taking primary. Of course the bike and wheels are much heavier than my planet x slpro and model B's or rs80,s but the difference is significant.And as I age i doubt it will get any easier! And I am not so heavy that i thought it would be a risk to go for lower weight wheels.

Thanks for all the input.

Bob