To the point: Is this combo even physically possible? Is it asinine? Weight? Friction?
I recently picked up a used Madone 5.9 frameset for a ridiculously good price.
I can't afford all the fancy DuraAce components, so I'm cobbling together what I can, but still want to keep the weight down.
I do not race, but I do go really, really fast. I also live in Portland, so there's a good deal of hills around here. I intend to do 60 miles to the coast with this build, which will go over the Cascades (baby mountains, more like big hills).
Now to build up the bike -
Looking for some wheels, found a set of Shimano Alfine 8sp wheels.
"Shimano Alfine disc wheelset perfect for commuting. The rims are disc only 28 hole Shimano medium v's. The front hub is an Alfine generator hub and the rear is an Alfine 8spd internal hub. The set is basically brand new, I only used them for a few weeks before deciding to go back to single speed riding. They come with center lock rotors as well as the rear shifter. Asking $250 or trades"
Reading the forums, people have concerns about the weight.. but do these full wheelsets (the pair coming in at 3,600g/8lbs) really weight more than a pair of decent aluminum wheels + gears ( http://weightweenies.starbike.com/listi ... roadwheels" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false; ) ??
I was attracted to this combo because of cleanness and possibly a loss in weight - no derailleurs, single front gear... is that moot?
And lastly, I've heard internal gears are less efficient. But compared to what? I'm not getting duraace stuff otherwise. More like 105 or maaaybe Ultegra.
A lot of questions, but really it's all only one.
Thank you for any thoughts and insight!!!
Aside from compatibility, I honestly wouldn't bother going internal on that kind of bike. It suits commuting where the massive gap in the gear ratios doesn't really matter, but on a road bike it will be very noticeable. You will also be 'missing' the easiest and hardest gears from a standard set up, so long steep climbs could be an issue as could screaming down the other side
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jesiah wrote:cool story, bro.
Not worth it in what sense?
You're asking about Alfine 8 - which is "mid range" - but really, we're talking about IGH in general, so let's begin...
The discs are not the issue. Alfine hubs are centerlock, so not running discs won't look odd at all.
The rear hubs are spaced for 135mm, although you can move around some washers to get them to 130mm, but it is not ideal, your chainline will be off. You will also need a chain tensioner, which is why horizontal dropouts are ideal - but on a Madone, there ain't no horizontal drop outs, so you'll be running a chain tensioner, which eliminates your "clean look," bro. Unless you run the "perfect chain length", but that's not going to be helpful when your chain stretches or when, inevitably, you need to remove the rear wheel.... speaking of which...
Also consider that changing a flat is a p.i.t.a - not nearly as easy or quick as a traditional hub with quick release. The hub is bolt on... heavy as sh*t.
Gearing: the hub (8spd) will end up weighing essentially the same as a full (average) 20spd set up, only you'll have dramatically less gearing options to your liking. On an alfine-11spd, for example, 2:1 ratio is the best you'll ever get. The gearing is less than ideal.
If anyone ever tells you that internal hubs are reliable, it's utter b*llshit. Go talk to any mechanic in a shop, chances are they'll tell you how much of a pain it is to work on, how often they go awry, and how often they breakdown. The ultra expensive Rohloff hubs? Better but not by enough to make their exorbitant costs worth it for most people who live with realistic budgets.
IGH hubs are inefficient compared to EVERYTHING. Heck, even microshift is more efficient. It isn't the gear mechs that is being referenced for "inefficiency" it is the actual interaction of chain to cog. You lose significant amounts of power with an IGH compared to a traditional set up. Period. They are not efficient in the very basic sense of what mechanical efficiency is on a bike. The differences between different group levels (example, Tiagra up through Dura-Ace) is not efficiency at all: they can each work perfectly fine and just as well as the others. The difference is quality, weight, looks, and employment of materials. When properly adjusted, they're just fine and mechanically efficient. The IGH method is not mechanically efficient.
There's your "cool story bro."
http://www.shimano.com/publish/content/ ... ype-..html" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;" onclick="window.open(this.href);return false;
The breadth of the gear ratio is worth considering. I only use 4 gears on my current 12 speed, though, really... but if I can't get the all-the-way lowest gear it might be sad.
Some of those things I care about, some are inconsequential to me.
The main issues it sounds like are the possibility of needing a chain tensor, inefficiency, and (news to me) the unreliability. Possibly the gear ratio.
I don't race, so spending 30 minutes fixing a flat versus 10 minutes isn't really a deal breaker. I never really get flats, anyway (one in 4 years, ride daily). Weight seems to be a 1-for-1 trade off, imho.
Thanks again... really appreciate the input.
http://thegoldenwrench.blogspot.com/201 ... d-hub.html
Then technically: the Alfine is designed to be installed with anti-rotation washers, which make sure the hub stays in the same position so the external gear-shift mechanism doesn't move. The Madone's carbon dropouts are not designed to take these. Plus it will be easy to overtighten the hub on dropouts designed for quick-releases, resulting in damage to the frame.
Long story short: I would heavily recommend against installing an Alfine hub on a high-end racing frame.
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