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[Closed] Stu McGroos lets put this Alfine weight issue to bed once and for all thread!

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[#2293188]

If you don’t care much for Alfine hub gears you’d better hit your back button and go and look at something more interesting.

Right then, I built this

[img] [/img]

an On-One [s]gas pipe[/s] Inbred 29er with 30 speed SLX a few months ago with a view to switching to Alfine 11 speed when it came out. Now having put 2 or 3 hundred miles on it and never once leaving the middle ring I decided that the 8 speed Alfine would actually fit the bill coupled with the fact that I just couldn’t be bothered to wait any longer for the delayed 11.

Now as there has been much talk and opinion, informed or otherwise, about the extra weight of an Alfine set-up over conventional gearing I wanted to get a direct weight and weight shift comparison between derailleurs and Alfine so decided to utilise as many existing parts on the bike as possible.

So, to start, the weight of the bike with the 30 speed SLX gears was

29.63 lbs

Then I removed;

XT rear hub, XT skewer, 32 x 290mm spokes and stainless nipples, 11-34 10 speed cassette, 10 speed chain, SLX rear mech, SLX front mech, standard SLX chainrings, left and right SLX 10 speed shifters and cables and 2 zip ties.

Added were;

Alfine 8 speed hub with 20T Alfine Sprocket and fitting kit, 32 x 285mm spokes and stainless nipples, Alfine 8 speed trigger shifter and cable, BETD Goldtec 32T chainring, 4 x 5mm spacers (to get chain line and utilise standard chainring bolts) and SRAM PC7X Chain.

Weight of bike with Alfine was

29.68 lbs

However, that was all done at my mates (weighed with the gear cable wrapped round the handle bars), next day at home I came to set the gears up and found the gear cable was way too long, shortened it by 480mm and weighed in (at the post office) what I removed at 19 grams which converts to 0.04 lbs and brings the total bike weight down to

29.64 lbs

So to summarise, my bike with 8 speed Alfine is 0.01 lbs (0.008 lbs or 0.13 oz or 3.68 grams to be exact) heavier than the when it was equipped with 30 speed SLX which I think you’ll agree is diddly squat.

Surprised? Yeah me too. On reflection, you pick up an Alfine hub for the first time and you’re shocked at the weight and immediately start wondering if you’re doing the right thing but that’s because almost all of the complete system is there in your hands. As you’re removing your conventional components they weigh very little but put them in one box to carry to your van and viola, there’s all your weight!

And yes, you could argue that compared to XTR the Alfine is heavy and rightly so but you’re in a different market altogether, Alfine was designed for a shopping bike not to win World Cup MTB races and [u]costs[/u] accordingly.

Anyway, now the weight shift. Suspended the SLX equipped bike from the garage ceiling like this

[img] [/img]

with a single tie to the top tube adjusted to find the point at which the bike was balanced horizontally, this was measured along the top tube at 190mm from the front of the seat tube.

Did the same with the Alfine equipped bike

[img] [/img]

this time the balance point is 157mm from the front of the seat tube.

Not terribly scientific but showed a rearward shift in the balance point of 33mm. Again, because of all the previous talk this was a bit of a surprise too but in actual fact if you put an innertube and a few tools in a wedge pack under your seat you’ll get the same result!

Actually, while I’m here I might as well talk about gear ratios. Fitted 32T chainring and 20T rear sprocket, this gives me the same range as a middle ring x 1-9 + granny ring x 2 on my previous SLX set-up. Though I’ve never used granny on the SLX I’ve erred on the side of caution just in case. If I find I’m not using the lowest ratio I’ll switch to 32:18 which will give me the full middle ring range equivalent albeit with 2 less ratios (i.e. larger gaps) which will suit me fine.

So there you go, I’m gonna go and ride the thing now and let you lot digest and discuss.

Oh, and here is the finished article.

[img] [/img]


 
Posted : 17/12/2010 5:40 pm
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I'm not reading all that! 😀


 
Posted : 17/12/2010 5:44 pm
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Nearly 30lbs? Repost when it has the expected seven inches of travel at both ends.


 
Posted : 17/12/2010 5:44 pm
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Fantastic piece of geekery
*applauds*


 
Posted : 17/12/2010 5:44 pm
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Aaah, bless you Stu McGroo. I'd love to have that much free time 😉


 
Posted : 17/12/2010 5:47 pm
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30lbs built from gaspipe though, that would come down with a lighter tubeset.


 
Posted : 17/12/2010 5:47 pm
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You've cheated in saving weight by using 185mm spokes, they should be 260-something?


 
Posted : 17/12/2010 5:49 pm
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A couple of queries,

You say you installed hub and stuff.........?

AND WHY NOT JUST SINGLE SPEED IT...... YOU KNOW WE WILL GET YOU IN THE END.


 
Posted : 17/12/2010 5:52 pm
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wow thats actually making me rethink getting an alfine, probably the best it has ever been explained. is that similar with a rohlof as well or is that heavier?


 
Posted : 17/12/2010 5:52 pm
 br
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Good post Stu, nice to see 'actual' weight as opposed to the 'feels like 26lbs' approach.


 
Posted : 17/12/2010 5:53 pm
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Nice post though.


 
Posted : 17/12/2010 5:57 pm
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Good to see some real-life figures instead of the usual pro-derailleur waffle and prejudiced opinion. Well done!

All we need now is a lightweight Alfine designed for mtb.


 
Posted : 17/12/2010 6:07 pm
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Nicely done Stu,

FWIW, the posh gas pipe version with Alfine is 25.5lbs in this build

[img] [/img]


 
Posted : 17/12/2010 6:08 pm
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All we need now is a belt driven close-ratio alfine for the road!


 
Posted : 17/12/2010 6:08 pm
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Very good post, im currently alfining a bike myself and as im going from a 1x8 normal setup I will be gaining a bit more weight but do I care? Not one bit 🙂

Thanks for the effort put in to that..


 
Posted : 17/12/2010 6:11 pm
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Mods! Ban this filth! Actual empirical data backed up with photos? On an internet forum? Disgusting.

(PS. Well done, that was very interesting)


 
Posted : 17/12/2010 6:16 pm
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[img] [/img]
/p>

Nice bike! 8)

And good post Stu, awesome geekery at it's finest - a really good thread to be able to point folk to when they ask about the whole alfine thing!

Another myth/rumour to attempt to dispel is the one about all the mass being concentrated at the end of the bike affects handling etc...


 
Posted : 17/12/2010 6:19 pm
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Another myth/rumour to attempt to dispel is the one about all the mass being concentrated at the end of the bike affects handling etc...

Except IMHO it does. I have an alfine equipped cannondale badboy that I commute on every day and the concentration of weight at the rear hub is definitely noticeable when bunny hopping up kerbs or over speed bumps.

Don't get me wrong it's still a fab choice for commuting though, especially in this sort of weather.


 
Posted : 17/12/2010 6:27 pm
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This write up is useless, ruined completely by the inclusion of facts and evidence.


 
Posted : 17/12/2010 6:33 pm
 Del
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great post Stu. you have some work to do, to compare to the weight of my mighty P7 however - 33lb(!)
she rides wonderfully. 🙂


 
Posted : 17/12/2010 6:34 pm
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Great write up, liking the colour scheme as well!

Not tried the center of gravity test, you can feel it but soon get used to it.

I've weighed these three when converting from SLX & XT 27 speed to Rohloff & found they were between 270g & 390g heavier with the hubgear.

[img] [/img]
[img] [/img]
[img] [/img]


 
Posted : 17/12/2010 6:40 pm
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Nice post...lovin my alfine 8 spd on the fatbike after 2 years beach riding its fault free...and theres another going onto the 29er in the New Year...nothing worse than mechs jammed with grass and mud.
I reckon if you fit an Alfine and get even 2 years before a problem your still no worse cash wise if you cost a hub compared to mechs,cassette,chainrings etc...
and you will have miles more chain life from an inline chainline 😮
pity you also hadnt done 25,000 miles fault free riding on a Gates belt drive too then that would of been job done well and proper 😉


 
Posted : 17/12/2010 6:43 pm
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It wasn't the mass distribution so much as the drag that made me give up on hub gears. It was demoralising.

In the process (I did swap a lot of bits and it was a Rolfharris so more than an alpine) I saved about 3lbs (original bike weight was 32lb, down to just over 29lb now).


 
Posted : 17/12/2010 6:45 pm
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you’d better hit your back button

I hit my belly button, is that OK?


 
Posted : 17/12/2010 6:46 pm
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Nice post Stu, you should be writing this sort of stuff for publication, not free on a forum. Excellent work.

And I guess with a suspension fork the rear weight shift would be lessened.

Cheers,

APF


 
Posted : 17/12/2010 6:46 pm
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Is it wrong I actually enjoyed reading all that


 
Posted : 17/12/2010 6:47 pm
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drag? as in when freewheeling?
my bike had more drag with the previous Hope pro 2 than the Alfine 8 speed...
granted the Alfine 8 speed aint perfect with the gap between ratios but for me anyway reliability and low maintenance combined with a clean driveline and no clogged mechs has been great 😮


 
Posted : 17/12/2010 6:49 pm
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Not freewheel drag but because the Rolf has 2 sets of planetary gears the lower set (gears 1-7) have noticeably more resistance to pedalling than the harder set.

I decided that on my type of bike it wasn't worth it- I don't have sufficient problems with drivetrains- but on a lighter weight bike and in the right situation I can see why they're better.


 
Posted : 17/12/2010 6:52 pm
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I'm unconvinced by those weights! You'll also need to carry a 15mm spanner, so that's another 200 grams or so...


 
Posted : 17/12/2010 6:55 pm
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Excellent post Stu, most informative!

Kev


 
Posted : 17/12/2010 6:59 pm
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Why 200 grams for a 15mm spanner?, just carry one of those machined pressed alloy multi fit spanners...think there old things but they fit and work 😮
An Alfine takes about 5 seconds longer to remove with the cable than a bolt up single speed hub too...just something alot of folk complain about that really isnt a issue 😉


 
Posted : 17/12/2010 7:05 pm
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Although not really interested initially, I enjoyed reading that. I may have missed something but You're comparing weights with triple rings up front to a single ring up front, irregardless of ratios this would still contribute a considerable weight difference no?


 
Posted : 17/12/2010 7:10 pm
 Keef
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I can confirm the weights.
I was there,init.


 
Posted : 17/12/2010 7:12 pm
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Very good and appeals to my geeky side.
Thinking about an alfine just cannot bring myself to put one on my EBB Indy fab 29er as it is just too pretty.
J.


 
Posted : 17/12/2010 7:15 pm
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xcKeith

Yep but i know your scales start at -10 😆


 
Posted : 17/12/2010 7:16 pm
 Keef
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Oh, and btw,one or two of you may not of noticed,it is a 29er.(hence weight)
and the rear wheel wheel spoke length is 288,although 286 would of been ok....


 
Posted : 17/12/2010 7:16 pm
 Keef
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no Sticky,that was the temp in the shed.......


 
Posted : 17/12/2010 7:17 pm
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Just to add to the Alfine debate, I've been riding mine since Sept and can confirm the following additional scientific facts

[b]Useage[/b]
KM's covered 1065.40
Hours Ridden 62 hrs 50 min 50 secs
Used 29 times

[b]Maintenance schedule[/b]
Cleaned - Once (well hosed down the mud)
1 bottle green chain oil
1 X 9 speed jockey wheel (to replace damaged one, used a standard Shimano one, and seems to work fine)

Don't really care what it rides like, weight distribution, spacing between gears blah, blah, blah - it's the CASH savings I've been going for

So......still going strong


 
Posted : 17/12/2010 7:38 pm
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i thought you'd given up riding stu, how much for the 10 speed stuff?


 
Posted : 17/12/2010 7:45 pm
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All we need now is a belt driven close-ratio alfine for the road!

ir_bandito to the thread, someone has been listening in on us... 👿

however al - having used my alfine commuter for 7 months now.... you're dead right. also need an appropriate frame.

hmmm. get this off to Kingdom bikes, Paul and I'll take the credit thanks


 
Posted : 17/12/2010 7:45 pm
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Smashing post! More of this sort of thing I say.


 
Posted : 17/12/2010 7:48 pm
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Lovin the post McGroo...... but really, gears? HTF did you pursuade xckeith to get involved....?


 
Posted : 17/12/2010 7:51 pm
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Wouldn't it look better in purple?


 
Posted : 17/12/2010 9:21 pm
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First of all, I'll repeat what many people have already said to the OP, what a great post!

My solution to the weight distribution 'issue' was simply to move from a saddle bag to one of [url= http://www.chainreactioncycles.com/Models.aspx?ModelID=34149 ]these[/url]. In my case thats around 1.5 pounds of weight brought forward.

[img] [/img]

I'd be a bit worried using 5mm chainring spacers to get the correct chainline. To get around a 42mm chainline you can use [url= http://www.sjscycles.co.uk/sjsc-64-mm-pcd-4-arm-alloy-inner-chainring-30t-black-with-silver-teeth-prod3941/ ]this[/url] and its a solid piece too - 4mm thick. If you flip the sprocket around to get a 47mm chainline, I've been eying up [url= http://www.widgit.com.au/ ]this[/url] with amusement, and in future the granny on any of the new double chainsets should be great too.

My mmmBop with u-turn revs comes in at at about 29lb, or 26lb with singlespeed wheelset (however this also has much lighter 2.1" wtb nano tyres). For vertical dropouts, the only tensioners I found that work ok with a 42mm chainline are the YESS ETR-D and the Shimano one. With 47mm chainline, the One-one Doofer is ok (but I massively prefer the ETR-D anyway).

[img] [/img]


 
Posted : 17/12/2010 9:29 pm
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Have to admit I'm kind of at a loss as to how it weighs so much? You sure your scales aren't on the piss? Unless it's got a load of weight stashed in the finishing kit or tyres or something...

Oh, and sorry but
"Fitted 32T chainring and 20T rear sprocket, this gives me the same range as a middle ring x 1-9 + granny ring x 2 on my previous SLX set-up."
I have no idea what this means :mrgreen: Probably just me being dense but could you clarify it a bit?


 
Posted : 17/12/2010 9:32 pm
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