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Old 08-16-12, 09:22 PM   #1
nadimk
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Help with wider Q factor!

I have a new single speed mountain bike with Time ATAC pedals and Deore XT crank, standard BB width. Shoes are SIDI Spiders. Here's the problem. The Q factor is much wider on this setup than my previous one and it is uncomfortable. The Times have some lateral float, but not enough.

Has anyone shortened spindles on these pedals?

Does anyone know of mountain bike shoes that have lateral cleat adjustment in the soles?

Thanks.
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Old 08-16-12, 10:15 PM   #2
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Has anyone shortened spindles on these pedals? <-- if you have where to built one for cheap, it looks like a good option

Have you tried changing the crankset BB axle for a shorter one?
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Old 08-16-12, 10:42 PM   #3
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Have you tried changing the crankset BB axle for a shorter one?
+1

It's an SS, so derailer chainline is a non-issue. Get those arms as close to the frame without touching if you haven't already done so. Then of course adjust the cog as necessary.

How much room do you even have with the shoes? If you move them too close, they'll rub the crank.
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Old 08-17-12, 09:35 PM   #4
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Since the term Q-factor started to show up in magazines, many got quite anal about it. Same with stiffness and other stuff that pretty much for week end riders is just non sense to be worry about.
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Old 08-17-12, 09:43 PM   #5
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Since the term Q-factor started to show up in magazines, many got quite anal about it. Same with stiffness and other stuff that pretty much for week end riders is just non sense to be worry about.
You should ride the spinning bikes we had at school and see if you still feel that way. A couple of us couldn't figure out why our knees were killing us until we figured out it was the massive q-factor on those terrible machines.
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Old 08-17-12, 09:49 PM   #6
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I believe you, and that's the reason I can't go to any gym to do spinning classes (dont need to learn how to spin too), the bikes just sucks , i see what you see You forgot to mention the super wide and short saddles too


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You should ride the spinning bikes we had at school and see if you still feel that way. A couple of us couldn't figure out why our knees were killing us until we figured out it was the massive q-factor on those terrible machines.
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Old 08-17-12, 11:25 PM   #7
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Have you tried changing the crankset BB axle for a shorter one?
Not sure how you would do this, as the OP is saying the bike is new, and all current XT cranks have a fixed width BB axle.

For the OP, are you really sure that you now have a wider setup by just using stock components?

You don't say what model XT crank you have, guessing M770 or M780 as it's new, these have a fixed width, as all external BB cranks do, if you have an older square taper you could have a narrower chainline / Q factor if using a narrower BB spindle.
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Old 08-18-12, 05:24 AM   #8
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The only pedal I know that has different axles to fix problems with the Q-factor is a pedal from new-Zealand called Keywin but no idea if their mtb pedals have the same feature. Probably they do. This guys have been in the market for around 30 years just in case.
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Old 08-18-12, 06:26 AM   #9
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You should ride the spinning bikes we had at school and see if you still feel that way. A couple of us couldn't figure out why our knees were killing us until we figured out it was the massive q-factor on those terrible machines.
Irrelevant. The OP is not talking about a spinning bike, and you're not going to find an actual production bicycle with the huge Q of an exercise bike.

You have to wonder, if minor Q differences are so important to bicycles, where was the outrage over outboard bearings? That system added 5-10mm Q to all bikes. And FWIW, most Q problems people had on bicycles was from Q being too narrow, not too wide.
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Old 08-18-12, 08:26 AM   #10
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Irrelevant. The OP is not talking about a spinning bike, and you're not going to find an actual production bicycle with the huge Q of an exercise bike.

You have to wonder, if minor Q differences are so important to bicycles, where was the outrage over outboard bearings? That system added 5-10mm Q to all bikes. And FWIW, most Q problems people had on bicycles was from Q being too narrow, not too wide.
Too narrow is a problem? I think Graeme Obree and his "Old Faithful" would have something to say about that... http://en.wikipedia.org/wiki/Graeme_Obree

I'd like to see some data on the outboard bearing claim. For fun I measured my mid 2000s Trek with an ext BB and it was no wider than any of my other bikes with square taper cranks. Sure, the bearings are further out but the arms are shaped rather straight to compensate.
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Old 08-18-12, 08:41 AM   #11
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I'd like to see some data on the outboard bearing claim. For fun I measured my mid 2000s Trek with an ext BB and it was no wider than any of my other bikes with square taper cranks. Sure, the bearings are further out but the arms are shaped rather straight to compensate.
eggzactly. chainstays and pedals determine Q factor more than bearing type. from what i've seen working in a shop, most square taper crank systems are wider at the axle than the outboard bearing type, but they still clear the chainstay by the same distance. obviously i'm comparing triple to triple and double to double.
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Old 08-18-12, 08:44 AM   #12
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Outrage here.

I've gone back to internal bearings on vintage bikes simply due to the Q factor using "modern" cranks. But the set-ups/bb width on modern bikes seem to compensate fine, I have no complaints with my newer Specialized bikes.

Our gym switched to Keiser spin bikes, with an enormous Q factor. I quit in protest, as did others. They invested many thousands in those bikes, and the mommies just loved them.
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