Geometry question
 

[Closed] Geometry question

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I'm looking at buying a new mountain bike online.
Working out what size to get I'm comparing geometry charts with measurements on my current bike.

I'm realising stack and reach are quite important in finding a good fit.

My question is, if a bike has 10cm higher stack than my current bike does that automatically mean handlebars will be 10cm higher than on my bike (if stem, spacers and handlebars arent a variable) ?

Currently my bars drop 4-5 cm below saddle height and I'd like my next bike to have the bars a little higher, around level with saddle.

Thanks

 
Posted : 09/12/2014 9:33 am
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It depends on whether the bike has bigger wheels and/or more travel?

10cm or 100mm is quite a big change if it is only coming from the frame and not travel or wheel size.

 
Posted : 09/12/2014 10:27 am
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Also depends on BB height. Two bikes can have the same head tube height but one can have a lower BB giving a longer stack measurement.

Are you comparing an old school XC bike with high BB and low headtube with a modern long travel bike with low BB and high head tube?

10cm difference sounds like a lot to be solely down to BB height so I would guess the head tube would be a bit higher too.

 
Posted : 09/12/2014 11:45 am
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To answer your question OP, yes all else being equal a 10cm higher stack will result in your bars being 10cm higher relative to the BB.

 
Posted : 09/12/2014 12:39 pm
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As rockplouh says. Remember that having a different length and rise of the stem and or bars will change the height of your hands too though! Stack and reach are measured vertically and horizontally respecively from the centre of the BB to the centre of the top of the headtube. So it has nothing to do with BB height.

 
Posted : 09/12/2014 12:45 pm
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Thanks
Yes it was just stack I was concerned with so I can get the right frame size, ballpark hand position, and then use different stem or bars to adjust in more detail.
Not worried about bb height
Appreciate all the replies. Thanks!

 
Posted : 09/12/2014 1:57 pm
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Not wanting to derail the thread but I don't understand this:


Stack and reach are measured vertically and horizontally respecively from the centre of the BB to the centre of the top of the headtube. So it has nothing to do with BB height.

If you have two identical frames but one has a lower a BB height then does that not increase the stack? If not, why not?

 
Posted : 09/12/2014 2:27 pm
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If you have two identical frames but one has a lower a BB height then does that not increase the stack? If not, why not?

I'm no expert, but I think it does increase it.

I think frood knows what he means, but has worded it badly.

[url= http://www.pinkbike.com/news/08ReachStackStandard.html ]Link[/url]

 
Posted : 09/12/2014 2:44 pm