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I am considering buying a Spider (or a Blur for that matter) and I'd like to get some feedback on sizing.

I am 5'10" with a 31.50" inseam (floor to crotch). There is no sizing chart on the Intense web site...

What's people experience out there?

BTW, I ride mostly trails (technical single tracks, fire roads), no drops, lots of climbing.

Thanks.

Denis
 

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At your height and inseam, you're on the cusp of riding a medium or a large. I'd say the determing factor will be your torso height.

I'd suggest going to your LBS and taking a Spyder out for a test to see if you feel cramped on a medium, or if a large feels to big. Buy what feels best....
 

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sizing the easy way

measure (preferably one w/ cm), a level, a pen, paper and a calculator. You'll need a friend to help measure you.

Reach measurement (A) = With your arm parallel to the ground, hold a pen in your hand and w/ a tape measure, measure from the center of the pen to the "dimple" at the top of your shoulder. Hint: Your muscle forms this dimple when you raise your arm. Record this measurement in cm.

Torso measurement (T) = Take a level and firmly place it in your crotch (to simulate pressure sitting on the saddle) hold it somewhat level or parallel to the ground. Feet are shoulder width apart, stand straight up and measure from the top of the level to your sternal notch (the pronounced dimple below your adam's apple). Record in cm.

Inseam (I) = Take shoes off and stand w/ feet shoulder width apart on a hard surface. Place level in crotch once again - keep it level w/ the floor - and w/ firm pressure and measure from the floor to the top of the level. Record in cm.

Do the following formulas:

A+T divided by 2 then add 6 = this measurement will equal your ideal TT length from saddle center to center of your handlebar.

I x .883 = this measument will equal the center of your BB to the top of your seat.

So for example using MY measurements:

My reach is: 63.5 cm
My torso is: 63.5 cm
My inseam is: 85.09 cm

63.5 + 63.5 / 2 = 63.5 cm + 6 = 69.5 TT measurement
85.09 x .883 = 75.13 cm seat top to ctr of BB*

If I take 69.5 and divide by 2.54 to convert to inches I get 27.36. I know that a medium Spyder has a 23" TT length, so 27.36 - 23" = 4.36" in stem length which is equivalent to a 110mm stem (4.36" x 2.54 = 11.07 cm). Stand-over on a med Spyder is 29.5" or 74.93 cm, so 85.09 -- 74.93 = 10.16 cm or 4" of clearance between the TT and the "jewels".

*This number/equation can be used to compare the saddle height to your current set-up for validation of the formulas.

Now that you have a working example, plug your own numbers in.

You can use these numbers to help: Spyder sizing:

Small - TT - 22" - SO 28"
Med - TT - 23" - SO 29.5"
LG - TT - 24" - SO 30.5"

You can also measure your current set-up and see how the numbers compare. Make note of what you like and dislike - ie too streched out, too cramped, etc.

Its also best to stay under 120mm on your stem so your handling doesnt get all funky (read: slower). I would size the bike according to your TT measurement and go from there. Keep in mind that you also can tweak these numbers. You may want a shorter stem to get you more upright, lower your seat for better DH control or run a seatpost w/ an offset to help legthen the TT a hare.

If this is all too confusing, ask questions or talk to JOSH or WADE @ Excel Sports - 800.627.6664 - They are fit guru plus they have Spyders on sale right now!

Good Luck - Good Dirt!

Matt[/QUOTE]
 

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Hey Mat, I think if just go with Top tube length and standover height is a pretty good way to measure. The best being , of course is to just sit on the bike. But really, your way may be good but not everyone has a Masters Degree in Science. It gave a headach just reading it.Sorry I`m not trying to get you mad, but there`s got to be an easier way to size up a bike. Happy trails Elmo
 
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