A must to know measurements about your frame

[tjspride]

Hi guys, just got a bike and i would like to know what are the necessary measurements that you should know about your bike frame. For example your seatpost, recently i bought a cheap seatclamp from a friend, but sad to say it does not fit for my frame. so far the only measurement i know about my bike is my 30.9mm seat post. are there components that are in standard sizing? What about the head, the fork tube length, the crank, the hub, the stem and handle bar-are their measurements compliments with one another? So guys please help, your comment will be beneficial among newbies that would like to purchase second hand or bnew parts for their bikes..

[hyperion]

Important specs to know about your bike for compatibility:

BB type: mountain or BMX type (can be found on some DJ/street mtb)
BB width: 68mm, 73mm, 83mm (DH/FR)
Headtube / Fork / Stem diameter: 1 1/8in or 1.5 in or 1 1/8 top & 1.5 in bottom
Headset type: external or internal/integrated
seat tube diameter: 27.2, 30, 30.9, 31 ...
seat collar diameter: 34.9 etc
Rear axle / Rear Hub: QR or 10mm or Maxle
Rear axle spacing: 135mm (standard) of 150mm (DH/FR)
Fork / Front Hub: QR or 15QR or 20mm
Stem / handlebar : standard or OS (oversized)
brake rotors / adapters: 160mm (standard) or 180mm or 203mm

[karamazov]

front derailleur 34.9mm band
handle bar length: 35", 36" and 37"
seat collar 34, 35...

[anthrax76]

by necessary, i'll take it that you mean a regular juan and pedro must know.

head tube - old standard is 1", the current standard is 1 1/8" or "oversized" to some LBS

seat tube length from center of bb - normally used to determine the bike's size. note that you may have the same seatpost diameter but depending on the frame, you might have different seat clamp sizes.

steerer tube - if the fork is brandnew, it's longer than 8", although trim it down when installed. diameter should not be 1" or else, you'll need an adapter for newer frames.

crank - normally comes in 170 mm, but why bother, unless you're super specific about the length.

bb - if you're not going DH, no need to worry about this one.

stem - lengths, clamping and rise differ depending on application. it should be compatible with your fork's steerer tube.

handlebar - same as stem. there's 25.4, 27.6 (rare) and 31.8 clamping diameters, different lengths and rise (could also be a flat bar). this will depend on how you want to position yourself in the bike.

in short.....tambay ka lang sa LBS, you'll learn a lot. and you can also have a bike fitting (search the boards) so you can get the proper sizes.

[oberon]

Mountain biking is rapidly becoming rocket science... due to the numerous options you have. To learn everything about it can take years, mabe a college degree's worth of info. The easiest way is to bring the item to your local bike shop, or take a pic of it. More or less, the LBS can figure out what you need, so you don't have to memorize all these numbers. =)

[tjspride]

thanks very much mga sirs,

highly appreciate all your inputs, basically sir that is the main reason why I asked because its such a hassle to bring your bike at LBS specially if you are just planning to canvas some parts. These notables will not just be helpful to me but also to all those newbies out there. Just FYI, my bike frame is giant xtc team 09, ill post some pics to soon. ride safely pmtb!

[stevejobs]

I borrowed my colleague's digital caliper caliper to measure the rear suspension of my bike that I'm building and it was fun being able to measure with precision.

I'm thinking of getting one for my self online - so no more guessing work for me.

Here's a link: