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km 29er sizing question

1K views 12 replies 7 participants last post by  frankenbike 
#1 ·
Sorry if this sounds redundant - Offhand, simply wondering about Karate Monkey's 29 wheels & sizing up a suitable frame. Realizing being fitted in a shop for measurements will expedite matters, I'm leery about a couple of the local (nearby) store employees & classifieds owners being a bit too blase' in regards to what they wanna sell me - Thought I'd try here for some suggestions. Basically, height is 5'8, and was sold a 17" Specialized & 18" Giant in the past. Will the 29 wheels be better served by sizing down to a 16"KM, or "medium size"d 18"?? Thanks for being patient w/me!
 
#2 · (Edited)
captaind said:
Basically, height is 5'8, and was sold a 17" Specialized & 18" Giant in the past. Will the 29 wheels be better served by sizing down to a 16"KM, or "medium size"d 18"?? Thanks for being patient w/me!
What's your inseam? The KM frames are known for having a fairly high standover, so unfortunately your inseam may be important. There are those that say that standover doesn't matter, which is true to a point, but only to a point (you need some clearance from crotch to top tube). I'm 6' 1", have a 32" inseam and found the standover of the 18" KM to be too high for my liking.

Looking at the specs:

The 16" KM has a 22.7" ETT and a SO of 30.8"
The 18" KM has a 23.6" ETT and a SO of 31.9"

By comparison, a 17" specialized 26" wheel hardtail frame (stumpjumper) has a ETT of 23.03" and a SO of 30.8"

Based on standover and top tube length you'd be best suited by the 16" KM, assuming you're happy on the specialized you have (and it's a HT with similar geometry to the stumpjumper).

Don't worry about "sizing down" for 29 inch wheels or anything like that. The most important parameter (top tube length) is measured the same for both wheel sizes. The only significant difference with 29ers is that you have to pay a little more attention to standover if you're looking at a "conventional" (non sloped or V shaped) top tube, such as the KM's top tube.
 
#3 ·
Thank you VERY much, schmoe - you really went above & beyond, and I definitely appreciate it! My inseam's slightly over 29", so yeah, I think
your personal help makes 16" a better fit. It's funny (or weird), what got me
back into mt biking was a $50 (barely used) Diamondback that's so small I
eventually pawned it off on my girlfriend - thing is, the previous owner was
deceased, w/no size # on frame (If I had to guess, maybe a catch-all "small" designation). It was almost like a bmx bike on trails, nice when tight, and still ok
on drawn out tracks/fireroads. On the other hand, a friend once tried to push his
21" (can't remember model) Trek on me, and while I just coasted around his yard
a couple of times, I remember liking the rider positioning (he was shorter than me, go figure).
I'm excited to try a 29er, for many reasons. Not much cash at the moment, but these
boards are whetting the appetite! (again, THANKS!!!!)
CaptainD

Schmoe said:
What's your inseam? The KM frames are known for having a fairly high standover, so unfortunately your inseam may be important. There are those that say that standover doesn't matter, which is true to a point, but only to a point (you need some clearance from crotch to top tube). I'm 6' 1", have a 32" inseam and found the standover of the 18" KM to be too high for my liking.

Looking at the specs:

The 16" KM has a 22.7" ETT and a SO of 30.8"
The 18" KM has a 23.6" ETT and a SO of 31.9"

By comparison, a 17" specialized 26" wheel hardtail frame (stumpjumper) has a ETT of 23.03" and a SO of 30.8"

Based on standover and top tube length you'd be best suited by the 16" KM, assuming you're happy on the specialized you have (and it's a HT with similar geometry to the stumpjumper).

Don't worry about "sizing down" for 29 inch wheels or anything like that. The most important parameter (top tube length) is measured the same for both wheel sizes. The only significant difference with 29ers is that you have to pay a little more attention to standover if you're looking at a "conventional" (non sloped or V shaped) top tube, such as the KM's top tube.
 
#4 ·
captaind said:
Thank you VERY much, schmoe - you really went above & beyond, and I definitely appreciate it! My inseam's slightly over 29", so yeah, I think
your personal help makes 16" a better fit. It's funny (or weird), what got me
back into mt biking was a $50 (barely used) Diamondback that's so small I
eventually pawned it off on my girlfriend - thing is, the previous owner was
deceased, w/no size # on frame (If I had to guess, maybe a catch-all "small" designation). It was almost like a bmx bike on trails, nice when tight, and still ok
on drawn out tracks/fireroads. On the other hand, a friend once tried to push his
21" (can't remember model) Trek on me, and while I just coasted around his yard
a couple of times, I remember liking the rider positioning (he was shorter than me, go figure).
I'm excited to try a 29er, for many reasons. Not much cash at the moment, but these
boards are whetting the appetite! (again, THANKS!!!!)
CaptainD
All of us on this thread are built about the same. I too am 5'9" and have a 30" or so inseam. I have been on my 16" KM for a couple years now. Fit is nice. I also am like others on this board and keep raising my handlebar height. Mine is now almost like a BMX bike (not really)
:D
 
#6 ·
I'm real glad to get such unbiased feedback on 29er sizing, basically
my purpose in originally posting - of course, personal preference can
differ w/authoritative sources(namely the pierced 16yr old "shop mechanic",
or housewife looking to unload her ex's ride). Just wanna thank everyone again!

"yo no soy marinarer,
yo soy capitan."
 
#8 ·
16 or 18

I was in a similar situation and I got the 18 instead of the 16. I recieved it and found it was Actually about 19-1/2 center to top :confused: . It was 18 center to top of top tube. I got the 18 because the dimensions were closest to my other 29er except for the standover. I know I'm going to open a can of worms here, but what's "Stand Over". As long as the head tube length allows you to get the bars down far enough. I don't really care where the seat cluster is . . . too much. I have a 33 inch inseam. When I was looking for my first 29er I had one manufacture suggest 19.5 inch, and another 17.5. Both are very reputable. They just had different philosophies.

I'm going to keep the 18 because I noticed I have about 1 inch of toe-front tire clearance (Size 45 shoe). Some people have overlap and they don't care. I looked at the front center dimensions on the 16 and toe overlap could happpen.
 
#9 ·
Stand over matters to me

Hexonxonx said:
I was in a similar situation and I got the 18 instead of the 16. I recieved it and found it was Actually about 19-1/2 center to top :confused: . It was 18 center to top of top tube. I got the 18 because the dimensions were closest to my other 29er except for the standover. I know I'm going to open a can of worms here, but what's "Stand Over". As long as the head tube length allows you to get the bars down far enough. I don't really care where the seat cluster is . . . too much. I have a 33 inch inseam. When I was looking for my first 29er I had one manufacture suggest 19.5 inch, and another 17.5. Both are very reputable. They just had different philosophies.

I'm going to keep the 18 because I noticed I have about 1 inch of toe-front tire clearance (Size 45 shoe). Some people have overlap and they don't care. I looked at the front center dimensions on the 16 and toe overlap could happpen.
Standover is never an issue for anybody, until you have an unplanned 'getoff' and the twins are put in harms way. I'm around 6'0", with about a 32" inseam, and my medium (18) monkey is a little high in the TT for my liking. I figure that stems are cheap and plentiful, and they're available in a number of lengths, so opting for more frame clearance rather than less is always my route..

As for the toe-overlap, I'm fortunate (or unfortunate) enough to have girl sized feet for my height, around 42's, so that's not an issue for me. I feel for those who do have it though, it's nice not having to worry about which foot is forward depending on which way the switchback is coming at me...

Plum
 
#10 ·
In case anyone finds this useful, here is the geometry diagram of the Monkey. Note that the size is based on a C to T of top tube measurement. I think Surly should have this diagram on the Monkey page instead of as a downloadable PDF, it would help clear up this sizing surprise for some people when they get the frame and realize it's 1.5 inches bigger than they assumed.
 

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#11 ·
Standover also matters to me...

I also think standover is important, but that's just me. I rarely eat it, I ate it right onto the top tube of my last bike.

If you like to ride technical stuff the do factor it. But if want to build up a fireroad cruiser, then it's not such factor.

Monkeys have tall standovers, especially compared to the Fisher 29ers. A small Monkey has the same standover as a large Fisher, and the Fisher has the taller Reba compared to the Monkey's rigid.

My Monkey is in the mail and will be here this week. I deliberated over the 16 or 18 for about a week and decided to go with the 16 (which is really a 17.5) and just combo of a slightly longer stem and pushing the seat back just a tad.
 
#12 ·
The other stuff

frankenbike said:
In case anyone finds this useful, here is the geometry diagram of the Monkey. Note that the size is based on a C to T of top tube measurement. I think Surly should have this diagram on the Monkey page instead of as a downloadable PDF, it would help clear up this sizing surprise for some people when they get the frame and realize it's 1.5 inches bigger than they assumed.
Your right about that. Center to top of what? . . . Seat-tube, or Top-tube? But I do say a 18"s dimensions are close to what an 18" dimensions should be except for standover. Whether a 18" is right for you is on thing, but it seems a lot of 29er, 18" frames have top tubes around 23.5 - 23.8 and so on. Well you get the point.

I would like to try a 16 though with that shorter front center to see how it handles. As long as I don't have toe overlap.
 
#13 ·
One more thing to note...

Since the Karate Monkey has the bent seat tube, you will have less distance to drop your seatpost when needed. The smaller 16 has the least amount of seat tube left to drop the seat because the bend is so close. By that same logic, the larger sizes have plenty of room for seat post lowering.

Just one more thing to note incase it's important to you to be able to slam the seat down in technical sections.
 
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