Benefits of frame size

[Rob]

I'm 6' tall. Some bikes I fit medium, others large.

What are the benefits of running a slightly small bike and running one a little bigger? I want it suited more towards downhill performance and jumping/drops.

I'm thinking a large frame with a short DH stem would be best.

The frame I'm getting is the Chumba XCL with Talas 36 RC2, Lyrik or Marz 55, with a DHX Air.
http://www.chumbaracing.com/xcl.shtml for specs.


Not in too much of a rush so I'm trying to do my research now.

[Code Blue]

Originally Posted by Rob

I'm 6' tall. Some bikes I fit medium, others large.

What are the benefits of running a slightly small bike and running one a little bigger? I want it suited more towards downhill performance and jumping/drops.

I'm thinking a large frame with a short DH stem would be best.

The frame I'm getting is the Chumba XCL with Talas 36 RC2, Lyrik or Marz 55, with a DHX Air.
http://www.chumbaracing.com/xcl.shtml for specs.


Not in too much of a rush so I'm trying to do my research now.

you described longer TT and shorter stem

[mtnbikerfred]

As long as the stand over height is OK, I'd go longer top-tube, short stem. I've got long arms, so the reach to the bars isn't too bad when I'm sitting on the tread...

The benefits of the smaller frame would be "quicker" handling due to the shorter wheelbase, and a little weight.

The benefits of the larger frame would be stability at speed, and a more "hooked up" feeling due to the longer wheelbase.

[nappyt]

Originally Posted by mtnbikerfred

As long as the stand over height is OK, I'd go longer top-tube, short stem. I've got long arms, so the reach to the bars isn't too bad when I'm sitting on the tread...

Same here if stand over height is equal on both then TT is a bigger deal. I want to make sure my knees have the right placement over the pedals. To short a TT for a talk guy can make you feel like your riding a kids BMX. Long stem or not.

[TURNERob]

The longer wheelbase of a larger frame will aid also for dh riding.

[tbowren]

I used to like short TT because it makes the bike lighter, stiffer and more maneuverable. It's easier to get behind the seat because the bars are closer to the seat (i.e. less reach).

However, as I learn that I'm not a very good downhiller and don't have the guts to go super fast or the reaction times to handle the situations I was getting into, I started going with longer TTs. This made the bike more stable and climbing (both seated and standing) was much more efficient.

I was recently told "running a 120mm stem is so 1996".

[2wheel_lee]

See my sig.

Generally speaking, I prefer smallish mtb frames. This allows me to handle the bike more easily. However, they don't climb as well. I don't give a cr@p about the climbs - I want to have fun.

[bobzrag]

I've got a large & i'm 6' 3", my bike is probably a bit small for me, but i love the ability to move it around on the descents. I ended up putting wider bars (27") and a longer stem on it. I'm still getting used to being stretched out more, but I'm able to climb (instead of popping the front wheel up all the time) but still have fun coming down.

PS unless you are shuttling all the time, you are going to end up climbing - and it's frustrating when the front is popping up all the time.

[Schecky]

Like Bob I'm 6'3" and ride a large, which I like a lot for the same reasons as him.
My bike has a long wheelbase and I use a long stem also. That, along with the ETA, makes for a pretty good climber.

[nappyt]

I have had issues with longer stems causing my steering to feel less responsive. I had noticed the same thing with longer travel forks.

Good luck on your selection. A smaller frame will give you more control and rigid frame if you choose to go that route.

[Dino Brown]

Originally Posted by Rob

.....I want it suited more towards downhill performance and jumping/drops.

I'm thinking a large frame with a short DH stem would be best.

Woobie- The most simple answer is to purchase a frame that 1) fits 2) suits YOUR needs.

Considering you are purchasing a 5" travel All Mountain (not a DH/JUMPING specific) XCL- I believe the LARGE frame is the best fit. It will be the most comfortable.... most stable... most pedal efficient way to go!

If you were asking about a DH specific ride- that is a different story! It is quite common for freeriders to go one size smaller than they would for their XC bike. Some ride small frames when "the book" says they should be riding large frames. I generally like my bikes a bit undersized. I am not sure *YOU* would like the cramped feel though!

Remember- the XCL is an "all mountain" machine... that you will ride "all over" the mountain!

My suggestion- test ride each size! After only a few minutes, I am confident you will KNOW which bike is the better fit!

[dirttorpeedo]

Originally Posted by Rob

I'm 6' tall. Some bikes I fit medium, others large.

What are the benefits of running a slightly small bike and running one a little bigger? I want it suited more towards downhill performance and jumping/drops.

I'm thinking a large frame with a short DH stem would be best.

The frame I'm getting is the Chumba XCL with Talas 36 RC2, Lyrik or Marz 55, with a DHX Air.
http://www.chumbaracing.com/xcl.shtml for specs.




Not in too much of a rush so I'm trying to do my research now.

go with a large, you'll have a hard time climbing with a short frame with a too short of stem or frame.try a lg. frame with at least a 90mm stem.good luk.

[Flat Broke]

Rob,

I'm 5'11" and would be torn between the large and medium if the standovers were the same. But based upon the seat tube dimension, I'm guessing that they're not. Based upon the 19" medium seat tube vs the 21" large seat tube, I'd go with the medium if I couldn't get my hands on a bike to test ride (which doesn't seem to be the case since there are some local guys that have picked these up recently).

Now for the bad news... I'm not so sure the XCL's geo is really intended for the work you described...

I want it suited more towards downhill performance and jumping/drops.

A 69* head angle is definitely on the steep side of life for a "downhill" orriented ride. I guess that with a 36RC2, it would probably slacken the HA out to 68*, so it may not be that bad, but I'd double check with Chumba on how big of a fork they'd warranty on the frame, and what different AC measurements do to the HA. I'd also be worried about the standover for using the bike as a dirt jumper. Honestly, if you're leaning more towards hucking than AM/XC, I'd talk to Neil and Gabe about those Transition Bottle Rockets on the wall at Adrenaline. They are noticably heavier than the XCL, but are dialed more towards what you're describing as far as a bias towards DJ/Downhill. The only downside is that you will definitely feel the extra girth out on the trails and with relatively short seat tubes, you might have to really push to get full leg extension with a 410mm seat post in a medium.

Chis