Crank to short???

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Crank to short???
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Posted: Nov 28, 2017 at 17:14 Quote
I guess I should start off by saying I don't ride a lot of dj or street. I have a spank tweet frame with 165 mm cranks. Dope ass bike, but I always feel as if my body is too high above frame. I've already messed with stack height, various bar heights, but I still feel like I'm missing somthing. Could the short cranks effect how the bike feels below me. Maybe I just totally suck at riding dj......anyhow any thoughts on the matter is appreciated -

Posted: Nov 29, 2017 at 7:55 Quote
it sounds like the bike has too high of a bb for your taste?

Posted: Nov 29, 2017 at 8:51 Quote
Your probably spot on. I should probably measure it and compare it to other djs. Couldn't find bb height listed anywhere online. Was thinking larger crank arms might help the feel?? 170?

Posted: Nov 29, 2017 at 9:15 Quote
since you should have your cranks level while riding, longer cranks wont really change anything in terms of "ride height"

Posted: Nov 29, 2017 at 12:45 Quote
adrennan wrote:
since you should have your cranks level while riding, longer cranks wont really change anything in terms of "ride height"

Yeah, I agree. Crank arm length has nothing to do with feeling like you're standing high over your bike. There's actually a trend in BMX and DJ in favor of shorter cranks (closer stance, plus more room for barspins on 26").

If you feel like you're leaning/hunching down too much, you may benefit from taller bars. Like, a lot taller.

What stem, bars, and fork do you have?

I personally like a taller setup, (6'1", long legs). 4" rise bars with an 80mm travel fork (sort equivalent to 3" rise bars and a 100 mm fork).



STOUT Bikes currently has some 4.5" rise bars https://www.pinkbike.com/u/mattty/

Otherwise, Atomlab 3" PimpLite risers combined with top load or riser stem....

Posted: Dec 1, 2017 at 6:39 Quote
Strange, the Tweet is considered a DJ and with a 69 HT angle, it should really have a negative BB (below axle line) but I couldn't find BB height spec quickly. .

Posted: Dec 1, 2017 at 7:05 Quote
cmc4130 wrote:
adrennan wrote:
since you should have your cranks level while riding, longer cranks wont really change anything in terms of "ride height"

Yeah, I agree. Crank arm length has nothing to do with feeling like you're standing high over your bike.

i agree crank length doesnt change ride height...
but it does affect stance, which changes your center of gravity, which effectively feels like you are lower on the bike, really you are just squatted down a little more since feet spread out a little further

real short cranks make me feel like i am stood up tall on the bike, longer cranks let me spread my feet and feel more sunk into it, i find my happy place on 170s, longer puts my toes into the wheel, shorter feels wrong

tall bars and some bb drop on the frame make more of a difference for sure, but crank length can play a subtle part in the discussion imo

Posted: Dec 3, 2017 at 22:45 Quote
cmc4130 wrote:
adrennan wrote:
since you should have your cranks level while riding, longer cranks wont really change anything in terms of "ride height"

Yeah, I agree. Crank arm length has nothing to do with feeling like you're standing high over your bike. There's actually a trend in BMX and DJ in favor of shorter cranks (closer stance, plus more room for barspins on 26").

If you feel like you're leaning/hunching down too much, you may benefit from taller bars. Like, a lot taller.

What stem, bars, and fork do you have?

I personally like a taller setup, (6'1", long legs). 4" rise bars with an 80mm travel fork (sort equivalent to 3" rise bars and a 100 mm fork).



STOUT Bikes currently has some 4.5" rise bars https://www.pinkbike.com/u/mattty/

Otherwise, Atomlab 3" PimpLite risers combined with top load or riser stem....


I'm currently set up with I think 35-40mm rise (cant remember exactly) 40mm stem and 100mm circus. I added about a half inch to inch rise above headset with spacers awhile back, and maybe I need to bring it up a bit more, or get some higher bars.......or maybe just maybe get off my dh and ride the dj until I stop feeling kinda squirly on it.....
Those bars on your dj are sick. Are those the stout bars you referring too?

Posted: Dec 3, 2017 at 22:54 Quote
Aaronz25RS wrote:
Strange, the Tweet is considered a DJ and with a 69 HT angle, it should really have a negative BB (below axle line) but I couldn't find BB height spec quickly. .

I've never studied enough geo info to know what I need, i have always just made tweaks to builds to fit my riding style. Just out of curiosity what should I be looking for geo wise when I'm spec'n out a dj? I've hit some decent size features with the bike, but it always felt kinda forced and squirly with the tweet.

Posted: Dec 4, 2017 at 7:14 Quote
Aaronz25RS wrote:
Strange, the Tweet is considered a DJ and with a 69 HT angle, it should really have a negative BB (below axle line) but I couldn't find BB height spec quickly. .

In this Spank Tweet Tweet photo, it does look like the bottom bracket is on the line between the wheel axles (i.e. zero bb drop). A lot of BMX race 24"s (cruisers) are designed that way (or bb slightly above axle level, like 12.25"). However, with 20" BMX, the bottom bracket is around 1.75" above axle level. Historically, that was because 20" wheel bikes in the 1960s, 1970s like Schwinn Stingrays had short cranks (and a bb at axle level), but when taller riders wanted longer cranks, then they needed ground clearance to prevent pedal strikes when cranking in a turn.

So, the rider is effectively standing higher in the bike. Taller bars will def balance out the feeling.

http://plussizebmx.squarespace.com/blog/tag/tweet-tweet




Posted: Dec 4, 2017 at 7:20 Quote
funkytrailjunky wrote:
Those bars on your dj are sick. Are those the stout bars you referring too?

They're actually Immortis Bucket bars. But, I don't think they're made anymore. http://immortisbmx.bigcartel.com/product/2010-immortis-bucket-bars

They were inspired by S&M C4 bars. http://bmxmuseum.com/forsale/108268

Here's another STOUT bar:

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