Personally - I think this would be awesome....with one change. I really like slack bikes. I'd go with a 70 or even a 69 deg head angle. Before evryone freaks out and say that is stupid, my last 29er was a non-suspension corrected frame - I stuck a Reba on there at 100mm and the thing was absolutely amazing. BB was just a hair over 13 and front end was super slack. I was able to take lines on that bike that I am nervous to on my 5.5 in travel 26 FS. For me and my local trails (rocky) - slack works really really well.
29er Woods bike Geometry Musings - what do you think??
Okay,
What do you guys think of a frame set up like this - sort of like a 29er "woods" bike if you will:
1. Seat tube angle 72.5 degrees
2. Head tube angle of 71 degrees with a 4" fork up front (Reba I guess)
3. 16.9" chainstays (possibly a hair shorter as I'd be running this single speed)
4. 23" or 23.25" Effective Top Tube length (with a nice slope to it, maybe even with an evil sovereign like brace on it)
5. 16" or so seat tube with a long post
5. but here's the kicker - a high bottom bracket - say 13.5"
How do you think something like that would ride?? Would the higher bottom bracket help make it easier to loft the front end up over or up on to logs or rocks and whatnot?
The short stays would help keep the rear wheel under me when I was standing and climbing right?
Just for reference - I selected that ETT length based on my previous (and current bikes) and my 5'9" height.
Whattya think???
What do you guys think of a frame set up like this - sort of like a 29er "woods" bike if you will:
1. Seat tube angle 72.5 degrees
2. Head tube angle of 71 degrees with a 4" fork up front (Reba I guess)
3. 16.9" chainstays (possibly a hair shorter as I'd be running this single speed)
4. 23" or 23.25" Effective Top Tube length (with a nice slope to it, maybe even with an evil sovereign like brace on it)
5. 16" or so seat tube with a long post
5. but here's the kicker - a high bottom bracket - say 13.5"
How do you think something like that would ride?? Would the higher bottom bracket help make it easier to loft the front end up over or up on to logs or rocks and whatnot?
The short stays would help keep the rear wheel under me when I was standing and climbing right?
Just for reference - I selected that ETT length based on my previous (and current bikes) and my 5'9" height.
Whattya think???
1 - 20 of 87 Posts
I was pondering going to 70 degrees with the HT angle
What was the frame that youput the Reba on? I'd love to know.
What was the frame that youput the Reba on? I'd love to know.
You're not too far off from where I'd want to be. I like the slightly slack STA, and the 71* HTA is pretty much the only choice for us shorter folks. 16.9" chainstays are awesome if you can get them that short. TT length is a bit long for me, but I know you're a couple inches taller than me, so that makes sense. ST length is fine.
Not sure about the BB height though. And I say that as a tall-BB fan: with the EBB set where I like it, my Vulture's up somewhere in the neighborhood of 12.8". I like (make that need) the extra pedal and chainring clearance, and I don't find that it compromises handling. But if you go too high you can run into TT clearance issues, and the higher the BB is the harder it is to get on and off the bike in rugged terrain. Also, a higher BB makes lofting the front end easier, but by the same token it also makes endos easier -- the larger BB drop is the main reason 29"ers are more endo proof than 26"ers. I just don't know how tall is too tall: 12.8" is great (for me). 14" is probably too high. Is 13.5" too high? I really can't say for sure. I know Shiggy prefers a BB height in that range.
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EDIT: just read the above exchange about slacking out the HTA. By "woods bike," I assume you mean something that handles well on the famously tight twisty singletrack of New England. I had my Vulture designed specifically for tight/twisty (Northwest) terrain, and personally I would NOT want to slack out the head angle beyond 71 degrees -- unless I were specifically planning on using one of the new longer-offset forks coming our way. Then 70 ish would be fine, and 70* combined with extra fork offset would certainly avoid any toe overlap issues. You will get a slightly longer wheelbase that way, but except in extremely tight singletrack it shouldn't be a disadvantage.
Not sure about the BB height though. And I say that as a tall-BB fan: with the EBB set where I like it, my Vulture's up somewhere in the neighborhood of 12.8". I like (make that need) the extra pedal and chainring clearance, and I don't find that it compromises handling. But if you go too high you can run into TT clearance issues, and the higher the BB is the harder it is to get on and off the bike in rugged terrain. Also, a higher BB makes lofting the front end easier, but by the same token it also makes endos easier -- the larger BB drop is the main reason 29"ers are more endo proof than 26"ers. I just don't know how tall is too tall: 12.8" is great (for me). 14" is probably too high. Is 13.5" too high? I really can't say for sure. I know Shiggy prefers a BB height in that range.
---
EDIT: just read the above exchange about slacking out the HTA. By "woods bike," I assume you mean something that handles well on the famously tight twisty singletrack of New England. I had my Vulture designed specifically for tight/twisty (Northwest) terrain, and personally I would NOT want to slack out the head angle beyond 71 degrees -- unless I were specifically planning on using one of the new longer-offset forks coming our way. Then 70 ish would be fine, and 70* combined with extra fork offset would certainly avoid any toe overlap issues. You will get a slightly longer wheelbase that way, but except in extremely tight singletrack it shouldn't be a disadvantage.
I think a 71 degree HT angle would be fine.
Maybe drop the bb down to 13" even?
I was also toying with a 23" ETT - but added a little extra in just in case.
I would ride this as a single speed (or perhaps 1xsomething) so no need for front derailleur clearance issues.
Maybe drop the bb down to 13" even?
I was also toying with a 23" ETT - but added a little extra in just in case.
I would ride this as a single speed (or perhaps 1xsomething) so no need for front derailleur clearance issues.
Ah, but have you picked a builder yet?
You're describing the bike I want!....I think ~13" is a good bb height. I've got an Evil Sov set up as a 69er right now with a Instigator fork. BB is right @ 13". It feels just right for rocky front range trails. Don't think I'd go any higher. But i'm a leggy 6' tall and for me the bar height for singlespeeding is up pretty high.MMcG said:I think a 71 degree HT angle would be fine.
Maybe drop the bb down to 13" even?
I was also toying with a 23" ETT - but added a little extra in just in case.
I would ride this as a single speed (or perhaps 1xsomething) so no need for front derailleur clearance issues.
Yeah...I'm thinking about a 29er Evil clone bike also.
Geared or single, rigid or suspended....the versitility is great. Slack angles are good. Suppose it depends on riding style.
Any photos of your Sov set up with the Instigator fork?ripley said:You're describing the bike I want!....I think ~13" is a good bb height. I've got an Evil Sov set up as a 69er right now with a Instigator fork. BB is right @ 13". It feels just right for rocky front range trails. Don't think I'd go any higher. But i'm a leggy 6' tall and for me the bar height for singlespeeding is up pretty high.
Yeah...I'm thinking about a 29er Evil clone bike also.
Geared or single, rigid or suspended....the versitility is great. Slack angles are good. Suppose it depends on riding style.
Would you prefer a true 29er with those sort of features rather than teh 69er you've currently got?
This sounds like a perfect project for On-one.
Mark, what's the BB height on the Sinister? Isn't the Simon designed to excel at NE riding? Not saying don't go have a custom bike built or anything, but FTW's bike looks awesome. (If I hadn't bought the KULA 2-9 frame I would've tried to buy one of the prototypes). This thread is great though, I've been pondering what I'll be riding in a few years once I grow tired of riding only rigid XC race style bikes.
No pics with me...but I'll post some this wkend.MMcG said:Any photos of your Sov set up with the Instigator fork?
Would you prefer a true 29er with those sort of features rather than teh 69er you've currently got?
Good question on the 29er....i've been pondering this.
Think my 29er version will be less extreme in terms of sturdyness (evil is 6+ lb frame and is 28 lb. as built right now) and angles. Lighter weight for singlespeeding and general technical riding.
Since i'm not that hardcore of a rider (no big drops, high-speed decents, etc) I think I would like the 29er version better. The increased rollability of the rear wheel would be nice, I think. Though the Evil Sov 69er works pretty good for my style (lower speed, very technical terrain, a bit of trialsy pivoting, etc).
I need to talk with some builders to figure out what's reasonable.
Actually I've seen some Wolfhound frames posted that would seem to fit the bill.
Super short chainstays, lots of standover....
I've also been thinking about this sort of bike recently. I was using my Inbred on a trail that pretty much scared the crap out of me last weekend. The reba at 80mm together with 72 HA made me real uncomfortable ona lot of steep rollers. I was thinking about what would make me more confident riding that stuff, and first thought was a much slacker head angle. I'm going to convert the reba to 100mm for starters, but not sure how much that will actually slacken the HTA. A new offset fork should bring the handling back for very slack head angle, as someone already mentioned. I'd also need go up a tooth or two on the rear cog or go geared. The need to constantly accelerate and loft the wheel was killing me. I think a little bit higher BB and some more standover would be nice.
a "woods" style bike would be awesome around my local trails. i ride low speed trails littered with rocks and roots and lots of available stunts, and a light front end and tight wheelbase would make a really fun bike.
long answer:
i ride a med niner SIR and use a shortish stem, and just this spring finally put my handlebars a smidge above my seat. that made soo much difference i was really amazed. it made wheely drops easier and the slow speed step ups easier too.
I also run my EBB at it's highest position which is a touch over 12 inches. my wheelbase is @42inches.
if i had to buy a new bike right now i wouldn't change the angles, but i would like a touch shorter chainstay and a 1/4 - 1/2 inch higher bb. i've thought about trying to set the ebb in it's farthest back(closest to rear tire) position to see if that changes anything, but i'm afraid of the lowered hight...last year i had it close to 3 o'clock and had a rock strike that threw me down and took me off the bike for 6weeks.
long answer:
i ride a med niner SIR and use a shortish stem, and just this spring finally put my handlebars a smidge above my seat. that made soo much difference i was really amazed. it made wheely drops easier and the slow speed step ups easier too.
I also run my EBB at it's highest position which is a touch over 12 inches. my wheelbase is @42inches.
if i had to buy a new bike right now i wouldn't change the angles, but i would like a touch shorter chainstay and a 1/4 - 1/2 inch higher bb. i've thought about trying to set the ebb in it's farthest back(closest to rear tire) position to see if that changes anything, but i'm afraid of the lowered hight...last year i had it close to 3 o'clock and had a rock strike that threw me down and took me off the bike for 6weeks.
sounds like a nice ride MMcG...but i'd slack the STA more (maybe 70/71). i like the long-ish (17.5) chainstays for 29er, helps add to the invincible downhill stability of these monsters and on an SS you're standing and climbing anyways, plus the wheels are so traction already. but i think you are right on for the higher BB, i'd love a 13-13.5, i'm used to pretty high BB's on all my rides.
and a true 130mm fork, i know we've all been waiting on that one.
and a true 130mm fork, i know we've all been waiting on that one.
The sinister bottom bracket height is sub 12" - 11.75" I think. I think they shoulda gone higher, but that's just my opinion and I'm no frame builder like FTW.mtbdee said:Mark, what's the BB height on the Sinister? Isn't the Simon designed to excel at NE riding? Not saying don't go have a custom bike built or anything, but FTW's bike looks awesome. (If I hadn't bought the KULA 2-9 frame I would've tried to buy one of the prototypes). This thread is great though, I've been pondering what I'll be riding in a few years once I grow tired of riding only rigid XC race style bikes.
yeah - i guess we are on opposite ends of the bb height spectrum. I still can't see how you aren't going to get a lot of pedal strikes with that low of a bottom bracket.
My Karate Monkey had an 11.5" bb height and it sucked big time around here for woodsy trail riding.
My Karate Monkey had an 11.5" bb height and it sucked big time around here for woodsy trail riding.
Were you running it full rigid?
I will likely get some pedal strikes...however, you adapt to it & the low bb is definitely worth it to me.
I will likely get some pedal strikes...however, you adapt to it & the low bb is definitely worth it to me.
I ran it both rigid and with a reba - didn't matter either way.
I still get a few with the 12" bb height on my inbred
I'd like to learn more about bb height but I don't see me going any lower than 12 ever again, and bumping it up above to the 13" range is very intriguing to me.
What exactly is it about the low bb that is attractive to you? The ability to corner tightly on the bike?
I still get a few with the 12" bb height on my inbred
I'd like to learn more about bb height but I don't see me going any lower than 12 ever again, and bumping it up above to the 13" range is very intriguing to me.
What exactly is it about the low bb that is attractive to you? The ability to corner tightly on the bike?
A low bb bike just flat out rails. I have never been able to get used to the feeling of a high bb bike....I would rather run a shorter crank arm & drop the bb. ymmv
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