That was your point?
funnily enough if I'm riding DH I'll use my DH bike but this isn't a thread about DH bikes.
an AM bike you'd like a company to build
- Thread starter saruti
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funnily enough if I'm riding DH I'll use my DH bike but this isn't a thread about DH bikes.
I wanna see what trails you guys are riding where you would want sub 67* HA. My last trail bike was 66* and it was a pain in the ass on climbs. If it wasn't 23.5lbs I would have hated climbing.
matt, what bike was it?
Yeti ASR5-Carbon with a 150mm fork. Fantastic bike but I had to completely change the way I climbed because of the head angle. If I didn't get my whole body over the front tire it would wonder all over the trail and lift off from the smallest bumps. I couldn't imagine trying to climb with 63-64 HAs like some of you are suggesting.
I guess if you just had fireroad climbs and long extended descents it might work...
the ones where i live have super steep climbs, mostly fireroads, and long DH descents and I don't have a problem climbing with a sub 66*HA. My Hardtail has a sub 65*ha (ragley blue pig with 150mm lyric) and i don't have a problem climbing anything on it, either.
For the record, ° is <alt>0176 
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The commencal guys already made it!
Awesome looking bike IMO. I wonder if one with air suspension, an adjustable fork, and a dropper would be worth a crap for AM?
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Seat angle makes far more of a difference in keeping the front end down than head angle does. My Enduro is a 66 head angle with low 16 in long stays and it has no trouble keeping front down with a 74 degree effective seat angle. The Yeti has a 71 degree with a 140mm fork and depending on which 150mm fork you could have had a significantly taller axle to crown and maybe even less than 70 degree. That was almost assuredly the culprit.
He had a revelation at 150 which is about 20mm higher than a fox set to 140. I own the same bike, and I am sure it was a beast to climb with that fork on there due to the seat angle and high front end. I have a fox set to 135mm on my asr 5, and it feels balanced and handles great both up and down. So, you are right, overall geometry does make a difference. That said, a 67 head angle is as slack as I go for my trailbike. I just ride too much tight twisty singletrack to want it any slacker for up or down.
I will agree on the agility gain from the steeper angles for sure. My trails are super fast and off camber wide open sort of thing for the most part intermixed with occasional steep rock rolls and short spurts of fun lines so I like my enduro's angles and I LOVE the super short stays for the playful nature they provide.
I personally don't understand why more bike manufacturers don't run steeper seat angles. I bought a Pivot 5.7 and promptly returned it when I couldn't work with the seat angle. Chris said that it was because DW sits higher in its travel but I couldn't get happy with my pedaling position. Am I an anomoly in this regard as angles are kind of all over the spectrum?
I never gave too much thought to the seat angle being changed by the longer A2C measure of the fork. I also have a long inseam so my seat was jacked up really high, probably exasperating the poor climbing ability I noticed. Jeremy is spot on with the Yeti feeling best around 130, I dropped the Fork down to 130mm for a short time before my injury and the bike was a lot more playful.
SoCal, our trails go very steep up and very steep down. Meadows in Aliso Woods, for example, about as steep a climb as possible on a bike. Aenema has it, seat tube angle is more important than head angle for maintain traction and not looping out.
Ah, this thread has come around and I now have cohorts who want steep seat tube angles. Any bike companies listening? We'd like our seats in a reasonable position when dropped and then a standard xc position when raised that doesn't place our weight behind the rear wheel.
I am with the folks that feel changing just the head angle alone doesn't change climbing behavior that much. I went with a 1.5° reducer headset on my AM bike. I could feel the change in wheelbase but the front end wasn't any more likely to wander or lift when climbing.
I bought a 98 Specialized Ground Control last fall because of how it rides. Its amazing, corners so fast, climbs well, eats up everything but the biggest hits (has even taken a 35ft gap). I have a decent component spec on it, just need a disc conversion and maybe a fox 32 and it will dialed. The only complaint I have about it is the lack of seat post adjustability, but I can live with it. Wouldnt trade it for anything.....except maybe a Dixon.
definitely AM, you would be surprised if you knew how many good trails there are in this area. this is just a section of a trail that is popular, it's a 2 way trail and gets climbed a bunch, it's not steep compared to other trails. Then, we have a bunch of trails that are downhill only but are accessed by long, steep fire roads.
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Titus FTM looks nice. Made in the USA and only $899 without shock!
http://dev.titusti.com/bikes/trail/ftm/
135mm travel
140-150mm fork
5.75 lbs claimed weight w/ shock
30.9mm seat tube so you can use a dropper post
69.25° head tube
71.75° seat tube
13.25" bb height
The head tube angle is steep, but it probably uses 6mm shock hardware so some offset shock bushings should get that down to 68° which I think is good for a trail bike. It also uses a ZS44/EC49 headset size so you might still be able to use a tapered steerer fork with an angleset to get the head tube angle down to 66.5° and the bb height down below 13".
No ISCG mounts though.
http://dev.titusti.com/bikes/trail/ftm/
135mm travel
140-150mm fork
5.75 lbs claimed weight w/ shock
30.9mm seat tube so you can use a dropper post
69.25° head tube
71.75° seat tube
13.25" bb height
The head tube angle is steep, but it probably uses 6mm shock hardware so some offset shock bushings should get that down to 68° which I think is good for a trail bike. It also uses a ZS44/EC49 headset size so you might still be able to use a tapered steerer fork with an angleset to get the head tube angle down to 66.5° and the bb height down below 13".
No ISCG mounts though.
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I had one in college, it was Ok. The bike was a little too DH to be good at XC/AM and a little too much XC/AM to be good at full blown DH. It was good for pedalling out to sections of trails and sessioning them but for extended XC rides it was a pig. I think it came in around 35-36lbs.The commencal guys already made it!
Awesome looking bike IMO. I wonder if one with air suspension, an adjustable fork, and a dropper would be worth a crap for AM?
sidenote: Look at that sweet rack I made for my truck, miss that thing...
Well after the First 5 DH bikes are finished my plan is to build an AM bike. I think the Alfine Di2 would be perfect. Still the same full internal driveline and shock design as the DH bike. Lower pivot, and integrated drop post. I can't see the need for more than 6 speeds on a DH bike. But on a AM bike 11 should be great. And the Geo debate on this thread has been quite helpfull. Thanks
Just an update on what I have found. Doing some more digging on a bike with short enough travel to feel responsive and nimble, be able to run a longer travel fok, meet the geo requirments and currently for me a frame with a reasonable price tag. I just stumbled on the Devinci Dixon. Yes I know its been out a while but I thought it had a higher price than the one I just found, which happens to be on sale too. I also thought it was 160mm of travel. The only Neg I have is the longer than normal Seat tube of 19.5" on a large, so my seat will be slammed for the downs and jumps. BB is not super low, HA is acceptable at 67*, chainstays come in at a nice sub 17". Seems to build down to a nice weight and from what I can see it can handle the required abuse. This may be the bike if I can get it at the current price.