"New" Geometry

fos'l

fos'l

Well-Known Member
My wife and I had been riding our SC Superlites, 12 and 16 years old until her bike was stolen a few months ago and replaced with a new generation 29er FS. Her speeds both uphill and down have increased markedly. Are the new designs that much better or is it 26 vs 29 that prevail?
 
I think the newer geometry makes a huge difference. I have easily helped/went with 25-30 friends buying new bikes, 3 here in Prescott in the last couple months, and they are all amazed at how well the new bikes ride. One guy who was already a solid climber on his 2017 Giant Trance is now leaps & bounds faster on his 2021 Pivot Trail 429 'Enduro' model. If that bike didn't have 157 wheel spacing, it may be my next frame purchase. It rides like a dream.
 
fos'l said:
My wife and I had been riding our SC Superlites, 12 and 16 years old until her bike was stolen a few months ago and replaced with a new generation 29er FS. Her speeds both uphill and down have increased markedly. Are the new designs that much better or is it 26 vs 29 that prevail?
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The new geo has done a ton for mtb. When was the last time I went otb? Years ago! Much more stable because of extended wheel bases. Slacker head angles make it harder to go otb too. Lower bottom brackets for better cornering and bike maneuvering. It also lets you get lower to the bike for the tech. Lower seat tubes also aid in this assuming you have a dropper post. Steeper seat tube angles get you over the pedals so you use more of the legs and less of the lower back for pedaling. A properly set up 29r makes all of this work for me so I can get up to speed and roll over stuff better. My biggest problem was getting used to the low BB height. I like techy climbs so pedal strikes are a major bummer. Also going to wide flat pedals just about killed me! Talk about pedal strikes! Back to geo , 27.5 with the new geo will generally be a bit easier to maneuver. Do not go too slack though. The slackness of your head tube should match your terrain preference. I do find that there are specific instances where the chopper affect can be a bit sketchy . So just some random thoughts about geo. Get out and demo. The guys on this sight can lead you to shops that demo. Just throw it out there.
Go ride one.
TTB
 
Thanks everyone. My friend, a fairly successful racer, said the new geometry is a "game changer". Sometimes, what's good for excellent riders isn't great for me. Glad to hear even a snail can benefit. The quest begins. Sorry, old paint, but you did a good job for 17 years.
 
One last question. Looking at 29er's geometry for current models and most seem to have the dimensions within one cm of my 2007 (?) Niner One9 (XL). Are the new hardtails still much more refined?
 
fos'l said:
One last question. Looking at 29er's geometry for current models and most seem to have the dimensions within one cm of my 2007 (?) Niner One9 (XL). Are the new hardtails still much more refined?
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Depends what you are looking at, if looking at XC, the difference may not be as big (68 69 degree head angle), relatively shorter reach..
The biggest changes would be seen in more trail oriented hardtails where 66 degree head angles are about the average
 
fos'l said:
One last question. Looking at 29er's geometry for current models and most seem to have the dimensions within one cm of my 2007 (?) Niner One9 (XL). Are the new hardtails still much more refined?
Click to expand...


Your One9 had very steep geometry in 2007....it took Niner a lot of years to get out of that rut. I will give them that they had long top tubes for the era, but the HA's were stupid steep.

Modern hardtails are much more refined. Aluminum frames ride much nicer these days. They are no longer the super stiff bone jarring rides they used to be. Guess the manufacturers finally figured out how to design in a little bit of forgiveness.
 
Today my wife and I were ascending Skully Hill instead of the more user friendly Skully Ridge; the main problem for me with my 2005 SC Suprelite is the front end wanders and I need to use already depleted resources to get back on the trail (not a problem for you young studs, but I'm old). The new bikes I've been looking at have slacker head and seat angles than my bike. Will this exacerbate the problem?
 
fos'l said:
Today my wife and I were ascending Skully Hill instead of the more user friendly Skully Ridge; the main problem for me with my 2005 SC Suprelite is the front end wanders and I need to use already depleted resources to get back on the trail (not a problem for you young studs, but I'm old). The new bikes I've been looking at have slacker head and seat angles than my bike. Will this exacerbate the problem?
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Yes and no.

The slacker the HTA, the more the front tire is going to wander when climbing....and more so the steeper the climb.

However, the steeper STA will help to counteract that a little bit by moving you more over the BB.
 
fos'l said:
Today my wife and I were ascending Skully Hill instead of the more user friendly Skully Ridge; the main problem for me with my 2005 SC Suprelite is the front end wanders and I need to use already depleted resources to get back on the trail (not a problem for you young studs, but I'm old). The new bikes I've been looking at have slacker head and seat angles than my bike. Will this exacerbate the problem?
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I doubt the new bikes have a slacker seat tube angle. They tend to be much steeper than anything prior to about 2017. Your Superlight was probably 71°. Most new bikes slot in around 75-77° effective seat tube angle. As J said, that helps a bit with the slacker front end.

But, yes a slacker, higher front end will wander more than a lower, steeper front end. Those of us who regularly climb slack bikes (mine is about 64°) just keep the chest down more when it gets steep. And the saddle nose up yer sphincter! Or - just avoid climbing! :thumbsup:
 
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Thanks; that's the way it seems to me (and see what you mean about the effective seat tube angle). I'd give up climbing except it's not called Chino Flats State Park. You seem damned if you do or don't since my breathing seems affected if I hunker down. Problems only an octogenarian could love.
 
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Thanks again all who answered. I had a chance to ride a newer FS, and ascents were more challenging for me than older designs, but I'm not abandoning the concept. This weekend I'll try a difficult (for me) ascent on my 15 or so year old Niner hardtail. This may be the best bike for my aging legs.
 
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