Posts
342
Joined
9/6/2015
Location
Menifee, CA
US
Edited Date/Time
9/14/2022 11:19am
OK, weird MX guy asking a bicycle question here. Why do all MTBs have neck-breakingly low handlebar heights? Even with 30-35mm riser bars, I feel like I'm craning my neck to see more than 3 feet ahead of my front tire. I am 6'1" on a large Commencal Meta. I feel like the bike is the right size for me. Even if it isn't, all bikes I ride feel similar, from this complaint's perspective.
When I ride my MX motorcycle, a seated position puts my grips about on the level with my ribs. On a bike, they are at my hips or lower. I could, in all honesty, benefit from about 4-5" more handlebar height, just for neck comfort. (Not to mention descending capability.)
I get that MTB has sort of grown organically from road bikes to XC to what we have now, but at least in the disciplines of Enduro and Downhill, wouldn't it be OK to sit more upright? I'm surprised the MTB geometry evolution hasn't gone in that direction.
Can somebody please design and test an enduro bike with about the same geo, but a much taller stack height, please???
When I ride my MX motorcycle, a seated position puts my grips about on the level with my ribs. On a bike, they are at my hips or lower. I could, in all honesty, benefit from about 4-5" more handlebar height, just for neck comfort. (Not to mention descending capability.)
I get that MTB has sort of grown organically from road bikes to XC to what we have now, but at least in the disciplines of Enduro and Downhill, wouldn't it be OK to sit more upright? I'm surprised the MTB geometry evolution hasn't gone in that direction.
Can somebody please design and test an enduro bike with about the same geo, but a much taller stack height, please???
I'm MTB having dabbled briefly in moto with an XR 100 and have never seat bounced in my life. But I certainly didn't find myself with more vision on a moto.
https://nsmb.com/articles/fit-before-fashion-protapers-76mm-riser-bar/
So I guess what I'm getting at is... Do what YOU like. Trends are just that, temporary trends and not rules. A higher bar and slightly longer stem are cheeper than a new fork or crown and steerer assembly. So just try it out. If it doesn't work out just build a dirt jumper or "Pump track bike." around your new bars!
I really might try those.
tl;dr is pretty much what @Falcon said. Climbing steep stuff would be trickier, a little (or a lot) less grip in corners and a more upright position overall.
Some of it you can adjust for w/ body position but that can lead to other issues.
I ended up going from a 130mm fork w/ 35mm stem and 780 bars to a 150mm fork w/ a 50mm stem and 740mm bars to get the position and bike handling I wanted.
I remember a number of years ago it was common to see large, machined spacers under the stem and high rise bars on the pro's bikes in the World Cup bike checks. Then it became the cool thing to put the bars as low as possible with the argument that it puts you into an aggressive, attack position. But I don't believe there was much if any data used to make that claim. Then again, I no longer believe that there is much experimentation/data used for anything in mountain bike design, just trend chasing that sometimes takes bike design in the right direction, but quite by accident.
I don't know much about moto. Is there a need to shift weight forward to get the front wheel to bite in corners? Or is such body english futile relative to the weight and power of the bike?
Personally I prefer something somewhere in between. I can ride a bike with pretty much any height stack and get used to it though. Stand over on the other hand needs to be lower on so many bikes. I get that suspension and seat tube angles limit a lot of peoples designs but I absolutely will never buy a bike with anything but super low standover again. I never realized my seat was in the way till I rode a transition and I can’t go back now.
Can someone do the math here?
1) the higher the handlebars are, the farther you have to effectively lean over when cornering. The only way you would really be able to have bars at a similar height to your moto’s is if you rode it like a moto and lean more with your body, and less with the bike. This would require trails to be quite a lot different than they mostly are.
2) Fitting and body measurements. There is a whole other side of science that I don’t know enough to teach about but know enough to get me in trouble. There is an optimal position unique to you that your body can function best in. From working with a bike fitter your handlebar height usually depends on your lower back and neck flexibility, as well as your proper saddle height. All I can say is have your pedaling position looked at by an expert in bike fitting and they can definitely help you look farther ahead. From your description you might be a little on the tall side for a large meta depending on the year.
3) maneuverability. Bikes are designed to be good at both going uphill, and downhill. If you look at modern DH bikes, they are not meant to climb at all so the bars can be a little bit higher to help you go downhill with more confidence. While on the other end of the scale, XC bikes have much lower bar heights to help keep weight on the front wheel so that you don’t wheelie or loop out as soon as the trail points up. The Meta sits almost exactly in the middle so does require a lower bar height, but when the seat is dropped, the bars effectively feel higher.
Yes, while climbing I tend to look a lot closer to my wheel than I do descending, but that is only because I am leaned farther forward due to the increased saddle height.
I use 1.25-1.5 inches of spacers(depending on bike) as well as 50mm rise bars and it feels great.
On my size M Timberjack hardtail, I overforked it from 120mm to 160mm and use 1.25" of spacers and 50mm rise bars. I had to switch from a 50mm stem to a 10x70 stem and slide the seat most of the way forward to compensate for the weight shift to the rear on all of that. It still climbs well, but it's no CC race bike.
On my size L FS (Ripmo), I'm running a 35mm DMR Defy stem, so that lifts up the bars a lot and it has 1.5" spacers and 50mm rise bars. The seat is in pretty neutral position.
Both of my bikes climb well, but both require a little bit of body positioning on really steep climbs in order to keep the front end planted...the hardtail more so than the FS due to the overforking.
You have to be very careful about the front end getting too light for climbing. There's a lot of mass in your upper body and how much you lean forward or sit up shifts the weight around significantly.
I never really think about pushing into the bars in a corner on my moto. I always think about it on my mtn bike. YMMV (based on reach/CSs etc)
I also have put my bike on scales to prove this point. The only way to properly weight the bike when the reach/CS measurement is a certain ratio is by weighting your hands. I've posted a bazillion times about this.
See Also: The internet was wrong, short chainstays suck.
I also acknowledge that weighting in a corner is different from weighting on a straight, but wonder if we would be better off with bikes balanced so that's not necessary. Interested to hear your thoughts!
1. 29ers have taller front ends. Someone mentioned that as reach lengths got longer, WC pro's started lowering their handlebars. That's actually not true. It might look like pro's front ends are coming down because we see lower rise bars and fewer stem spacers, but that's because with 27.5 & 29" wheels, frame stack heights have gotten higher. A 29" front wheel and fork is 2" higher than a 26" frame and fork. That's part of the reason why a lot of companies are speccing stupid short head tubes on their 29er frames. There was a trend in the mid-2000's for WC pro's to run low bars (Sam Hill famously took the top cap off his headset to minimize cockpit height), but bars went up in the pro ranks around 2010 and they haven't gone down since. Going downhill, taller really is better. Modern 29er downhill bikes might look like their bars are lower, but they're actually as high or higher.
2. Good descending position depends on where you ride. As discussed above, the steeper your trails are, the taller your bars need to be for descending and you'll just need to put up with steep bars on your way back up the hill. But the inverse is that, the flatter your trails are, the lower you need your bars to be to weight the front wheel and give you a reasonable range of motion over the front of the bike. To answer the OP, if trail/enduro/all mountain bikes were only made for gnarly riders in Squamish, BC, the stack heights would be higher. But bike companies also sell aggressive full-suspension bikes to Jerry's in Indiana and to old/slow/ignorant riders in my neck of the woods who choose to compromise their descending position to get better pedaling characteristics. For a local example, if you're selling a 160mm travel enduro bike to someone who only rides at Duthie, they're going to be pissed about a high stack height because... Duthie is flat.
3. Inseam height affects bar height. Riders with tall legs and short torsos will need higher bars. For instance, Jack Moir runs short frames with really tall bars, and so do I. I'm 6'3" with long legs and I chose the 490mm reach XL Megatower over the 515mm reach XXL frame. I'm happy as a clam with that decision. Riders hinge at the hips to reach the bars, and the higher your hips, the higher your bars need to be. The opposite is true for riders with short legs and long torsos- they will need lower bar heights. Our recent senior men's world champion is a great example of this body type, and as a result Reece Wilson runs low rise bars and no stem spacers on his Trek. If you're a frame manufacturer, is your size large frame designed for 6'2" riders with long legs and short torsos who want a long head tube, or is it designed for 5'10" riders with long torsos and short legs who need a short head tube? It's made for both, so frame manufacturers play it safe and spec a shorter head tube. That means guys like me and Jack Moir end up running tall bars and a grip of stem spacers.
I know nothing about Motos, so I have nothing to contribute to that side of the discussion.
Post a reply to: Another geo thread - this time, related to stack height