Wide bars

batmo

This equation should allow you to calculate the angular momentum of any bar and stem combination:

bennett_346

Are you for real?

cooldad

Maths fail anyway unless you state what the letters refer to. I suspect a refugee from the commuting forum.

batmo

bennett_346 wrote:

Are you for real?

No, not at all!

The last time I replaced my bars, I fitted them un-trimmed and just moved brake levers and shifters until it felt good.

mcnultycop

I went from 620/110 to 705/60. It just felt a load better for me as I have broad shoulders.

It does seem that people tend to just recommend wider bars and a shorter stem as a matter of course, and it isn't right for everyone.

crispy1980

Just to add to this I fancy doing the sane. Shorter stem and wider bars, but, what differencedoes it make if you have a stem with a higher rose than the norm? I have just used the shim on my spesh to change the stem angle from 8 degree to 16 degree rise and it feels much better. As a shorter stem should sit me up slightly do I go for the dame rise or less? What effect is this likely to have?

BlueAdvocate

Run 750/50 bar/stem on my Remedy and love them. Twitchy on a climb but the biggest improvements I could make to climbing is getting fitting and losing weight. Downhill much better. As people have stated its a personal preference and what suits the rider. Stem lengths are interesting in that why have long stems, get the steering over/as near as the point of turning as possible.

Dirtydog11

Batmo wrote:

This equation should allow you to calculate the angular momentum of any bar and stem combination:

I reckon that would be a good idea if it where made into a spreadsheet, you could enter your current setup (stem and bar length) and your new setup, you would then be able to see the % difference between the two, it would be good for reference and when matching different bar stem combos.

Who's good with with spreadsheets and equations?

bennett_346

Surely It would be easier just to express the % difference between the two as a percentage increase on the width as opposed to your current bars, as the rest of that equation would just be a constant...

lostboysaint

bennett_346 wrote:

Surely It would be easier just to express the % difference between the two as a percentage increase on the width as opposed to your current bars, as the rest of that equation would just be a constant...

Depends if you're shortening your stem as well, which is generally the way it works to keep reach around the same.

Dirtydog11

For example,

You may be happy with your current setup (steering response) but want to fit a shorter/longer stem, the question is if you fit the shorter/longer stem what width bars do you need to fit to maintain the same steering characteristics?

Same goes for a change in bar width!

That equation's Greek to me.

Northwind

Dirtydog11 wrote:

Who's good with with spreadsheets and equations?

Can anyone put "Fanny about with it til it feels good" into a spreadsheet for me?

justwan naride

On my xc/trail ht, I've gone from stock 100mm/620mm (waaay to long stem for a small sized bike) to 80mm/620mm and finally 40mm/700mm (that's stem/bars). I'm 1.65m so 700mm is wide for me but it's one of the best changes I've made to the bike. Way more control in the bumpy stuff. Ideally I'd go for 720 (tried it and loved it) but some of my regular singletrack goes through very tightly spaced trees. First time on the new bars my little fingers went through a lot of pain. Riding my mates ht with 660mm bars feels weird now but bearable. Anything narrower and I feel I don't have any directional control of the bike.

The very short stem gives me plenty of room to use body language and has moved my centre of gravity a bit towards the back, which makes a significant difference when descending. For longer xc rides it can feel a bit short, 60mm would be a better fit, but in anything remotely technical I'm loving it. Even 10mm makes a difference in stem length.

Climbing hasn't been negatively affected by this and I enjoy steep climbs. Just have to sit a bit further front on the saddle. Changing to a lighter fork and front tyre did seem to make it a bit harder to keep the front down though, albeit in very steep trails.

DCR00

the width of the bar makes little difference to reach at the kinds of widths we are discussing

as for the argument around narrower bars being faster and wider bars being slower, imagine the turning of the bar creating an imaginary circle. A wider bar will create a larger circle, whilst the narrower a smaller circle. By this notion you have to cover a bigger distance using the wider bars to complete a whole circle versus the narrower bars, hence the narrower bar makes your steering faster. The same principal applies to the stem, but from a different angle.

Hence if you team a short stem and a narrow handlebar, your steering will be ultra quick

What you have to be careful of is the effect of stem length on weight distribution. On a slacker bike, where trail is generally greater, moving you back a bit on the bike using a shorter stem makes little difference to grip at the front end, but sticking a shorter stem on a steep bike, where trail is narrower, risks un-weighting the front end too much and you lose grip. Hence why i have stuck with a 90mm stem on my Spesh.

There are a few sites that explain this quite well (prob better than i have done)

But at the end of the day, what suits me wont suit you. Took me two sets of bars and 4 stems to get the right set up for me.

DCR00

Dirtydog11 wrote:

For example,

You may be happy with your current setup (steering response) but want to fit a shorter/longer stem, the question is if you fit the shorter/longer stem what width bars do you need to fit to maintain the same steering characteristics?

Same goes for a change in bar width!

That equation's Greek to me.

if you are happy with your set up, why would you want to change something ?

Dirtydog11

DCR00 wrote:

Dirtydog11 wrote:

For example,

You may be happy with your current setup (steering response) but want to fit a shorter/longer stem, the question is if you fit the shorter/longer stem what width bars do you need to fit to maintain the same steering characteristics?

Same goes for a change in bar width!

That equation's Greek to me.

if you are happy with your set up, why would you want to change something ?

Happy with steering resonse!

However you may wish to fit a shorter stem in order to move your weight back or perhaps a longer one to help prevent front wheel lift on climbs.

vonbonbon

DCR00 wrote:

On a slacker bike, where trail is generally greater, moving you back a bit on the bike using a shorter stem makes little difference to grip at the front end, but sticking a shorter stem on a steep bike, where trail is narrower, risks un-weighting the front end too much and you lose grip. Hence why i have stuck with a 90mm stem on my Spesh.

There are a few sites that explain this quite well (prob better than i have

What do you mean by slack and trail and steep? I'm still trying to get to gripsvwith the terminology.

Ta

The Rookie

It refers to the headtube angle (the angle it makes to the horizontal) 70-71 degrees is quite steep and would be used on an XC bike, the steering has less self centering and fells faster and more responsive, a slacker bike will be around 68 degrees (as little as 65 on dedicated downhill bikes) - yes small angles make that much difference. Simplistically Trail refers to how far ahead of the head tube the front axle is, 'narrower' whould normally be called shorter, a steep bike has less trail (shorter).

vonbonbon

Thanks, that makes sense. I have put a 50mm stem on my rockhopper which mostly feels great, but the front end is a little lose in corners sometimes and that explains it.

Dannyboy95

anal tightening may occur during tight woody Sections....But...

hahahah still giggling like a school girl!

lawman

The Beginner wrote:

It refers to the headtube angle (the angle it makes to the horizontal) 70-71 degrees is quite steep and would be used on an XC bike, the steering has less self centering and fells faster and more responsive, a slacker bike will be around 68 degrees (as little as 65 on dedicated downhill bikes) - yes small angles make that much difference. Simplistically Trail refers to how far ahead of the head tube the front axle is, 'narrower' whould normally be called shorter, a steep bike has less trail (shorter).

I'd call 68 degrees reasonably steep the trend nowadays is even on mid travel, 120mm bikes for slacker angles, the old whyte t-120 had a 67.5 degree headangle for example, and the 146 was even slacker, around 66 degrees. Imo, and this may be the opinion of a minority of riders, but the slacker a bike is, upto a point, the better. The 146 for me set a benchmark in bike handling though its geometry, so much so I'm essentially trying to replicate it on my HD, which with a headangle around 67.5/68 degrees is on the steeper side of the new breed of long travel, go-anywhere bikes.

Personally I see no disadvantage of a 66 degree headangle on an all-round bike, I for one would to test a light weight, circa 25/26lb, mega slack 150mm FS bike just to see how it rode!

bennett_346

lawman wrote:

Personally I see no disadvantage of a 66 degree headangle on an all-round bike

Horrible climbing? Wandering/lifting front end and poor weight distribution, and lack of cornering grip.

supersonic

Slackest I have is 69 degrees - I don't like it slacker than that for my riding. Feels too vague.

The Rookie

lawman wrote:

I for one would to test a light weight, circa 25/26lb,

Do you want light weight, or 25/26lb....25/26lb isn't light.

Northwind

bennett_346 wrote:

Horrible climbing? Wandering/lifting front end and poor weight distribution, and lack of cornering grip.

My Ragley's got a sagged headangle of 67.5, so a static of under 66 degrees, and it's possibly the best climbing bike I've ever ridden- certainly the best technical climber, though not as good a seated speedy climber as my Soda. There's a lot more to this stuff than just the head angle.

The Beginner wrote:

Do you want light weight, or 25/26lb....25/26lb isn't light.

For a 150mm travel bike that can cash its cheques?

bennett_346

Northwind wrote:

bennett_346 wrote:

Horrible climbing? Wandering/lifting front end and poor weight distribution, and lack of cornering grip.

My Ragley's got a sagged headangle of 67.5, so a static of under 66 degrees, and it's possibly the best climbing bike I've ever ridden- certainly the best technical climber, though not as good a seated speedy climber as my Soda. There's a lot more to this stuff than just the head angle.

Of course there is, but i'm not talking about them. I'm talking about head angles and thus assuming the other angles and lengths etc are constant.

Otherwise whats the point in discussing head angle?

Northwind

bennett_346 wrote:

Of course there is, but i'm not talking about them. I'm talking about head angles and thus assuming the other angles and lengths etc are constant.

Why on earth would you assume that? You made a blanket statement about slack bikes and said that they have these disadvantages.

If you change nothing but the head angle (which also means lengthening the forks incidentally) then yes, you might end up with a badly handling bike. Or, you might not. But that's not how you make a slack bike, you design it as a whole. Meaningless to talk about it in isolation.

lawman

Basically as north wind said, a bike designed around the angles and not just bodged. A 25lb 150mm bike with appropriate geometry at the slacker range of the recent trend would, if designed well as an all-round package, would be an absolute ripper both up an down. The technology and know how to do it is there, someone just needs to pluck up the balls and do it! Mondraker have gone radical, but te bikes are ugly as fook and are a touch weighty to be all rounders IMO. I think in the next 2/3 years we'll see said bike in carbon with a 1x11 drivetrain and most likely 650b too become pretty common place. Too many manufacturers playing it safe IMO. The day people start speccing 1x drive trains with guides, light weight carbon frames, dropper posts and 750mm bars as standard the world will be a better place!

supersonic

You can't really have it both ways - you design a bike with slacker geo to be stable (especially on the downs) and it suffers on the ups - at least with the way I ride. Sure recent trends have steepened the seat angle to get weight forward, but longer forks with slacker head angles have longer front centres and seem to stutter on more technical climbs, and feel vague on tight twisty single track. Is each to their own, but I value climbing and flat performance over descending and much prefer a bike designed to do so. And I am a hell of a lot faster on such a bike, even around Wharncliffe XC route. And with 635mm bars ;-). of course the light weight helps too, but some people do prefer XC based set ups, even for more 'technical riding'.

Thewaylander

supersonic wrote:

You can't really have it both ways - you design a bike with slacker geo to be stable (especially on the downs) and it suffers on the ups - at least with the way I ride. Sure recent trends have steepened the seat angle to get weight forward, but longer forks with slacker head angles have longer front centres and seem to stutter on more technical climbs, and feel vague on tight twisty single track. Is each to their own, but I value climbing and flat performance over descending and much prefer a bike designed to do so. And I am a hell of a lot faster on such a bike, even around Wharncliffe XC route. And with 635mm bars ;-). of course the light weight helps too, but some people do prefer XC based set ups, even for more 'technical riding'.

You are most definately gonna be a hell of lot faster overall,

But for me faster climbing means nothing as long i get to the top, most important is am i faster and more inspired on my way down, which is become a fairly universal attitude from the people i meet on the trails. Especially the more local steep scary trails.