# 25.4mm vs 31.8mm - Still looking for a definite answer...



## hgg2k (Feb 11, 2011)

Hello to all, 

I have just replaced my trusty but rusty  10 year old steel 25.4mm 
handlebar with a cheap aluminum one of the same diameter bought 
from ebay: (195gr)
Wind Speed Ultralite Flat Handle Bar 25 4 31 8mm | eBay

Despite the fact that its made of 6061 alloy I am not sure If I can
trust it, although it feels stiff enough. It has survived several 2.5 foot 
drops onto concrete. My bike is a hardtail with a 2005 Marzocchi 
Bomber MX Pro 120mm fork.

My riding is basically All Mountain and light DH on mixed very rocky 
and very loose terrain, and I was thinking that it might be a good 
idea to switch to 31.8mm handlebar and stem. The problem is that I 
have not yet found a definite answer to which setup is stronger! 
Both have arguments on which is stronger but its not a clear cut. 
For example there is some info that says 24.5mm is stronger except if 
the 31.8 version is much heavier.
Handlebars standard

So, three questions. Do you think that I need to replace the ebay 
handlebar, and if so shall I go for the 31.8mm setup or file and repaint
my old steel handlebar...?

Thanks!
George.


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## Gman086 (Jul 4, 2004)

As with any component, it's only as good as the manufacturer builds it. There are good and bad for both sizes. I run a 25.4 Easton Havoc on my trail bike that I have no qualms about dropping 5 footers to flat on. It is a DH version of the 25.4 though and never meant to be light. The one you have in your link states "ultralight" with Hong Kong and XC use... I'm sorry but that would be a big FAIL in my book.

If you do buy new, I don't think the diameter dictates the strength but I did notice that the 31.8 on my FR bike is more responsive to rider input which is probably a big reason for the standard change in the past couple of years. Obviously more expensive though as you need to buy a new stem too.

Have FUN!

G MAN


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## hgg2k (Feb 11, 2011)

Hello Gman086,

Ok, one thing is for sure. I am replacing the el-cheapo handlebar...

I guess you are right about the build quality of each manufacturer, but then
I see many named brands that build good quality handlebars, but trying to
save as much material as they can, so in the case of the 31.8mm they will
make a more rigid bar, but more prone to sudden failure.

So, all things being the same, workmanship, material, diameter etc will the
31.8 be better and stronger or not? 

I quote something from another forum:
--------------
Here's an old post courtesy of Eric at Deity that I think answers the question perfectly;
"You know, the biggest misconception between 31.8 and 25.4 Handlebars is that 31.8 is stronger. There is no strength advantage to a 31.8 Handlebar over a 25.4, but what you do gain is stiffness. The oversized 31.8 bore (no matter what material) will be stiffer than a 25.4, but this lends issues also to consider.
For example: hand fatigue, inability to cut bars down as much as a 25.4, and lastly 31.8 bars will weigh a little more due to the extra material necessary for the larger bore size.
--------------

Maybe this question cannot be answered with confidence because of the many 
variables, like the build quality, material, type of construction and so on. 

So I guess the proper question to ask will be, can anybody suggest a race proven
strong and quality handlebar 31.8 or 25.4 at a reasonable price?


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## syl3 (Apr 23, 2008)

25.4 will resist rock impacts better, this is why Santa Cruz did not go to pressfit BB and stayed with the narrow BSA standard, smaller bore means you can pack the same amount of material into a thicker layer which does not crack so fast on hits from sharp edges. This is especially true with carbon but the physics are the same for any other material. The recent obsession with oversize everything comes from frame builders' need for more welding area. If you're talking about tubes that do not need to be welded together, they don't have to be as large as possible at the expense of wall thickness.

I have an old Easton MonkeyLite DH in 25.4 they are bombproof, if you can find one on clearance or on ebay somewhere.


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## hgg2k (Feb 11, 2011)

Hi Syl3, A bit difficult to find the Easton and ship it to Greece as well.
What about the Ritchey Comp Flat Handlebar?
Ritchey Comp Flat Handlebar 31.8mm 620mm Black - Handlebars - ACYCLES

They have a good reputation for quality vs price.


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## syl3 (Apr 23, 2008)

bit narrow for my taste especially for am, i ride 680 xc and 740 am

if you're looking for quality vs price look here especially their house brand rcz:

??????? - ?????????? - ???????? ?????? RCZ Bike Shop


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## hgg2k (Feb 11, 2011)

Thanks, I will have a look.


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## Gman086 (Jul 4, 2004)

Eric's post from Deity is spot on. In fact, if you can find one of their bars in 25.4, buy it!

All things equal though I do like the extra responsiveness of the stiffer 31.8 bars but again, buying a new stem adds a lot to your cost and it's not that noticeable of a difference.

Have FUN!

G MAN


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## hgg2k (Feb 11, 2011)

I am looking for a 5 degree flat bar while they are mostly sell riser bars.
I have their Decoy pedals on my full-sus and they are the best pedals ever!
Excellent quality. Expensive though...


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## Varaxis (Mar 16, 2010)

Trade that lightweight aluminum bar for a can of Boeshield T-9 (and maybe paint), fix up your trusty steel bars, and call it done.


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## hgg2k (Feb 11, 2011)

I might as well do that. The only problem is that the bar has quite some 
rust inside as well. A bit difficult to completely remove the inside rust and 
repaint it. Can the above product be applied underneath a paint coating?
Looks like a temporary rust protection.


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