Ultegra Disc vs Mech how much weight

[jeffy]

Will someone gain more time

* going up hill (from lighter bike)
* going downhill (more confidence/better braking)

1kg = 30 seconds for a 30 minute climb AFAIK (IIRC a Wiggins quote)

[maxxevv]

Thanks for the detailed information!

Side point is that skewers can be used for both, though thru-axles are the correct and better setup.

If that's taken out, its less than 1 pound (410g) in total weight difference.

[mpulsiv]

Again, all of you comparing weight to older caliper BR-RS785, which is ~160 grams heavier in contrast to BR-RS805 flat mount caliper.


Sent from my iPhone using Tapatalk

[jeffy]

so a pair of flat mount are 80g? BR-RS785 are 240g with pads

[mpulsiv]

BR-RS805 (flat mount) ~ 127 grams https://www.bike24.com/1.php?content=8; ... ,4,320,322

BR-RS785 ~ 284 grams https://www.bike24.com/1.php?content=8; ... ,4,320,322


Sent from my iPhone using Tapatalk

[maxxevv]

Its a "piece" versus a " pair" .... look at the description provided by Bike24 again.

[ourmanflint]

Would love to see someone show me weights for frames for both disc and non-disc versions. Lots of people saying it's negligible but I very much doubt that.

[mpulsiv]

Its a "piece" versus a " pair" .... look at the description provided by Bike24 again.

Right, it's ~ 127 grams weight savings per piece x 2 = 254 grams per pair by choosing BR-RS805 over BR-RS785. Am I missing something? Why would anyone invest in older BR-RS785 with ~ 254 grams penalty?

[LeDuke]

One thing that hasn't been addressed yet:

Disc-only rims can be significantly lighter than their rim brake counterparts. See ENVE, etc.

http://enve.com/product-category/ses-disc/

[justaute]

I'm pretty sure he's trying to say it's "one" vs "pair. Thus, the delta is much smaller.

RS805=127g (127x2=254); does not state if it's "filled"; does not state it's a "pair"
RS785=~284g per pair & "filled"

Its a "piece" versus a " pair" .... look at the description provided by Bike24 again.

Right, it's ~ 127 grams weight savings per piece x 2 = 254 grams per pair by choosing BR-RS805 over BR-RS785. Am I missing something? Why would anyone invest in older BR-RS785 with ~ 254 grams penalty?

[CBJ]

One thing that hasn't been addressed yet:

Disc-only rims can be significantly lighter than their rim brake counterparts. See ENVE, etc.

http://enve.com/product-category/ses-disc/

Not correct Madcow has that in his calculation.

[maxxevv]

Yes indeed he has. Its about 30-35g per rim as he listed.

[LeDuke]

My apologies. Read the first page before Madcow responded, typed up my response, hit reply today. Sorry!

Sent from my XT1585 using Tapatalk

[mpulsiv]

I'm pretty sure he's trying to say it's "one" vs "pair. Thus, the delta is much smaller.

RS805=127g (127x2=254); does not state if it's "filled"; does not state it's a "pair"
RS785=~284g per pair & "filled"

Its a "piece" versus a " pair" .... look at the description provided by Bike24 again.

Right, it's ~ 127 grams weight savings per piece x 2 = 254 grams per pair by choosing BR-RS805 over BR-RS785. Am I missing something? Why would anyone invest in older BR-RS785 with ~ 254 grams penalty?

Did you click on "fact sheet"? It says "1 caliper incl. L02A brake pads and front wheel adaptor". No matter how you looking at this, BR-RS805 is new technology, lighter, slimmer and more aero!

http://bike.shimano.com/content/seh-bik ... rior-.html
The new Flat Mount front fork and rear stay fitting also brings aerodynamic advantages by introducing a closer fit between the caliper and the frame, reducing the need for visible mounting bolts.

[justaute]

I sure did. Opinion is just that, opinion. The wordings on bike24 lack precision. Big deal.

No one is arguing that RS805 is not "better". I wished my bike had flat mount and 805, but 785 is fine.

I'm pretty sure he's trying to say it's "one" vs "pair. Thus, the delta is much smaller.

RS805=127g (127x2=254); does not state if it's "filled"; does not state it's a "pair"
RS785=~284g per pair & "filled"

Its a "piece" versus a " pair" .... look at the description provided by Bike24 again.

Right, it's ~ 127 grams weight savings per piece x 2 = 254 grams per pair by choosing BR-RS805 over BR-RS785. Am I missing something? Why would anyone invest in older BR-RS785 with ~ 254 grams penalty?

Did you click on "fact sheet"? It says "1 caliper incl. L02A brake pads and front wheel adaptor". No matter how you looking at this, BR-RS805 is new technology, lighter, slimmer and more aero!

http://bike.shimano.com/content/seh-bik ... rior-.html
The new Flat Mount front fork and rear stay fitting also brings aerodynamic advantages by introducing a closer fit between the caliper and the frame, reducing the need for visible mounting bolts.