Factor Ostro

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Mr.Gib
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by Mr.Gib

Yes, aprox 450g for the new fork was what I have seen. Crazy to think that my cut fork on my O2 VAM was 259g :shock:
870 grams for a 49 has me estimating that a 56 will probably be in the 950 - 975 range. Not particularely light. The days of being able to buy a rideable 1000 gram frame and fork are getting further in the rear view mirror. I guess this is what we call progress.
wheelsONfire wrote: When we ride disc brakes the whole deal of braking is just like a leaving a fart. It happens and then it's over. Nothing planned and nothing to get nervous for.

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ichobi
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by ichobi

It’s hard to make fancy paint that doesnt weight a lot. 52 flickr is 780g but thats almost cheating with zero paint layer. Go up sizes and you are nearing 900 for sure and as discussed forks are heavy, but also with the new fork you no longer need expander plug. I weighted the plug at around 30-40g if memory serves.

Guess thats why the likes of Woods and Froome ride with Darimo seatpost.

mrlobber
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by mrlobber

It puzzles me a bit, what's there so heavy for the fork. The O2 VAM revised internal-routing fork (with the star-shaped fork internals where the asymmetric top cap bolt screws in) was 360g uncut, 330g cut for a size 56 frame.
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Mr.Gib
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by Mr.Gib

ichobi wrote:
Thu Sep 29, 2022 5:28 am
It’s hard to make fancy paint that doesnt weight a lot. 52 flickr is 780g but thats almost cheating with zero paint layer. Go up sizes and you are nearing 900 for sure and as discussed forks are heavy, but also with the new fork you no longer need expander plug. I weighted the plug at around 30-40g if memory serves.

Guess thats why the likes of Woods and Froome ride with Darimo seatpost.
I didn't want flicker and figured that black/chrome would be similarely light.
mrlobber wrote:
Thu Sep 29, 2022 9:44 am
It puzzles me a bit, what's there so heavy for the fork. The O2 VAM revised internal-routing fork (with the star-shaped fork internals where the asymmetric top cap bolt screws in) was 360g uncut, 330g cut for a size 56 frame.
Sorry are you asking about the difference between new and old O2 forks or comparing to the Ostro fork? At least with the Ostro it's just a chunkier item, pretty damn wide and deep. More material so more weight. Re the O2 fork, The weight gain on the new O2 fork I assume is due to additional hardware and material to accomodate the full integration. It wouldn't surprise me to learn that additioanl material was added elsewhere to make things generally stiffer. My understanding is there were a lot of complaints from the sponsored riders about the O2 VAM stiffness. I believe most or all of the later O2 VAM's that you saw being raced at the pro level were regular O2's painted to look like VAM's.

Interestingly, though I found the O2 frame too flexible for me (and the O2 VAM way too flexible), I found the forks on each to be more than adequately stiff despite their slender profile. Perhaps a bit too much flex in the steerer but the legs felt solid.
wheelsONfire wrote: When we ride disc brakes the whole deal of braking is just like a leaving a fart. It happens and then it's over. Nothing planned and nothing to get nervous for.

mrlobber
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by mrlobber

Mr.Gib wrote:
Thu Sep 29, 2022 4:10 pm
Sorry are you asking about the difference between new and old O2 forks or comparing to the Ostro fork? At least with the Ostro it's just a chunkier item, pretty damn wide and deep. More material so more weight. Re the O2 fork, The weight gain on the new O2 fork I assume is due to additional hardware and material to accomodate the full integration. It wouldn't surprise me to learn that additioanl material was added elsewhere to make things generally stiffer. My understanding is there were a lot of complaints from the sponsored riders about the O2 VAM stiffness. I believe most or all of the later O2 VAM's that you saw being raced at the pro level were regular O2's painted to look like VAM's.

Interestingly, though I found the O2 frame too flexible for me (and the O2 VAM way too flexible), I found the forks on each to be more than adequately stiff despite their slender profile. Perhaps a bit too much flex in the steerer but the legs felt solid.
I was specifically referring to the weight difference between O2 VAM and Ostro VAM fork. I believe the steerer should be the same, just the fork blades are chunkier - whether there's so much extra material... most likely, but still a bit surprising overall.

Regarding the frame, I ride O2 VAM Disc, and cannot really share your sentiment of noticeable flex even though I'm pretty close to your weight too, but I visit proper mountains maybe once per year only, and certainly aren't qualified descender enough to push the bike to its limits the way you used to in your Factor reviews.

Edit: found that I actually already commented in your O2 thread :D
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wheelsONfire
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by wheelsONfire

Hm, it seems Ostro isn't much lighter than Dogma F?
I wonder if it's possible to get same deal for a Dogma F as a new Ostro frameset!?
If i could, i would easily go for Dogma.
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Mr.Gib
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by Mr.Gib

mrlobber wrote:
Thu Sep 29, 2022 5:31 pm
I was specifically referring to the weight difference between O2 VAM and Ostro VAM fork. I believe the steerer should be the same, just the fork blades are chunkier - whether there's so much extra material... most likely, but still a bit surprising overall.
I am similarely perplexed. 100 grams difference for a fork at this level is huge. Perhaps a lot of it has to do with the shoulders of the Ostro fork. They are pretty beefy.

As for the stiffness issues with the O2, the problem was only in a very specific situation. The rest was fine. So it's horses for courses. Can't wait to get on the Ostro. After a thorough shakedown I'll give my impressions here and compare it to the O2 and O2 VAM.
wheelsONfire wrote: When we ride disc brakes the whole deal of braking is just like a leaving a fart. It happens and then it's over. Nothing planned and nothing to get nervous for.

ichobi
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by ichobi

Ostro fork is pretty much a tt bike fork - shape wise. They are really chunky. But agreed could drop a few dozen grams there. Anyhow i think this still makes a decently weighted aero bike. The black inc cockpit does help since it’s one of the lightest integrated bar stem on the market. Pretty comfortable too.


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BigBoyND
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by BigBoyND

wheelsONfire wrote:
Thu Sep 29, 2022 11:23 pm
Hm, it seems Ostro isn't much lighter than Dogma F?
I wonder if it's possible to get same deal for a Dogma F as a new Ostro frameset!?
If i could, i would easily go for Dogma.
Seriously. Some of the weights mentioned seem equal or heavier to the Venge
2019 Spec Venge 58cm 6.85kg
- R9270/R8170, Quarq, i9.65
2021 Canyon Speedmax Disc CF8 XL heavy
- R8000, P2M, SwissSide 80 + Citec Disc

Retired:
2020 Pina Prince 59.5cm 7.4kg
2017 Cervélo P5 58cm heavy

Scott2017
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by Scott2017

Weight of the fork could also be from the "Reversing Flow Energising Channel" thingy above the tire, some extra shaping there for that which might add a fair bit more heft compared to a usual aero fork. They seem to have dropped mention of it on their website, perhaps they plan to get rid of it for their next model. Still would like to see some wind tunnel data on this bike that's not from Factor.

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cyclespeed
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by cyclespeed

Regarding the fork, what you are all missing is that the new UNCUT Ostro fork will be very heavy because you have the thread insert moulded in all the way up the steerer.

It's like having a massive expansion plug in it.

But when you cut the steerer, you lose most of this weight, so the fork returns to quite a light level. My Ostro LOST weight when I went to the new fork, because I have no spacers (slammed stem) and could therefore remove most of the heavy steerer, and of course there is no expansion plug to insert.

(To explain another way, say you cut off 100mm of steerer. On a normal fork that may weigh 35g, but on this new Ostro fork it's more like 80g. (Guesstimating here))

ichobi
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by ichobi

Let's look at the real weight here. I actually documented the swapping from the OG forks (1st iteration - expander plug) to the 3rd forks iteration (screwed in - , no plug)

1. Let's start with the V1 OG Forks, cut to my fit - 386g
OG - Cut.jpeg
2. Here's how much the V1 expander plug weight - 39g
Old - Expander plug.jpeg
So the OG versions Forks + Plug all in all is 386+39 = 425g

------------------------

3. Now the new uncut V3 forks (screwed in) - 467g chunky boy
New - Uncut.jpeg
4. But when cut to my fit, the new fork is only 419g
New - Cut.jpeg
Therefore, I have removed 48g from the steerer cutting alone.

And my new forks are a wee bit lighter than the OG forks - 6g in total. A wash all things considerd but with less part to worry about.

-------------
The fork remains quite heavy if you compared to non-aero bike forks. SL7 forks is aroud 380g but they are a lot more svelt than the Ostro's.

Howevver, i'd still argue if you compared to other aero road bike, Ostro VAM is still one of the lightest to build up and tune. With similar paint, it's pretty much weights the same - frames and forks as the SL7 when hardwares and cockpits are included. I'd venture to say will definitely be lighter than the Dogma F, and A LOT cheaper given the fact that you have to buy the MOST Talon one piece bar stem separately, as well as the BB - all of which supplied with the Ostro frameset.
Attachments
New - cut streerer.jpeg

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cyclespeed
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by cyclespeed

Yes, and it depends how slammed your stem is. With no spacers you get to cut off a lot of steerer which removes all of the 'excess' weight that people are talking about here.

But if you have a very 'sit up' position and you cut off less then maybe you end up heavier than before, because you have a load of insert that is doing nothing.

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wheelsONfire
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by wheelsONfire

BigBoyND wrote:
Fri Sep 30, 2022 4:12 am
wheelsONfire wrote:
Thu Sep 29, 2022 11:23 pm
Hm, it seems Ostro isn't much lighter than Dogma F?
I wonder if it's possible to get same deal for a Dogma F as a new Ostro frameset!?
If i could, i would easily go for Dogma.
Seriously. Some of the weights mentioned seem equal or heavier to the Venge
I don't think so, honestly! New Dogma F isn't that heavy according to what i have read. A 55 size is equal to a 56 size Ostro. The 56 size Dogma F is larger.
The fork seems lighter!
https://ccache.cc/blogs/newsroom/pinare ... mpressions
Bikes:

Ax Lightness Vial EVO Race (2018.12.21)
viewtopic.php?f=10&t=156137
Paduano Racing Fidia (kind of shelved)
Open *UP* (2016.04.14)


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BigBoyND
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by BigBoyND

ichobi wrote:
Fri Sep 30, 2022 10:23 am
heavy if you compared to non-aero bike forks. SL7 forks is aroud 380g but they are a lot more svelt than the Ostro's.

Howevver, i'd still argue if you compared to other aero road bike, Ostro VAM is still one of the lightest to build up and tune. With similar paint, it's pretty much weights the same - frames and forks as the SL7 when hardwares and cockpits are included. I'd venture to say will definitely be lighter than the Dogma F, and A LOT cheaper given the fact that you have to buy the MOST Talon one piece bar stem separately, as well as the BB - all of which supplied with the Ostro frameset.
That SL7 weight doesnt seen right. My Venge fork cut to a 58cm head tube is 347g including the crown race, and thats a deep aero fork, not all-rounder.

What do you mean by the Ostro being easy to "tune"? Both Venge and SL7 allow the use of ultralight cockpits (RSL VR-C, Alpinist, Nexum, etc.), so that isn’t a point for the Ostro. All other components can be identical.

With the same paint on the Ostro and Dogma (bare on both or thick on both), I'd guess the Dogma could come out lighter thanks to Ti hardware
2019 Spec Venge 58cm 6.85kg
- R9270/R8170, Quarq, i9.65
2021 Canyon Speedmax Disc CF8 XL heavy
- R8000, P2M, SwissSide 80 + Citec Disc

Retired:
2020 Pina Prince 59.5cm 7.4kg
2017 Cervélo P5 58cm heavy

by Weenie


Visit starbike.com Online Retailer for HighEnd cycling components
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