Author Topic: Velobuild VB-R-168 Frame  (Read 271333 times)

braincore

Re: Velobuild VB-R-168 Frame
« Reply #180 on: June 24, 2021, 01:05:42 AM »

Please please please dont clamp the seat tube! Lol

How much does the bike weigh with pedals? I habe the dengfu r12 with force etap and farsports 50 classics, i think its 19.2 with pedals. Wheels were 1650g so that attributes a bit of extra weight. that and a 61 cm frame

Is the seat tube that fragile? You're referring to the bike stand clamp, right? Is it a convention not to? It's a rubber grip.

Just weighed it with everything but the bottle cage holders and it's exactly 19.0 lbs. Not as light as I had hoped, but I'm on a full 105 groupset (including the pedals) and the wheels are 1681g.

While I'm not obsessed with reducing weight, out of curiosity, I've been meaning to do an analysis of what upgrades would have the best ROI for weight reduction. Anyone want to fill me in? How much does ultegra or dura-ace / di2 shave off?

Zoc

Re: Velobuild VB-R-168 Frame
« Reply #181 on: June 24, 2021, 03:04:55 AM »
i build frame size 58
sram force etap disc
wheels from velobuild
http://www.velobuild.com/products/road-amp-cyclocross-wheelset-disc-brake-carbon-deep-38mm-width-23-25mm

total 18.5 lbs or 8.4 kg

1Sigma

Re: Velobuild VB-R-168 Frame
« Reply #182 on: June 24, 2021, 08:45:00 AM »
Ultregra and Dura-Ace are squarely in the realm of diminishing gains
Marginal performance improvement and weight savings / dollar

Typical cheaper weight savings areas would be bars and seatpost, but that's not possible with the 168 (I suppose you could cut some excess seatpost for free...)

Tires are a good place to save some weight, especially since they are a consumable part that will need to be replaced anyways.

Depending on your current saddle, that is another cheap place to save weight (especially with Chiner parts)

If you are including pedal weight, and if you don't mind speedplay, there are light Chinese Speedplay compatible titanium pedals out there.

Finally wheels and spokes.  But this is where diminishing returns start kicking in, even with Chiner parts
Better than average - Extra Average

FHS

Re: Velobuild VB-R-168 Frame
« Reply #183 on: June 24, 2021, 08:52:37 PM »
https://ccache.cc/blogs/newsroom/2020-road-gravel-groupset-weight-comparison

Found this online, not sure of its veracity.

I'd switch to a Di2 system for the shifting performance, but not just for weight savings.

Nickk2000

Re: Velobuild VB-R-168 Frame
« Reply #184 on: June 24, 2021, 09:22:06 PM »
i build frame size 58
sram force etap disc
wheels from velobuild
http://www.velobuild.com/products/road-amp-cyclocross-wheelset-disc-brake-carbon-deep-38mm-width-23-25mm

total 18.5 lbs or 8.4 kg

I have an r12 with 50mm 28/28 at about that weight. 19.2 with pedals.

Why are we so heavy? The only upgrades i can think of is a lighter wheelset and get red. Udi2 you save like 50-100 grams. How much difference does a tire set give you? 100 grams?

Nickk2000

Re: Velobuild VB-R-168 Frame
« Reply #185 on: June 24, 2021, 09:27:15 PM »
Is the seat tube that fragile? You're referring to the bike stand clamp, right? Is it a convention not to? It's a rubber grip.

Just weighed it with everything but the bottle cage holders and it's exactly 19.0 lbs. Not as light as I had hoped, but I'm on a full 105 groupset (including the pedals) and the wheels are 1681g.

While I'm not obsessed with reducing weight, out of curiosity, I've been meaning to do an analysis of what upgrades would have the best ROI for weight reduction. Anyone want to fill me in? How much does ultegra or dura-ace / di2 shave off?

I treat my bikes with care, id assume seat tubes arent meant to be clamped, probably not what the manuf made it for. Rubber definitely probably helps but still, ill always use a seatpost.

Udi2 vs force shaves 100 grams tops. Honestly, if you go with 50mm feder series vs 50mm classics, thats 200 grams saved there. Almost half a lb. a lighter tyre set would save 50-100 probably. Speedplay lookalikes save 100-150 i think.

Problem is you cant get a lightweight AND aero bike, aero bikes from china are always over 1 kg.
Thats all the weight savings i can think of, im assuming you use a cf saddle already.
So if you go with the same depth and swap everything, youre looking at maybe 1-1.5 lb MAX after swapping anything and im so fat that that weight doesnt matter, i just hate seeing my bike on the scale.

Nickk2000

Re: Velobuild VB-R-168 Frame
« Reply #186 on: June 24, 2021, 09:28:52 PM »
Ultregra and Dura-Ace are squarely in the realm of diminishing gains
Marginal performance improvement and weight savings / dollar

Typical cheaper weight savings areas would be bars and seatpost, but that's not possible with the 168 (I suppose you could cut some excess seatpost for free...)

Tires are a good place to save some weight, especially since they are a consumable part that will need to be replaced anyways.

Depending on your current saddle, that is another cheap place to save weight (especially with Chiner parts)

If you are including pedal weight, and if you don't mind speedplay, there are light Chinese Speedplay compatible titanium pedals out there.

Finally wheels and spokes.  But this is where diminishing returns start kicking in, even with Chiner parts

Farsports has a line where they use carbon fiber spokes, i forget the depth but its 1300-1400 for the wheelset so id assume its 45-55.
Lun wheels might actually be a place to look at too, but those tend to be more expensive than our likings

braincore

Re: Velobuild VB-R-168 Frame
« Reply #187 on: June 25, 2021, 03:25:19 AM »
As I was trying to investigate my bearings issue, I discovered that my preload bolt hasn't been correctly clamping / compressing the headset!



If I keep tightening the preload bolt, it pulls completely out of the fork with the expansion contraption. The expansion contraption doesn't seem to be expanding properly to secure itself. Because everything is a pretty snug fit, it didn't come apart on me while riding it.

Any ideas?

kjfekfrekgnr

Re: Velobuild VB-R-168 Frame
« Reply #188 on: June 25, 2021, 08:30:54 AM »
Have you tried it without the top triangle cover? The bolt might not be going down enough to push out the expanding sleeve.

I've just received my 168 yesterday so the build starts this weekend. I noticed I've got a different handle bar to you. Mine seems to be this one (http://www.velobuild.com/products/carbon-fiber-road-bike-integrated-handlebar-with-spacers-for-hidden-cables-routing), notice there's the two bolts on the side for tightening, rather than that bolt insert. It only came with the spacers and expander too.

FHS

Re: Velobuild VB-R-168 Frame
« Reply #189 on: June 25, 2021, 08:40:20 AM »
As I was trying to investigate my bearings issue, I discovered that my preload bolt hasn't been correctly clamping / compressing the headset!



If I keep tightening the preload bolt, it pulls completely out of the fork with the expansion contraption. The expansion contraption doesn't seem to be expanding properly to secure itself. Because everything is a pretty snug fit, it didn't come apart on me while riding it.

Any ideas?

I never could get that compression plug to work. I swapped it out for this one. No problem with slipping since.


https://www.ebay.com/itm/274059545505

Snacks

Re: Velobuild VB-R-168 Frame
« Reply #190 on: June 25, 2021, 10:05:04 AM »
I treat my bikes with care, id assume seat tubes arent meant to be clamped, probably not what the manuf made it for. Rubber definitely probably helps but still, ill always use a seatpost.

If you really want to be a stickler about it then clamping at the seatpost isnt isn't good idea either.  Both the seatpost and the seat tube have a layup that promotes stiffness vertically. Clamping either of them can cause damage while working on the bike. I would have to assume if anything, clamping at the seat tube would be better if theseat post was inside to give it extra rigidity where you clamp.

On a carbon fiber frame you either want a stand with hanging hooks or the best option is to use one with where you remove the front wheel and the frame rests on the bottom bracket like this one from feedback Sports


Nickk2000

Re: Velobuild VB-R-168 Frame
« Reply #191 on: June 25, 2021, 12:28:06 PM »
If you really want to be a stickler about it then clamping at the seatpost isnt isn't good idea either.  Both the seatpost and the seat tube have a layup that promotes stiffness vertically. Clamping either of them can cause damage while working on the bike. I would have to assume if anything, clamping at the seat tube would be better if theseat post was inside to give it extra rigidity where you clamp.

On a carbon fiber frame you either want a stand with hanging hooks or the best option is to use one with where you remove the front wheel and the frame rests on the bottom bracket like this one from feedback Sports

Youre probably right, but it is easier to replace a seatpost than it is to replace a seat tube. Lol

Nickk2000

Re: Velobuild VB-R-168 Frame
« Reply #192 on: June 25, 2021, 12:29:00 PM »
i build frame size 58
sram force etap disc
wheels from velobuild
http://www.velobuild.com/products/road-amp-cyclocross-wheelset-disc-brake-carbon-deep-38mm-width-23-25mm

total 18.5 lbs or 8.4 kg

Have you experienced the sram mating call with the rotors squealing just riding around? Im currently battling that

Edit: rotor was a little bent from a crash and i realigned the brakes, looks good but ill take it out for a spin this evening and see if it wants to mate.
« Last Edit: June 25, 2021, 03:58:04 PM by Nickk2000 »

braincore

Re: Velobuild VB-R-168 Frame
« Reply #193 on: June 25, 2021, 02:00:26 PM »
I never could get that compression plug to work. I swapped it out for this one. No problem with slipping since.

https://www.ebay.com/itm/274059545505

It was my error. I didn't realize that the female thread could be separately tightened with an allen key that forces the expansion. I had expected that tightening the male bolt would both expand the unit radially and compress the headset vertically, which seems unreasonable in retrospect.

UPDATE: Sure enough, I went for a ride and the loose-bearing issue has been resolved.
« Last Edit: June 25, 2021, 06:29:31 PM by braincore »

kjfekfrekgnr

Re: Velobuild VB-R-168 Frame
« Reply #194 on: June 27, 2021, 06:24:41 AM »
So I've started the build this weekend and have a couple of questions. How did you route and secure the gear cable to the FD? The bend from the down tube over the BB to the cable exit is quite tight and there doesn't seem to be anywhere to clip/secure the outer cable to the exit grommet.

Also I have a slightly different handlebar to you guys. Mine has two stem bolts that at the back, however, I cant seem to tighten them together (similar to this handlebar setup at 18:27 https://www.youtube.com/watch?v=IQWYPxGicjU][url] https://www.youtube.com/watch?v=IQWYPxGicjU [/url]. When positioned on the stem the two parts don't engage fully so I can't tighten against the stem.
« Last Edit: June 27, 2021, 06:30:25 AM by kjfekfrekgnr »