Velocite filament wound rims

Everything about building wheels, glueing tubs, etc.
Nefarious86
Moderator
Posts: 2181
Joined: Sun May 25, 2014 4:57 am
Contact:

by Nefarious86

mpulsiv wrote:
spartan wrote:
Sat Jan 20, 2018 6:29 pm
i see the probikekit.com is selling venn wheelsets. nice. finally accessible to a worldwide audience. pricing is so so.
Nice!
$745 and free shipping is tempting www.probikekit.com/bicycle-wheels/venn- ... 87629.html
Damn that's cheap

Sent from my SM-N950F using Tapatalk

Using Tapatalk

spartan
Posts: 1106
Joined: Fri Sep 03, 2004 2:52 am

by spartan

it seems probikekit they lowered their prices. it was $500 more expensive since i posted.
i like the disc 50mm tubeless model. too bad it is still 5 bolt instead of centermount
Current Rides:

2017 Giant TCR Advanced SL 0 DI2 9150

by Weenie


yltman
Posts: 7
Joined: Tue Nov 21, 2017 12:50 pm

by yltman

vmajor, I've read reviews on the 507 wheels, you posted before
viewtopic.php?p=1287164#p1287164
and
viewtopic.php?p=1287853#p1287853

could you please tell us more, why do they feel stable, than U-shape wheels in crosswinds? have you done something special to achieve that?

coolman2001
Posts: 16
Joined: Sat Mar 08, 2014 2:38 am

by coolman2001

Has there been any aerodynamic test done on the Venn 507? Quite interested in those.

User avatar
vmajor
Shop Owner / Manufacturer
Posts: 423
Joined: Wed Oct 15, 2008 4:09 am
Location: Beringen, Belgium
Contact:

by vmajor

yltman wrote:
Tue Feb 06, 2018 9:49 am
vmajor, I've read reviews on the 507 wheels, you posted before
viewtopic.php?p=1287164#p1287164
and
viewtopic.php?p=1287853#p1287853

could you please tell us more, why do they feel stable, than U-shape wheels in crosswinds? have you done something special to achieve that?
Well, it is complicated :) But it has to do with the pitching moment and the center of torque as we have a rather odd looking wing (pitching moment applies to airplane wings). In essence I designed the shape so that the center of torque never moves far from the axis of rotation. Thus all that you will experience in cross winds is lateral force, not turning force on your handlebars.

"U-shaped" rims - actually truncated extended laminar flow airfoils can work too, but because their virtual airfoil length is rather large the center of torque can easily end up behind the rotational axis of the wheel, causing significant torque on the handlebars in some situations.

User avatar
vmajor
Shop Owner / Manufacturer
Posts: 423
Joined: Wed Oct 15, 2008 4:09 am
Location: Beringen, Belgium
Contact:

by vmajor

coolman2001 wrote:
Wed Feb 07, 2018 1:36 am
Has there been any aerodynamic test done on the Venn 507? Quite interested in those.
No, but there will be soon. However, they will perform within the margin of error of any other 50mm rim. What they do a lot better than many rims in the market is handle very well in crosswinds. This is a real life benefit and allows you to stay in the aero position longer and with more confidence. Most of the drag comes from you after all, so if you stay tucked in, rather than upright and scared for your life, you will go faster :)

V.

User avatar
MayhemSWE
Posts: 118
Joined: Thu Mar 12, 2015 12:44 pm
Location: Stockholm, Sweden

by MayhemSWE

Do you use any nipple washers or such when building up Rev 35 wheels in the factory? Also I was told by the sales lady that you use 16 mm nipples which seems a bit excessive, is there any particular reason for this? Was thinking of using Wheel Fanatyk splined alloy nipples for my build but those only come in 12 mm length. Seems to be more than enough clearance between the spoke wrench and rim in my quick tests, unless washers are recommended that is.

Finally got my rims a few weeks ago. Took quite a while as I elected to wait for availability of black decals, but I'm happy that I did because they look awesome! Still plenty of time to build either way as these wheels won't be used for another two months or so. Aside from the Wheel Fanatyk nipples I will be using DT Swiss 350 hubs and Aerolite/Aero Comp driveside spokes, should give lots of bang for a reasonable buck!

yltman
Posts: 7
Joined: Tue Nov 21, 2017 12:50 pm

by yltman

vmajor wrote:
Wed Feb 07, 2018 5:45 pm
Well, it is complicated :) But it has to do with the pitching moment and the center of torque as we have a rather odd looking wing (pitching moment applies to airplane wings). In essence I designed the shape so that the center of torque never moves far from the axis of rotation. Thus all that you will experience in cross winds is lateral force, not turning force on your handlebars.

"U-shaped" rims - actually truncated extended laminar flow airfoils can work too, but because their virtual airfoil length is rather large the center of torque can easily end up behind the rotational axis of the wheel, causing significant torque on the handlebars in some situations.
thanks for the answers, but now I have more questions :D

I am a light rider (62-65kg), so what do you think about using 35/44mm rim for the front wheel? do they as aero as 50mm rim? do they work in crosswinds? or 50/50 will be better than 35/50?

and second question, you said that it is optimized for 23/25mm tires, but internal rim width is 21mm, so the question is it safe to ride on tires which actually will be 23mm wide (like veloflex), for example on fast corner or when it gets flat on descend, is there any chance that the rim will go in other direction than tire or it will stay secure on the rim?

User avatar
vmajor
Shop Owner / Manufacturer
Posts: 423
Joined: Wed Oct 15, 2008 4:09 am
Location: Beringen, Belgium
Contact:

by vmajor

The 507 actually handles better in crosswinds than the Alter 44. 44 is however lighter.

Our test riders ranged in weight from approx 60 to a bit over 80kg. All of them reported no issues with handling, but, it depends on your specific conditions.

I am not familiar with Veloflex tires, but I do not believe they are radially reinforced. There is only one afaik, the Maxxis Radiale. Only radially reinforced tires would keep their shape when inflated. Bicycle tires are more like stiff balloons so none of them will inflate to the nominal tire width on every rim. This also means that there is no issue with safety, but tires under 23mm wide may end up being overly square when inflated.

User avatar
mpulsiv
Posts: 1021
Joined: Mon Mar 24, 2014 9:17 pm

by mpulsiv

yltman wrote:
Thu Feb 08, 2018 7:57 am
vmajor wrote:
Wed Feb 07, 2018 5:45 pm
Well, it is complicated :) But it has to do with the pitching moment and the center of torque as we have a rather odd looking wing (pitching moment applies to airplane wings). In essence I designed the shape so that the center of torque never moves far from the axis of rotation. Thus all that you will experience in cross winds is lateral force, not turning force on your handlebars.

"U-shaped" rims - actually truncated extended laminar flow airfoils can work too, but because their virtual airfoil length is rather large the center of torque can easily end up behind the rotational axis of the wheel, causing significant torque on the handlebars in some situations.
thanks for the answers, but now I have more questions :D

I am a light rider (62-65kg), so what do you think about using 35/44mm rim for the front wheel? do they as aero as 50mm rim? do they work in crosswinds? or 50/50 will be better than 35/50?

and second question, you said that it is optimized for 23/25mm tires, but internal rim width is 21mm, so the question is it safe to ride on tires which actually will be 23mm wide (like veloflex), for example on fast corner or when it gets flat on descend, is there any chance that the rim will go in other direction than tire or it will stay secure on the rim?

In grand scheme of things, ~15mm extra depth (e.g. going from 35mm to 55mm wheel) will save you up to 7 seconds in 40k. That's on a good day. Realistically, expect 4 seconds advantage in 40k.
Veloflex (runs narrow) is a cotton tire, sidewalls are not reinforced. Mounting this tire (E.T.R.T.O. 17mm) on 21mm inner rim is a risky business. The tire can roll off. If I remember correctly, some riders reported no issues up to 19mm inner rim.

Image
Racing is a three-dimensional high-speed chess game, involving hundreds of pieces on the board.

:arrow: CBA = Chronic Bike Addiction
:arrow: OCD = Obsessive Cycling Disorder

rangi69
Posts: 7
Joined: Mon Feb 12, 2018 2:09 am

by rangi69

Just ordered from PBK - Looking forward to it. Will be my first set of Carbon wheels - coming from quattro LG's and fulcrum 3;s so hoping for some free speed! :thumbup:

rangi69
Posts: 7
Joined: Mon Feb 12, 2018 2:09 am

by rangi69

Is there a recommended tyre for the 507 Clincher version? I'm debating whether to go tubeless for the first time - Ive alway had 4000sII and have a spare pair of 25mm tyres on hand.

User avatar
vmajor
Shop Owner / Manufacturer
Posts: 423
Joined: Wed Oct 15, 2008 4:09 am
Location: Beringen, Belgium
Contact:

by vmajor

We have good long term data with Panaracer - it completed several ultra distance races in Europe (Hardcro, Transcontinental) and with Maxxis even though I know it is not that common in Europe. However I designed the shape of the 507 tire interface to work with any tubeless ready or tubeless tire. It does lock the bead in tight though once inflated so to remove the tire you will need to roll the bead out of the internal channel. The upside is that the tire should stay on even in case of total air pressure loss.

V.

Hexsense
Posts: 368
Joined: Wed Dec 30, 2015 12:41 am

by Hexsense

vmajor wrote:
Wed Aug 30, 2017 2:46 am
In not immediately useful news, we have a 76mm rim profile design ready. We developed the profile by using an artificial intelligence optimisation loop, within constraints. When we let it loose the optimal width of the rim with a 25mm tire and 76mm depth was 45mm which was not going to work... I hope to have the 76mm rim ready this year sometime.
V.
Well, this take longer than i hoped for. Any update yet?
The 50.7 is perfect height for using 60mm valve without extender (Michelin make 60mm valve Latex tube). I was hoping i would see wider variety of rim height in the wide rim collection.
50.7mm up front and 60-80mm in the rear would make a sweet combo (at least for me, 140-150lbs rider during the season)

by Weenie


rangi69
Posts: 7
Joined: Mon Feb 12, 2018 2:09 am

by rangi69

Can someone please confirm - with the venn wheelset from PBK - what further is needed to go tubeless other than sealant (i see they include the valves). Also with an internal rim width at 21mm - does this mean that it is not best practise to use tubes/standard non tubeless 25mm tyres (ie dangerous in a puncture situation) or am I being paranoid???

Post Reply
  • Similar Topics
    Replies
    Views
    Last post