HOT: Active* forum members generally gain 5% discount at starbike.com store!
Weight Weenies
* FAQ    * Search    * Trending Topics
* Login   * Register
HOME Listings Articles FAQ Contact About




Post new topic Reply to topic  [ 39 posts ] 
Go to page Previous  1, 2, 3  Next
Author Message
PostPosted: Thu Nov 29, 2012 10:00 am 
Offline
in the industry

Joined: Sat May 12, 2012 7:25 pm
Posts: 1222
Location: Glermsford, Suffolk U.K
artray the ammount of wheel flex you get depends on how you ride. the OP may have a different riding styole to you or just set his pads closer to the rim. After Ithink this is how people are assessing wheel flex. How the wheel is built should not make a difference to the flex either. Spoke tension does not affect wheel stiffness after all unless flex is severe enough to cause NDS spokes to go slack then stiffness drops. so long as NDS tension is sufficent to prevent that from happening given the riders riding style and power output then this issue will not manifest itself.

Hub choice also make a difference. The OP has not stated what hubs where used nor did you artray. Hubs with shorter flange spacings and short DS spacing tend to built into less stiff wheels.

In reality everyone is different but if the OP is expericencing wheel flex then a stiffer build is needed. That normally means more weight.

_________________
www.thecycleclinic.co.uk


Top
 Profile  
 
PostPosted: Thu Nov 29, 2012 10:07 am 
Offline
in the industry

Joined: Sat May 12, 2012 7:25 pm
Posts: 1222
Location: Glermsford, Suffolk U.K
artray and the OP have not said what hubs are being used. this makes a big difference to wheel stiffness.

Also brake rub seems to be the way you are all assessing wheel flex and how you set your pads up will determine what you experience. Not a goiod way of determining wheel flex. Also rim depth will affect how much rim movement there is.

Artray how the wheel is built should not affect wheel stiffnes as tension does not affect lateral wheel stiffness. So long as the NDS tension is sufficent to prevent these spokes going slack when the wwheel flex then how it is built does not matter much. 2x lacing though is marginally laterally stiffer than 3x but not by much.

_________________
www.thecycleclinic.co.uk


Top
 Profile  
 
Posted: Thu Nov 29, 2012 10:07 am 


Top
  
 
PostPosted: Thu Nov 29, 2012 10:41 am 
Offline

Joined: Fri Oct 07, 2011 2:08 pm
Posts: 1365
Sorry :oops: . Im using American classic hubs on my Stans . On my new wheels which are not built yet I have got the Dati super light hubs.
Can I ask about the effects of spokes .I am considering some Pillar ti spokes ? whats your opinion out there.


Top
 Profile  
 
PostPosted: Thu Nov 29, 2012 11:47 am 
Offline
in the industry

Joined: Sat May 12, 2012 7:25 pm
Posts: 1222
Location: Glermsford, Suffolk U.K
Titanium has 60% the stiffness of steel. So Ti spoke may be lighter but when used with a light flexy rim like the XR-200 will be more more flex than you experience with your Stans 340 American Classic build. The dati hub you plan to use has a short flange speration of 50mm DS flange spacing is 17.5mm and NDS spacing is 32.5mm. the short NDS drive spacing is there to keep NDs tension high but lateral wheel stiffness is sacrificed.

So in summary, Ti flexy spokes, and light flexible rim and ahub with narrow spacing make for a flexy wheel.

If you are going to use Ti spokes use a hub with good rear flange sperations like Alchemy (what ever Lord of the rings name it has), Novatec F482 SB or F482 SB-SL, CK R45, Dura ace 7800/7900 e.t.c. A stiffer rim will help too.

Even with stainless spokes I would pick a different hub like one of the above with the Xr-200. The american classic hubs you have used have similar rear flange seperation to the Dati rear hub but the flanges are larger giving a higher NDS bracing angle helping lateral stiffness abit. Also that build had stiffer SS spokes.

Alot of the hubs I use have DS flange spacing of 17-20mm and an NDS spacing of around 37mm. Novatec hubs are DS= 18mm and NDS 37mm. flange diameter iare small than the AC hubs though at DS 49 NDS 41mm. Still those hubs with 28 2x Sapim Laser spokes on a XR-200 rim give acceptable lateral stiffnes.




.

_________________
www.thecycleclinic.co.uk


Top
 Profile  
 
PostPosted: Thu Nov 29, 2012 12:05 pm 
Offline

Joined: Mon Dec 14, 2009 6:26 pm
Posts: 827
Not commenting on the stiffness issue, Ti spokes are more likely to break. If you're miles from home and out in the middle of nowhere, and get a puncture, no probs but a broken spoke and you're fuc#ed.

I had Ti spokes on my AX/tune (830g i think) wheel build and this happened to me twice in quite a short period of time. I replaced with steel. No problems since.

P.S. From the beginning I had steel spokes on rear drive side.


Top
 Profile  
 
PostPosted: Thu Nov 29, 2012 12:32 pm 
Offline
in the industry

Joined: Sat May 12, 2012 7:25 pm
Posts: 1222
Location: Glermsford, Suffolk U.K
The failure may have down to wheel flex. If the flex is sufficent to completely unload the NDs spokes then they will fatigue much quicker.

_________________
www.thecycleclinic.co.uk


Top
 Profile  
 
PostPosted: Thu Nov 29, 2012 2:19 pm 
Offline

Joined: Fri Oct 07, 2011 2:08 pm
Posts: 1365
Thanks for your advice ,it's very welcome :thumbup: It seems that the ti spokes are an issue . I did read up on them and they have had mixed views but Konky makes a good point having used ti spokes then bm0p700f
makes another good point about wheel flex,it's all to much so ive decided to get new a car :lol: .
thanks again :thumbup:


Top
 Profile  
 
PostPosted: Thu Nov 29, 2012 2:32 pm 
Offline
User avatar

Joined: Sun Dec 28, 2008 10:15 pm
Posts: 1203
Location: Hungary
CharlesM says the same as what I read from Roues Artisanales. The more rubbing you get the stiffer the wheel.


Top
 Profile  
 
PostPosted: Thu Nov 29, 2012 3:13 pm 
Offline
in the industry

Joined: Sat May 12, 2012 7:25 pm
Posts: 1222
Location: Glermsford, Suffolk U.K
The roules artile is a good one. Quote from part 3.

"The parameters playing a role here are not well known but when digging deep inside the stiffness/deflections at 180° sheet, there are at least two important parameters:
- the rim depth: the shallower it is, the smaller are the deflections between the brake pads, but the lower is the lateral stiffness of the wheel
- the spoking: the higher is the spoke count, the lower are the deflections between the brake pads, and the higher is the wheel stiffness.

Thus, a box section rim with a high spoke count can have two times less deflections between the brake pads, than a wheel with the same construction but a deep rim and a low spoke count!"

So this is why brake pad rubbing is not a good way of determining lateral wheel stiffness. However good wheels can be built with Ti spokes but the shorter the spokes the better so that deep V setion rims, the deeper the better. Aslo deep rim tend to be stiffer so I think they will be best used with carbon rims but I am sure there are some alloy rim combinations where they can be made to work well to.

_________________
www.thecycleclinic.co.uk


Top
 Profile  
 
PostPosted: Thu Nov 29, 2012 5:25 pm 
Offline
User avatar

Joined: Tue Jan 23, 2007 11:22 am
Posts: 3657
Location: Leg hurty
Don't go Ti spokes......period. They don't work. Every material has an ideal use in cycle engineering, but the combination of spoke and Ti is not a marriage made in heaven. :thumbup:

_________________
Pedalling Law Student.


Top
 Profile  
 
PostPosted: Thu Nov 29, 2012 6:13 pm 
Offline

Joined: Fri Oct 07, 2011 2:08 pm
Posts: 1365
I think I will go with sapim . They would get my wheels around the 1200 grm mark .
:beerchug:


Top
 Profile  
 
PostPosted: Thu Nov 29, 2012 6:43 pm 
Offline
in the industry
User avatar

Joined: Sun Jul 29, 2012 2:59 pm
Posts: 612
Location: Ruidoso, NM
konky wrote:
I had Ti spokes on my AX/tune (830g i think) wheel build and this happened to me twice in quite a short period of time.


Which Ti spokes?

_________________
formerly rruff...


Top
 Profile  
 
PostPosted: Thu Nov 29, 2012 6:45 pm 
Offline
in the industry
User avatar

Joined: Sun Jul 29, 2012 2:59 pm
Posts: 612
Location: Ruidoso, NM
legs 11 wrote:
Don't go Ti spokes......period. They don't work. Every material has an ideal use in cycle engineering, but the combination of spoke and Ti is not a marriage made in heaven. :thumbup:


If they hold up, the NDS rear is an excellent place for them... if the hub has wide NDS spacing.

_________________
formerly rruff...


Top
 Profile  
 
PostPosted: Thu Nov 29, 2012 6:56 pm 
Offline

Joined: Thu Aug 30, 2012 8:42 pm
Posts: 94
I dunno, my last few wheels were a pair of cheep OEM wheels which were uncomfortably stiff, then some low end shimano factory wheels (r550) which were more comfortable but don't feel (to me) to be flexing. Treated myself to these new wheel's and they don't feel as immediate when you stand up and stomp on the pedals like I imagined they would. On the other hand they're a lb lighter so maybe that

Quote:
What else do you want to ask on this forum? Like, is the Pope Catholic?

Alright wind y'er neck in, I only asked to see if anyone had any ideas to ascertain whether the wheels were flexing or if it's all in my head, or if they just feel different and I'm interpreting the lack of inertia as flex as they don't offer the resistance to push against whilst accelerating.

But the real question is, does he shit in the woods and are bears Catholic?
Quote:
So, you build with flexy DB spokes. You only use 28 at the back. You only use 24 at the front. Why would such wheels not be flexy?
Well it's 8 more front and 8 more rear than my last wheels which (I think) weren't :P

Quote:
The roules artile is a good one. Quote from part 3.

Yea, I can visualize that, a low spoke count and a stiff rim would allow the whole rim to flex relative to the hub, a flexy rim and lots of spokes would allow the lower half of the rim to flex while the upper half remains straight.

I run my pads quite close to the rim (<1mm), I usually build wheels and have them true in the stand, then put them in the bike and get the last 1/8th of a turn to get them perfect. I'm not convinced brake rub makes too much difference anyway, look at disk brakes, the pads are scuffing the rotor almost all the time with no measurable drag, time for a few wet rides I think to see if they're rubbing on the brakes anyway. If that's inconclusive I'll swap some tyres round and do some back to back tests with identical setups to see if I can feel the difference.


Top
 Profile  
 
Posted: Thu Nov 29, 2012 6:56 pm 


Top
  
 
PostPosted: Thu Nov 29, 2012 7:54 pm 
Offline
User avatar

Joined: Tue Jan 23, 2007 11:22 am
Posts: 3657
Location: Leg hurty
WMW wrote:
legs 11 wrote:
Don't go Ti spokes......period. They don't work. Every material has an ideal use in cycle engineering, but the combination of spoke and Ti is not a marriage made in heaven. :thumbup:


If they hold up, the NDS rear is an excellent place for them... if the hub has wide NDS spacing.

Ok, agreed, in situations where 'real world' conditions are not involved. For instance.... A one off pair of wheels for a hill climb etc. For a normal situation in European riding conditions Ti spokes are as good as useless.

_________________
Pedalling Law Student.


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 39 posts ] 
Go to page Previous  1, 2, 3  Next


Who is online

Users browsing this forum: Exabot [Bot], Google [Bot], iamalex, SWijland and 40 guests


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  

   Similar Topics   Author   Replies   Views   Last post 
This topic is locked, you cannot edit posts or make further replies. Wheel help

in Road

neilman01

3

458

Sat Oct 12, 2013 4:11 pm

WMW View the latest post

There are no new unread posts for this topic. 4za wheel decals

in Road

rbn1995

1

457

Sun Aug 11, 2013 11:50 am

sungod View the latest post

There are no new unread posts for this topic. Pulley wheel size

in Road

Nelus

2

534

Fri Aug 16, 2013 1:16 pm

Tenlegs View the latest post

There are no new unread posts for this topic. Wheel Suggestions Needed

[ Go to page: 1, 2 ]

in Road

ultimobici

23

1809

Fri Oct 25, 2013 7:31 pm

Calnago View the latest post

There are no new unread posts for this topic. Trainer wheel alternatives

in Road

seanblurr

2

249

Mon Mar 17, 2014 8:37 pm

G60 View the latest post


It is currently Sat Jul 26, 2014 8:40 am

All times are UTC + 1 hour




Advertising   –  FAQ   –  Contact   –  Convert   –  About

© Weight Weenies 2000-2013
hosted by starbike.com


How to get rid of these ads? Just register!


Powered by phpBB