Cycling and bicycle discussion forums. 
   Click here to join our community Log in to access your Control Panel  


Go Back   > >

Singlespeed & Fixed Gear "I still feel that variable gears are only for people over forty-five. Isn't it better to triumph by the strength of your muscles than by the artifice of a derailer? We are getting soft...As for me, give me a fixed gear!"-- Henri Desgrange (31 January 1865 - 16 August 1940)

User Tag List

Reply
 
Thread Tools Search this Thread
Old 07-24-08, 11:48 AM   #1
Sinn
Senior Member
Thread Starter
 
Join Date: Jul 2008
Bikes:
Posts: 1,064
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Sugino 75 vs. Truvativ Omnium (for Surly)

This is the continuation of another thread, which seems to have fallen off the radar screen for most of the bloggers here:

Sugino 75 vs. Truvativ Omnium

The discussion there has narrowed to the topic of whether the Truvativ Omnium or the Sugino 75 crankset is better for the Surly Steamroller frame. I think it is obvious that the Sugino cranks fit the Steamroller frame very well. I am looking for pics of Omnium cranks on Steamroller frames. Does anybody have one?

P.S. I know that some of you may think that deciding which cranks to get partially on the basis of aesthetic value is only for trendy, artsy cyclophiles who keep their bikes as a eunuch keeps a harem. I think that is a false assumption.
Sinn is offline   Reply With Quote
Old 07-24-08, 12:28 PM   #2
ksyrius
Senior Member
 
Join Date: Jul 2007
Bikes:
Posts: 125
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Edited, i was wrong in assuming the omniums werent going to be beefy enough, because as the pictures below show, the connections are quite thick and look to be strong enough for the street.

Last edited by ksyrius; 07-24-08 at 02:29 PM.
ksyrius is offline   Reply With Quote
Old 07-24-08, 12:31 PM   #3
andre nickatina
not actually Nickatina
 
andre nickatina's Avatar
 
Join Date: Oct 2006
Location: OR
Bikes:
Posts: 4,447
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by ksyrius View Post
I dont think you would want to ride the omnium anywhere but the track. Because of its design, that hollow axle that runs thruogh your bb shell is connected to your drive side crank with not much surface area, skids and stuff will take toll on that connection point, as well as the other side where the non drive side connects the hollow axle. Octalink under alot of stress will begin to wear away at the splines. I actually just had to replace my cranks because of this exact issue (octalink). And ive seen/heard of other people doing the same thing. I dont know if this is the same for isis, but i wouldnt be surprised.

Square taper is tried and true, and (yes) its true that even square taper can succumb to the stress of street riding and they will begin to spider where it connects to the bb, but i think if your between these two choices your best bet is the sugino 75's. They will probably last longer. Although i do believe the claim that truvativ makes saying the omniums are super stiff, which is a benefit to their hollow axle design. But in everyday use you probably wont notice any difference b/w the two.

Fixed riding on the street puts alot of stress on the frame near the bottom bracket, thats usually where the aluminum frames start to break. So i would be cautious using the new omniums if you make that choice.
You got ISIS confused with external BB. Also, Octalink does not equal external BB so it's unfair to draw comparisons there either. I'm going off Prolly - if anyone abuses equipment it's him and he gave me the go-ahead on riding Omniums on the street.
andre nickatina is offline   Reply With Quote
Old 07-24-08, 12:37 PM   #4
ksyrius
Senior Member
 
Join Date: Jul 2007
Bikes:
Posts: 125
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I guess what i was referring to was the type of spline connection that is used, yea its an external bb, but it still uses splines.
ksyrius is offline   Reply With Quote
Old 07-24-08, 12:45 PM   #5
Sinn
Senior Member
Thread Starter
 
Join Date: Jul 2008
Bikes:
Posts: 1,064
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
I've seen Prolly's Steamroller. Its a beast. But it has, I think, black
75's on it.
Sinn is offline   Reply With Quote
Old 07-24-08, 01:04 PM   #6
dutret
Banned
 
Join Date: May 2005
Location: GA
Bikes:
Posts: 5,317
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by ksyrius View Post
I guess what i was referring to was the type of spline connection that is used, yea its an external bb, but it still uses splines.
it does not use octalink splines though.
dutret is offline   Reply With Quote
Old 07-24-08, 01:09 PM   #7
ilive41
Senior Member
 
Join Date: Jul 2008
Bikes:
Posts: 54
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
The omniums are great for street use or track use, and will last a long time (not forever). So will Sugino 75's, and an argument can be made that they'll outlast the 75's. Research 7075 hardened aluminum (in general) for hardness and strength/durability... it'll outlast lesser cranks that last a lot of guys years.

My red SRAM box arrived this morning and the Omniums are presented well in the box. Beautiful crank set, and I actually REALLY like the chain ring... not sure what it costs on its own but it's very nice. 167.5 should give me tons of clearance on my 58cm, and I'll let ya'll know if/when they break. But for now, I'm in love. And I know the 75's are great cranks, but for the small price difference and 115g bottom bracket, I am well-pleased.
ilive41 is offline   Reply With Quote
Old 07-24-08, 01:24 PM   #8
ksyrius
Senior Member
 
Join Date: Jul 2007
Bikes:
Posts: 125
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
btw, im not trying to say the omniums are a horrible choice, i may be a little bias because i just had to replace my cranks because of the problems i described in my earlier post, which i believe any splined interface can experience if its gonna be run fixed on the street.

Last edited by ksyrius; 07-24-08 at 02:30 PM.
ksyrius is offline   Reply With Quote
Old 07-24-08, 01:31 PM   #9
andre nickatina
not actually Nickatina
 
andre nickatina's Avatar
 
Join Date: Oct 2006
Location: OR
Bikes:
Posts: 4,447
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by Sinn View Post
I've seen Prolly's Steamroller. Its a beast. But it has, I think, black
75's on it.
I was talking about his Concept before he sold it. He rode it all winter on those Omnium cranks/BB.
andre nickatina is offline   Reply With Quote
Old 07-24-08, 01:32 PM   #10
dutret
Banned
 
Join Date: May 2005
Location: GA
Bikes:
Posts: 5,317
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by ksyrius View Post
yea i know that its not octalink, i mentioned this in my first post. The only real difference between the two spline designs is the number of splines 8 for octalink 10 for isis. My critique of these cranks is part of a larger criticism of splined interfaces for connecting crank arms together, therefore it applies to external, internal as well as octalink and isis. If you havent seen one of these new external BB crank designs in person, check out this picture http://www.businesscycles.com/tcr-sram.htm its of the omnium and in it you can see what im talking about, how there is an isis interface on the other side of the hollow axle.

btw, im not trying to say the omniums are a horrible choice, i may be a little bias because i just had to replace my cranks because of the problems i described in my earlier post, which i believe any splined interface can experience if its gonna be run fixed on the street. Road, and track use should not cause any of the problems i mentioned.
The splines are shaped differently too. Octalink problems are well known and may largely have to do with user error. Generalizing on that to ISIS is not valid however especially since isis failures seem to be much less common. Most importantly the drive side of the omniums is not connected to the spindle with either system and your argument that it is connnected with "not much surface area" is just silly.
dutret is offline   Reply With Quote
Old 07-24-08, 01:40 PM   #11
ksyrius
Senior Member
 
Join Date: Jul 2007
Bikes:
Posts: 125
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
The splines are shaped differently too. Octalink problems are well known and may largely have to do with user error. Generalizing on that to ISIS is not valid however especially since isis failures seem to be much less common. Most importantly the drive side of the omniums is not connected to the spindle with either system and your argument that it is connnected with "not much surface area" is just silly.
Ok well ill concede that generalizing to isis is not valid, i guess im just expressing the initial reservations i had about the omnium track cranks. the "not much surface area" is referring to where the hollow axle is connected to the drive side arm. I used to have a set of truvativ hollow axle cranks on my road bike and the connection point between the hollow axle and the drive side arm looked pretty thin, it may be different for the omniums, but my common sense told me that under continued abuse it could be a failure point.
ksyrius is offline   Reply With Quote
Old 07-24-08, 02:22 PM   #12
ilive41
Senior Member
 
Join Date: Jul 2008
Bikes:
Posts: 54
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Not sure what you had before but I've got the Omniums on my desk. The hollow axle connects to the crank quite well... nice and thick. Iphone photos aren't the best, but I did what I could...








Attached Images
File Type: jpg IMG_0021.JPG (89.1 KB, 381 views)
File Type: jpg IMG_0022.JPG (85.2 KB, 375 views)
File Type: jpg IMG_0024.JPG (75.6 KB, 380 views)
File Type: jpg IMG_0025.JPG (87.3 KB, 375 views)
File Type: jpg IMG_0026.JPG (80.8 KB, 373 views)
ilive41 is offline   Reply With Quote
Old 07-24-08, 02:27 PM   #13
ksyrius
Senior Member
 
Join Date: Jul 2007
Bikes:
Posts: 125
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
That clears things up alot, because ive been looking for some pictures and could only find the default one that is supplied at the truvativ website which doesnt show much. Thats quite different than what i thought it would be, and in that case ill redact my criticism of the omniums because that connection does look really beefy. Thanks for the pictures.
ksyrius is offline   Reply With Quote
Old 07-24-08, 02:37 PM   #14
ilive41
Senior Member
 
Join Date: Jul 2008
Bikes:
Posts: 54
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
If I had a ruler I could have gone wild, but I need to work, since I'm at work and all.

Long story short, concerning the hollow axle and spline design, I am confident that both will be completely sufficient for daily fixed gear riding for a long time. It's beefy. In person it's pretty impressive and Truvativ could do themselves a lot of good to have better photos online.
ilive41 is offline   Reply With Quote
Old 07-24-08, 02:42 PM   #15
deadforkinglast
Senior Member
 
Join Date: Dec 2007
Bikes:
Posts: 413
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Why did you start another thread about this?

Once you had done that, why did you continue the other thread as well?
deadforkinglast is offline   Reply With Quote
Old 07-24-08, 02:46 PM   #16
Sinn
Senior Member
Thread Starter
 
Join Date: Jul 2008
Bikes:
Posts: 1,064
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
OK. Here is an argument I just got from my LBS guy. I should say that I really respect this guy as a cyclist and a mechanic. He has ridden in professional track and street racing for a long time. He knows his stuff. He says that despite what Truvativ says about the Omniums, they are still soft compared to the 75's. Now, granted, I (the puny street rider) won't be able to tell the difference now (but, hopefully, after years of busting my ass at the track and on the road, I will be able to), but there is a reason that track racers don't use Omniums: they 'give' more due to the spindle length (I know, there is no bottom bracket spindle here, just the bar connecting the two crank arms like on a road bike). The Sugino cranks are built to use a shorter spindle to reduce bending and the potential for breaking. The Omnium cranks are more likely to break due to the lenght of the spindle. And, they are going to give a softer pedal stroke due to the fact that the bearings are on the outside of the bracket casing. This is also why Suginos are NJS certified and Omniums are not. Therefore, Sugino's are a higher quality crank.

So, I think that this is a pretty good reason to go with Suginos. What do you all think?
Sinn is offline   Reply With Quote
Old 07-24-08, 02:48 PM   #17
Sinn
Senior Member
Thread Starter
 
Join Date: Jul 2008
Bikes:
Posts: 1,064
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by deadforkinglast View Post
Why did you start another thread about this?

Once you had done that, why did you continue the other thread as well?
Ummm. Because the old thread was always on the second page. I did not want the conversation to die yet. (I guess I don't understand the mechanics of this blog yet.)

Last edited by Sinn; 07-24-08 at 03:17 PM. Reason: I took out a naughty word.
Sinn is offline   Reply With Quote
Old 07-24-08, 03:18 PM   #18
ksyrius
Senior Member
 
Join Date: Jul 2007
Bikes:
Posts: 125
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
but there is a reason that track racers don't use Omniums: they 'give' more due to the spindle length (I know, there is no bottom bracket spindle here, just the bar connecting the two crank arms like on a road bike). The Sugino cranks are built to use a shorter spindle to reduce bending and the potential for breaking. The Omnium cranks are more likely to break due to the lenght of the spindle. And, they are going to give a softer pedal stroke due to the fact that the bearings are on the outside of the bracket casing. This is also why Suginos are NJS certified and Omniums are not. Therefore, Sugino's are a higher quality crank.
The omniums arent njs for alot of reasons bb design included, but to get njs certified for anything is a serious ordeal and i dont think youll ever see any njs cranks coming from companies other than sugino or shimano (campy doesnt count cus they dont do njs stuff anymore). also the only njs certified bb's are octalink and square taper

Last edited by ksyrius; 07-24-08 at 03:28 PM.
ksyrius is offline   Reply With Quote
Old 07-24-08, 03:19 PM   #19
shants
roll'em high
 
shants's Avatar
 
Join Date: Feb 2005
Location: columbus, ohio
Bikes:
Posts: 2,391
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by Sinn View Post
OK. Here is an argument I just got from my LBS guy. I should say that I really respect this guy as a cyclist and a mechanic. He has ridden in professional track and street racing for a long time. He knows his stuff. He says that despite what Truvativ says about the Omniums, they are still soft compared to the 75's. Now, granted, I (the puny street rider) won't be able to tell the difference now (but, hopefully, after years of busting my ass at the track and on the road, I will be able to), but there is a reason that track racers don't use Omniums: they 'give' more due to the spindle length (I know, there is no bottom bracket spindle here, just the bar connecting the two crank arms like on a road bike). The Sugino cranks are built to use a shorter spindle to reduce bending and the potential for breaking. The Omnium cranks are more likely to break due to the lenght of the spindle. And, they are going to give a softer pedal stroke due to the fact that the bearings are on the outside of the bracket casing. This is also why Suginos are NJS certified and Omniums are not. Therefore, Sugino's are a higher quality crank.

So, I think that this is a pretty good reason to go with Suginos. What do you all think?
This argument is quite flawed. Regardless of the length of the spindle, the fulcrum(s) (i.e.: the bearing contact points) are farther from the load (i.e.: the force of you pedaling) in the case of the Sugino 75, thereby increasing stress on the spindle and decreasing stiffness. In a traditional bottom bracket, the bearings sit recessed inside of the bottom bracket shell, whereas in the case of external setups, the bearings are situated closer to the crank arm. Just looking at my track bikes with traditional square taper setups, the bearings sometimes sit as far as 1cm away from the crank arm.Moreover, the primary advantage of outboard bearing bottom brackets is the ability to have a large diameter spindle without having to sacrifice the durability of larger ball bearings. The increased circumference of the "spindle" in the Omnium will increase stiffness and reduce "bending and the potential for breaking."

Quote:
And, they are going to give a softer pedal stroke due to the fact that the bearings are on the outside of the bracket casing.
As I have just noted, this will increase, not decrease, stiffness.

Quote:
This is also why Suginos are NJS certified and Omniums are not.
NJS certification has very little to do with performance; rather, standards exist so as to limit technical advantages among racers in a sport (Japanese keirin racing) that serves as a platform for gambling.

Now, none of this is to say that the Omniums are better cranks, but your decision to buy Sugino 75s shouldn't be based on such a sad argument. Not all mechanics and racers know what they are talking about.
shants is offline   Reply With Quote
Old 07-24-08, 03:26 PM   #20
Sinn
Senior Member
Thread Starter
 
Join Date: Jul 2008
Bikes:
Posts: 1,064
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by shants View Post
This argument is quite flawed. Regardless of the length of the spindle, the fulcrum(s) (i.e.: the bearing contact points) are farther from the load (i.e.: the force of you pedaling) in the case of the Sugino 75, thereby increasing stress on the spindle and decreasing stiffness. In a traditional bottom bracket, the bearings sit recessed inside of the bottom bracket shell, whereas in the case of external setups, the bearings are situated closer to the crank arm. Just looking at my track bikes with traditional square taper setups, the bearings sometimes sit as far as 1cm away from the crank arm.Moreover, the primary advantage of outboard bearing bottom brackets is the ability to have a large diameter spindle without having to sacrifice the durability of larger ball bearings. The increased circumference of the "spindle" in the Omnium will increase stiffness and reduce "bending and the potential for breaking."



As I have just noted, this will increase, not decrease, stiffness.



NJS certification has very little to do with performance; rather, standards exist so as to limit technical advantages among racers in a sport (Japanese keirin racing) that serves as a platform for gambling.

Now, none of this is to say that the Omniums are better cranks, but your decision to buy Sugino 75s shouldn't be based on such a sad argument. Not all mechanics and racers know what they are talking about.
Hmm. Interesting observations. I still think that there may be some difference in the amount of force the longer spindle on the Omniums can take. It is harder to break a shorter spindle. And the NJS does more than secure a fair betting arena. They also evaluate components according to whether they are safe for track use.

Last edited by Sinn; 07-24-08 at 03:30 PM. Reason: Clarifying. God! I gotta stop doing this!
Sinn is offline   Reply With Quote
Old 07-24-08, 04:24 PM   #21
mugatu
Senior Member
 
mugatu's Avatar
 
Join Date: Apr 2007
Location: DFW
Bikes:
Posts: 1,005
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
based on what that mechanic told you, I would go to a different mechanic from now on
any freshman ME student knows better
mugatu is offline   Reply With Quote
Old 07-24-08, 04:39 PM   #22
Soil_Sampler
A little North of Hell
 
Join Date: Mar 2006
Bikes:
Posts: 4,789
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 3 Post(s)
Quote:
Originally Posted by Sinn View Post
I still think that there may be some difference in the amount of force the longer spindle on the Omniums can take.
It is harder to break a shorter spindle.
When people perceive things to be true, In their mind they think they are true, even without empirical data to back it up.

It is also "harder" to break a larger diameter spindle.

If you want your thread to stay on the first page, bump it up.
Soil_Sampler is offline   Reply With Quote
Old 07-24-08, 04:52 PM   #23
Sinn
Senior Member
Thread Starter
 
Join Date: Jul 2008
Bikes:
Posts: 1,064
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by mugatu View Post
based on what that mechanic told you, I would go to a different mechanic from now on
any freshman ME student knows better
So, if the Truvativs are stiffer or equally as stiff as the Suginos, why are they not NJS certified? If freshmen are learning the concepts necessary to undermine the argument that this mechanic gave me, why has NJS not given a certification? Has Truvativ decided that this would not be a smart marketing move? Certainly not.
Sinn is offline   Reply With Quote
Old 07-24-08, 04:56 PM   #24
Jabba Degrassi
FNG
 
Jabba Degrassi's Avatar
 
Join Date: Nov 2007
Location: Toronto, ON
Bikes: 2008 IRO Angus, 2008 Jamis Exile 29er
Posts: 2,313
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by Sinn View Post
So, if the Truvativs are stiffer or equally as stiff as the Suginos, why are they not NJS certified? If freshmen are learning the concepts necessary to undermine the argument that this mechanic gave me, why has NJS not given a certification? Has Truvativ decided that this would not be a smart marketing move? Certainly not.
NJS=/=quality.

All it means is that the hardware conforms to the specifications set forth by the NJS for Keirin racing. That's it. Quality is obviously a concern, as low-quality hardware that is prone to failure create obvious safety concerns, but quality is not the only concern, and, arguably, not the main one. It's all about creating a safe and level playing field. It is NOT about singling out the best of the best of the best of the best hardware.
Jabba Degrassi is offline   Reply With Quote
Old 07-24-08, 05:08 PM   #25
Sinn
Senior Member
Thread Starter
 
Join Date: Jul 2008
Bikes:
Posts: 1,064
Mentioned: 0 Post(s)
Tagged: 0 Thread(s)
Quoted: 0 Post(s)
Quote:
Originally Posted by Soil_Sampler View Post
When people perceive things to be true, In their mind they think they are true, even without empirical data to back it up.

It is also "harder" to break a larger diameter spindle.

If you want your thread to stay on the first page, bump it up.
Ok. Here is an (empirical) argument for thinking that a shorter spindle is harder to break: Take two sticks of equal diameter. Make one such that it is half as long as the other. See which is harder to break. The shorter is harder to break. QED
Sinn is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off



All times are GMT -6. The time now is 08:54 PM.