Wheelbuilding - How much tension is enough?

[Luke Forward]

Hello fellows. I'm a amature wheelbuilder from Taiwan. Having a few
expriences in wheelbuilding but for somehow a little comfued with
spoke tension. Mostly, I build wheels with Alexrims 32H and DT plain
guage(14G), x3 pattern. I believe in the-higher-tension-the-better
theory but I can't get any official resource saying how high is too
high for a given rim.

I used to build it with DS 150kgf /NDS 80kgf and 100kgf for a front
wheel. They work fine so far, never heard any faulty feedback.

Rim I have built: Alexrims ACE-18, G2000 and other single wall modles.
MAVIC X221.

Is there a method I can determine the best tension for a given rim?
Or am I just not good enough at sourcing data?

any ideas?

 

[[email protected]]

Luke Forward writes:

> I'm a amature wheelbuilder from Taiwan. Having a few expriences in
> wheelbuilding but for somehow a little comfued with spoke tension.
> Mostly, I build wheels with Alexrims 32H and DT plain guage(14G), x3
> pattern. I believe in the-higher-tension-the-better theory but I
> can't get any official resource saying how high is too high for a
> given rim.

> I used to build it with DS 150kgf /NDS 80kgf and 100kgf for a front
> wheel. They work fine so far, never heard any faulty feedback.

> Rim I have built: Alexrims ACE-18, G2000 and other single wall
> modles. MAVIC X221.

> Is there a method I can determine the best tension for a given rim?
> Or am I just not good enough at sourcing data?

Before any rim manufacturers listed maximum tension, and I still don't
see where they get their numbers, a method was outlined in "the
Bicycle Wheel" that comes up here in this newsgroup by doubters.

http://tinyurl.com/22v535

This method has been useful for double walled rims that have eyelets
and sockets. After rims began cracking and losing spoke tension
because they had no sockets that distribute spoke loads, tension
specifications were introduced. However, these did not stop rims from
cracking at spoke holes.

Jobst Brandt

 

[Ozark Bicycle]

On Jan 7, 9:55 am, [email protected] wrote:
> Luke Forward writes:
> > I'm a amature wheelbuilder from Taiwan.  Having a few expriences in
> > wheelbuilding but for somehow a little comfued with spoke tension.
> > Mostly, I build wheels with Alexrims 32H and DT plain guage(14G), x3
> > pattern.  I believe in the-higher-tension-the-better theory but I
> > can't get any official resource saying how high is too high for a
> > given rim.
> > I used to build it with DS 150kgf /NDS 80kgf and 100kgf for a front
> > wheel.  They work fine so far, never heard any faulty feedback.
> > Rim I have built: Alexrims ACE-18, G2000 and other single wall
> > modles.  MAVIC X221.
> > Is there a method I can determine the best tension for a given rim?
> > Or am I just not good enough at sourcing data?
>
> Before any rim manufacturers listed maximum tension, and I still don't
> see where they get their numbers,

Perhaps they [rim manufacturers] get "their numbers" [for maximum
spoke tension] by running the tension up until the rim bed fails under
actual use. IOW, they test their product.


> a method was outlined in "the
> Bicycle Wheel" that comes up here in this newsgroup by doubters.
>
>  http://tinyurl.com/22v535

Have you updated that book to reflect the *reality* of currently
available rims built to modern configurations (IOW, highly dished
130mm o/l/d 9/10sp rear wheels)?


>
> This method has been useful for double walled rims that have eyelets
> and sockets.  After rims began cracking and losing spoke tension
> because they had no sockets that distribute spoke loads, tension
> specifications were introduced.  However, these did not stop rims from
> cracking at spoke holes.
>

Classic OSAF.

 

[Mike Jacoubowsky]

>Have you updated that book to reflect the *reality* of currently
>available rims built to modern configurations (IOW, highly dished
>130mm o/l/d 9/10sp rear wheels)?

Highly-dished wheels are nothing new. Putting "ultra-6" freewheels on 120mm
hubs generally required an extra 1mm spacer on the freewheel side, and the
126mm 8-speed systems were dreadfully overdished.

--Mike--
Chain Reaction Bicycles
www.ChainReaction.com


"Ozark Bicycle" <[email protected]> wrote in message
news:[email protected]...
On Jan 7, 9:55 am, [email protected] wrote:
> Luke Forward writes:
> > I'm a amature wheelbuilder from Taiwan. Having a few expriences in
> > wheelbuilding but for somehow a little comfued with spoke tension.
> > Mostly, I build wheels with Alexrims 32H and DT plain guage(14G), x3
> > pattern. I believe in the-higher-tension-the-better theory but I
> > can't get any official resource saying how high is too high for a
> > given rim.
> > I used to build it with DS 150kgf /NDS 80kgf and 100kgf for a front
> > wheel. They work fine so far, never heard any faulty feedback.
> > Rim I have built: Alexrims ACE-18, G2000 and other single wall
> > modles. MAVIC X221.
> > Is there a method I can determine the best tension for a given rim?
> > Or am I just not good enough at sourcing data?
>
> Before any rim manufacturers listed maximum tension, and I still don't
> see where they get their numbers,

Perhaps they [rim manufacturers] get "their numbers" [for maximum
spoke tension] by running the tension up until the rim bed fails under
actual use. IOW, they test their product.


> a method was outlined in "the
> Bicycle Wheel" that comes up here in this newsgroup by doubters.
>
> http://tinyurl.com/22v535

Have you updated that book to reflect the *reality* of currently
available rims built to modern configurations (IOW, highly dished
130mm o/l/d 9/10sp rear wheels)?


>
> This method has been useful for double walled rims that have eyelets
> and sockets. After rims began cracking and losing spoke tension
> because they had no sockets that distribute spoke loads, tension
> specifications were introduced. However, these did not stop rims from
> cracking at spoke holes.
>

Classic OSAF.

 

[Ozark Bicycle]

On Jan 7, 8:41 pm, "Mike Jacoubowsky" <[email protected]> wrote:
> >Have you updated that book to reflect the *reality* of currently
> >available rims built to modern configurations (IOW, highly dished
> >130mm o/l/d 9/10sp rear wheels)?
>
> Highly-dished wheels are nothing new. Putting "ultra-6" freewheels on 120mm
> hubs generally required an extra 1mm spacer on the freewheel side, and the
> 126mm 8-speed systems were dreadfully overdished.
>

Proving that Brandt is even in more dire need of updating??? ;-)

Seriously, though, IIRC, "ultra-6" FWs occupied the same space as a
5sp FW. And 126mm 8sp wheels were never all that common.

 

[Chalo]

Mike Jacoubowsky wrote:
>
> Perhaps they [rim manufacturers] get "their numbers" [for maximum
> spoke tension] by running the tension up until the rim bed fails under
> actual use. IOW, they test their product.

That seems wildly unlikely considering that recommended tensions for
hefty touring and downhill MTB rims tend to be similar if not
identical to the recommended tensions for lightweight road rims. If
the recommendations are the results of any kind of testing, they are
simply designing the rims wrong.

Chalo

 

[jim beam]

Chalo wrote:
> Mike Jacoubowsky wrote:
>> Perhaps they [rim manufacturers] get "their numbers" [for maximum
>> spoke tension] by running the tension up until the rim bed fails under
>> actual use. IOW, they test their product.
>
> That seems wildly unlikely considering that recommended tensions for
> hefty touring and downhill MTB rims tend to be similar if not
> identical to the recommended tensions for lightweight road rims. If
> the recommendations are the results of any kind of testing, they are
> simply designing the rims wrong.

how can that be? structurally, the only tension you need is that
sufficient to prevent spokes going slack. [and even then, the primary
driver of that is spoke nipple unscrewing.] tensioning higher than that
achieves nothing structurally - certainly not increasing wheel strength.
and with a highly dished wheel, such tension is not even possible! so
in the real world, we're forced to compromise [shock horror - /real/
engineers do this all the time] and use a spoke tension that is found to
work in practice. that spoke tension for a "truck" rim is not higher
than a lightweight road racing rim is simply recognition of engineering
reality [stiffer rims deform less and thus, spokes are less inclined to
go slack], not sticking to underinformed, conceptually challenged
jobstian dogma.

 

[jim beam]

Ozark Bicycle wrote:
> On Jan 7, 9:55�am, [email protected] wrote:
>> Luke Forward writes:
>>> I'm a amature wheelbuilder from Taiwan. �Having a few expriences in
>>> wheelbuilding but for somehow a little comfued with spoke tension.
>>> Mostly, I build wheels with Alexrims 32H and DT plain guage(14G), x3
>>> pattern. �I believe in the-higher-tension-the-better theory but I
>>> can't get any official resource saying how high is too high for a
>>> given rim.
>>> I used to build it with DS 150kgf /NDS 80kgf and 100kgf for a front
>>> wheel. �They work fine so far, never heard any faulty feedback.
>>> Rim I have built: Alexrims ACE-18, G2000 and other single wall
>>> modles. �MAVIC X221.
>>> Is there a method I can determine the best tension for a given rim?
>>> Or am I just not good enough at sourcing data?
>> Before any rim manufacturers listed maximum tension, and I still don't
>> see where they get their numbers,
>
> Perhaps they [rim manufacturers] get "their numbers" [for maximum
> spoke tension] by running the tension up until the rim bed fails under
> actual use. IOW, they test their product.

come now - you can't possibly expect a manufacturer to be responsible
enough to actually /test/ their product can you? i mean, all they have
to do is read "the book" to learn that if they can somehow just keep
increasing spoke tension, their rims get magically stronger and stronger
- no penalties incurred. spending time on research and money on
testing? what a waste! unless they're stupid enough to anodize their
rims of course - we all know that /that/ is what really cracks rims -
not inability to understand the whole
structural/tension/anisotropy/strength of materials concept.


>
>
>> a method was outlined in "the
>> Bicycle Wheel" that comes up here in this newsgroup by doubters.

not doubters of the benefits of bedding spokes into soft aluminum hubs
[and rims] so that wheels remain true in use. otoh, those daring to
point out obvious flaws in structural theory or materials theory can be
ridiculed as unbelievers. like engineering is a matter of faith and
extrapolation from insufficient conceptual understanding.


>>
>> �http://tinyurl.com/22v535
>
> Have you updated that book to reflect the *reality* of currently
> available rims built to modern configurations (IOW, highly dished
> 130mm o/l/d 9/10sp rear wheels)?
>
>
>> This method has been useful for double walled rims that have eyelets
>> and sockets. �After rims began cracking and losing spoke tension
>> because they had no sockets that distribute spoke loads, tension
>> specifications were introduced. �However, these did not stop rims from
>> cracking at spoke holes.
>>
>
> Classic OSAF.
>

 

[jim beam]

Luke Forward wrote:
> Hello fellows. I'm a amature wheelbuilder from Taiwan. Having a few
> expriences in wheelbuilding but for somehow a little comfued with
> spoke tension. Mostly, I build wheels with Alexrims 32H and DT plain
> guage(14G), x3 pattern. I believe in the-higher-tension-the-better
> theory but I can't get any official resource saying how high is too
> high for a given rim.

yes you can - rim manufacturers publish max tension data. and the
"the-higher-tension-the-better" theory is flawed since it's based on a
one-sided consideration of the wheel spokes, and doesn't take account of
how increasing spoke tension affects the rim.


>
> I used to build it with DS 150kgf /NDS 80kgf and 100kgf for a front
> wheel. They work fine so far, never heard any faulty feedback.
>
> Rim I have built: Alexrims ACE-18, G2000 and other single wall modles.
> MAVIC X221.
>
> Is there a method I can determine the best tension for a given rim?
> Or am I just not good enough at sourcing data?
>
> any ideas?

some data is available by googling this group. other is available from
the manufacturer direct. phone, email or search their websites.

 

[[email protected]]

On Mon, 7 Jan 2008 07:23:32 -0800 (PST), Luke Forward
<[email protected]> wrote:

>Hello fellows. I'm a amature wheelbuilder from Taiwan. Having a few
>expriences in wheelbuilding but for somehow a little comfued with
>spoke tension. Mostly, I build wheels with Alexrims 32H and DT plain
>guage(14G), x3 pattern. I believe in the-higher-tension-the-better
>theory but I can't get any official resource saying how high is too
>high for a given rim.
>
>I used to build it with DS 150kgf /NDS 80kgf and 100kgf for a front
>wheel. They work fine so far, never heard any faulty feedback.
>
>Rim I have built: Alexrims ACE-18, G2000 and other single wall modles.
>MAVIC X221.
>
>Is there a method I can determine the best tension for a given rim?
>Or am I just not good enough at sourcing data?
>
>any ideas?

Dear Luke,

For whatever it's worth, Alex recommends various tensions in this FAQ:
http://www.alexrims.com/support.asp?btn=11&cat=8#1

You could email them if the rims that interest you aren't mentioned.

Cheers,

Carl Fogel

 

[daveornee]

Hello fellows. I'm a amature wheelbuilder from Taiwan. Having a few
expriences in wheelbuilding but for somehow a little comfued with
spoke tension. Mostly, I build wheels with Alexrims 32H and DT plain
guage(14G), x3 pattern. I believe in the-higher-tension-the-better
theory but I can't get any official resource saying how high is too
high for a given rim.

I used to build it with DS 150kgf /NDS 80kgf and 100kgf for a front
wheel. They work fine so far, never heard any faulty feedback.

Rim I have built: Alexrims ACE-18, G2000 and other single wall modles.
MAVIC X221.

Is there a method I can determine the best tension for a given rim?
Or am I just not good enough at sourcing data?

any ideas?

"Rim manufacturers have set tension recommendations from as low as 80 Kilograms Force to as high as 230 Kilograms force. Generally, the heavier and strong the rim, the more tension it can handle. A light rim may be weight from 280 grams to 350 grams. A heavy rim may be said to weigh 450 grams or more. Additionally, rim eyelets may help distribute the load on the rim wall. A lack on eyelets on a light rim may imply less spoke tension is required. Always consult the rim manufacture for the most up to date specifications. Note that these manufactuers give specification for the wheel without tire, or without inflated tire. Tire pressure will have the effect of lowering the tension of the wheel. Generally, do not try to account for this drop by adding more tension then recommended by the manufacturer.

Below are some specifications:Brand or Manufacturer Model Front wheel
NOTE: measure rotor side
if a disc hub Rear Wheel- right side (chain side)
Bontrager® Race X Lite Aero Carbon 91 to 136 Kgf 122 to 181 Kgf
Race X Lite Aero 91 to 136 Kgf 122 to 181 Kgf
Race X Lite 94 to 136 Kgf 122 to 181 Kgf
Race Lite Tandem 100 to 159 Kgf 100 to 150 Kgf
Race Lite 77 to 127 Kgf 86 to 159 Kgf
Race X Lite ATB 50 to 132 Kgf not availabe
Race Lite 29-inch ATB , Race Lite 29-inch Disc Compatible
2003 Race Lite Tubeless, Race Lite Tubeless Disc Specific
Race Tubeless, Race 29-inch Disc Compatible
Select Disc Compatible, Select ATB
Select Hybrid, Select road 50 to 132 Kgf 50 to 132 Kgf
Superstock 29-inch Disc Compatible 54 to 132 Kgf 54 to 132 Kgf
Superstock Disc Compatible 54 to 132 Kgf 54 to 132 Kgf
Superstock 54 to 132 Kgf 54 to 132 Kgf
Campagnolo® Eurus Wheel 60-80 Kgf 95-115 Kgf
Neutron Wheel 60-70 Kgf 120 to 140 Kgf
Hyperon Wheel 60-80 Kgf 110 to 130 Kgf
Proton Wheel 50 to 70 Kgf 120 to 140 Kgf
Scirocco Wheel 60 to 80 Kgf 85 to 105 Kgf
Zonda tangent spokes 60 to 80 Kgf
radial spoke 75 to 95 Kgf 90 to 110 Kgf
Mavic® Crossride® Ceramic 70 - 90 Kgf 70 - 90 Kgf
Crossride® Disc 90- 125 Kgf 115 - 145 Kgf
Classics SSC® 80 - 100 Kgf 80 - 100 Kgf
Crossroc® UST®, Crossroc UST® Disc 90 - 120 Kgf 90 - 120 Kgf
Cosmic® Elite 110 to 140 kgf 110 to 140 kgf
Ksyrium® Elite 100-130 Kgf 120-145 Kgf
Ksyrium SSC 90 - 110 kgf 130 - 150 kgf
Crossmax SL Disc 07
and SLR Disc
110 -145 kgf 115 - 150kgf
Crossmax® ST Disc 115- 150 Kgf 115 - 150 Kgf
Crossmax ST
105-150 kgf 115-150 kgf
Crossmax SLR Disc LEFTY 110 - 145 kgf ---
Crossmax® SLR 100 - 130 kgf 115 - 150 kgf
Crossmax® SX 105 - 150 kgf 105 - 150 kgf
Crosstrail &
Crosstrail Disc 90-125kgf 110-140kgf
Cosmic® Carbone SL Premium ® 105-145 kgf 120-160 kgf
Cosmic® Carbone SSC® --- 130-150 kgf
Cosmos® --- 100-120 kgf
Shimano® Wheels WH-M959, WH-M575, WH-M540 98 to 118 Kgf 105 to 128 Kgf
WH-M7701 (also for carbon) 105 to 160 Kgf 98 to 140 Kgf
WH-7700 and 6500 98 to 118 Kgf 105 to 128 Kgf"


Quoted from the Park Tool Website:


http://www.parktool.com/repair/readhowto.asp?id=128

You should call the manufacturer(s) directly for the specific models you are dealing with.

 

[Chalo]

On Jan 7, 9:22 pm, jim beam <[email protected]> wrote:
>
> so
> in the real world, we're forced to compromise [shock horror - /real/
> engineers do this all the time] and use a spoke tension that is found to
> work in practice.

In this case, I think the "compromise" is to establish a tension that
won't summarily collapse the manufacturer's flimsiest rim, and then
recommend it for all the rims regardless of intended load or rim cross-
section or spoke bed thickness or hoop diameter.

> that spoke tension for a "truck" rim is not higher
> than a lightweight road racing rim is simply recognition of engineering
> reality [stiffer rims deform less and thus, spokes are less inclined to
> go slack], not sticking to underinformed, conceptually challenged
> jobstian dogma.

Out here in the real world, heavier rims that carry heavier loads get
higher tension, just as they should. This puts the manufacturer's
tension recommendations into the same bin with fine print of the
"warranty void if actually used for anything" variety.

Chalo

 

[jim beam]

Chalo wrote:
> On Jan 7, 9:22 pm, jim beam <[email protected]> wrote:
>> so
>> in the real world, we're forced to compromise [shock horror - /real/
>> engineers do this all the time] and use a spoke tension that is found to
>> work in practice.
>
> In this case, I think the "compromise" is to establish a tension that
> won't summarily collapse the manufacturer's flimsiest rim, and then
> recommend it for all the rims regardless of intended load or rim cross-
> section or spoke bed thickness or hoop diameter.

"collapse" is insufficient criteria - as decades of jobstian
over-tension induced rim cracking evidence.


>
>> that spoke tension for a "truck" rim is not higher
>> than a lightweight road racing rim is simply recognition of engineering
>> reality [stiffer rims deform less and thus, spokes are less inclined to
>> go slack], not sticking to underinformed, conceptually challenged
>> jobstian dogma.
>
> Out here in the real world, heavier rims that carry heavier loads get
> higher tension,

you contradict yourself.


> just as they should. This puts the manufacturer's
> tension recommendations into the same bin with fine print of the
> "warranty void if actually used for anything" variety.

so you don't pay attention to the specs the engineers provide you when
machining airplane components? tell me, what kinds of planes have you
worked on parts for, and what do i need to avoid?

 

[Mike Jacoubowsky]

"Seriously, though, IIRC, "ultra-6" FWs occupied the same space as a
5sp FW. And 126mm 8sp wheels were never all that common."

The ultra-6 mechanism billed itself as being able to fit into the same
space, but reality proved otherwise. They were a bit wider, and (depending
upon the hub) often required either the use of an additional 1mm spacer on
the freewheel side, or filing away the inside of the chainstay/dropout
junction a bit, or both.

--Mike-- Chain Reaction Bicycles
www.ChainReactionBicycles.com


"Ozark Bicycle" <[email protected]> wrote in message
news:e7b21a29-ac72-43b5-ac25-e46e8a663061@e25g2000prg.googlegroups.com...
On Jan 7, 8:41 pm, "Mike Jacoubowsky" <[email protected]> wrote:
> >Have you updated that book to reflect the *reality* of currently
> >available rims built to modern configurations (IOW, highly dished
> >130mm o/l/d 9/10sp rear wheels)?
>
> Highly-dished wheels are nothing new. Putting "ultra-6" freewheels on
> 120mm
> hubs generally required an extra 1mm spacer on the freewheel side, and the
> 126mm 8-speed systems were dreadfully overdished.
>

Proving that Brandt is even in more dire need of updating??? ;-)

Seriously, though, IIRC, "ultra-6" FWs occupied the same space as a
5sp FW. And 126mm 8sp wheels were never all that common.

 

[Luke Forward]

On 1$B7n(B8$BF|(B, $B2<8a(B12$B;~(B16$BJ,(B, [email protected] wrote:
> Dear Luke,
>
> For whatever it's worth, Alex recommends various tensions in this FAQ:
> http://www.alexrims.com/support.asp?btn=11&cat=8#1
>
> You could email them if the rims that interest you aren't mentioned.
>
> Cheers,
>
> Carl Fogel

Thank for replying, Carl.
I checked that webpage monthes ago and at that time there wasn't much
information available.
And yes, I should have had mailed the manufacturor beforehand.

To other builders, despite argueing spoke tension theory, would you
mind sharing your preference on tension with specific wheel?
I think it's logical to give diffrent tension due to different lacing
pattern and components(rim, hub, spoke etc.)
Again, if you don't mind, share your wheel spec.

 

[Ozark Bicycle]

On Jan 7, 10:42 pm, "Mike Jacoubowsky" <[email protected]> wrote:
> "Seriously, though, IIRC, "ultra-6" FWs occupied the same space as a
> 5sp FW. And 126mm 8sp wheels were never all that common."
>
> The ultra-6 mechanism billed itself as being able to fit into the same
> space, but reality proved otherwise. They were a bit wider, and (depending
> upon the hub) often required either the use of an additional 1mm spacer on
> the freewheel side, or filing away the inside of the chainstay/dropout
> junction a bit, or both.
>

Ultra-6 was a long time ago and my recollections are a bit foggy; I
guess we differ around the term "often required". My recollection was
being able to unscrew the original 5sp FW and swap in an Ultra-6
cleanly and simply. I'm sure you're correct that certain hubs,
dropouts, etc., required more fussing.

 

[jim beam]

Luke Forward wrote:
> On 1$B7n(B8$BF|(B, $B2<8a(B12$B;~(B16$BJ,(B, [email protected] wrote:
>> Dear Luke,
>>
>> For whatever it's worth, Alex recommends various tensions in this FAQ:
>> http://www.alexrims.com/support.asp?btn=11&cat=8#1
>>
>> You could email them if the rims that interest you aren't mentioned.
>>
>> Cheers,
>>
>> Carl Fogel
>
> Thank for replying, Carl.
> I checked that webpage monthes ago and at that time there wasn't much
> information available.
> And yes, I should have had mailed the manufacturor beforehand.
>
> To other builders, despite argueing spoke tension theory, would you
> mind sharing your preference on tension with specific wheel?
> I think it's logical to give diffrent tension due to different lacing
> pattern and components(rim, hub, spoke etc.)

hub makes no difference. lacing makes no difference. spoke count makes
no difference. tension is a determined by the rim manufacturer only.
they all have specs for their products.

> Again, if you don't mind, share your wheel spec.

 

[Mark]

Ozark Bicycle wrote:
> On Jan 7, 10:42 pm, "Mike Jacoubowsky" <[email protected]> wrote:
>> "Seriously, though, IIRC, "ultra-6" FWs occupied the same space as a
>> 5sp FW. And 126mm 8sp wheels were never all that common."
>>
>> The ultra-6 mechanism billed itself as being able to fit into the same
>> space, but reality proved otherwise. They were a bit wider, and (depending
>> upon the hub) often required either the use of an additional 1mm spacer on
>> the freewheel side, or filing away the inside of the chainstay/dropout
>> junction a bit, or both.
>>
>
> Ultra-6 was a long time ago and my recollections are a bit foggy; I
> guess we differ around the term "often required". My recollection was
> being able to unscrew the original 5sp FW and swap in an Ultra-6
> cleanly and simply. I'm sure you're correct that certain hubs,
> dropouts, etc., required more fussing.

When I swapped my six-speed standard for a SunTour ultra-7, I had to add
a 1mm spacer on the right to keep the chain from grinding on the dropout
(1981 Raleigh Pro, Campy dropout). Not exactly the same thing as you
and Mike are arguing, but I would tend to believe Mike on this based on
my experience.

Granted, the Raleigh's dropout is now perilously close to the smallest
9-speed cog I currently have on the bike (rear triangle "sprung" rather
than being realigned to 130), so maybe this bike is an exceptional case.

Mark J.

 

[Ozark Bicycle]

On Jan 8, 10:15 am, Mark <[email protected]>
wrote:
> Ozark Bicycle wrote:
> > On Jan 7, 10:42 pm, "Mike Jacoubowsky" <[email protected]> wrote:
> >> "Seriously, though, IIRC, "ultra-6" FWs occupied the same space as a
> >> 5sp FW. And 126mm 8sp wheels were never all that common."
>
> >> The ultra-6 mechanism billed itself as being able to fit into the same
> >> space, but reality proved otherwise. They were a bit wider, and (depending
> >> upon the hub) often required either the use of an additional 1mm spaceron
> >> the freewheel side, or filing away the inside of the chainstay/dropout
> >> junction a bit, or both.
>
> > Ultra-6 was a long time ago and my recollections are a bit foggy; I
> > guess we differ around the term "often required". My recollection was
> > being able to unscrew the original 5sp FW and swap in an Ultra-6
> > cleanly and simply. I'm sure you're correct that certain hubs,
> > dropouts, etc., required more fussing.
>
> When I swapped my six-speed standard for a SunTour ultra-7, I had to add
> a 1mm spacer on the right to keep the chain from grinding on the dropout
> (1981 Raleigh Pro, Campy dropout).  Not exactly the same thing as you
> and Mike are arguing, but I would tend to believe Mike on this based on
> my experience.

OTOH, I swapped 5sp FWs for Ultra-5 FWs on a few bikes "way back when"
without any action than unscrewing the 5sp and screwing on the
Ultra-6.

Also, an Ultra-7sp *is* noticeably
wider than a "standard" 6sp; 5sp and Ultra-6 are much closer - that
was part of the original intent of the design.
>
> Granted, the Raleigh's dropout is now perilously close to the smallest
> 9-speed cog I currently have on the bike (rear triangle "sprung" rather
> than being realigned to 130), so maybe this bike is an exceptional case.
>
> Mark J.

 

[A Muzi]

>>> Seriously, though, IIRC, "ultra-6" FWs occupied the same space as a
>>> 5sp FW. And 126mm 8sp wheels were never all that common.

> "Mike Jacoubowsky" <[email protected]> wrote:
>> The ultra-6 mechanism billed itself as being able to fit into the same
>> space, but reality proved otherwise. They were a bit wider, and (depending
>> upon the hub) often required either the use of an additional 1mm spacer on
>> the freewheel side, or filing away the inside of the chainstay/dropout
>> junction a bit, or both.

Ozark Bicycle wrote:
> Ultra-6 was a long time ago and my recollections are a bit foggy; I
> guess we differ around the term "often required". My recollection was
> being able to unscrew the original 5sp FW and swap in an Ultra-6
> cleanly and simply. I'm sure you're correct that certain hubs,
> dropouts, etc., required more fussing.

Japanese five speeds generally ran a slightly (1~2mm) wider right side
spacing than Euro freewheels.
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971