Chain idler efficiency - roller vs. toothed



M

Mark

Guest
TandemFan wrote:
> We have a Rans Screamer tandem and there are a few idler rollers for
> the chain. An outfit sells toothed idlers for about $250:
> http://www.terracycle.com/Merchant2...oduct_Code=IdlRansScr&Category_Code=IdlersALL
>
> They have a long blurb on why they are better:
>
> http://www.terracycle.com/Merchant2/merchant.mvc?Screen=CTGY&Store_Code=T&Category_Code=IdlersALL
>
> What's the scoop? Does it make any difference at all, or are we going
> to go faster?
>
> Thanks!


May be valuable, I dunno, but this sentence on their site was a red flag
for me:

"Idlers are the bread and butter of TerraCycle"

Judging from the price, I can see that. Do they mean it solely in the
positive way, or is it a Freudian slip?

Mark J.
 
On Apr 25, 5:06 am, TandemFan <[email protected]> wrote:
> We have a Rans Screamer tandem and there are a few idler rollers for
> the chain.  An outfit sells toothed idlers for about $250:http://www.terracycle.com/Merchant2/merchant.mvc?Screen=PROD&Store_Co...
>
> They have a long blurb on why they are better:
>
> http://www.terracycle.com/Merchant2/merchant.mvc?Screen=CTGY&Store_Co...
>
> What's the scoop?  Does it make any difference at all, or are we going
> to go faster?
>
> Thanks!


I got one of their pulleys for my Burley Django, because the factory
one wore through in the middle. Good material for a long lifetime,
cheap material for more frequent replacements.

I would think high quality bearings in the jockey pulleys in the rear
derailer would make a bit of a difference.
 
L

Leo Lichtman

Guest
"TandemFan" wrote: (clip) Does it make any difference at all, or are we
going
> to go faster?

^^^^^^^^^^^^^^^^^^^^
Take $250 ot of your pocket, and the weight reduction will actually give you
the same speed increase*. A LOT more if you do in in small change.
__________________
*We are talking about a small change, aren't we? '-)
 
On Fri, 25 Apr 2008 06:06:14 -0400, TandemFan <[email protected]>
wrote:

>We have a Rans Screamer tandem and there are a few idler rollers for
>the chain. An outfit sells toothed idlers for about $250:
>http://www.terracycle.com/Merchant2...oduct_Code=IdlRansScr&Category_Code=IdlersALL
>
>They have a long blurb on why they are better:
>
>http://www.terracycle.com/Merchant2/merchant.mvc?Screen=CTGY&Store_Code=T&Category_Code=IdlersALL
>
>What's the scoop? Does it make any difference at all, or are we going
>to go faster?
>
>Thanks!


Dear TF,

Note the absence of any figures to back up the claims of significant
power losses.

Cheers,

Carl Fogel
 
T

Tom Sherman

Guest
TandemFan wrote:

[cross-posted to ARBR for Perry Butler's amusement]

> We have a R[ANS] Screamer tandem and there are a few idler rollers for
> the chain. An outfit sells toothed idlers for about $250:
> http://www.terracycle.com/Merchant2...oduct_Code=IdlRansScr&Category_Code=IdlersALL
>
> They have a long blurb on why they are better:
>
> http://www.terracycle.com/Merchant2/merchant.mvc?Screen=CTGY&Store_Code=T&Category_Code=IdlersALL
>
> What's the scoop? Does it make any difference at all, or are we going
> to go faster?
>

Someone needs to tell Pat Franz that it is "RANS" and not "Rans".

While the manufacturers in question are trying to meet a price point for
their bicycles, they are not going to be putting junk chain idlers on
their bicycles [1]. Therefore, while there is room for improvement, the
gains will likely be small as drive-train friction is a small component
of total non-conservative losses, even on a recumbent with a complicated
chain-line.

If you want to make a RANS Screamer a lot faster than stock, put a front
fairing (Zzipper or Mueller) and a bodysock on the bike.

[1] Unlike some defunct manufacturers of the past.

--
Tom Sherman - Holstein-Friesland Bovinia
The weather is here, wish you were beautiful
 
J

Jon Bendtsen

Guest
Tom Sherman wrote:
> TandemFan wrote:
>
> [cross-posted to ARBR for Perry Butler's amusement]
>
>> We have a R[ANS] Screamer tandem and there are a few idler rollers for
>> the chain. An outfit sells toothed idlers for about $250:
>> http://www.terracycle.com/Merchant2...oduct_Code=IdlRansScr&Category_Code=IdlersALL
>>
>>
>> They have a long blurb on why they are better:
>>
>> http://www.terracycle.com/Merchant2/merchant.mvc?Screen=CTGY&Store_Code=T&Category_Code=IdlersALL
>>
>>
>> What's the scoop? Does it make any difference at all, or are we going
>> to go faster?
>>

> Someone needs to tell Pat Franz that it is "RANS" and not "Rans".
>
> While the manufacturers in question are trying to meet a price point for
> their bicycles, they are not going to be putting junk chain idlers on
> their bicycles [1]. Therefore, while there is room for improvement, the
> gains will likely be small as drive-train friction is a small component
> of total non-conservative losses, even on a recumbent with a complicated
> chain-line.


Why not avoid idlers and recumbents with complicated chain-lines?

It might not (yet) be possible with a tandem, but for a single
rider bike, cruzbike offers a short normal chain-line.


JonB
 
T

Tom Sherman

Guest
Jon Bendtsen wrote:
> Tom Sherman wrote:
>> TandemFan wrote:
>>
>> [cross-posted to ARBR for Perry Butler's amusement]
>>
>>> We have a R[ANS] Screamer tandem and there are a few idler rollers for
>>> the chain. An outfit sells toothed idlers for about $250:
>>> http://www.terracycle.com/Merchant2...oduct_Code=IdlRansScr&Category_Code=IdlersALL
>>>
>>>
>>> They have a long blurb on why they are better:
>>>
>>> http://www.terracycle.com/Merchant2/merchant.mvc?Screen=CTGY&Store_Code=T&Category_Code=IdlersALL
>>>
>>>
>>> What's the scoop? Does it make any difference at all, or are we going
>>> to go faster?
>>>

>> Someone needs to tell Pat Franz that it is "RANS" and not "Rans".
>>
>> While the manufacturers in question are trying to meet a price point
>> for their bicycles, they are not going to be putting junk chain idlers
>> on their bicycles [1]. Therefore, while there is room for improvement,
>> the gains will likely be small as drive-train friction is a small
>> component of total non-conservative losses, even on a recumbent with a
>> complicated chain-line.

>
> Why not avoid idlers and recumbents with complicated chain-lines?
>
> It might not (yet) be possible with a tandem, but for a single
> rider bike, cruzbike offers a short normal chain-line.
>

And introduces a whole other set of compromises in seating position,
weight distribution, traction on steep hills, etc. Long chain lines are
not necessarily a bad thing, as several issues with short chain lines go
away that make wide range gearing difficult.

--
Tom Sherman - Holstein-Friesland Bovinia
The weather is here, wish you were beautiful
 
J

Jon Bendtsen

Guest
Tom Sherman wrote:
> Jon Bendtsen wrote:
>> Tom Sherman wrote:
>>> TandemFan wrote:
>>>
>>> [cross-posted to ARBR for Perry Butler's amusement]
>>>
>>>> We have a R[ANS] Screamer tandem and there are a few idler rollers for
>>>> the chain. An outfit sells toothed idlers for about $250:
>>>> http://www.terracycle.com/Merchant2...oduct_Code=IdlRansScr&Category_Code=IdlersALL
>>>>
>>>>
>>>> They have a long blurb on why they are better:
>>>>
>>>> http://www.terracycle.com/Merchant2/merchant.mvc?Screen=CTGY&Store_Code=T&Category_Code=IdlersALL
>>>>
>>>>
>>>> What's the scoop? Does it make any difference at all, or are we going
>>>> to go faster?
>>>>
>>> Someone needs to tell Pat Franz that it is "RANS" and not "Rans".
>>>
>>> While the manufacturers in question are trying to meet a price point
>>> for their bicycles, they are not going to be putting junk chain
>>> idlers on their bicycles [1]. Therefore, while there is room for
>>> improvement, the gains will likely be small as drive-train friction
>>> is a small component of total non-conservative losses, even on a
>>> recumbent with a complicated chain-line.

>>
>> Why not avoid idlers and recumbents with complicated chain-lines?
>>
>> It might not (yet) be possible with a tandem, but for a single
>> rider bike, cruzbike offers a short normal chain-line.
>>

> And introduces a whole other set of compromises in seating position,


yeah, thats true.


> weight distribution, traction on steep hills, etc. Long chain lines are


actually i dont find the traction too bad up hill. But
we dont really have hills in Denmark, it's just flat flat
flat compared to other places.


> not necessarily a bad thing, as several issues with short chain lines go
> away that make wide range gearing difficult.


Why would short chainlines make wide range gearing difficult?
 
A

Adam Kadlubek

Guest
On 28 Kwi, 00:37, Jon Bendtsen <[email protected]> wrote:
> Tom Sherman wrote:
> > Jon Bendtsen wrote:
> >> Tom Sherman wrote:
> >>> TandemFan wrote:

>
> >>> [cross-posted to ARBR for Perry Butler's amusement]

>
> >>>> We have a R[ANS] Screamer tandem and there are a few idler rollers for
> >>>> the chain. An outfit sells toothed idlers for about $250:
> >>>>http://www.terracycle.com/Merchant2/merchant.mvc?Screen=PROD&Store_Co...

>
> >>>> They have a long blurb on why they are better:

>
> >>>>http://www.terracycle.com/Merchant2/merchant.mvc?Screen=CTGY&Store_Co...

>
> >>>> What's the scoop? Does it make any difference at all, or are we going
> >>>> to go faster?

>
> >>> Someone needs to tell Pat Franz that it is "RANS" and not "Rans".

>
> >>> While the manufacturers in question are trying to meet a price point
> >>> for their bicycles, they are not going to be putting junk chain
> >>> idlers on their bicycles [1]. Therefore, while there is room for
> >>> improvement, the gains will likely be small as drive-train friction
> >>> is a small component of total non-conservative losses, even on a
> >>> recumbent with a complicated chain-line.

>
> >> Why not avoid idlers and recumbents with complicated chain-lines?

>
> >> It might not (yet) be possible with a tandem, but for a single
> >> rider bike, cruzbike offers a short normal chain-line.

>
> > And introduces a whole other set of compromises in seating position,

>
> yeah, thats true.
>
> > weight distribution, traction on steep hills, etc. Long chain lines are

>
> actually i dont find the traction too bad up hill. But
> we dont really have hills in Denmark, it's just flat flat
> flat compared to other places.
>
> > not necessarily a bad thing, as several issues with short chain lines go
> > away that make wide range gearing difficult.

>
> Why would short chainlines make wide range gearing difficult?


Cross chain without guilt for instance.

--
Adam Kadlubek
 
J

Jon Bendtsen

Guest
Adam Kadlubek wrote:
> On 28 Kwi, 00:37, Jon Bendtsen <[email protected]> wrote:
>> Tom Sherman wrote:
>>> Jon Bendtsen wrote:
>>>> Tom Sherman wrote:
>>>>> TandemFan wrote:
>>>>> [cross-posted to ARBR for Perry Butler's amusement]
>>>>>> We have a R[ANS] Screamer tandem and there are a few idler rollers for
>>>>>> the chain. An outfit sells toothed idlers for about $250:
>>>>>> http://www.terracycle.com/Merchant2/merchant.mvc?Screen=PROD&Store_Co...
>>>>>> They have a long blurb on why they are better:
>>>>>> http://www.terracycle.com/Merchant2/merchant.mvc?Screen=CTGY&Store_Co...
>>>>>> What's the scoop? Does it make any difference at all, or are we going
>>>>>> to go faster?
>>>>> Someone needs to tell Pat Franz that it is "RANS" and not "Rans".
>>>>> While the manufacturers in question are trying to meet a price point
>>>>> for their bicycles, they are not going to be putting junk chain
>>>>> idlers on their bicycles [1]. Therefore, while there is room for
>>>>> improvement, the gains will likely be small as drive-train friction
>>>>> is a small component of total non-conservative losses, even on a
>>>>> recumbent with a complicated chain-line.
>>>> Why not avoid idlers and recumbents with complicated chain-lines?
>>>> It might not (yet) be possible with a tandem, but for a single
>>>> rider bike, cruzbike offers a short normal chain-line.
>>> And introduces a whole other set of compromises in seating position,

>> yeah, thats true.
>>
>>> weight distribution, traction on steep hills, etc. Long chain lines are

>> actually i dont find the traction too bad up hill. But
>> we dont really have hills in Denmark, it's just flat flat
>> flat compared to other places.
>>
>>> not necessarily a bad thing, as several issues with short chain lines go
>>> away that make wide range gearing difficult.

>> Why would short chainlines make wide range gearing difficult?

>
> Cross chain without guilt for instance.


Then combine a rohloff/nuvinci + a schlumpf drive == 0 cross chain.
If normal bikes can live with some cross chain, so can a recumbent.



JonB
 
[email protected] wrote:
> On Fri, 25 Apr 2008 06:06:14 -0400, TandemFan <[email protected]>
> wrote:
>
>> We have a Rans Screamer tandem and there are a few idler rollers for
>> the chain. An outfit sells toothed idlers for about $250:
>> http://www.terracycle.com/Merchant2...oduct_Code=IdlRansScr&Category_Code=IdlersALL
>>
>> They have a long blurb on why they are better:
>>
>> http://www.terracycle.com/Merchant2/merchant.mvc?Screen=CTGY&Store_Code=T&Category_Code=IdlersALL
>>
>> What's the scoop? Does it make any difference at all, or are we going
>> to go faster?
>>
>> Thanks!

>
> Dear TF,
>
> Note the absence of any figures to back up the claims of significant
> power losses.
>
> Cheers,
>
> Carl Fogel


test
 
T

Tom Sherman

Guest
Jon Bendtsen wrote:
> Tom Sherman wrote:
>> [...]
>> not necessarily a bad thing, as several issues with short chain lines
>> go away that make wide range gearing difficult.

>
> Why would short chainlines make wide range gearing difficult?


Proper alignment between front chain wheels and rear sprockets becomes
more critical with a shorter chain line, which makes things more
difficult when using non-standard components.

A long chain line in combination with a idler tensioner (e.g. Easy
Racers) or a mid-drive can allow for chain wheel and sprocket
combinations that would not work on a short chain line unless custom
derailers (sic) were used.

--
Tom Sherman - Holstein-Friesland Bovinia
The weather is here, wish you were beautiful
 
T

Tom Sherman

Guest
Jon Bendtsen wrote:
> Adam Kadlubek wrote:
>> On 28 Kwi, 00:37, Jon Bendtsen <[email protected]> wrote:
>>> Tom Sherman wrote:
>>>> Jon Bendtsen wrote:
>>>>> Tom Sherman wrote:
>>>>>> TandemFan wrote:
>>>>>> [cross-posted to ARBR for Perry Butler's amusement]
>>>>>>> We have a R[ANS] Screamer tandem and there are a few idler
>>>>>>> rollers for
>>>>>>> the chain. An outfit sells toothed idlers for about $250:
>>>>>>> http://www.terracycle.com/Merchant2/merchant.mvc?Screen=PROD&Store_Co...
>>>>>>>
>>>>>>> They have a long blurb on why they are better:
>>>>>>> http://www.terracycle.com/Merchant2/merchant.mvc?Screen=CTGY&Store_Co...
>>>>>>>
>>>>>>> What's the scoop? Does it make any difference at all, or are we
>>>>>>> going
>>>>>>> to go faster?
>>>>>> Someone needs to tell Pat Franz that it is "RANS" and not "Rans".
>>>>>> While the manufacturers in question are trying to meet a price point
>>>>>> for their bicycles, they are not going to be putting junk chain
>>>>>> idlers on their bicycles [1]. Therefore, while there is room for
>>>>>> improvement, the gains will likely be small as drive-train friction
>>>>>> is a small component of total non-conservative losses, even on a
>>>>>> recumbent with a complicated chain-line.
>>>>> Why not avoid idlers and recumbents with complicated chain-lines?
>>>>> It might not (yet) be possible with a tandem, but for a single
>>>>> rider bike, cruzbike offers a short normal chain-line.
>>>> And introduces a whole other set of compromises in seating position,
>>> yeah, thats true.
>>>
>>>> weight distribution, traction on steep hills, etc. Long chain lines are
>>> actually i dont find the traction too bad up hill. But
>>> we dont really have hills in Denmark, it's just flat flat
>>> flat compared to other places.
>>>
>>>> not necessarily a bad thing, as several issues with short chain
>>>> lines go
>>>> away that make wide range gearing difficult.
>>> Why would short chainlines make wide range gearing difficult?

>>
>> Cross chain without guilt for instance.

>
> Then combine a rohloff/nuvinci + a schlumpf drive == 0 cross chain.


No cross chain, but large expense. :(

> If normal bikes can live with some cross chain, so can a recumbent.
>

Cross-chaining becomes much less of an detriment with a long chain line.

--
Tom Sherman - Holstein-Friesland Bovinia
The weather is here, wish you were beautiful
 
The angle at which the chain enters and leaves front sprockets and
derailleur idlers is the sine of the angle which is the lateral offset
between the two ends of the chain span divided by the free span
length. Therefore, the longer the chainstays and the fewer the gears
on the sprocket cluster, the smaller the angle between chain and
sprocket plane. The angle causes lateral sprocket tooth wear and
idler wheel wear.

Jobst Brandt
 
T

Tom Sherman

Guest
[email protected] aka Jobst Brandt wrote:
> The angle at which the chain enters and leaves front sprockets and
> derailleur idlers is the sine of the angle which is the lateral offset
> between the two ends of the chain span divided by the free span
> length. Therefore, the longer the chainstays and the fewer the gears
> on the sprocket cluster, the smaller the angle between chain and
> sprocket plane. The angle causes lateral sprocket tooth wear and
> idler wheel wear.
>

Indeed, which is why I would not deliberately ride in cross chain gears
on my ATB with its 43 cm chain line (BB to hub) but will do so on my
RANS Rocket with its 131 cm chain line.

--
Tom Sherman - Holstein-Friesland Bovinia
The weather is here, wish you were beautiful
 
J

Jon Bendtsen

Guest
Tom Sherman wrote:
> Jon Bendtsen wrote:
>> Adam Kadlubek wrote:
>>> On 28 Kwi, 00:37, Jon Bendtsen <[email protected]> wrote:
>>>> Tom Sherman wrote:
>>>>> Jon Bendtsen wrote:
>>>>>> Tom Sherman wrote:
>>>>>>> TandemFan wrote:
>>>>>>> [cross-posted to ARBR for Perry Butler's amusement]


[cuuuut]

>>>>> not necessarily a bad thing, as several issues with short chain
>>>>> lines go
>>>>> away that make wide range gearing difficult.
>>>> Why would short chainlines make wide range gearing difficult?
>>>
>>> Cross chain without guilt for instance.

>>
>> Then combine a rohloff/nuvinci + a schlumpf drive == 0 cross chain.

>
> No cross chain, but large expense. :(


Yeah, rohloff is expensive. Nuvinci is not so bad, neither are the
schlumpf drive. Together they are, but you do get a VERY wide gear
range with no steps, it is all continuously variable. I dont think
i need more range than what the Nuvinci can give me, which is a little
wider than the 8 gear derailure i have now.


>> If normal bikes can live with some cross chain, so can a recumbent.
>>

> Cross-chaining becomes much less of an detriment with a long chain line.


You get other problems with a long chainline. If something hits it
trash or some plants.

But as you said above, it's a question about tradeoffs. I just dont
like long chainlines. And neither those tubes they run in.
 
J

Jon Bendtsen

Guest
Jon Bendtsen wrote:
> Tom Sherman wrote:
>> Jon Bendtsen wrote:
>>> Adam Kadlubek wrote:
>>>> On 28 Kwi, 00:37, Jon Bendtsen <[email protected]e.com> wrote:
>>>>> Tom Sherman wrote:
>>>>>> Jon Bendtsen wrote:
>>>>>>> Tom Sherman wrote:
>>>>>>>> TandemFan wrote:
>>>>>>>> [cross-posted to ARBR for Perry Butler's amusement]

>
> [cuuuut]
>
>>>>>> not necessarily a bad thing, as several issues with short chain
>>>>>> lines go
>>>>>> away that make wide range gearing difficult.
>>>>> Why would short chainlines make wide range gearing difficult?
>>>>
>>>> Cross chain without guilt for instance.
>>>
>>> Then combine a rohloff/nuvinci + a schlumpf drive == 0 cross chain.

>>
>> No cross chain, but large expense. :(

>
> Yeah, rohloff is expensive. Nuvinci is not so bad, neither are the
> schlumpf drive. Together they are, but you do get a VERY wide gear
> range with no steps, it is all continuously variable. I dont think
> i need more range than what the Nuvinci can give me, which is a little
> wider than the 8 gear derailure i have now.


i forgot to mention that i eventually want a Nuvinci, so i
might as well go for a bike that has a short chain line +
you can actually mount a child seat, i havent found others
that allowed that.



JonB
 
J

Jon

Guest
"Jon Bendtsen" <[email protected]> wrote
> You get other problems with a long chainline. If something hits it
> trash or some plants.


Most likely places of plant interaction with chain line seem
independent of chain length, e.i., at chain rings, derailuers,
idlers... And some recumbent designs with higher bottom
brackets raise chain overall.

> But as you said above, it's a question about tradeoffs. I just dont
> like long chainlines. And neither those tubes they run in.


Fine, but don't presume that all long chain lines have tubes.
For instance, the Easy Racers LWB bikes have chains
about 2.3 times longer than "normal" but have no tubes.

Jon