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#16 |
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On May 9, 10:44*pm, Ron Ruff <rruffrr...@yahoo.com> wrote:
> On May 9, 10:14*am, "joseph.santanie...@gmail.com" > > <joseph.santanie...@gmail.com> wrote: > > There is some interesting stuff here: > > >http://www.geocities.com/spokeanwheel/lacingsr.htm > > It sure is interesting, but don't believe most of what you read on > that site... > > > My main concern is lateral stiffness in the front, and lateral > > stiffnes and torque resistance in the rear. I don't want the brakes to > > rub when I am out of the saddle, and I certainly don't want the > > occasional "boing" feeling I get with the rear wheel on my lightweight > > wheels when I stand in *high torque conditions. > > Your light wheels have a narrow flange spacing and a light rim... this > won't be the case with your aero wheels. > > > So radial in the front sounds like the way to go for stiffness. Heads > > in. Pretty straight forward. > > Do you have 28 spokes in the front too? If so, you can lace it any way > you want... it will be stiffer than the rear anyway. > > > What do you guys think about the 2x NDS, 3x DS recommended in the link > > above? And the reasoning? > > That should be ok... but I'm not sure it is ideal. I think Dave said > it well in the post above. If you have a torsionally stiff hub, then > the NDS will be involved in torque transfer if it is cross-laced. This > is good in that it reduces the amount that the DS needs to transfer... > but bad in that the NDS spokes are more likely to go slack from > combined torque, radial, and lateral loads. The trick is figuring out > if NDS spokes going slack is more likely to be an issue than DS spokes > getting overloaded by torque. Unless you are sprinting up steep hills > *in a low gear* the torque isn't going to be a problem with only half > the spokes crossed. So... I still think radial on the NDS would be my > choice. The worst hills I'm worried about are probably 10-14% and short enough to be stomped in 53x19 or 17 so. This will involve standing of course, and probably a fair amount of thrashing side to side. So lateral stiffness could be an issue. So to make sure I underatand the reasoning: radial up front to be as stiff laterally as possible, and 2x DS rear to provide torque transfer, radial NDS (heads in) to provide lateral stiffness. Correct? Joseph |
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#17 | |
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Registered User
Join Date: Sep 2003
Location: Suburban Chicago
Posts: 2,778
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Quote:
sounds correct to me. |
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#18 |
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On May 9, 3:32*pm, "joseph.santanie...@gmail.com"
<joseph.santanie...@gmail.com> wrote: > So to make sure I underatand the reasoning: radial up front to be as > stiff laterally as possible, and 2x DS rear to provide torque > transfer, radial NDS (heads in) to provide lateral stiffness. Correct? Good enough. You could lace the DS 3x... but make sure you check the angle the spokes make at the rim in any case. I bend the spokes above the threads a little so that the nipples are more in line with the holes. I don't know what rim you are using... some are more sensitive to this than others. You want to avoid having bending loads at that point, which would stress both the spoke threads and the rim. |
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#19 |
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On May 10, 6:45*am, Ron Ruff <rruffrr...@yahoo.com> wrote:
> On May 9, 3:32*pm, "joseph.santanie...@gmail.com" > > <joseph.santanie...@gmail.com> wrote: > > So to make sure I underatand the reasoning: radial up front to be as > > stiff laterally as possible, and 2x DS rear to provide torque > > transfer, radial NDS (heads in) to provide lateral stiffness. Correct? > > Good enough. You could lace the DS 3x... but make sure you check the > angle the spokes make at the rim in any case. I bend the spokes above > the threads a little so that the nipples are more in line with the > holes. I don't know what rim you are using... some are more sensitive > to this than others. You want to avoid having bending loads at that > point, which would stress both the spoke threads and the rim. Gigantex internal nipple rims. Joseph |
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#20 |
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On May 9, 10:44*pm, Ron Ruff <rruffrr...@yahoo.com> wrote:
> On May 9, 10:14*am, "joseph.santanie...@gmail.com" > > <joseph.santanie...@gmail.com> wrote: > > There is some interesting stuff here: > > >http://www.geocities.com/spokeanwheel/lacingsr.htm > > It sure is interesting, but don't believe most of what you read on > that site... > > > My main concern is lateral stiffness in the front, and lateral > > stiffnes and torque resistance in the rear. I don't want the brakes to > > rub when I am out of the saddle, and I certainly don't want the > > occasional "boing" feeling I get with the rear wheel on my lightweight > > wheels when I stand in *high torque conditions. > > Your light wheels have a narrow flange spacing and a light rim... this > won't be the case with your aero wheels. > > > So radial in the front sounds like the way to go for stiffness. Heads > > in. Pretty straight forward. > > Do you have 28 spokes in the front too? If so, you can lace it any way > you want... it will be stiffer than the rear anyway. > > > What do you guys think about the 2x NDS, 3x DS recommended in the link > > above? And the reasoning? > > That should be ok... but I'm not sure it is ideal. I think Dave said > it well in the post above. If you have a torsionally stiff hub, then > the NDS will be involved in torque transfer if it is cross-laced. This > is good in that it reduces the amount that the DS needs to transfer... > but bad in that the NDS spokes are more likely to go slack from > combined torque, radial, and lateral loads. The trick is figuring out > if NDS spokes going slack is more likely to be an issue than DS spokes > getting overloaded by torque. Unless you are sprinting up steep hills > *in a low gear* the torque isn't going to be a problem with only half > the spokes crossed. So... I still think radial on the NDS would be my > choice. Looking at my shiny new 7800 rear hub, I can't imagine it is anything but torsionally stiff. Any flex it would show under load would have to be microscopic. If that is the case, it doesn't matter which side the spokes are on. Any "pull" spoke transfers torque to the rim, whichever side it is on. So then it would make sense to have radial on the DS, not the NDS. That way the shorter spoke and resulting angle helps make up for the more inboard placement of the DS flange. This is totally unscientific and anecdotal, but I just took my light wheels (28h, 2x DS, radial NDS, narrow AC hub flanges) for a short test, and did some purposefully agressive side to side sprints. It seems the wheel only have the occasional flop when I lean the bike to the right, and the rims feels like it flexes in toward the NDS. The flanges mean there is essentially no dish, so the only real difference between each side is spoke length and thus angle. The rim does not seem to flop toward the DS. That makes sense because the NDS is radial and is in better position to resist. Joseph |
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#21 |
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On May 10, 6:36*am, "joseph.santanie...@gmail.com"
<joseph.santanie...@gmail.com> wrote: > If that is the case, it doesn't matter which side the spokes are on. > Any "pull" spoke transfers torque to the rim, whichever side it is on. > So then it would make sense to have radial on the DS, not the NDS. > That way the shorter spoke and resulting angle helps make up for the > more inboard placement of the DS flange. It would help a little... but think about what you've done to the NDS spokes. Instead of 19mm and 36mm spacing, you'd get maybe 21mm and 36mm (just guessing). If you put 120kg in the DS, then the NDS would be 70kg... and these are the only spokes transfering torque. Combine a high torque load with the radial and side loads, and it won't take much to make the pushing spokes go slack. > This is totally unscientific and anecdotal, but I just took my light > wheels (28h, 2x DS, radial NDS, narrow AC hub flanges) for a short > test, and did some purposefully agressive side to side sprints. It > seems the wheel only have the occasional flop when I lean the bike to > the right, and the rims feels like it flexes in toward the NDS. You are very perceptive! This is the side that will buckle first, since the NDS tension is lower and the spokes are at more of an angle. You can demonstrate this easily by taking the wheel out and pressing on the edges of the rim, while the axle rests on a solid surface. The wheel will "boing" with lower force when you press towards the NDS. > The > flanges mean there is essentially no dish, so the only real difference > between each side is spoke length and thus angle. The rim does not > seem to flop toward the DS. That makes sense because the NDS is radial > and is in better position to resist. There is dish. Probably ~19mm DS and 28mm NDS. This is the main difference. Oddly, if the spacing (dish) was greater, you'd think the lateral stability situation would get worse... but it actually improves. A narrow spacing improves the tension balance, but this is only an issue if you have spokes going slack from radial loads... for all other loads it makes things worse. Narrow flanges reduce the lateral stiffness a lot, since this goes up exponentially with bracing angle, and they also reduce the load required to make the wheel buckle. |
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#22 |
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Ron Ruff wrote:
> On May 10, 6:36�am, "joseph.santanie...@gmail.com" > <joseph.santanie...@gmail.com> wrote: >> If that is the case, it doesn't matter which side the spokes are on. >> Any "pull" spoke transfers torque to the rim, whichever side it is on. >> So then it would make sense to have radial on the DS, not the NDS. >> That way the shorter spoke and resulting angle helps make up for the >> more inboard placement of the DS flange. > > It would help a little... but think about what you've done to the NDS > spokes. Instead of 19mm and 36mm spacing, you'd get maybe 21mm and > 36mm (just guessing). If you put 120kg in the DS, then the NDS would > be 70kg... and these are the only spokes transfering torque. Combine a > high torque load with the radial and side loads, and it won't take > much to make the pushing spokes go slack. > >> This is totally unscientific and anecdotal, but I just took my light >> wheels (28h, 2x DS, radial NDS, narrow AC hub flanges) for a short >> test, and did some purposefully agressive side to side sprints. It >> seems the wheel only have the occasional flop when I lean the bike to >> the right, and the rims feels like it flexes in toward the NDS. > > You are very perceptive! This is the side that will buckle first, > since the NDS tension is lower and the spokes are at more of an angle. it's not so much a tension thing as a spoke angle thing. and it's the angle of the /drive side/ spokes that causes it. basically, the closer the drive side spoke angle is to perpendicular, the more any applied load stretches those spokes, hence the non-drive side can slack more easily. > You can demonstrate this easily by taking the wheel out and pressing > on the edges of the rim, while the axle rests on a solid surface. The > wheel will "boing" with lower force when you press towards the NDS. indeed. see above. > >> The >> flanges mean there is essentially no dish, so the only real difference >> between each side is spoke length and thus angle. The rim does not >> seem to flop toward the DS. That makes sense because the NDS is radial >> and is in better position to resist. > > There is dish. Probably ~19mm DS and 28mm NDS. This is the main > difference. Oddly, if the spacing (dish) was greater, you'd think the > lateral stability situation would get worse... but it actually > improves. A narrow spacing improves the tension balance, but this is > only an issue if you have spokes going slack from radial loads... for > all other loads it makes things worse. Narrow flanges reduce the > lateral stiffness a lot, since this goes up exponentially with bracing > angle, and they also reduce the load required to make the wheel > buckle. |
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#23 | |
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Registered User
Join Date: Sep 2003
Location: Suburban Chicago
Posts: 2,778
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Quote:
I agree with Ron Ruff. Whatever way you finally decide to build them, make sure to stabilize the build and check spoke tensions often for at least the first 100 miles to make sure that everything stays where you put them... or at least gets back there. I don't see any benefit for 3X on a 28 spoke wheel. The wider set flanges and thicker hub mid section of the 7800 Dura Ace hubs make them stiffer in all dimensions. Your 50 mm high rims also help stiffness in three ways: the rims themselves due to the rim height the spoke support angle is greater the spoke length is shorter Each contribution may be small, but it is measurable and in the direction of increased stiffness. |
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#24 |
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On May 10, 4:36*pm, Ron Ruff <rruffrr...@yahoo.com> wrote:
> On May 10, 6:36*am, "joseph.santanie...@gmail.com" > > <joseph.santanie...@gmail.com> wrote: > > If that is the case, it doesn't matter which side the spokes are on. > > Any "pull" spoke transfers torque to the rim, whichever side it is on. > > So then it would make sense to have radial on the DS, not the NDS. > > That way the shorter spoke and resulting angle helps make up for the > > more inboard placement of the DS flange. > > It would help a little... but think about what you've done to the NDS > spokes. Instead of 19mm and 36mm spacing, you'd get maybe 21mm and > 36mm (just guessing). If you put 120kg in the DS, then the NDS would > be 70kg... and these are the only spokes transfering torque. Combine a > high torque load with the radial and side loads, and it won't take > much to make the pushing spokes go slack. I see. Radial DS would make the wheel more laterally stiff, but this would come at the unacceptable expense of NDS push spokes going slack under high torque loads and probably boinging the wheel. > > > This is totally unscientific and anecdotal, but I just took my light > > wheels (28h, 2x DS, radial NDS, narrow AC hub flanges) for a short > > test, and did some purposefully agressive side to side sprints. It > > seems the wheel only have the occasional flop when I lean the bike to > > the right, and the rims feels like it flexes in toward the NDS. > > You are very perceptive! This is the side that will buckle first, > since the NDS tension is lower and the spokes are at more of an angle. > You can demonstrate this easily by taking the wheel out and pressing > on the edges of the rim, while the axle rests on a solid surface. The > wheel will "boing" with lower force when you press towards the NDS. > > > The > > flanges mean there is essentially no dish, so the only real difference > > between each side is spoke length and thus angle. The rim does not > > seem to flop toward the DS. That makes sense because the NDS is radial > > and is in better position to resist. > > There is dish. Probably ~19mm DS and 28mm NDS. This is the main > difference. Oddly, if the spacing (dish) was greater, you'd think the > lateral stability situation would get worse... but it actually > improves. A narrow spacing improves the tension balance, but this is > only an issue if you have spokes going slack from radial loads... for > all other loads it makes things worse. Narrow flanges reduce the > lateral stiffness a lot, since this goes up exponentially with bracing > angle, and they also reduce the load required to make the wheel > buckle. I guess that in general the wider flange spacing of the DA hubs (yet smaller diameter) than the AC hubs (38mm, 22mm vs 31mm, 17mm) is what is going to make the biggest difference. So radial NDS, 2x DS. But what about my light wheels that buckle? Should I rebuild those 2x both sides? Joseph |
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#25 |
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joseph.santaniello@gmail.com wrote:
> On May 10, 4:36�pm, Ron Ruff <rruffrr...@yahoo.com> wrote: >> On May 10, 6:36�am, "joseph.santanie...@gmail.com" >> >> <joseph.santanie...@gmail.com> wrote: >>> If that is the case, it doesn't matter which side the spokes are on. >>> Any "pull" spoke transfers torque to the rim, whichever side it is on. >>> So then it would make sense to have radial on the DS, not the NDS. >>> That way the shorter spoke and resulting angle helps make up for the >>> more inboard placement of the DS flange. >> It would help a little... but think about what you've done to the NDS >> spokes. Instead of 19mm and 36mm spacing, you'd get maybe 21mm and >> 36mm (just guessing). If you put 120kg in the DS, then the NDS would >> be 70kg... and these are the only spokes transfering torque. Combine a >> high torque load with the radial and side loads, and it won't take >> much to make the pushing spokes go slack. > > I see. Radial DS would make the wheel more laterally stiff, um, well, it's not so much the radial configuration, it's more the effective flange spacing. > but this > would come at the unacceptable expense of NDS push spokes going slack > under high torque loads and probably boinging the wheel. again, not so much torque, more lateral loading. > >>> This is totally unscientific and anecdotal, but I just took my light >>> wheels (28h, 2x DS, radial NDS, narrow AC hub flanges) for a short >>> test, and did some purposefully agressive side to side sprints. It >>> seems the wheel only have the occasional flop when I lean the bike to >>> the right, and the rims feels like it flexes in toward the NDS. >> You are very perceptive! This is the side that will buckle first, >> since the NDS tension is lower and the spokes are at more of an angle. >> You can demonstrate this easily by taking the wheel out and pressing >> on the edges of the rim, while the axle rests on a solid surface. The >> wheel will "boing" with lower force when you press towards the NDS. >> >>> The >>> flanges mean there is essentially no dish, so the only real difference >>> between each side is spoke length and thus angle. The rim does not >>> seem to flop toward the DS. That makes sense because the NDS is radial >>> and is in better position to resist. >> There is dish. Probably ~19mm DS and 28mm NDS. This is the main >> difference. Oddly, if the spacing (dish) was greater, you'd think the >> lateral stability situation would get worse... but it actually >> improves. A narrow spacing improves the tension balance, but this is >> only an issue if you have spokes going slack from radial loads... for >> all other loads it makes things worse. Narrow flanges reduce the >> lateral stiffness a lot, since this goes up exponentially with bracing >> angle, and they also reduce the load required to make the wheel >> buckle. > > I guess that in general the wider flange spacing of the DA hubs (yet > smaller diameter) than the AC hubs (38mm, 22mm vs 31mm, 17mm) is what > is going to make the biggest difference. So radial NDS, 2x DS. > > But what about my light wheels that buckle? Should I rebuild those 2x > both sides? they have american classics? try rebuilding using a hub with a wider flange spacing. shimano are the best for this. |
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#26 |
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On May 10, 9:28*am, "joseph.santanie...@gmail.com"
<joseph.santanie...@gmail.com> wrote: > But what about my light wheels that buckle? Should I rebuild those 2x > both sides? Are they laced heads-in now on the NDS? If not, try that. If they are heads-in, then heavier spokes are the only thing that will help... but I'd probably just sell them to a lighter rider before trying that. |
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#27 |
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On May 10, 7:29*pm, Ron Ruff <rruffrr...@yahoo.com> wrote:
> On May 10, 9:28*am, "joseph.santanie...@gmail.com" > > <joseph.santanie...@gmail.com> wrote: > > But what about my light wheels that buckle? Should I rebuild those 2x > > both sides? > > Are they laced heads-in now on the NDS? If not, try that. If they are > heads-in, then heavier spokes are the only thing that will help... but > I'd probably just sell them to a lighter rider before trying that. All my lighter buddies are afraid of tubulars, and even more vain than me! The old-school Mavic OR10 rims just look funny to them. Not too mention the insanley high spoke count! They do however do a double take when I hand them a wheel to feel it's (lack of) weight. And then when they find out how much they cost (1/2 their heavier pre-builts) they give me a blank stare. They are heads out now. I'll flip them. If I go with beefier spokes, should I replace them all, or just NDS? Joseph |
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#28 | |
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Registered User
Join Date: Sep 2003
Location: Suburban Chicago
Posts: 2,778
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Quote:
Are you set on retaining those rims in combination with the narrow spaced hubs? You can add ~20% stiffness with beefier spokes and heads in orientation of spokes, but at your weight and power I wonder if it is worth the effort and costs. Light weight wheels are fun to show off, but they don't make much difference to the overall weight of rider + bicycle ... especially as the rider weight contribution is over 80%. I would move ahead with the wheels you are working on now so you can see what they ride like. Ron Ruff's idea of selling your light weight rider who thinks tubies are better (or at least worth it). There are a small percentage of riders who have a positive bias for tubulars... and some like the old style Mavic OR rims too. |
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#29 |
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On May 10, 8:17*pm, daveornee <daveornee.397...@no-
mx.forums.cyclingforums.com> wrote: > joseph.santanie...@gmail.com Wrote: > > > On May 10, 7:29*pm, Ron Ruff <rruffrr...@yahoo.com> wrote: > > > On May 10, 9:28*am, "joseph.santanie...@gmail.com" > > > > <joseph.santanie...@gmail.com> wrote: > > > > But what about my light wheels that buckle? Should I rebuild those > > 2x > > > > both sides? > > > > Are they laced heads-in now on the NDS? If not, try that. If they > > are > > > heads-in, then heavier spokes are the only thing that will help... > > but > > > I'd probably just sell them to a lighter rider before trying that. > > > All my lighter buddies are afraid of tubulars, and even more vain than > > me! The old-school Mavic OR10 rims just look funny to them. Not too > > mention the insanley high spoke count! They do however do a double > > take when I hand them a wheel to feel it's (lack of) weight. And then > > when they find out how much they cost (1/2 their heavier pre-builts) > > they give me a blank stare. > > > They are heads out now. I'll flip them. If I go with beefier spokes, > > should I replace them all, or just NDS? > > > Joseph > > Are you set on retaining those rims in combination with the narrow > spaced hubs? > You can add ~20% stiffness with beefier spokes and heads in orientation > of spokes, but at your weight and power I wonder if it is worth the > effort and costs. * Light weight wheels are fun to show off, but they > don't make much difference to the overall weight of rider + bicycle ... > especially as the rider weight contribution is over 80%. > I would move ahead with the wheels you are working on now so you can > see what they ride like. > Ron Ruff's idea of selling your light weight rider who thinks tubies > are better (or at least worth it). * *There are a small percentage of > riders who have a positive bias for tubulars... and some like the old > style Mavic OR rims too. > > -- > daveornee I'm not set on keeping them, but nobody I know is interested in buying, even for cheap. Fixing them is a low priority. I'll try flipping the spokes first (free) and maybe some heavier spokes if I happen across any suitable. If these new aero wheels (Gigantex/Dura Ace) are nice, I may buy some more of those rims and use the AC hubs and those I could sell. Then I'll keep the OR10's for some future unknown project. Joseph |
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#30 |
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On May 10, 11:39*am, "joseph.santanie...@gmail.com"
<joseph.santanie...@gmail.com> wrote: > They are heads out now. I'll flip them. If I go with beefier spokes, > should I replace them all, or just NDS? Just flipping them might help enough. If you replace the spokes with heavier ones, I'd do them all. What size do you have now? If they are 2.0/1.8, then they are already as heavy as you'd want to go. |
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