531Aussie

The 'general purpose' fabric/plastic glue (I dunno what brands are popular in The States) from the supermarket is handy, coz it can be undone with a strong grip, or with some small pliers. It's a little annoying to use, because it can get messy, and coz you've gotta let it half-dry for a "while" before it works.

Fox Farm

I ride a Sella Italia Flite Max Flow and find it to be very good on long rides. Actually have them on both road bikes. I have used Concor, Avocet, and a few others that I can't remember any more and find that the cut out does provide a pressure relief in a sensitive area for long rides, FOR ME.

WhyFi

Considering the fact that I was once a 15-year-old boy, I find it laughable that others think they know my junk better than I do.

Garfield Cat

The SLR is sensitive to positioning of the rider. If you tend to slide fore and aft during a ride, that inner thigh will feel it. Also lower the seat just a little to see if that helps. The Fizik Arione doesn't have that problem. But it doesn't have the cut out either.

chaadster

Maybe less junk just needs less space, while bigger junk needs more space?

thump55

When I started riding, I went to the bike shop. I put my bike on a trainer. I tried 11 saddles (12 if you want to count my stock saddle).

9 of them did not have a cut-out, 3 of them did.

The two best saddles for me had cut-outs. The five worst saddles did not have cut-outs.

Those are pretty convincing numbers that a cut-out can make a lot of difference.

DaveWC

I completely agree with this post. I love the SLR Superflow but not on my rollers.

ultraman6970

The only saddle i would love to see with a cut out is kontact. Been looking for a busted one for a while just to carve a channel in the middle. Awesome saddle but needs a carving or a cut out imo.

merlinextraligh

As to the supposed to part, that would according to urologists, and anyone who want to keep their private parts functioning. Prolonged pressure there is not going to be good for you.

BTW, the reason a cut out saddle is working for you is because you are sitting on your sitz bones with it, not on your perineum. So you're actually making my point that your weight on the saddle is supposed to be carried by your sitzbones.

There's nothing wrong with using a saddle with a cutout if it works for you. The point is however, it's not the cutout that's making it work, it's that it's properly designed, and fit for you.

WhyFi

And yet there are people that can sit on a firm, perfectly flat surface, weight on their sit bones, and still suffer from circulation issues due to soft tissue compression. For these people, a cutout or relief channel are necessary. Why is it hard to fathom that personal anatomy is personal?

Fox Farm

/\ /\ exactly!

merlinextraligh

If a cut out saddle works for you great. I just think that in most cases, whether the saddle has a cutout or not, is not as important as whether the saddle fits.

Without reading all this, it appears the OP didn't make an uncomfortable saddle comfortable by putting a cutout in it.

Thus my point in all this is that cutout, or no cutout may not be the best criteria upon which to select a saddle.

Beyond that use you what you want.

rdtindsm

Each spoke has an aerodynamic cost drag_per_spoke. Total drag should be roughly no._spokes * drag_per_spoke. There may be secondary effects such as the drafting effect and the vortex created by the spinning wheel that could prove me wrong. Of course, we may find that we needed to account for these effects if we so wind tunnel testing.

I only have an engineering education although a certain amount of science is involved. Not a huge difference in drag, but it's there and would be important in an elite competitive arena. I've podiumed in the masters national tt and part of the preparation was buying a low spoke count front wheel. I'm not convinced the money was entirely ill spent. Part of the process is noting empirical evidence to guide more rigorous analysis.

Science requires a certain amount of analysis and doesn't have much room for those who merely assert their authority as a scientist. Aristotle did that and ruined the field for a goodly number of years.

rdtindsm

That was easy. Each spoke has an aerodynamic cost drag_per_spoke. Total drag should be roughly no._spokes * drag_per_spoke. There may be secondary effects such as the drafting effect and the vortex created by the spinning wheel that could prove me wrong. Of course, we may find that we needed to account for these effects if we do wind tunnel testing.

I only have an engineering education although a certain amount of science is involved. The thought processes should be similar, with the engineering emphasis being on application. Not a huge difference in drag, but it's there and would be important in an elite competitive arena. I've podiumed in the masters national tt and part of the preparation was buying a low spoke count front wheel. I'm not convinced the money was entirely ill spent.

Part of the process is noting empirical evidence to guide more rigorous analysis or simply to use based on experince. Science requires a certain amount of analysis and doesn't have much room for those who merely assert their authority as a scientist. Aristotle did that and ruined the field for a goodly number of years.

furballi

If the benefit amounts to more than a few watt, then low-count wheel manufacturers would have wind tunnel data touting the benefit. A cheap but easy real world test is to hook up a small gasoline motor to the bike and test indoor. The top speed achieved with 36H and 32H wheels will probably fall well within the noise range of this experiment. The air drag caused by an additional 12 rotating spokes at 250 rpm is mininal and does not result in an improvement of top speed.

One can also perform an indoor coast-down test from 20 mph to 15 mph, with the only variable being the spoke count. And again, the data will fall well withing the noise range of the experiment.

Why not provide measured numbers and equations that can withstand the scrutiny of the engineering community and support your claim? There are many other variables such as mass of rider and frontal cross section area that overwhelm any minute amount of aero gain from reducing spoke count.

hyhuu

This is my reason for preferring a cutout sadle in the summer but I switch to a regular one during winter. Fit wise, I'm easy. I can fit on just about any saddle that is narrow.

chaadster

Going from 32 round spokes to 20 bladed spokes will save significant watts to keep at speed, though, and it's often the case that low spoke count wheels employ aero spokes, which are more important to the savings than just the fewer number of spokes, which you are correct in saying may not provide any measurable savings at all (everything else being equal). Zipp published this study: https://docs.google.com/viewer?a=v&q...0Vl5mc3CDjXuGg

chaadster

I should probably do the same! Around freezing, and certainly below, my SMP is very cold on the crotch, even with tights over padded shorts. It's a notable sensation, being cold from literally the bottom up!

Commodus

Some folks like to buy saddles. I know a few, you meet all kinds of characters around the racing and long-distance crowds. These guys, they tend to be the same ones who refuse to pay for a fitting session, and instead chase around after the perfect saddle, as if their arse exists in isolation from the rest of their body, and from the bike. I even saw a guy who tried ten saddles in a row one time, all the while refusing to change even setback or saddle height. He left convinced a cut-out is necessary. Okay.

I think it's kind of a side hobby, like weight-weeniesm.

furballi

Quote from the manufacturer that's trying to sell expensive wheels:

"the 4 spoke differences between wheels are largely within the margin of error of the wind tunnel itself".

Instead of relying on wind tunnel data, which can be highly unreliable at detecting small changes, a more accurate method is to record the actual DC motor's input voltage and current (VA) needed to spin a wheel at a set rpm. One can use the same rim drilled for 20H, 24H, 32H, and 36H to obtain the actual power (DC motor) sent to the motor. I would be surprised to see a deviation of +/- 3 watts at 250 rpm.

Gran Fondo

Correct. I made an uncomfortable saddle into an uncomfortable saddle with a cutout. I tested on a saddle I won't ever use because it is uncomfortable. The idea was to see if I could do it. If successful, I would do it to the saddle that I DO find comfortable. Not because the cutout will make it more comfotable, but because it will give an already known comfortable saddle the benefits that a cutout provides. I can't beleive this thread has turned into one about the aerodynamics of spoke counts. Reminds me of the old classroom experiment where the teacher wispers a story to the kid in the front of the classroom. Then each kid reiterates it secretly to the next, and the last one to hear it retells it aloud to see how different the story transpired.

Gran Fondo

I tried to PM you, but couldn't because I don't have 50 posts yet. This forum has a ton of stupid rules. Email me privately at blacktopracing @ zoominternet.net (remove spaces).

I'll do it. Don't be shocked if it looks worse in person than in the pictures, but it does work.

rearviewbeer

My junk went numb on longer rides without a cutout, got a Brooks Imperial, no numbness. Bought new bike recently, tried new saddle w/out cutout, Brooks went on that bike next day. Break in did not take long, maybe 150 miles, and was never uncomfortable.

I think point of all this is that what works for one person may not for another and vice versa...

531Aussie

Yeah, and this, which has stuck with me ever since I read a long time ago:
"Once these major improvements have been made, small changes in spoke shape or count are marginal at best. In the 404 test, we see that adding 12 additional spokes leaves us a possible increase in wattage of only 1-5 watts"

I interpret this as: once the rim is the 'right' depth and shape, and the spokes are a good-enough shape, adding lots of spokes to a rim that's ~60mm or deeper, makes very little difference.

In light of this, it annoys me that Zipp no longer sell the Clydesdale versions (right?). Eh, whatever.....

Holy off topic, Batman

furballi

I spent years in the aerospace industry debunking myths. We have a cost-plus program, so there are always people with "charge accounts" trying to re-invent the wheel. Wind-tunnel testing is a combination of art and science. For a rotating mass like a bicycle wheel, any minute benefit seen in the lab would be wiped out by real-world influences such as wind, temperature, and humidity. Air is a compressible fluid. Change in temperature, pressure, and humidity will have a dramatic influence on the V and a vectors.