Jarrett2

So, last night I am about to leave to ride on my weekly night ride. It's the same route each week. I walk out into the garage to find my front tire is flat. Since I'm pressed for time, I just switched to my backup front wheel (which is the stock front wheel), aired it up and went for the ride.

During the ride, I was noticing my hands were really feeling the road and getting beat up. Having to shake them out, which I never have to do these days. I remembered feeling this way when I first got the bike, but stopped noticing it after getting some after market wheels.

The stock wheel I used last night:

Fulcrum Racing 5 rim
16 spokes, 2.0mm (DT Comp maybe), radial laced
Specialized Espoir 25mm @ 120 psi

My regular wheel:

DT Swiss RR440 rim
32 spokes, DT Revolution 2.0/1.5/2.0, 3 cross laced
Gatorskin 25mm @ 120 psi

I read on the Sheldon Brown site that many people feel like a 16 spoke/radial laced wheel is more harsh than a 32 spoke/3 cross wheel, but that is apparently debunked by Jobst Brandt.

So if there was no difference, why was the front end ride last night so much more harsh than it usually is?

fietsbob

Un detectable in reality while riding because a tensioned spoked wheel acts like a whole , the main difference you may perceive

is your tire choice.

But, remember there was an old story (Danish writer) about the Princess and a Pea... The Princess and the Pea - Wikipedia, the free encyclopedia

hueyhoolihan

probably a combination of tire and PSI.

Jarrett2

So with both tires at 120 psi, the Specialized Espoir is just that much more harsh that a Gatorskin?

fietsbob

Its the Air pressure you put in it. that 120 psi... want a softer ride Go to a Bike that takes a wider Tire .. and so operates at a lower Psi.

SquidPuppet

Swap the tires and see if you notice a difference.

HillRider

I have a Shimano WH-R560 prebuilt front wheel on one bike:

Shimano provided hub
Shimano 24 mm deep rim.
16 straight pull, 2 mm bladed spokes, radial laced.
700-23 Vittoria Rubino Slick tire @ 105 psi

I have a Colorado Cyclist provided wheel on another, similar bike:

Campy Chorus hub
Mavic CXP-33 24 mm deep rim
32 spokes DT 2.0/1.8/2.0 db, laced 3X
700-23 Vittoria Rubino Pro @105 psi

If I couldn't see these wheels I could not tell the difference between them while riding if you paid me. Perhaps, as fietsbob said, it is the tires or the route you took.

Jarrett2

Same route, same PSI.

So it is the tires, that's what everyone is going with?

Bill Kapaun

I find day to day variation on the same bike.
I figure it's just me doing something slightly different or feeling slightly different. (some days the joints hurt more than others)

HillRider

Gatorskins are notoriously stiff as a result of the extra puncture resistant layers in the casing. Perhaps that's the difference. The Vittoria Rubino Pro's I mentioned are quite supple but have decent flat resistance.

Drew Eckhardt 

Tires (carcass flexibility varies in both the tread and side walls) and placebo effect.

FWIW, if you don't weigh 300 pounds you'll be much happier with less pressure in the tires. At 215 pounds I started each week at 90-95 psi front 100-105 rear and was down to 80-85 and 90-95 respectively five days later without any pinch flats.

Jarrett2

Meaning a stiffer tire is more comfortable?

Drew Eckhardt 

No. In this case the Gatorskins are lighter and more supple.

To quote Specialized

"The Espoir is an extremely reliable road tire, ideal for ambitious training and high-mileage rides. This finely-crafted tire is designed for ultimate reliability and durability."

where reliability and durability mean sacrificing ride quality and rolling resistance.

It has two flat protection belts.

With all the rubber and extras the 25mm width weighs 370g.

Gatorskins are durable puncture-resistant tires that ride relatively well in spite of that.

The 25mm size with wire beads weighs 300g which is 70g less than the Specialized. For comparison purposes, that difference is more than the cooked patties in a Big Mac (total 90g raw, will loose 1/3 of that when cooked). Obviously that makes it more supple and better riding.

The folding 25mm Gatorskin is 250g and although swapping steel beads for kevlar does not affect ride, it allows comparison to performance oriented road tires that only come with folding beads.

The Continental GP4000S is a nice riding tire that's surprisingly durable (I'm aware of peoples' sidewall damage issues). It tips the scales at 230g in the 25mm width - 20g less carcass than the Gatorskin.

Jarrett2

So the lighter, less material Gatorskin is what is making the difference in comfort? I'm surprised that the Gatorskin is lighter as I've found it to be way more puncture resistant than the Espoir.

Earl Grey

Bit late, but Brandt's argument (convincing IMO) is that deflection due to spoke elasticity / pattern / length is totally swamped by the deflection of the tire and the structure between hub and contact points. Brandt's book contains some complex math calculating the stiffness of the wheel alone to support the argument.

dsaul

I agree with Drew. 120psi in a front wheel sounds painful to me unless you are very heavy. The front wheel doesn't carry the same load as the rear , so there is no reason to run the same pressure in both.

Jarrett2

I'm around 275 right now. What PSI would you suggest in the front tire?

I've been told by all my LBS's to run 120 in both tires due to my size.

fietsbob

what is the range imprinted on the side of the tire Casing? 120 maybe in a Premium 23 .. is on the edge of trouble with a $20 tire ..

but you can buy a wider tire , still premium , and the bigger Volume will let it operate at a bit Lower Pressure


they saw you and what tire they saw on your Bike In Front of them .

FBinNY 

Not saying it can be felt, or that you either felt it or didn't, but there is a difference in "harshness" between radial and most crossed patterns.

It relates not to the number of crosses, just that there are some and that the spokes are woven over/under. That makes each spoke take a slight detour on the way from hum to rim, and allows load transfer from one to the other, as the spoke with increased tension has room to straighten and transfer load to it's partner. As I said, I don't know if it can be felt, since things like spoke gauge, and tire design and pressure are much more important, but maybe. OTOH, the hub can feel the difference, which is one of the reasons hub makers hate radial lacing.

BTW- experienced track riders who know their bikes do consistently report better steering response with radial front wheels, so there is something to the notion that it can be felt.

Jarrett2

Good stuff, thanks for the info.

At any rate, I got the 32 spoke wheel fixed up and back on the bike now.

Bill Kapaun

I weigh 250ish and run 100/110 for general poking around.
IF I plan on riding a lot of miles in a day, I'll add 10 PSI to both.

IF I were you, I'd drop 10 PSI in the front unless you have severe potholes etc.

fietsbob

The chance of a radially Spoked wheel's spoke tearing the edge of the hole out of the Hub Is certainly greater .

Jarrett2

Thanks.

HillRider

True, unless the hub manufacturer is specifically states it to be suitable for radial spoking. Many do these days and some front hubs are designed only for radial lacing like the Shimano WH-R560 wheel I described above. The flanges are designed so that cross lacing cannot be done.

dabac

For the same spoke count and gauge, a wheel built heads-in radial will be decidedly measurably stiffer laterally than both heads-out and crossed patterns, which might well transfer into a detectable difference in steering response.

But if they claim better steering from heads-out radials, I wouldn't be convinced.