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Wabatuckian

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Discussion starter · #1 ·
I'm trying to figure this out.

I rebuilt a wheel for my bike yesterday, threading in a new hub. I installed a Maxxis Ikon 120tpi that I got from another member here. Now my rear matches my front.

The other wheel, which I'm keeping for a backup, wears a WTB Ranger Comp, though I forget if it's a 30 or 60tpi. It's not more than 60.

I pumped the tires to 40 and 45psi for the road (which I always do if I'm not planning to go off-road,) and took the bike out on a test ride. As soon as I realized my rear wheel wasn't going to fall apart on me, I started giving it some speed.

I engaged my fork lockout, but the ride still seemed a lot smoother than I was used to, even on the road.

Additionally, I was going up a slight 2-3% grade and was surprised when I looked down and realized I was doing 18mph. The effort I was putting out usually sees me making 14-15mph on a flat road.

Now, I know higher thread count is supposed to provide less rolling resistance and increased comfort.

However, I'm rather surprised it was enough for me to notice, and am having trouble believing it's not just all in my head.

What do you think?
 
#3 ·
What's that "r" word you keep using? Can you at least pretend it's gravel or even a dirt "r" word? ;)

Comp is 30 tpi per the googles. Dunno how much it matters compared to tread pattern and rubber compound, which seem more important for what you're asking.

Also, at 40+ psi I'm not sure how supple a tire can be. Yes, I'm being serious. I keep mine in the low 20s even if I accidentally ride smooth stuff.
 
Discussion starter · #4 ·
noapathy said:
What's that "r" word you keep using? Can you at least pretend it's gravel or even a dirt "r" word? ;)

Comp is 30 tpi per the googles. Dunno how much it matters compared to tread pattern and rubber compound, which seem more important for what you're asking.

Also, at 40+ psi I'm not sure how supple a tire can be. Yes, I'm being serious. I keep mine in the low 20s even if I accidentally ride smooth stuff.
Click to expand...
I ride on everything, man. Even pavement, sometimes, when I'm testing something or don't have a choice.

The sidewalks here are fun. Some of them would rate up to a blue square. I'm serious.

My bike is built for exploring, though. That's my thing. If I have to take unbroken pavement, I will. What I want to see is usually tucked way back in unpaved places, though.
 
#5 ·
I had Rangers and they seemed OK although not as fast as the Specialized FastTraks I had before or the Rekon Race I have now. The Ranger has widely spaced knows and I think those will give a lot more drag than the closely spaced small knows on the Maxxis tires.
 
#10 ·
If you are riding in the R0@d, have a look at Silca to get a better starting tire pressure:

silca.cc

SILCA Professional Tire Pressure Calculator

Dial in your bikes' tire pressure to get the most comfort, speed, and efficiency on your ride. If you are looking for the best free marginal gain, click here
silca.cc

Threads per inch is only one part of how stiff or supple a tire feels. And as far as rolling resistance goes, at those high pressures, I would expect compund to matter much more, as well as tread pattern.
 
Discussion starter · #11 ·
Tjaard said:
If you are riding in the R0@d, have a look at Silca to get a better starting tire pressure:

silca.cc

SILCA Professional Tire Pressure Calculator

Dial in your bikes' tire pressure to get the most comfort, speed, and efficiency on your ride. If you are looking for the best free marginal gain, click here
silca.cc

Threads per inch is only one part of how stiff or supple a tire feels. And as far as rolling resistance goes, at those high pressures, I would expect compund to matter much more, as well as tread pattern.
Click to expand...
I'm usually not on the road for any distance. This was just to test the rear wheel.
 
#12 ·
Wabatuckian said:
I ride on everything, man. Even pavement, sometimes, when I'm testing something or don't have a choice.

The sidewalks here are fun. Some of them would rate up to a blue square. I'm serious.

My bike is built for exploring, though. That's my thing. If I have to take unbroken pavement, I will. What I want to see is usually tucked way back in unpaved places, though.
Click to expand...
I was just teasing you (even remembered to use the ;) this time). :)

If I rode those things more often, I'd consider a semi-slick with decent cornering knobs. Oh wait, I have that exact thing on the rear of 2 bikes where rolling resistance matters more. They're actually quite heavy, but they roll well so the weight is not too noticeable compared to the lighter but more aggressive (slower) tires they replaced (those will go on the front later). Surprisingly, they also have plenty of grip in most cases with only a slight decrease in braking ability, but the front does most of the stopping anyway.

Depending what your frame will fit, you might even look into some gravel/cross tires. They make them wider these days...almost like skinny mtb tires. Great for multi-use scenarios like you describe.
 
#13 ·
Wabatuckian said:
Additionally, I was going up a slight 2-3% grade and was surprised when I looked down and realized I was doing 18mph. The effort I was putting out usually sees me making 14-15mph on a flat road.

Now, I know higher thread count is supposed to provide less rolling resistance and increased comfort.

However, I'm rather surprised it was enough for me to notice, and am having trouble believing it's not just all in my head.

What do you think?
Click to expand...
The difference between 15 to 18 mph on a flat road is 60+ watts. You don't want to know the difference at 18 mph and a 2% grade, but you can Google just as well as I can. Butt dynos just don't work very well.

Sounds like you like the tire and I'm sure there's some difference - just not nearly this much. So it's a win.
 
Discussion starter · #14 ·
goldsbar said:
The difference between 15 to 18 mph on a flat road is 60+ watts. You don't want to know the difference at 18 mph and a 2% grade, but you can Google just as well as I can. Butt dynos just don't work very well.

Sounds like you like the tire and I'm sure there's some difference - just not nearly this much. So it's a win.
Click to expand...
I'm not entirely sure what you're saying.

Is 60w considered a lot in this instance?

The reason I'm asking is that the bike computer program I used to use had me putting out 500w peak most times I road and a bit above 600w once or twice when I pushed it.

I don't have a power sensor, so I guess this was an algorithm calculation from speed, acceleration and mass? Dunno. I have no idea its accuracy or how those numbers compare.

Point is, 60w just doesn't sound like a lot by comparison. Is it though?
 
Discussion starter · #15 ·
noapathy said:
I was just teasing you (even remembered to use the ;) this time). :)

If I rode those things more often, I'd consider a semi-slick with decent cornering knobs. Oh wait, I have that exact thing on the rear of 2 bikes where rolling resistance matters more. They're actually quite heavy, but they roll well so the weight is not too noticeable compared to the lighter but more aggressive (slower) tires they replaced (those will go on the front later). Surprisingly, they also have plenty of grip in most cases with only a slight decrease in braking ability, but the front does most of the stopping anyway.

Depending what your frame will fit, you might even look into some gravel/cross tires. They make them wider these days...almost like skinny mtb tires. Great for multi-use scenarios like you describe.
Click to expand...
I have some 700c gravel tires out in the garage. A couple Ilmfat sent me, and a couple I picked up for a couple bucks apiece.

The issue I have with trying them is that I ride on chunky, sharp rocks a lot, and I'm not sure how those tires would react or feel on those rocks. It gets difficult to stay upright a lot of the time, as it is.
 
Discussion starter · #16 ·
noapathy said:
I was just teasing you (even remembered to use the ;) this time). :)

If I rode those things more often, I'd consider a semi-slick with decent cornering knobs. Oh wait, I have that exact thing on the rear of 2 bikes where rolling resistance matters more. They're actually quite heavy, but they roll well so the weight is not too noticeable compared to the lighter but more aggressive (slower) tires they replaced (those will go on the front later). Surprisingly, they also have plenty of grip in most cases with only a slight decrease in braking ability, but the front does most of the stopping anyway.

Depending what your frame will fit, you might even look into some gravel/cross tires. They make them wider these days...almost like skinny mtb tires. Great for multi-use scenarios like you describe.
Click to expand...
These are the gravel tires I have, two each. The Bontragers are 700c x 40 and the Panaracers are 700c x 50. The tread just doesn't inspire confidence on wet rocks, but I've not tried them, either. What do you think?

Image
Image
Image
 
#17 ·
Wabatuckian said:
The issue I have with trying them is that I ride on chunky, sharp rocks a lot, and I'm not sure how those tires would react or feel on those rocks. It gets difficult to stay upright a lot of the time, as it is.
Click to expand...
I'm definitely not an expert by any stretch. Sharp rocks...not a lot to say other than how thick is the casing? I'm guessing not very, but if I'm reading their charts right the Panaracers are almost 600g which would imply they'd be more durable. Whether that holds true, dunno. I like the tread pattern of the Bontrager better TBH. Looks like a pared down XC race tire.
Wabatuckian said:
These are the gravel tires I have, two each. The Bontragers are 700c x 40 and the Panaracers are 700c x 50. The tread just doesn't inspire confidence on wet rocks, but I've not tried them, either. What do you think?
Click to expand...
Those are both pretty nice tires for gravel road riding.

Wet rocks can mean a lot of different things. Slippy limestone, nothing's gonna grip but softer rubber, higher TPI and lower pressure can each help a tiny bit. Grippy sandstone...all good. But with the amount of exploring you do, I figure you'll encounter a good deal of variety. Tires can only do so much and then it's up to the rider.
 
#18 ·
FWIW I've taken my gravel bike onto singletrack like 3 or 4 times. I just rode considerably slower over the rougher stuff and skipped/walked anything that felt too sketchy. The tires are some el cheapo generic 38c nearly smooth tread that Diamondback put on stock. Happy exploring! :)
 
#19 ·
Wabatuckian said:
I'm not entirely sure what you're saying.

Is 60w considered a lot in this instance?

The reason I'm asking is that the bike computer program I used to use had me putting out 500w peak most times I road and a bit above 600w once or twice when I pushed it.

I don't have a power sensor, so I guess this was an algorithm calculation from speed, acceleration and mass? Dunno. I have no idea its accuracy or how those numbers compare.

Point is, 60w just doesn't sound like a lot by comparison. Is it though?
Click to expand...
60w is quite a difference. If you don’t have a power meter, it’s hard to know. But I’d really doubt you’re cruising at 500w on average n your bike (no offense).

For what it’s worth, Tour de France riders have an FTP in the 400-450w range. The FTP is the amount of power a person can produce for one hour.

Most casual cyclists are in the 150-250w range. Serious/semi-trained riders are probably in the 250-350w range.

I’m a relatively average cyclist, with an FTP of ~267w the last time I checked. I can do 300w or so for a few minutes pretty easily, but there is no way I could “cruise” at 500w. I can bust out 1000w plus pretty easily… but not for more than a few seconds.

Anyway, I’m not trying to brag. Just chiming in to mention that 60w, is generally considered a pretty large wattage difference. For a smaller rider who is untrained, that could be about 1/3 of their power output.
 
#20 ·
Yea the power figures through me off a bit too. What I do know is a heavy dh casing semi slick tyre in super tacky rolly crap on road even though the tread pattern is so low purely from the weight and sticky rubber, though I will say the stiff casing does transmit every single shock and pothole at least at high psi for road. A rock razer that is a similar tread pattern but in speed grip compound and much lighter casing rolls miles faster. So I would say primarily it's compound and weight, and then tread pattern and lastly how many threads per inch.
 
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