Help me figure out why I'm faster on my budget cross bike than I am on my steel weight weenie road bike.

[RNAV]

I did some more data analysis, and it turns out I've done slightly more climbing over the past 5 rides on the Washoe than the Crux.

Avg feet climbed / ride (past 5 rides):
Washoe = 1080 feet
Crux = 1008.6 feet

I don't think 72 feet of climbing (on average) would make that difference?

Also forgot to mention that I'm running Sram Red 22 chains waxed with Silca hot wax on both bikes. The gearing is different though:
Washoe = 52/36 crank, 11-28 cassette
Crux = 50/34 crank, 11-32 cassette

[DukeNiemand]

Can you compare cadence data? Since the Crux has lower gearing, there's a chance you might be using a higher cadence.

[TobinHatesYou]

Can you compare cadence data? Since the Crux has lower gearing, there's a chance you might be using a higher cadence.

He says power is similar….cadence doesn’t matter, though gear combo efficiency would have a very slight (negligible) effect.

[usr]

I did some more data analysis, and it turns out I've done slightly more climbing over the past 5 rides on the Washoe than the Crux.

Avg feet climbed / ride (past 5 rides):
Washoe = 1080 feet
Crux = 1008.6 feet

I don't think 72 feet of climbing (on average) would make that difference?

So different routes then? Not comparable at all. Average climbing per distance doesn't mean much. When you have many short up/down you'll be much closer to your average in the flats than with the same amount of climbing/descending concentrated in a few longer mountains. It's all about the energy lost downhill, to high speed drag and/or the brakes. That's assuming no sharp corners at the end of the down parts in the short up/down case, because those can sum up to quite considerable energy loss on a road hugging a mountain range (but still not as slow as the same amount of climbing in one go)

[TobinHatesYou]

Not to mention traffic, intersections, wind direction, road surface, etc. Zzzz.

[justkeepedaling]

If it's not even the same course, forget about comparing them

[naavt]

Buy or loan a PowerPod and see if your position on the bike is EFFECTIVELY the same. Any small change in your position due to different frame geometries can account for a different Cda which can account for those discrepancies.

Beyond that... make all those asumptions after making some miles/kms at a velodrome. That's the only way to diminish any of the differences you certainly encounter on EVERY ride you make, since no 2 rides are the same when you are facing external conditions.

[StanK]

Unnecessarily misleading title. No weight weenie bike, and both bikes are almost the same weight. Good luck with the rest.

[thewoodsman]

5 rides each, different climb/route/wind...not a large enough sample. And to do true averages, you need the time of each ride to properly weight the values.

However, I do think your tire pressure might be holding some losses. For your weight (you+bike), the psi of your 25c tires seems a bit low, even for a softer feel, and the psi of the 32c is more on the firm side. So the comparison is going to be affected by the relative difference. You say the roads are rough; I would try bumping up the 25c just a bit--upper 80s, maybe lower 90s. That could help with hysteretic losses. But your 32c, assuming same tires inflated to the same relative pressure, will be faster over most roads, especially rough roads. When I switched from 28-->35 the difference was pretty significant over rougher roads.

Also body position makes a huge difference.

[raggedtrousers]

Can you set up a local loop, say 10 miles, which is fairly free from traffic? If so, try and run a few back to back rides on the same day, swapping bikes. There are various apps and sites (UK tt-ers tend to use mywindsock) which will attempt to quantify the effect of weather.

Once you've done that a few times, you'll have an idea if one bike really is faster. It won't be scientific, but it should give you a good idea.

One final thing: does the Crux actually feel faster? I'd expect a bike where I was riding best part of 1mph faster at 10w less to feel noticeably quicker; that's actually very similar to the difference between my cx bike with road tyres and my road bike, and the latter definitely feels a bit sharper.

[RNAV]

5 rides each, different climb/route/wind...not a large enough sample. And to do true averages, you need the time of each ride to properly weight the values.

However, I do think your tire pressure might be holding some losses. For your weight (you+bike), the psi of your 25c tires seems a bit low, even for a softer feel, and the psi of the 32c is more on the firm side. So the comparison is going to be affected by the relative difference. You say the roads are rough; I would try bumping up the 25c just a bit--upper 80s, maybe lower 90s. That could help with hysteretic losses. But your 32c, assuming same tires inflated to the same relative pressure, will be faster over most roads, especially rough roads. When I switched from 28-->35 the difference was pretty significant over rougher roads.

Also body position makes a huge difference.

Yes, I agree I don't have a large enough sample size to truly make a reasonable comparison. I haven't had the Crux as long as the Washoe, and looking back at my data it seems I've only got 5 rides total where the route ridden was identical . . . and 2 of those rides were from 2 years ago. I do think you're probably onto something with the tire pressures. I think I'll try bumping up the 25c pressure to see if that helps. Thanks!

[RNAV]

Can you set up a local loop, say 10 miles, which is fairly free from traffic? If so, try and run a few back to back rides on the same day, swapping bikes. There are various apps and sites (UK tt-ers tend to use mywindsock) which will attempt to quantify the effect of weather.

Once you've done that a few times, you'll have an idea if one bike really is faster. It won't be scientific, but it should give you a good idea.

One final thing: does the Crux actually feel faster? I'd expect a bike where I was riding best part of 1mph faster at 10w less to feel noticeably quicker; that's actually very similar to the difference between my cx bike with road tyres and my road bike, and the latter definitely feels a bit sharper.

Great idea, and something I think I'll attempt when I get some time.

I wouldn't say the Crux feels faster . . . what I would say, though, is that I've noticed two things: 1) It's easier for me to not get dropped on the A group ride on the Crux, whereas I notice I frequently struggle to keep up with the Washoe, and 2) I noticed that given the same perceived level of exertion, I snag more PRs on the segments I ride frequently on the Crux vs. the Washoe. They both feel fast to me, it just seems like its easier to go fast on the Crux.

[TobinHatesYou]

Brainworms / placebo.

[DukeNiemand]

Any comparisons are pointless if the route isn't identical. The only other suggestion I'd make is to confirm you're using optimal tire pressures. Confirm with something like the Silca tire pressure calculator if your haven't already.

[Marin]

Yes, it's not real. Different bikes or weights make almost no difference. Rolling resistance effect is very small, rider position and kit is what matters most.

Here, the data is way too noisy. Do a rolldown test or Chung regression