Grand Bois - Intial Rides

[dirtdigger88]

with winter coming on full force Ive been on the rollers far more than the road over the last few weeks-

however- the last weekend I did manage to get a couple of rides in on my new Grand Bois tires

Thoughts-

they are a nice tire over all- they are made my panaracer so they are really like many of the companies other tires- think rolly polly or jack browns

looks- they look like a tan side walled version of my Vittoria 24mm CX tires- just a bit bigger

as far as size - they are really not much bigger than a Michelin Pro Race 25-they are for sure smaller than the tufo D28 tubulars

I have not tried them under my F2 fork- my bet is that they will fit- but they will be too tight for my liking

the tire is nice and round- but there are a few spots where to black rubber is not even as it meets the tan sidewall- it doesnt mean anything other than if you look at the tire will spinning - it LOOKS likes its slight out of round- but its not-

the tires have a good road feel- better than the rolly pollys I have tired in the past-

one of my tests of a tire is to haul @ss down my street (usually at the end of a ride) and see how fast and hard I can take the cul-de-sac

these tires stick well when being pushed hard in a corner- they did not feel like they were going to give out on me

I am going to say these tires fall somewhere inbetween a Michelin Pro Race and a Vittoria/Veloflex- they feel a bit more "grippy" than the PR but not as supple as the Vitts/Velos

I can tell that these tires are ment to be a larger "fast" tire rather than a "skinny" touring tire- they are happier with the PSI up a bit higher than I had thought they would

Jan also made it a point to tell me that they will not be as flat proof as a Pasalea TG or the likes-

the sidewall say inflate to 105psi- I tired below 80 (thinking like a Pasalea) but the tires just felt sluggish rather than comfortable

at 105 psi the tires are way too hard for me- I am finding the sweet spot around the 85- 90 psi range-

I cant comment on the durability of the tires- I just have not had them long enough-

Ill comment back after I have a few more miles on them- Ill let you know how they are holding up

Jason

[Steve Hampsten]

Good review, dewd...ok, I'll try them. I'm building a new fender bike and it needs rubber.

How are the Tufo cross tires on pavement? Workable?

[dirtdigger88]

workable yes-

but not really the best set up - they turn you bike into a monster truck for sure

Jason

[dauwhe]

I'm guessing these are the 28mm version and not the 30mm?

Dave

[dirtdigger88]

I'm guessing these are the 28mm version and not the 30mm?

Dave

yes- sorry

Jason

[jthurow]

How are the Tufo cross tires on pavement? Workable?

I was running the D28s on my Ram, which I use for commuting. I usually run Roly-Polys on a 36 spoke touring wheelset when commuting and compared to them, the D28s (which were on 32 spoke PR rims) were like riding on a fast moving cloud. My biggest complaint was that they were fragile. I think I got 3 punctures in as many months.

jimi

[paczki]

Dirtdigger,

Any further thoughts? Worth switching from Rolly Pollys on my Rivendell?

[Samster]

hey dirt! are you really down to one bike?? i've been away for a while... busy, sick... busy being sick... etc.

[dirtdigger88]

paczki- I wouldn't dump perfectly good RT for the GBs- but I would make the switch when the time came-

sam- yes sir . . . one bike . . . for now

Jason

[dbrk]

snip...
Any further thoughts? Worth switching from Rolly Pollys on my Rivendell?

I've ridden the Rivendell tires since their inception and have now put real miles on the Gran Bois in 28c and 30c. I think the GB don't wear as well as the Rivendells but they are comparably soft. I prefer the Roly Poly to the Ruffy Tuffy. But unless I'm trying to notice which brand I'm on, I can't tell the difference. Tires are like lots of things, say shoes, shifters, and saddles: it's a personal thing ---such that reviews in BQ, which make at an effort at empirical even scientific evaluation strike me as well-informed, patiently tested preference that create an interesting influence on people's perceptions. I have no idea how a tire could be really be tested in ways that would persuade me of more than a person's experience but it's always good to hear about such experiences. Mine is simple: I love the Rivendell PR and the Gran Bois and unless you just want to try something different, I'd not spend the money yet to switch.

dbrk

[fixednwinter]

dd88;

Thanks for the detailed review and comments. This will come in useful for my gravel road bike - I want to try several types of tires for it, including the GB's.

[Spinner]

... your eye for detail shines through. compelling story line too. makes me want to go ride a bike ...

... it's 38 degrees under sunny skies with five inches of snow on the ground. i just pumped 95 pounds into my rol-y poly skins. it's rambouillet day.

cheers.

[paczki]

Thanks, great info :banana:

[39cross]

....Worth switching from Rolly Pollys on my Rivendell?
Definitely - you can toss them my way! ;)

But seriously, I have an unmounted pair of GB 30's that you can try if they will fit.

[Polyglot]

I've ridden the Rivendell tires since their inception and have now put real miles on the Gran Bois in 28c and 30c. I think the GB don't wear as well as the Rivendells but they are comparably soft. I prefer the Roly Poly to the Ruffy Tuffy. But unless I'm trying to notice which brand I'm on, I can't tell the difference. Tires are like lots of things, say shoes, shifters, and saddles: it's a personal thing ---such that reviews in BQ, which make at an effort at empirical even scientific evaluation strike me as well-informed, patiently tested preference that create an interesting influence on people's perceptions. I have no idea how a tire could be really be tested in ways that would persuade me of more than a person's experience but it's always good to hear about such experiences. Mine is simple: I love the Rivendell PR and the Gran Bois and unless you just want to try something different, I'd not spend the money yet to switch.

dbrk

I agree with your take here but must admit to being VERY sceptical about whatever BQ writes about tires as 1) they earn money off of the sale of the tires that their tests end up hyping 2) their tests are generally fraught with poor scientific methodolgy.

[Pete Serotta]

the bike looks wonderful and those tires definitely aren't slowing him down. :D


Good review, dewd...ok, I'll try them. I'm building a new fender bike and it needs rubber.

How are the Tufo cross tires on pavement? Workable?

[goonster]

their tests are generally fraught with poor scientific methodolgy.

OK, I'll bite . . .

Please identify the poor methodology and, more importantly, propose a more rigorous analysis of real-world, measurable bike tire performance.

[Polyglot]

OK, I'll bite . . .

Please identify the poor methodology and, more importantly, propose a more rigorous analysis of real-world, measurable bike tire performance.

I think that you have answered your own question. Trying to insert real-world into scientific methodology is simply wrong as you cannot sufficiently control all the variables. To attempt to do so is plain wrong and guaranteed to fail from the outset. All recognized scientific testing involves controls of all possible variables, or at very least the most important ones. In the BQ testing they use a rider on a bike, which on its own inserts a degree of variability that surpasses most of the claimed differences between the tires tested. Then add all the other variables that were also neglected and you have results that are highly questionable. Then best of all, insert a product where the 'tester' or his sponsor has a financial stake in...

I'd love to see a pharmaceutical company go to the FDA with clinical trial results that were tested like this.

-------------------------------------------------

Le fait de vouloir quelque chose ne le rend pas nécessairement possible.

[goonster]

I'd love to see a pharmaceutical company go to the FDA with clinical trial results that were tested like this.


Ha!

Determining efficacy of medications in Stage 3 clinicals has everything to do with the perceptions of real-world people (e.g. pain medication) and the number of variables to control are pretty limited. Find a way to send Jan's guys down their inclined slope without knowing what tires they're riding, and the FDA will be all ears.

Jan doesn't need to be lectured on the scientific method. If anyone can think of a better way to test tires I'm sure he'd love to hear it. It's either his test, or the steel drum, and I'll take a bike with rider on a non-smooth surface every time.

[don compton]

i am on my second set of brand, 700x28"s. i really liked the first set and got about the same mileage as my michelens. with the second set i have a little problem. both the front and rear tires have , what appears to be, broken casings or belts. each tire has an area were there is a noticeable deformity. i think it might have happened when i hit a pothole. i am having second thoughts about buying another pair. ( by the way, i only have 300 miles on them) :crap:

[paczki]

Definitely - you can toss them my way! ;)

But seriously, I have an unmounted pair of GB 30's that you can try if they will fit.

Thanks, I may take you up on that :banana:

[dauwhe]

I think that you have answered your own question. Trying to insert real-world into scientific methodology is simply wrong as you cannot sufficiently control all the variables. To attempt to do so is plain wrong and guaranteed to fail from the outset. All recognized scientific testing involves controls of all possible variables, or at very least the most important ones. In the BQ testing they use a rider on a bike, which on its own inserts a degree of variability that surpasses most of the claimed differences between the tires tested. Then add all the other variables that were also neglected and you have results that are highly questionable. Then best of all, insert a product where the 'tester' or his sponsor has a financial stake in...

I'd love to see a pharmaceutical company go to the FDA with clinical trial results that were tested like this.

First, picking tires based on this test is unlikely to kill me, or to injure me. So I don't think the comparison to drug testing is appropriate.

Second, in the first round of tests, the Grand Bois tires did not do particularly well, even though Jan imported those tires. Are you questioning the integrity of the testers?

Third, their methodology seemed to be an improvement over any previous tire tests. I've never ridden a bike on a steel drum, and never intent to. The question they were asking is which tires would possibly be faster for regular riders, on ordinary roads. They tested this as best they could, and were very open about the procedure, what variables they were trying to control for, etc. People with much more knowledge of the physics of bicycles have reviewed and commented on the tests.

Fourth, their results seemed to make sense (in some nebulous way). There were reasonable explanations for why some tires were faster than others (thin tread, supple casings, wide body). The test results also matched up well with my experiences. I think the Nifty-Swifty WAS slow, as people noticed when we were coasting down hills at the Ramble. My Pro2Races feel faster than other similarly-sized 700c tires. So the results don't contradict my experiences, which they might if you think the results were completely random.

I think the whole experiment was very much in keeping with the scientific spirit. Rather than relying on previous authorities, or stories passed down from previous generations, they went out and tested, and measured.

How has this affected me? I've spent more time riding with Pro2 Race tires, and less on Ruffy-Tuffies. Even if they're completely wrong about everything, the consequences are small. I hope they've inspired people to improve on the tests, and further our understanding. That would be a great thing.

Dave

Disclosure: A few of my observations of 650B tires were published in VBQ in the same issue as the first tire test. I didn't know of the test results when I made my observations. I've never met Jan, but he did extend my subscription for a year in payment.