6/17/14 1:59 PM

Well I have most of my wheels converted to 23mm wide rims now. A few A23s sets, and one set with HED Belgium. And mostly 25+mm tires

What are you all finding with the wider rims and running a fatter tire. I am running 25-28s. Although the TT wheels and front Scott Belgium are 23s [for the go fast bikes ;) ]

Sold off the low spoke count wheels, except one set pretty much. I am overall getting a lot better ride, and [quantifiable] less flats. Both from lower pressures presumably. I am never over 90 lbs anymore, and always lower front by 8-10 lbs except when a 25 rear 23 front I same or maybe 2-3 lower front pressure. Not pinch flatted yet, well ever [never] on a road bike I can say.

Of my self/hand spun wheels, all the rears are 32 spoke 3x, 14/15 ga. rear or 14/15 with lighter non drive spokes. [DT-revo or SapimLasers]. Fronts; 24x Belguim, one A23 28 spoke, rest 32x with 14/15 or lighter front spokes, yada. The SS bikes also sporting wide rims as well.

Last wheel upgrade was the 10 speed Ultegra wheels on the Roubaix. Now running new Old Stock 25mm Axial Pros that are 27.5mm on the A23s. This thing rides better than anything I have ridden as far as comfort and especially comfort of road surface feel without any real speed/performance costs. Except as compared to the Scott in terms of Performance, last percentages maybe. ;)

The Paramount with the 28C GP4 All Seasons a very close second in comfort dept.

All anecdotal to a large degree. Buy maybe saying the following makes sense. The Colnago with 23C and open Pro rims seems to still have the old 'on rails' feel. Like the 21-2mm tubulars I need to sell off.

But an observation recently. I first mounted the 25C Axial Pros on narrow rims on the TCX Cross bike. They sit out at near the full 25mm on the narrow rims. I did not ride aggressive at all, riding with a casual rider that day. But @ 85 lbs of air, the bike never rode better. Almost easy to forget it was aluminum and stiff FWIW..

I would assume some flop if ridden aggressively.

Also, I can say a little negative trait I noticed. But not so bad a few lbs of air more would not remedy. On the Scott on a full power sprint the rear felt mushy/squirmy. Not that this happens too often. But I had not had enough power for a long time to cause this. Looking forward to what a few more months of keeping my ass steady on the bike brings.

6/18/14 12:14 PM

Sparky, you have hit on a topic that deserves a lot more attention than manufacturer's are placing on the issue of rim width and tire pressures. It seems that the tire companies have long assumed a (internal) rim width for road tires <= 19mm but with the advent of box rims like the A23 and my latest wheelset, HED Ardennes CL+ at 25mm (external), the rated pressures on the tires risk blow off if you go to max recommend pressure.
I called HED and they said the max pressure they would suggest for a 23-25c tire is 100psi which is what I am running on my Conti GP4000S_II in a 23. Wanted to ride on 25mm but ran into yet another issue that frame builders did not consider which is insufficient clearance to the brake (rear brake stay too low). These wider rim option are have a wide impact!

6/18/14 4:45 PM

Well, the narrowest tyre I use these days is 28mm Schwalbe Ultremo ZX on my Litespeed. They *just* fit between the seatstays and under the fork crown. But most of my riding is done on a couple of 650B bikes using either 38mm or 42mm tyres at around 45-50psi, which just float over any sort of crap road surface. And the fat tyres seem very little slower - I take those bikes out on bunch training rides...

I reckon this would be a machine I would like to own: http://www.gtbicycles.com/aus_en/gorogue/

6/18/14 5:16 PM

Carbon and gravel, I dunno bout that...

6/19/14 7:06 AM

I don't know much about BB drop numbers, but I would infer from the way the chainstays are built that this machine has a lower BB than usual.

6/19/14 7:38 AM

Seems to be an emerging genre, geared to dirt/gravel rides and riding like D2R2 and the Raid Rockingham ride Rick and I just did. While I am always interested in even remotely plausible rationales to get another bike, I'm happy with my good ol' steel Crosshairs with Clement LAS clinchers for this purpose. I tend to find myself in stuff a little gnarlier than packed gravel on occasion.

6/19/14 7:57 AM

Plus the fact that Dan is frequently complemented by other riders about his rig......

6/19/14 8:11 AM

quote:

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They *just* fit between the seatstays and under the fork crown.

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6/19/14 9:03 AM

BB drop in the GEOM chart on those shows 28CM.

Not low really. But they list two standovers, presumable with two different tires. But not two different BB heights?? I also like when Drop is listed and not height or both...

Off road anything tend to not have low BB generally.

Here is a 1st look article on the Grade.

http://www.bikerumor.com/2014/06/14/first-look-gravel-crushing-new-gt-grade-road-bike/


From Article: The slightly lower BB (somewhere between road and ‘cross bikes).

And a lower cost Alloy version too! But the welds sure affect the esthetic.




The right CX bike not too far from the mark, especially if disc?? Which mark is the question, do we need another 'mark' ?

6/19/14 3:07 PM

The specs on the GT web site show a BB drop of 70mm. That's not low - my Litespeed has 76mm BB drop, and several of my other frames have 80mm drop. I believe 80mm drop is what Richard Sachs uses on road frames.

6/19/14 3:46 PM

70 IMO is getting there, even on a road bike. But I guess gravel roads are pretty flat mostly. CX bikes/GEOM seem to have had a raised BB generally.
My TCX is pretty low actually IMO for a CX. Maybe why I like it. ;)

I seem to like it lower for the longer I will be riding personally. 70 would suite me fine for a road bike. Aggressive road/stage bike IIRC are 67ish, or less on some I think. My Strong is 75, the Scott 67, and the Nago close to the Scott. The Roubaix in the middle @ 70 FWIW.

6/19/14 4:32 PM

my Lemond Poprad has 74mm drop, and I wish it had more. One of the specs I would be firm on a custom road or cross/gravel grinder would be 8cm of drop.