Gravel Bike

Trips, adventures, bikes, equipment, etc.
steve.y.griffith
Posts: 354
Joined: 27 Aug 2007, 8:14pm
Location: North London

Re: Gravel Bike

Postby steve.y.griffith » 17 Feb 2021, 12:44pm

Nice picture whilst it’s encouraging more riders want to go off road I can’t see a gravel bike without mudguards as suitable especially in the U.K..
I learnt many years ago that the key requirements for an off road bike include :
- mudguards
- good tyre clearance

Neither of which Gravel bikes seem to have .It does look to my like a clever marketing strategy . There is one benefit it has increased the range of off road tyres in 700c.

PH
Posts: 9947
Joined: 21 Jan 2007, 12:31am
Location: Derby
Contact:

Re: Gravel Bike

Postby PH » 17 Feb 2021, 7:27pm

steve.y.griffith wrote:Nice picture whilst it’s encouraging more riders want to go off road I can’t see a gravel bike without mudguards as suitable especially in the U.K..
I learnt many years ago that the key requirements for an off road bike include :
- mudguards
- good tyre clearance

Neither of which Gravel bikes seem to have .It does look to my like a clever marketing strategy . There is one benefit it has increased the range of off road tyres in 700c.

Nearly every gravel bike I've seen has the fittings and space to fit mudguards and plenty of tyre clearance, unlike the fashionable bikes from a few years ago. What bikes have you been looking at?

steve.y.griffith
Posts: 354
Joined: 27 Aug 2007, 8:14pm
Location: North London

Re: Gravel Bike

Postby steve.y.griffith » 17 Feb 2021, 8:03pm

The last image in this thread the On One in N Wales ..

Stevek76
Posts: 702
Joined: 28 Jul 2015, 11:23am

Re: Gravel Bike

Postby Stevek76 » 17 Feb 2021, 8:29pm

According to PX that bike has rear rack, mudguard (the fork mounts are on the inside - you see this on a few bikes now) and 3 bottle cage mounts. Clearance is up to 47mm for 650b, 40mm for 700c.

There are bikes with larger clearances about, but 'gravel' is a wide range.

mattsccm
Posts: 3660
Joined: 28 Nov 2009, 9:44pm

Re: Gravel Bike

Postby mattsccm » 18 Feb 2021, 1:05pm

However, virtually all gravel bike riders seem to be out for a few hours so getting plastered is not an issue. :roll:

User avatar
CJ
Posts: 3112
Joined: 15 Jan 2007, 9:55pm

Re: Gravel Bike

Postby CJ » 19 Feb 2021, 12:52pm

Bmblbzzz wrote:Out of curiousity, what makes you rate Vaude so highly? Especially as they've never really been widely available in UK. I don't even know anyone who's got any of it, to my memory. But I do remember a pannier test in, I think, Cycling Plus magazine something like 20 or 21 years ago, in which they mentioned Vaude as being regarded in much of Europe on as high a level as Ortlieb, possibly even better.

Their designs just seem to be better in certain fundamental ways. Take this bag for example. Vaude chose the Rixen & Kaul attachment, which releases upward - whereas the Carradice seatpost bag system pivots down to release, so the bag interferes with the wheel! And Rixen & Kaul make two versions, the basic Contour attachment with a 50g bracket and a weak-looking metal and plastic support frame that's limited to a 2kg load, and the 70g Contour Max attachment with a much stronger-looking triangulated all-metal structure that I feel confident loading with more than it's claimed 3kg capacity.

Lots of brands offer bags on the basic Contour attachment, including Vaude with their 6lt Off Road 'S' bag, but why have only that, when by bolting a bracket weighing only 20g extra onto your seatpost you get the option of carrying another 4lt/1kg or more! Unfortunately few brands offer an bag with the structurally superior Contour Max attachment. In UK only Altura I think, have or had their Aero Post Pack (I can no longer find it on their website, only the odd mail-order shop) which at only 6lt fails to take advantage of what this bracket can carry. But it's cheap, so I bought one for a another bike. Inferior design again.

You mentioned Ortlieb and yes, in some ways Vaude panniers are better-designed even than this prestige brand. Ortlieb was one of the first to make all their panniers a symmetrical shape. This has the advantage that it doesn't matter which side of the bike you put them, which can however be a disadvantage when you rummage in the wrong one! The other disadvantage is heel strike: you either need a special bike with extra-long chainstays, or must mount them a really long way back on the luggage rack, where the weight has more effect on the handling of the bike. It is so much more sensible to make rear panniers assymetric, with a sloping forward edge, shifting as much load as far forward as it can be without interfering with your heels.

I have a Vaude rear pannier like that, one that they sent me for review, and sadly only the one. By that time all Ortliebs etc. were symmetric so it got a good review from me and I still use it, on the left on my shopping bike. Even sadder: it looks as though Vaude have also fallen victim to the stupidity of reviewers and bike shop staff, who know nothing about touring and think it's more important to be able to mount a pannier on either side of the bike, than it is to avoid the twin evils of heel strike and the tail wagging the dog!
Chris Juden
One lady owner, never raced or jumped.

Bmblbzzz
Posts: 3841
Joined: 18 May 2012, 7:56pm
Location: From here to there.

Re: Gravel Bike

Postby Bmblbzzz » 19 Feb 2021, 2:05pm

That prompted me to look at Vaude panniers. Yes, they're all symmetrical now. :( They're also "sustainable", "eco-friendly" and "fair and partnership based", which in practice seems to mean "PCF free". And, usefully, free delivery over £75!

Anyway, I'm sticking with my asymmetrical, made by exploitation of the downtrodden Lancashire workers, Carradice Super-Cs! (Never used the SQR thing; interesting to hear it pivots down to release, never would have occurred to me... )

User avatar
CJ
Posts: 3112
Joined: 15 Jan 2007, 9:55pm

Re: Gravel Bike

Postby CJ » 21 Feb 2021, 4:19pm

Stevek76 wrote:According to PX that bike has rear rack, mudguard (the fork mounts are on the inside - you see this on a few bikes now) and 3 bottle cage mounts. Clearance is up to 47mm for 650b, 40mm for 700c.

According to Planet X, but nowhere on their website does it define how much fresh air (over and above the actual tyre) they deem to be sufficient. And going by those two numbers, they don't have any fixed idea at all! My reason for saying that: half the difference between 622 (bead diameter of 700C) and 584 (650B) is 19mm. So if there's room for 47-584, there's only room for 28-622. If 40-622 fits at all, it fits 12mm closer to the absolute limit. So where the fcuk IS that limit? Nobody knows, but I'll guess it's a gnat's whisker from a 40mm 700C tyre!

When I bought my Mystique frame (from the same supplier) I resorted to scaling pictures on the screen, but was reassured by the fact they don't even suggest you need to go down a wheelsize to fit big tyres. If a supplier says that, you can forget about mudguards. And I got the result I wanted: SOooo much clearance I had to extend the brackets on the mudguard - to be sure the spray wouldn't miss it in a crosswind!

Stevek76 wrote:There are bikes with larger clearances about, but 'gravel' is a wide range.

True dat.

And if you're buying a gravel bike to get a tourer light enough to make the hills feel smaller, the Space Chicken should not be on your list. Like so many of this ilk, it's one ring short of a chainset!
Chris Juden
One lady owner, never raced or jumped.

amediasatex
Posts: 817
Joined: 2 Nov 2015, 12:51pm
Location: Sunny Devon! just East of the Moor

Re: Gravel Bike

Postby amediasatex » 21 Feb 2021, 7:12pm

The discrepancy above is almost certainly due to the limitation being the width in the chainstays rather than radially.

There are a lot of 'gravelly' bikes out there that can fit a 622x40mm but 'only' fit 584x47/48mm because of the width, even though they could fit 584x5+ radially.

As an example I've got one that can fit 622x52/53mm (without guards, 42mm with), but can still only manage to squeeze in 584x54mm width wise, but obviously that then gives some radial clearance for guards.

This seems to be because they're designing for road cranks and the lower Q-factor that comes with them rather than going with clearance for wider tyres but precluding the use for road cranks. This is probably a sensible compromise given the intended use but I share your frustration at manufacturers not actually revealing the useful bits of information like exactly what the clearances are radially, laterally, and at what rim diameter.

I've always thought a simple silhouette diagram of the stay and fork profiles from behind and above with the appropriate measurements would be easy to include on the geometry sheets.

Enigmadick
Posts: 88
Joined: 5 Mar 2016, 11:28am

Re: Gravel Bike

Postby Enigmadick » 21 Feb 2021, 8:05pm

And if you're buying a gravel bike to get a tourer light enough to make the hills feel smaller, the Space Chicken should not be on your list. Like so many of this ilk, it's one ring short of a chainset!


Don't agree. I've owned an Enigma Etape with 3x10 for about a decade and an On One Space Chicken 1x11 for 6 months now - and I'd happily tour on both. The gearing is totally fine but I will concede that after a week on the Chicken I might crave the more relaxing geometry of the Etape.

Love the Chicken though seen here at Flint Castle.
IMG_20210121_170020_697.jpg
ENIGMA DICK aka Richard Barrett

User avatar
CJ
Posts: 3112
Joined: 15 Jan 2007, 9:55pm

Re: Gravel Bike

Postby CJ » 24 Feb 2021, 6:44pm

Enigmadick wrote:
And if you're buying a gravel bike to get a tourer light enough to make the hills feel smaller, the Space Chicken should not be on your list. Like so many of this ilk, it's one ring short of a chainset!


Don't agree. I've owned an Enigma Etape with 3x10 for about a decade and an On One Space Chicken 1x11 for 6 months now - and I'd happily tour on both. The gearing is totally fine.

But I'm not content with "totally fine". I want a bottom at least that's totally AWESOME! :wink: And I won't 'go to eleven' to get it. Ten-speed stuff is already more wear-prone and expensive to replace than I'd like.

Do either your 3x10 or 1x11 provide a bottom gear as low as 18in? My 2x10 does (when I put the 24T inner on for touring) and yet it still has a 103in top. By using just two rings on a road triple crank I get an even closer chainline than a road double. My largest ring actually aligns with sprocket #6, but still runs smoothly with #1 (big-&-big) - just as you'd expect from the middle ring of a triple. By then however, I'm usually in the small ring, which aligns between #4 & #5 (the same ratio as big-&-big) and is never used with any sprocket higher (ie smaller) than #8. Thus I have a consistently better chainline and enjoy a more efficient transmission than any one-by, whilst also benefitting from a wider range of gears. All for the use of little brain-power when shifting. Two-by: it is the thinking man's transmission! 8)
Chris Juden
One lady owner, never raced or jumped.

esasjl
Posts: 7
Joined: 18 Feb 2021, 9:02pm

Re: Gravel Bike

Postby esasjl » 24 Feb 2021, 9:41pm

Maybe this thread is not really about transmissions, but the subject is relevant in the context. I've not tried 1x, nor advanced beyond 9s, but have played with 2x9 and 3x9. I've found 2 (46 (on chainline)-30) x 9 (11 - 42) very easy to use. 3 (48-36-26) x 9 (11-36) has slightly more range but takes more thought to use. With both its interesting that 90+% of the time I'm using these as 1x (46 with 11-42 and 36 with 11-36) systems even in quite heavy terrain. However, I do need the small rings on occasion (1 in 5 and steeper) and its useful to have a couple of longer gears on the triple. I guess a 1x with front 36 and rear 12s 9-50 gives about the same range and number of significant ratios but would need much more RD chain wrap and a longer chain that would be off-line more of the time.

rareposter
Posts: 250
Joined: 27 Aug 2014, 2:40pm

Re: Gravel Bike

Postby rareposter » 25 Feb 2021, 10:54am

steve.y.griffith wrote:Nice picture whilst it’s encouraging more riders want to go off road I can’t see a gravel bike without mudguards as suitable especially in the U.K..
I learnt many years ago that the key requirements for an off road bike include :
- mudguards
- good tyre clearance

Neither of which Gravel bikes seem to have .It does look to my like a clever marketing strategy . There is one benefit it has increased the range of off road tyres in 700c.


Most modern gravel bikes have all of that. Might not be "traditional" mudguards but something like a Mudhugger which clips or zip-ties on will easily mount with loads of clearance.

Clearance is greatly improved by the almost complete dominance of disc brakes (it's very difficult now to buy a rim-braked gravel bike). Tubeless tyres are possibly the single biggest contribution to enabling gravel bikes. There are a lot of "gravel-specific" transmission options now as well - lower gearing, wider spread of gears, tougher components.

But yeah, there's a huge variance in options from "slightly overbuilt road bike" right through "more or less a CX bike" to "nearly a mountain bike".