Off-road Gravel Bike Limitations

Trips, adventures, bikes, equipment, etc.
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Re: Off-road Gravel Bike Limitations

Postby mattsccm » 16 Jun 2020, 12:36pm

A modern "gravel " bike is probably more robust and competent than a 1980s MTB.

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Re: Off-road Gravel Bike Limitations

Postby hemo » 16 Jun 2020, 7:39pm

I have a 2019 Arkose with 42mm 700c WTB's running TL, the rear will accommodate 50mm.

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Re: Off-road Gravel Bike Limitations

Postby GordonFreemanK » 17 Jun 2020, 12:41pm

I come from the same place as you: I bought a "road+" bike in 2014 (a Whyte Suffolk), which was advertised as CX although I think they were really aiming at commuting/day ride versatility. As with the CdF, it was conceived before the word Gravel had taken hold and even though they were going that way, they hadn't yet caught on the idea that this type of bikes need higher tyre clearance.

As a result, a 700x35c is a very tight fit on my bicycle with or without a fender (the limit is the width of the rear tyre at the chainstay level). Fine for commuting and light gravel, but the pleasure of riding lessens quickly as the gravel becomes rougher. I've been looking for a solution and I did reach the conclusion that I have to change bikes.

Before that becomes your conclusion too though I would consider for a second the possibility of getting a second set of wheels in 650b. Just a thought. I can't see any mention of 650b on Genesis litterature for this bike which makes sense because the bike was conceived before these new fashions. And besides the tyre clearance you also have to take in account that slightly smaller diameter wheels are going to lower the bike as well, in particular the bb position and height of the pedal at the lowest point might become problematic.

As for me, this isn't possibly really for me because the diameter of the wheel isn't the problem, the width of the rear tyre is. But I am definitely paying attention to this when browsing for my next bike now. I expect the bike maker to be explicit about the possibility of choosing between a 650b wheel with MTB tyre e.g. 2.0" and 700c wheel with regular touring tyres e.g. 40mm. Sounds more adaptable as it would be easier to change wheels before a ride as opposed to changing tyres. And cheaper than maintaining two bikes.

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Re: Off-road Gravel Bike Limitations

Postby mattsccm » 17 Jun 2020, 6:20pm

I tried the 650b idea by borrowing some wheels. On the bike that most needed it there was no more space around the tyre than with a 35mm semi slick 700c. About a 42mm with a similar pattern. Lost ground clearance as well. Might work but it will depend on the bike.

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Re: Off-road Gravel Bike Limitations

Postby Bmblbzzz » 17 Jun 2020, 7:22pm

kupukupu wrote:Hi hi
So my questions are:

1. How big can I go on the tyres? Genesis lists the max as 38mm but was shipped with 37mm already. Since I have an XL, can I go larger (or does frame size not matter)? Is there any chance (and benefit) of getting 650b wheels with wider tyres on instead?

Frame size won't make any difference. It's the clearance under the fork and the chainstays that matters. The manufacturer's tolerances of tyre-frame gap might be conservative, but better too much than too little. Measure and size down.

2. Have I bought the wrong bike? I naively didn't realize how limited and important the tyre clearance would be. I regret not spending more for a Vagabond with its 29x2.1, but I guess I got better components (and a lovely Reynolds 725 frame).  What is the advantage of the CDF 20 over a more "monster-cross" style adventure bike or a rigid mountain bike?

No, you have not bought the wrong bike. You've got a lovely 725 frame, good components and a bike with a very good reputation. It might be that this is the first rather than the last right bike.

3. What is your experience off-roading or bikepacking with the CDF or a similar gravel bike? I'd love any suggestions for longer UK routes!

I don't think I'd call the CdF a gravel bike - although that's a vague term, so it's not wrong. It started life as a cyclocross bike - and that, like gravel bikes I guess, is a road bike adapted to off-road use. It's definitely at the more road and touring (as opposed to racing) end of the gravel spectrum.

To sum it up: should I sell the CDF and get the "right bike", try to get bigger tyres or suck it up on what I've got, and/or keep the CDF as a road/gravel/intercity/commuter/exercise beast and save up for a mountain bike (a hardtail?) for backcountry bikepacking? I don't like to own a lot of stuff, but am willing to invest in the things I often use.

Sorry for the manyyyyy questions - I am slowing learning and appreciate any insights!

My advice would be keep the CdF and save up for either a hardtail or a 'gnarlier' drop-barred bike. If, after a suitable period of owning both, you find you're no longer using the CdF, that would be the time to sell it.

Richard Fairhurst
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Re: Off-road Gravel Bike Limitations

Postby Richard Fairhurst » 17 Jun 2020, 8:21pm

On a related note, I was fascinated to see this thread from 2008 when the Croix de Fer had just been introduced: viewtopic.php?t=18303 . Who'd have thought it would inspire a whole new genre of bikes? - maps, journey-planner, route guides and city guides