Thread: Semi-fat bikes (27.5+)

Has anyone got one? Looking at getting a Surly ECR for cruising the local tracks and some bikepacking missions. Have never ridden a semi-fat and wonder if the rolling resistance is just going to make me hate life on easy gravel or road sections

Originally Posted by gimp

Has anyone got one? Looking at getting a Surly ECR for cruising the local tracks and some bikepacking missions. Have never ridden a semi-fat and wonder if the rolling resistance is just going to make me hate life on easy gravel or road sections

I'm sure there was an older thread on them on here, or maybe it was FnH?

I have a Stump Jumper 6 Fattie (27.5+) Had it for about 4 years and love it. I cannot recommend it highly enough.
Pros - great traction, supple and very forgiving ride. (you can get a line completely wrong and still bomb it)
Cons - slightly more roll resistance but only noticeable on smooth surfaces ie sealed roads.
I was out on it today and would never go back to skinny tyres.

Like everything, the answer is 'it depends'. If your normal riding is about going as fast as possible and you ride with a racer mentality you will absolutely hate it on smoother stuff.

If you load it up to go on a mission and just sit back and enjoy the ride, you'll wonder why you didn't do it sooner... ��

Surly is great - solid, durable - yes. Refined they are not! I have two - a Cross Check that has been beaten solidly for years and isn't getting worn in yet. Also an original Karate Monkey that has been tweaked for bike-packing - runs 29 * 2.4 tyres currently. Did a few trips on those tyres. If I hadn't had a bit of an oopsie on the trail bike I was about to put some 27.5+ wheels and tyres in it as more volume is more betterer for loaded off road touring. The more off-road it is, the more volume is the answer. For more Brevet style riding, stick to 29".

Its a bit counter-intuitive to most people but the fatter tyres have measurably less rolling resistance on anything rough, its only really on sealed roads that you might find them a bit more draggy.

There are in between options too, some bikes have enough frame clearance to run 29x2.6" or even 2.8" tyres. When I wear out the 2.3" on mine I will probably try out 2.5".

combined with an ebike and it might be interesting....

Originally Posted by Micky Duck

combined with an ebike and it might be interesting....

Yeah. They do them.

Well this is leaving me thinking maybe I should stick to a more standard tire width considering the road k's I do, which is leaving me unsure of what the heck bike I want because most of the Surly off road options are rigid + semi fat


Maybe I'll just convert my old Giant to a 1x11 or something and that will make me happier

Altho the ECR can run 27.5x2.8 so that might be a good compromise

There are quite a few bikes which can take a regular 29" or a 27.5+, the overall rolling radius is similar. Some people have 2 wheelsets and swap them over depending where they are riding.

That might be overcomplicating it though, for what it sounds like you will be riding I'd probably just go with a 29er hardtail. 29" wheels do roll along very well.

I don't know anything about Surly bikes so can't comment on them in particular.

Well I've done 530km in the last 2 weeks and probably 40% of them have been on sealed road so it's a reasonably high portion of my time. On an old 26" Giant hardtail. Was looking at 27.5" hardtails but there doesn't seem to be much choice

Yeah that is a lot of road riding. 29" rolls along so much faster and smoother than 26", I went straight from 26" to 29" when I updated last year so haven't done much direct comparison with 27.5".

As much as people will knock 26" wheels now, people were really happy with them for decades. Bigger wheels will roll better but if you aren't riding (racing) over lumpy stuff spending a couple of grand on something new may be a waste of money. If I remember, the Speciaiized Fuze is B+ (or 29er) hardtail.

Originally Posted by gimp

Well I've done 530km in the last 2 weeks and probably 40% of them have been on sealed road so it's a reasonably high portion of my time. On an old 26" Giant hardtail. Was looking at 27.5" hardtails but there doesn't seem to be much choice

It's sounding like you want two bikes - something for fitness and going places and another for bike-packing/adventures.

Have you considered one of the newer breed of drop-bar bikes that will take up to 700*50 or 650(27.5)*2.2?

Then have a semi-fat or full fat bike set up for adventuring.

Here's the sort of thing I mean:

https://www.konaworld.com/libre.cfm

Theres loads of options out there these days.