Originally posted this on the fatty site but thought it might be of interest to some of you that don't visit there. Was out testing different front wheels, back to back, on the Jones. Front wheel is the one of my Pugsley and the other is a 29+ I had built.
" Ok, so I promised/threatened a back to back test a few weeks ago and today the weather aligned with a day off, so I braved a trip to deepest, darkest Fife (not for the faint hearted) to run a couple of back to back laps with different front wheels in the Jones. Obviously it's just my opinion in one type of terrain but it made for a quite interesting comparison.
Test bike was my Jones Spaceframe with alfine 8 gearing on a Rabbit Hole rim and a WTB 2.3 Exiwolf on the rear.
26 fat front is a Nate mounted to a Rolling Darryl, spinning on a Jones Hub.
29+ is a Dirt Wizard mounted to a Rabbit Hole, on a Hope Fatsno.
Both wheels are running Surly inner tubes.
https://flic.kr/p/ACgxWe by
Steven Clubb, on Flickr
The loop I chose at Tentsmuir had a bit of everything. Nice flowing singletrack, some tight twisty stuff, fireroad and a horrible, soggy grassy drag. Trail surface varied from hardpack to compacted sandy dune trails and mud, oh lots of mud! Only thing missing was some proper climbing and descending, it wold have been nice to compare both wheels on some steep descents, especially in muddy conditions.
I did try and be semi-replicable on the laps choosing pretty much the same lines where I could and tried to ride at a pace I could duplicate, but I chose a bit too long of a loop for the conditions and ended up pretty knackered after the first. Strava'd the laps separately and lap 2 with the 29+ was only 4 minutes slower (over an hour lap) than my first. The final Strava segment came right at the end of the lap and was a flowing piece of singletrack and I was only 1 sec slower second time round when my legs were shagged. A fitter rider than me could probably produce noticeably quicker times on the 29+.
The fat tyre lap felt like every other time I've ridden there. The extra weight of the wheel could be felt on the rolling, tight sections where speed needed to be regained quickly. Grip was phenomenal in the tight turns though, with huge confidence in late braking. There's no getting away from the drag on the fireroads, even once up to speed. This was especially noticeable on the long soggy section. The float of the Nate was great in deep mud when then grip from the side knobs came into play, but was actually a bit of a hinderance in shallower mud where the wide paddle tread wandered on the surface layer of mud on top of a hard base. This could no doubt be improved upon by lowering the pressure to spread the tread but would drag even more on the firm trails. The trails where the fat front really excelled were the ones with a lot of surface chatter. The Nate just rolled right over all the rooty bits that buck a smaller tyre around. One particular section near the stables was badly cut up by horses but the front handled it so much better than the smaller tyre on the rear. The extra width of the front and lower pressure just sucked up all the hoof divots.
After changing the front wheel over, I had a bit of a rest and headed out on lap 2.
Immediately I noticed the weight loss. The bike felt far more lively and responsive, accelerating quickly. It was knocked around more in the rooty sections and I could feel more of the trail vibrations through the bars, but it was paid back in a bike that changed direction quicker. Even with a lap in the legs the difference on the fire roads was marked, with the bike rolling further when freewheeling the same sections as earlier. The shallow mud that had Nate squirming was not a problem, with the Dirt Wizard cutting down to the firm surface underneath. Even the deeper mud wasn't a problem and only when turning in the deepest parts could I feel the tyre lose its line as the mud pressed against the sidewall of the tyre. The stable trail however was noticeably slower, with the front getting hung up in the hoof marks that Nate just flattened. I struggled to carry any speed through it and just dumped some gears and had to grind it out.
So where does this leave us? Like I said this was mainly just for my own amusement but I did come to some conclusions.
Firstly for most of the riding I'll be doing on this bike, the 29+ front is a better option. The bike just feels more fun. The benefits to acceleration and change of direction are just too big to ignore. The Dirt Wizard gripped amazingly in all conditions I rode today and I think by the time the benefits of the Nate start to shine, the rear of a half fat will be struggling to make it through anyway.
Where I think I'd use the fat front would be on rocky trails, where the extra cushioning would be a big advantage. The trails around Aviemore spring to mind, with their loose, rubbly surface. On that type of more open trail, the ability of the fat front to bulldoze through would be of more benefit than the extra nimbleness of the 29+. "