Fat bike riding dynamics vs. "normal" bike.

[Lost]

So, just drained the battery (almost) on my Rover.
Mostly on streets, some unplowed until I slid past my comfort zone.

Anyway, I notice the steering is distinctly different in that once a turn is started, you need to apply a restoring torque in the middle of the turn. If I tried (I didn't) hands off, it seems it would crumple up because once a turn is started, the wheel wants to continue into the turn.

Is this normal, or is it a function of something I can adjust like tire pressure?

 

[mrgold35]

I think it might be the combo of the contact patch of the fat tires, PSI, and the momentum of the wheel when it starts to turn. The fat tires on the RR reminds me of the experiment in high school when a kid sits on stool and the teacher spins a bike tire so the kid can rotate the stool in a circle with the bike wheel momentum only as they tilt the wheel in either direction.

I have to be careful trail riding and hitting a tight turn too fast because the front fat tire knobs can really dig in having the same effect of applying the front brakes too hard. Learned to tap or apply the rear brakes first before a tight turn to bleed of speed. I use both brakes if I need to slow down or stop while mostly going straight.

Almost have to ride the Radrover like a dirt bike and lean into turns and shift your center of gravity for traction.

 

[LimboJim]

I've seen this effect called "self-steering." At low PSI, more of the side of the tire contacts the riding surface, and turning gets amplified by increased frictional pull. It's not as noticeable on soft surfaces, and some fat tires are more prone to it than others.

In my experience, Vee Missions and Vee8s have the most self-steer, while the Kenda Juggernauts that Radrover and so many others come "standard" with have a bit less.

Schwalbe Jumbo Jims, however, can be run at very low pressure with negligible self-steer. They also have more grip in wet conditions, better traction off-road, and lower rolling resistance on pavement.

 

[vincent]

Thanks for the info on your experiences with the tires

Sounds like maybe some of us need to try the jumbo jims

Any thoughts on how those might do in a dry desert type terrain?
With bad thorns, hard packed trails with some sand areas on them ...

 

[LimboJim]

Schwalbe has "Lite" and "Snakeskin" versions in 4" and 4.8" sizes- my Felt LEBOWSKe came stocked with smaller Lites and had a flat early on. I found some Snakeskin larges on sale at bike-discount.de and haven't changed or repaired a tube since (700 trail miles). They are also superb snow tires - worth every cent!

I then lined some 3" wide Gorilla tape (way cheaper than Mr Tuffy liners) inside the 4" Lite tires and swapped them with my iZip Sumo's Juggernauts (which had more than their share of flats) ... huge improvement! So much nimbler (more nimble?), it's a totally different bike - and no flats in over 500 trail miles on that bike.

Full disclosure: I sold my Radrover with just 100 miles on it... I needed a much more rugged trail bike (and ended up with a couple, thanks to demo prices and a wicked case of ebike fever).

 

[Lost]

and a wicked case of ebike fever).

If I get a case of that fever, my wife is going to get torqued! I tend to go all in when I get into something, and this one has her concerned I think.

I really do not need total fat bike tires, I doubt I will ever be on sand, mostly on roads (not all paved though) and the occasional path. I will definitively try a narrower tire next, which maybe will attenuate the self steering. Maybe the snakeskins? More research needed, but I've got plenty of time for that too.

 

[LimboJim]

Seems like several folks have posted liking Maxxis Hookworms for fattie street use. No knobs though, so I'd look into their performance on dirt roads...

 

[mrgold35]

I haven't found an "all terrain" version of a 4" fat tire yet (kinda like an all season car tire being a jack of all trades and master of none). There seems to be a group of various styles and traction levels from ice, snow, loose sandy trail, or hard packed trail. Then there is a group for urban with very light hard packed trail. I haven't found a lot of choices that bridges the gap between the two groups.

I just purchased the Vee 8 120 tpi 4" fat tire for my Radrover. This tires seems to be close bridging the gap and made for the middle of the road riding of hard packed trail traction to paved roads quietness. I hope the Vee 8 lower paved road noise, longer treadlife, little to none hard packed trail traction lost.

(Link Removed - No Longer Exists)

 

[Lost]

Just found this article about self steer and slick tires. Another tire worthy of consideration? https://fat-bike.com/2016/12/vee-ti...nt=Vee+Tire+Apache+Fatty+Slick+-+The+KBS+Take

EDIT: Maybe not. "The flip side of this BRAP-ability is that the tires are absolute death machines if it gets wet or there are leaves on the trails. Wet roots and logs are super scary because the lack of knobs allow the tire to go from gripping the dirt to slip and slide in an instant. The lack of knobs also don’t help you to punch through the leaves at all"