Self steer
 

Ok, I'm on a rant about my Pugsley, and fat bikes in general lately, but here's something I wish I had known more about before I built one: Self-steer.

It's irritating at best, and unnerving at the worst, when, for instance, you make a right-hand turn, and during the turn have to actively push back with your right hand to keep the tire from steering hard on its own into the turn. That, of course, is after you have to fight it off its line to force it to start turning. Turn mechanics that start with force, then oppose the turn, are simply not comfortable, and make for poor handling.

Just wanted to put that out there. This is one of the reasons I think that the fat bike trend is dying. What cyclist wants to put up with that after the novelty wears off, and what tire manufacturer wants to try to overcome that, while dealing with very unhappy customers who just dropped a lot of money on tires?

A Modern fat bike and decent tires does not self-steer even a low 3 psi pressures.

Not an issue I have with my fat bike.

One hater thread wasn't enough Banzai ?

You are free to place me on ignore and not reply. I'm happy to discuss self-steer, but if all you can do is personal jabs, it won't hurt my feelings if I make your "ignore" list. You will earn a spot on mine.

Teravail Coronado Tires.

Not much choice for tires anymore, either.

You come to fat bikes and bash fat bikes in every thread you post in. I'm for positive discussion. Is this a discussion about fixing a problem or about bashing fat bikes.

I have a pugs, never had a self steering issue...

I do not have the self steer issue with either my old Nates or my current Van Helgas.

The only time I ever feel anything like that is when I am running very low pressure for soft snow and then ride on a firm dirt road with a rut. The steering will tug a tad.

That is a load of crap.

It's you. Not the bike.

Low pressure on pavement will result in a little self steer but nothing like you describe. That and not sure why you would run low pressure on pavement. I don't have any self steer on the 2 fat bikes in my household.

The fat bike trend isn't dying. It's just that it's peaked.

I was under the impression that self steer was the bike having a tendency to turn without leaning. Or rather you'd turn but had to force the lean as it wasn't happening 'automatically' like it usually does. I had that happen with one pair of tires but after upgrading haven't noticed it happening unless I'm at 1psi pressure range.

Sound like what you're experiencing is either faulty hardware, user error or weight distribution that's way off whack (too much weight at the front wheel). Though bad weight distribution would fall under user error.

Usually with a fatbike I'll get understeer due to the gyroscopic effect the tires and wheels create and have to counter steer to prevent the bike from straightening itself. But that's normal bicycle and especially motorcycle behaviour.

Choice of tire is a factor, and often pressure is a factor. For example, Origin8 Supercell tires are pretty awful at low pressure, but the same tires do almost no self-steering at the max (20 PSI) pressure.

I’m going to rule out user error and weight distribution.

My other bikes with various tire/wheel sizes are not a struggle to operate. “Natural” or “effortless” would be better descriptors.

I weigh a whopping 145lbs, and the bike fits appropriately.

Well, none of us are having this problem with our fat bikes, so what do you chalk it up to?

The tires. I once had Nates that didn’t have this problem. Also Black Floyds that pulled like crazy.

That’s some expensive trial and error there.

Not a problem on all tires, but it is a problem with enough, and the options available have been shrinking. I’d wager a company like Continental would do the R&D to ensure a tire that pulls doesn’t hit the market, but Continental doesn’t even care to be in the shrinking fat bike market anymore.

The fact that it is a problem on some tires and you might be making $250 dice rolls on it is, well, a problem in this market segment.

Also, what kind of unique and special skill set is required of a highly experienced cyclist on a properly fit and well maintained bike? If it really is so highly specialized in the skills required, then that, too, is a problem in this market segment regarding accessibility and long-term viability.

Well, since literally nobody I ride fat-bikes with has this problem the way you do, it is clearly not all that specialized or advance of a skill. Yet you still struggle.

Sounds to me like you may be under-inflating your tires for your conditions.

Well, now we both have anecdotes.

However, fat tire steering issues are certainly known, and a cursory search will reveal numerous anecdotes and discussions on multiple sites.

Additionally, I have run 4 kinds of tires on this bike in the years I’ve had it. 2 had unnerving steering/cornering properties, 2 did not. My “skill level” (cyclocross racer, road racer, recreational MTB-er, long distance rider, and drunken-master urban pub crawler) remained relatively constant between all 4 sets.

So, that’s a 50% rate of unacceptable performance where the only variable that changed appreciably was the tire.

The only way you are going to get self steer is running very low pressure on hard pack surface. That will happen with all tires.

So yes...it's you. Maybe fat bikes aren't for you since you don't know how to operate them and maybe you should move on because nobody else seems to have this problem.

One anecdote is you. The other is everyone else.

Yes, self steer can be an issue if you run the tires too low on hard-pack as stated above.

Most people simply adjust their tire pressure. But I guess whining on the internet is another approach.

Running pressure too low causes issues on any size tires. Smaller tires don’t tend to self steer because you will get rim strikes or wrecked wheels before the pressure gets that low.

Why not get something tried and true like jumbo jims and be done with it..?

Believe it or not, I've had bad experiences with lots of different tire types and sizes. It's almost as if design flaws can happen in any tire type.

Also like many have stated, pump up your tires more. A different casing will require different pressures so if you're just going by arbitrary numbers you're going to have a bad time.

I've got 2 fatbikes - one is my daily driver with more than 2000 km on it, most of that on cheap Kenda k1118s at 30 psi. rolls fast (fatbike fast anyway) and behaves exactly as I expect it to.

I've never experienced the phenomenon you are experiencing. Not even in the winter on Jumbo Jims where I generally ride at 6-9 psi.

Good luck

I can see the heavy tread digging in and reacting to some oversteer. But come on man, it's off road and your hands are on the bars, control your bike, enjoy the fight, take command and ride it. Or sell it and get back on the porch.

On your left and coming around...

Last evening I went out on a 26+ front wheel mountain bike I made up a few years ago. It's not a fat bike. But anyway the front tire is a 26x2.8, tubeless WTB probably Ranger (the rear is 2.35 Maxxis Ikon). Anyway I decided to try riding lower pressure (the tires had outgassed since the last ride), 16psi front and 20 rear ,than usual on both, bucking my regular preference (which is 20psi front and 26 rear), and for the first time on this bike I experienced a minor and controllable yet suboptimal performance overall. Self steer happens with too low a pressure for the conditions. [Still had a great ride and didn't burp even though I did pursue some high velocity descents.]

My theory is that huge volume tires are most sensitive to air pressure variations because there's more air! Bingo bongo. And so fiddling with the precise pressure for performance is more critical than with low volume tires. The upside is that the amount of performance potential is greater. The downside is that the potential for poor performance is also greater than lower volume tires,

For fat bikes riding on hard terrain, ie. most dirt trails and roads, and not riding in deep dust, sand, and various snow conditions, we've got to ride them relatively firm to get some semblance of efficiency and good control no matter what brand, casing, size, and tread. Self-steer is very bad in desdending technical situation because if you cannot predict where you are going -that is the definition of out of control!

That said, then it may be contended that fat-bikes are not good for most mountain bike situations - and I agree. However, there are things I can ride over on my fat bike that I might not even try on my mountain bikes.

There general emphasis on speed in all forms of cycling is not kind to fat biking. The sheer heft of the tires is literally a drag. However, if you throw out the need for speed and replace that with fun, well maybe we've got a benefit there.

Another aspect of the tire and pressure which is critical to the control envelope is rebound. Don't want to go deep on that topic in this thread. But I will say that the rebound effect gets worse with over-pressure. This means that I seek air pressure, riding on dirt (which is where I'm usually riding my fat bike) somewhere above self-steer and below excessive rebound.

I had BAD self-steer with Vee Mission 26x4.0 tires.

I replaced the front with a Kenda Juggernaut Elite 26x4.8, and it was far better behaved, even at much lower pressures. Yes, tires matter. There are crappy tires out there. (Looking at you Vee - Speedster BMX race tires are horrible too)

I mostly ride on snow though, where even the Vee Mission tires were controllable (if still far worse overall than the Kendas). I think many fatbike tires are designed primarily for snow - if you're riding on dirt and they don't act right, that's using them outside of design.