Front wheel/tire flex to the left under braking

Anytime I brake a little hard or turn hard the front wheel and tire flex to the left and the tire rubs the fork, I’ve been trying forever to figure this one out. I’ve had the wheel trued and dished checked. I’ve tried a couple different qr skewers. Sometimes the front wheel will come a bit lose after a while. The bike is a 2012 trance with a suntour xc32 fork. Any ideas are welcome!

Is the hub tight enough? I used to have a similar issue with my 2010 Reign. I was always having to adjust the hub tightness, and I had a heck of a time getting it right. Too loose and it would loosen over time and the wheel would would flex too much, too tight and the wheel wouldn’t spin well enough. I fiddled with it enough that eventually got it. Might not be a bad thing to check.

That fork is also notoriously flexy, so it could just be that and a tire that is a little too wide for it. QR-based forks don’t have a ton of lateral stiffness either.

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Long shot possibility is the wheel is built wrong. If the spoke direction and pattern isn’t correct it can cause this, compare it to an online photo.

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Brace the wheel between your legs facing the bike and try turning the bars, you will probably see the fork flex like an overdone fettucine.

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Could try having someone stand in front of the bike with a smartphone and record slo-mo video as you brake hard to see if you can see what’s going on. Or do the same with a gopro mounted to the handlebar and frame pointed at the wheel and fork.

How long have you had the bike and how long has it been doing this? If it wasn’t doing this when you bought it, has anything changed? New tire? Fork had any service? Wheel hubs overhauled? Had any big hits that might have tweaked the fork?

I assume you or your shop checked for side-to-side play in the hub, which if loose would require adjusting the cones, like @EMat says.

If it’s wheel flex - maybe increasing spoke tension all the way around the wheel? Probably wouldn’t make too much difference without going to stronger spokes?

The simplest solution is to run a smaller tire, or if the outer knobs are rubbing, take a cable cutter, cut down the offending knobs on the tire, and don’t corner too hard.

It has been doing it to some degree most of the time I’ve had it since 2013. It just seems much worse now, could be the tire, although it’s a 2.3 and the Nokia 2.5s I had on there were much better. It’s hard to find a 26in fork to replace it.

Have you tried only turning right?

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Yep. And brakes are for sissies

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Worked for Derek Zoolander and he was a top male model.

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do you know anyone with a QR front wheel that you could try in your fork to see if the same thing happens? If it still happens the problem has to be the fork, if it doesn’t your wheel is the problem. Or maybe the QR is not tight enough- that seems possible since you mention that the wheel sometimes gets loose. It shouldn’t do that.

If you do decide to upgrade the fork I’d suggest getting something with a 15mm or 20mm axle. It will be much stiffer. It does mean you might need a new front wheel unless your hub is convertible.

Odd too that you didn’t experience the problem to the same degree with a wider tire- that’s kind of counterintuitive.

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Qr was definitely tight, tried a couple different ones. I dont have any other 26in disc brake wheels to try on there.

I have a Mavic Crossmax ST front wheel you could try. It should be plenty stiff.

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That would be great! It would cross one more thing off the list potentially

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If the fork is the issue, your bike takes a tapered steerer which does make finding a fork not too bad (versus a straight 1 1/8" steerer) but harder to find with QR dropouts versus a 15mm thru axle. Some of the Giant stuff of that era uses a weird “Overdrive” headset with a 1 1/4 to 1 1/2 instead of the standard 1 1/8 to 1 1/2. Luckily you dodged that one.

Personal message me, and we can arrange for you to pick up the wheel to try it.

Just checked this , I had no idea a fork would flex that much!

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On my 98 SID I could make the brake pads rub by standing up for a climb.

After checking another wheel with smaller tire, it is definitely the fork. It’s a rockshox xc32, not sure why I said suntour. For now I’ll have to find a skinny tire to throw on there and deal with it

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I have that same fork on my commuter. With 29" wheels and 1.5" street tires, I can almost flex it enough to rub the tire on the inside of the fork in a hard turn. The 2.0 Rocket Ralphs that came on it can be pushed into the fork easily.

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