Author Topic: stability  (Read 1452 times)

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Offline Max!

stability
« on: June 12, 2013, 06:55:38 pm »
So I just completed my first multi- day self supported tour with a full camping setup and am looking for some advice. During big long descents i didn't have as much stability as i would have liked and am wondering if i should either a) use front panniers or b) get wider tires. To be clear, descents were still fun and I probably got going around 40mph, I just would like a little more stability.

Background: I have a surly crosscheck with 25c panaracer pasella tg tires and am only using a full size set of ortlieb rear panniers. My handlebars are pretty high for an fairly upright riding style. I weigh about 135, fully loaded bike was 50lb (roughly 30lb bike and 20lb panniers and gear). I can't imagine carrying more than I was on this trip.

All advice is welcomed.

Offline dkoloko

Re: stability
« Reply #1 on: June 12, 2013, 07:25:15 pm »
Need more information on what concerns you had as to "stability" on descents. Bike shaking? what? Bike, itself, as differentiated from tires, no problem? Headset correctly adjusted?

Offline Max!

Re: stability
« Reply #2 on: June 12, 2013, 07:30:45 pm »
Stability, well I found myself not being able to go as fast as I would have liked with sideways wind gusts.  The headset was freshly adjusted by my lbs and seems good. No shaking or shimmying just me trying to stay upright on big windy hills!

Offline adventurepdx

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Re: stability
« Reply #3 on: June 13, 2013, 03:35:30 am »
Stability, well I found myself not being able to go as fast as I would have liked with sideways wind gusts.

I'm no expert, but I think you found your problem there. Crosswinds are always a pain and there's not much you can do about it. I still would recommend wider tires, maybe 28-32mm at least.

Offline DaveB

Re: stability
« Reply #4 on: June 13, 2013, 07:58:02 pm »
Stability, well I found myself not being able to go as fast as I would have liked with sideways wind gusts.
That's not instability, that's normal.  Gusty sidewinds always make a bike harder to control and the faster you are going, the greater the effect.

Offline Max!

Re: stability
« Reply #5 on: June 13, 2013, 08:18:52 pm »
OK, well. . . I'll resign myself to going a little slower than I like in those conditions and I'll look at getting some 28c tires for giggles.

Offline DanE

Re: stability
« Reply #6 on: June 14, 2013, 06:25:38 am »
Side winds will definitely push you around and they aren't going anywhere. However, stability has a lot to do with weight distribution on the bicycle. This includes the weight distribution of yourself as well as your gear.

Front panniers can help quite a bit as they take some of that weight that is on the back and put in on the front. This can help quite a bit, but might not be too beneficial if you just add front panniers then fill them up with more stuff to carry and still carry the same amount on the rear. I like to use two sets of front panniers, mounted on the front and rear. That way I have no extra capacity really so I avoid the temptation to carry more stuff but I have redistributed the weight over the front and rear. This works well for short, week long trips or less. It's probably not going to work for your epic tours and you will just have to take the large rear panniers and try to control yourself with what you carry.

Your positioning on the bike during descents is probably bigger effect than how your panniers are packed. I try to keep my body weight in what I call "inside the triangle" as I descend. What I mean by this is to keep your weight distributed inside the main triangle of the bike and not loading the back of the bike by hanging your butt off the back of the saddle. Slide forward on the saddle and bring your weight over the bottom bracket and stand on the pedals, weight off the saddle as much as you can. Your butt might not even have any weight on the saddle.

Get your hands in the drops and get your upper body pressing down into the handlebars, your arms should be pushing forward putting pressure on the handlebars. Place a knee against the top tube of the bike, this will help dampen any excessive vibrations in the bike frame. Keep your body relaxed as this will absorb the shocks of the bumps.

Lowering your handlebars will usually make a bicycle more stable. It makes it easier to get your body weight forward if they are in a lower position. If you drop your shoulders low enough you will feel the wind shift off your chest and begin to flow over your shoulders, this makes it feel like there is less wind pushing you around.

Look far down the road as you descend, then it looks like things are not coming up at you quite as fast as if you are just looking down the road a few feet. Try to relax and put your mind in it's peaceful place. Wider tires than what you are running would be better for a loaded touring bicycle.

Offline John Nelson

Re: stability
« Reply #7 on: June 16, 2013, 06:53:37 pm »
Post back if you still have stability problems on a calm wind day. If so, then something else is going on and we should discuss further.

Offline DU

Re: stability
« Reply #8 on: June 17, 2013, 09:16:23 am »
I think a bike with panniers simply catches a lot more wind, side winds or otherwise. On the same downhills, I have gone considerably slower on a loaded touring bike (front and rear panniers) compared an unloaded bike. I imagine the 40 spoke wheels with fenders on my touring bike added to the wind resistance, making the bike even slower.

Offline dkoloko

Re: stability
« Reply #9 on: June 17, 2013, 11:40:48 am »
Post back if you still have stability problems on a calm wind day. If so, then something else is going on and we should discuss further.

Good thought.

Offline Max!

Re: stability
« Reply #10 on: June 17, 2013, 12:34:35 pm »
Thanks everyone for your feedback.  This is a pretty minor issue. . . if I just go a little slower than I would like I'm fine, and I think I am fine on descents without side-winds.  I have a ton of shorter steep hills in my area. . . I'll try to force myself to ride loaded down a few of them in low wind conditions and maybe try a different set-up with only front bags and see how that all goes.