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Old 05-26-11, 09:50 AM   #1
qcx1923
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lowrider pannier position with increased weight

I was wondering how other people position greater weight relative to the front wheel, relative to the axle. Or whether to position a pannier clip behind fork.

The hardware: Tubus Ergo rack on a 62cm LHT. Ortilieb sport packer front panniers. Heavy load. 700c x 37 Continental Contact tires if anyone cares. I am 6'4", size 14 feet and weigh around 225. Over 100lbs of additional gear load on the bike.

The situation: I have toured a fair amount, usually rear panniers only. I recently took 3 of my kids on their first week-long tour. The oldest (11) carried a full load, another a lighter load, and the youngest (8) took almost no load. This left me with 2.5 loads and a weeks worth of food. Relatively flat route wasn't too bad.

I had a lot of shimmy problems that I have never experienced before. I naturally set up the front racks/panniers to position the weight as close to the center of the wheel (axle) as possible. Both clips in front of fork. As a result of the shimmying, I started experimenting a bit with forward and back positions. No major difference. Increasing the tire pressure made more difference.

What is the best/correct/optimal position for front panniers? I notice in pictures that many people seem to angle their front racks forward and down, which would seem to push the weight even farther forward. I assumed this was because of mounting limitations. But is there another reason?
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Old 05-26-11, 09:56 AM   #2
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I could go no hands with this set up. Total gear 56 lbs.

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Old 05-26-11, 10:01 AM   #3
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Yeah, I was wondering about the same thing recently. I had some stability issues too with front panniers. Looking at 10 Wheels picture it seems I put my panniers too far back (towards the center of the bike). I'll have to try moving them and/or the rack more forward.
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Old 05-26-11, 11:20 AM   #4
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What kind of bike? If your bike has very little rake,it can get twitchy with weight on the front of it.The more weight you add the LESS rake it has.This is why touring bikes have alot of rake to begin with.The turning is sluggish without weight but actually inproves with stuff added to the front.

Without getting technical,as you turn the front wheel,it actually lifts the front of the frame up and down.This is caused from the caster angle(rake on a bike).So,if you add weight behind the axle,the weight from panniers actually help keep the front wheel straight.

If the panniers are in front of the axle,it wants to be in the back.

Thus the trying to get the pannier centered on the axle,hopefully a neutral position.

This is the simpleton version of steering geometry,there's lots more involved.

Now all of this is what happens on paper,it's not written in stone.There are so many variables,no two people will have the same experience.But it should help you understand what is going on.

As a side note,if you ever looked close at a bike that they ride in the circus or do tricks on,many of them will have no rake at all.They will have a straight fork,that's so when they do tricks,the wheel does not want to return to center,their weight being swung around the bike doesn't have an effect on the steering.

Remember the old time Harley choppers with the long forks? Really long forks? They can have massive positive caster,ever when the head tube is raked.When you turn one of those,the frame can lift a couple inches! So the weight of the bike wants to keep the front wheel straight.

Positive caster makes the front end twitchy,because the axle in the FRONT of the fork centerline,but it still wants to roll straight ahead.It still has to lift the weight of you and the bike in order to turn.

Negitive caster makes the front end roll straight,but is NOT twitchy because the axle is trailing BEHIND fork centerline.It still has to lift the weight of you and the bike in order to turn.

The more caster angle,positive or negitive,the more the wheel wants to stay straight.The more positive caster,the more twitchy it gets,the more negitive caster,the more stable it gets.

The closer you get to neutral rake,the less the effect of outside sources,but you sacrifice stability going straight.If you cross the line with positive caster,stability goes out the window.

Basically,it works like a giant front wheel on a shopping cart.

Last edited by Booger1; 05-26-11 at 12:50 PM.
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