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General Category >> Technical >> weight distribution and steering
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Message started by Mizta_Nice on Nov 4^th, 2012, 9:12pm

Title: weight distribution and steering
Post by Mizta_Nice on Nov 4^th, 2012, 9:12pm

I am still messing with the position on my new Strada, and I have been leaning the seat into more and more of a reclined position. This weekend, after getting it pretty set where I wanted it, I have noticed the bike is getting hard to control, so much so that I almost lost it several times on the Trinity Trails where it goes from pavement to gravel.

It doesn't seem like I am that laid back, the top of my brain box bag is level with the ground and I've seen others that are much more horizontal than I am. I thought the whole idea was to get laid back to capitalize on the aero advantage.

I was wondering if there is a fix for this problem, or do I need to get more vertical?

Title: Re: weight distribution and steering
Post by Bud_Bent on Nov 4^th, 2012, 10:03pm

Our entire balance system is intended to work with us being vertical, not horizontal. Most of us are able to eventually improve our balance in a near horizontal position, but for many of us, it does take some time. You may want to raise the seat back up a bit, then try reclining it more again after you get more miles on the bike.

The other thing I would say is don't hesitate to sit up for a few seconds if you need to for a slow speed, tricky maneuver. I still do that occasionally, myself.

Title: Re: weight distribution and steering
Post by FlyingLaZBoy on Nov 5^th, 2012, 7:47am

Agreed -- which is why a more upright seating position makes the EZ-1 and others a lot easier for a beginner. You're not only more reclined, your feet are up a lot higher, so your whole center of gravity is different. The "laid back" seat style typically doesn't work well for more upright positions - not enough padding for the rear end. Ride at a particular recline that suits you for several times out, as you learn the handling... as long as you're not having tailbone issues from sitting too upright. Then try lowering it one notch.

When you want to change to more recline, shift one pin position, move the seat clamp forward about 1/4", and ride like that for a while, to allow your neck to adjust. Whenever you change the recline, you should tinker with the fore/aft position as well, in small increments -- you don't want to feel like you're having to "reach" for the pedals at furthest extension. Typically, when you recline more, move the seat forward, and the opposite when you recline less.

I typically have my Xstream 'hoagie' seat in the next to last pin hole -- but occasionally set it to the last hole setting (especially on a windy day), and can feel the change.

There's also the tradeoff between recline and climbing power, typically. If you get TOO reclined, you tend to lose seatback support when putting power to the pedals. So it's going to be your individual setting preference, especially since you DO have some back issues...

Take a picture and post it, showing how you've got it set up.

And remember, watch that heelstrike when trying to do a sharp turn!!!

Paul

Title: Re: weight distribution and steering
Post by rmillay on Nov 5^th, 2012, 3:52pm

Our bikes range from almost even weight distribution to high racers with mote weight on the front wheel, to long wheelbase models, which may have over 70% of the weight on the rear wheel. We ride them all, so clearly it's more about learning the bike's handling characteristics than inherent problems with weight distribution. It does help to know how much pressure each tire needs for your bike, though. Bud and Paul are right about gradually adjusting your seat recline. I found the same effect when I tried adjusting my Formula's seat; too much change was disorienting.

Title: Re: weight distribution and steering
Post by Mizta_Nice on Nov 10^th, 2012, 12:46pm

I agree with all of your advice, but i feel like it's not a balance issue since I have had this happen on my other bikes. I find that if I get too far back on the frame, where my shoulders are at or behind the rear hub, then the bike's handling changes dramatically. The only way to describe it, is to say that the rear wheel feels like it's "kicking out" to the side as i pedal. If I apply power to the right pedal as I hit a patch of gravel or dirt, then the rear wheel jumps to the left suddenly in the dirt making the bike uncontrollable.

I've done searches on the web and found others with the same issue. I think the bike may need to be a frame size larger to all ow me to recline without this happening. [smiley=shrug.gif]

I will post a pic to show what I mean in a few.

Title: Re: weight distribution and steering
Post by FlyingLaZBoy on Nov 10^th, 2012, 3:44pm

Mizta_Nice wrote:

IThe only way to describe it, is to say that the rear wheel feels like it's "kicking out" to the side as i pedal. If I apply power to the right pedal as I hit a patch of gravel or dirt, then the rear wheel jumps to the left suddenly in the dirt making the bike uncontrollable.

Title: Re: weight distribution and steering
Post by Mizta_Nice on Nov 12^th, 2012, 3:19pm

FlyingLaZBoy wrote:

[quote author=Mizta_Nice link=1352085122/0#4 date=1352573175]IThe only way to describe it, is to say that the rear wheel feels like it's "kicking out" to the side as i pedal. If I apply power to the right pedal as I hit a patch of gravel or dirt, then the rear wheel jumps to the left suddenly in the dirt making the bike uncontrollable.

Dude, didn't you learn anything from that road rash last month? You're not SUPPOSED to apply power when you're turning in gravel or dirt(!!!) ... unless I'm misunderstanding what you're describing...

However, simply applying power when you're traveling in a straight line should not make the rear wheel slip to the side -- especially if you're further back than you feel you should be, because that only serves to increase the weight load on the rear wheel...

Sumpin's not right...
[/quote]

You're right, I did learn my lesson after my last incident. If I see a change in surface or water on the road, I stop pedaling altogether and just roll forward until I get the situation scoped out. No, this happens when going in a straight line. I need an experts eye on this.

Title: Re: weight distribution and steering
Post by Mizta_Nice on Nov 21^st, 2012, 3:46pm

okay, there was somewhat of a resolution to my problem.

I have made several small adjustments to my riding position over the past few weeks, finally moving the seat forward about an inch from where I had it during the Turkey Roll. Bingo! Everything is great again, and I'm not exactly sure why. My guess is that I am getting more reclined, like I should be, but with more of the weight on the frame of the bike instead of on the rear axle.

Finally!

Title: Re: weight distribution and steering
Post by FlyingLaZBoy on Nov 22^nd, 2012, 5:50pm

As you recline, the seat position typically needs to move forward slightly - because you're moving your hip joint backwards. There's a fine line between overextending and not having enough leg extension -- once you're at the recline you like, make 1/4" changes in the seatclamp position until things feel "right"... You may feel the difference more when climbing, especially if you're too far to the back.