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mhelander
recumbent enthusiast

Finland
257 Posts
Posted - 05/20/2012 :  13:02:44  Show Profile  Reply with Quote
In short: I have not so pleasant problem while riding my two bents : over time my torso appears to shift in my hard seats to left. My right leg starts touching to main frame tube and because of shifted weight that has impact to handling.

Why that matters: in my yesterday's 130 km leg, riding my lowracer, my constant re-positioning of torso caused soreness above my right knee.

Little history: soon after introducing to bents in 2010 riding lowracer I noticed this torso shifting. Last fall I thought my left leg is shorter and tried double additional insoles (some 3-5 mm) below left shoe's one and that didn't fix torso shifting but caused, again, soreness in right knee area.

And when I poked my memory I had same kind of issues while riding Tri-TT in -90's : my right leg was kind of scrubbing more seat and torso was little shifted to left.

Because of this, and to keep handling of my bents as designed, my wheels are perfectly round and true, aligned to perfectly up and in-line. Same applies to tiller steering arms and seats are too exactly level. When I start riding either (another is MetaPhysic, both are tuned to same rider's geometry) everything is OK, body and weight is in center and handling ok. And then after a while when pedaled I notice my right leg touches main frame tube...

I'm using SPD-SL pedals which have zero float (I like that this way, SPD's are causing more problems to leg muscles and knee area). This autumn I measured carefully my foot dimensions and re-positioned cleats per foot to as low as possible bo exactly relative to ball of foot. That didn't help in torso shifting. I've aligned both shoes to same position in relation to their crankarms.

I've researched little about topic of general bike fitting and in world of uprights in some cases using wedges between cleat and shoe mis-alignments are corrected. Would use professionals of this area but in my city none exists (that I'm aware of).

Anyone any advises how to proceed/diagnose/fix this problem ?

Cheers,
-Mika

MetaPhysic 700c @ 2011, M5 CrMo Lowracer @ 2010

harv
recumbent enthusiast

317 Posts
Posted - 05/20/2012 :  13:11:29  Show Profile  Reply with Quote
A couple of complete SWAGs. Adjust your left rear view mirror so you don't have to shift your head to use it, or put a roll of quarters in your right shirt pocket to act as a counter balance. :)
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mhelander
recumbent enthusiast

Finland
257 Posts
Posted - 05/21/2012 :  01:50:46  Show Profile  Reply with Quote
Heh... I have mirror in my helmet (Zefal Z-Eye) and it is easy to adjust so that no head movement is needed...

And this counter weight is been executed alredy in MetaPhysic, as I don't have bottle holder so fabricated from scrap carbon plate to mount it to right side of seat. That adds 650 g water (+ bottle & holder) weight to right side.

Q is different in my bents, lowracer has 112mm Campy square bore BB and old Record crankset, Meta has GXP which is about 2cm wider. Lowracer feels better as does its copied VeloKraft seat.

I'm likely trying next to re-check my shoe alignments related to pedals, and starting from left shoe rotate it counter clock-wise. If that works, even partially, I'll do same for right shoe.

Shimming/wedging try outs I'll delay till first "race" is over.

Cheers,
-Mika

MetaPhysic 700c @ 2011, M5 CrMo Lowracer @ 2010
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revbsg
New Member

57 Posts
Posted - 05/21/2012 :  04:15:48  Show Profile  Reply with Quote
I suffer from a similar problem. I found using a pedal extender on one pedal, but not the other, helped a lot, but did not completely cure the problem.

Godspeed,
Pop
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mhelander
recumbent enthusiast

Finland
257 Posts
Posted - 05/21/2012 :  04:36:39  Show Profile  Reply with Quote
Yeah, it also might be caused by differences in leg muscles... in my case right leg is stronger and thus when pedaling is pushing torso to left.

But this problem is worse when riding in mediate power, like my 140 HR average over most of my legs. Torso stays better in center when pushing really hard, or climbing 8+ % inclines.

My additional insoles in left shoe was my 1st try. Now it might be best to try to rotate left shoe counter clock-wise and do some left leg only power intervals to get used to new alignment and strengthen left leg muscles.

Cheers,
-Mika

MetaPhysic 700c @ 2011, M5 CrMo Lowracer @ 2010
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warren
human power expert

4230 Posts
Posted - 05/21/2012 :  06:12:10  Show Profile  Visit warren's Homepage  Reply with Quote
Try pedaling with just the left leg for a while during each ride.

Also they make special cranks that allow each leg to pedal independently. you have to try hard to keep the cranks 180 degrees apart. That would be a good way to train your legs to push the same amount.

-Warren.
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purplepeopledesign
recumbent guru

Canada
568 Posts
Posted - 05/21/2012 :  10:40:02  Show Profile  Reply with Quote
How about those friction mats that are used for shelves, toolboxes, rugs and sofa cushions?

:)ensen


Those who claim to be making history are often the same ones repeating it.

Video of my trike
http://www.youtube.com/watch?v=MdSLRD_2vzc
Photos of my trike
http://www.flickr.com/photos/purplepeople/
Edited by - purplepeopledesign on 05/21/2012 10:40:26
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mhelander
recumbent enthusiast

Finland
257 Posts
Posted - 05/21/2012 :  12:01:05  Show Profile  Reply with Quote
Ensen, your hint has some idea... as I forgot to mention that my hard seats are topped with Ventisit standard cushion. If wearing lycra kind of pants it's quite slippery.

But still, this is not so about friction to keep body position in seat, it's more about pedaling to bump and step by step move my torso to left.

I have some of that matrix under mat friction adder thingy, might try that between butt and Ventisit. Could be useful after those minor adjustment and during left leg training.

Cheers,
-Mika

MetaPhysic 700c @ 2011, M5 CrMo Lowracer @ 2010
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kidneyboy
Starting Member

USA
24 Posts
Posted - 05/22/2012 :  04:35:27  Show Profile  Reply with Quote
Mika, I have the same issue. My chiropractor has suggested it is a strutural issue, having to do with years of being a stonemason amomg other things.I am right handed and my right leg is just a little longer than left. We fixed it on my road bike by sliding my body forward a bit so my knees were forward of the center of the pedals. I didn't have this problem with any of my LWB, mesh seat bents but it showed up again on my Volae Tour and now the Silvio. I never figured it out with the Volae but thought I would try adjusting cleat placement on my right shoe (cleats are all the way back now) and a slight bit of padding, 1/8" to 1/4", on the left side of the back of the seat (lower lumbar area). I'll report back with any results.

chuck
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mhelander
recumbent enthusiast

Finland
257 Posts
Posted - 05/22/2012 :  05:10:07  Show Profile  Reply with Quote
Good to know I'm not alone...

Here are pictures of me riding lowracer (just starting that 130 km leg @ Saturday):





Too bad that in front view I'm not fully clipped in, but my torso is very near center of the seat and wheels etc are perfectly aligned.

I'll try my right knee area today does it allow pedaling and if so tomorrow will be 75 km + 80 km riding day. Time to execute my plan and do some corrective one legged training along the way...

Cheers,
-Mika

MetaPhysic 700c @ 2011, M5 CrMo Lowracer @ 2010
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Speedbiker
human power supergeek

USA
1995 Posts
Posted - 05/22/2012 :  05:53:45  Show Profile  Reply with Quote
Notice the Finland summer riding kit and the self-made eliptical chainring :-)
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mhelander
recumbent enthusiast

Finland
257 Posts
Posted - 05/22/2012 :  06:11:12  Show Profile  Reply with Quote
quote:
Originally posted by Speedbiker

Notice the Finland summer riding kit and the self-made eliptical chainring :-)


Finnish summer (?) eh... we've yet to see warm weathers. This leg started in gusty winds and +13 C, warmest was about 20 but then turned to 8 with rain.

Only thing I adjusted in my clothing was removing of helmet cap and clubs when in 20 C zone and put those back later. This fitting works from +2 to +15 adequately when training. This high-viz doesn't keep pouring rain out unfortunately.

When it goes below freezing I'll add wind stopper running pants on top and shoe warmers, put on cold weather riding jacket topped with fully wind and water proof high-viz vest, and add 1-3 balaclavas and warmer clubs. Did ride my 1st MUP leg last fall with such dressing riding exactly this same bike (and tires), in -9 C.

Cheers,
-Mika

MetaPhysic 700c @ 2011, M5 CrMo Lowracer @ 2010
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mhelander
recumbent enthusiast

Finland
257 Posts
Posted - 05/22/2012 :  06:12:58  Show Profile  Reply with Quote
quote:
Originally posted by Speedbiker

Notice the Finland summer riding kit and the self-made eliptical chainring :-)


And if looking very carefully you can see, in addition to vintage Campy Record crankarms, that I'm having -90's Campy Record braze on FD. Those are last old parts I'm using in my bents now... rest are waiting some upcoming projects...

Cheers,
-Mika

MetaPhysic 700c @ 2011, M5 CrMo Lowracer @ 2010
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Runxner
recumbent enthusiast

Australia
327 Posts
Posted - 05/22/2012 :  06:47:11  Show Profile  Reply with Quote
Pedal faster, more G's. Are the roads\paths crowned(for drainage)? Same thing happen ridding the other side? Do you make more right turn than left on your routes? Frame alignment? Single sided fork straight? Tires worn symetricly. Are the roads bumpy enough to bounce off the seat?

Team Low-Life
Lowracer Test Pilot/Evangelist
Adelaide, Australia
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mhelander
recumbent enthusiast

Finland
257 Posts
Posted - 05/22/2012 :  07:35:33  Show Profile  Reply with Quote
quote:
Originally posted by Runxner

Pedal faster, more G's. Are the roads\paths crowned(for drainage)? Same thing happen ridding the other side? Do you make more right turn than left on your routes? Frame alignment? Single sided fork straight? Tires worn symetricly. Are the roads bumpy enough to bounce off the seat?


Trying to pedal faster, all the times :)

Yes, our roads must be designed to drain water out to prevent frozen ground to destroy them. I noticed when putting last season's Durano 451 to front that it has about 10mm wide flat wear pattern, and that was almost perfectly horizontal. It lasted without punctures only some 4000+ km's and is still good spare tire.

No, I don't recall having any difference in my courses per turning more left or right, as I do vary my legs as much as possible. What's related to micro-steering while pedaling might be another issue but I'm practicing to ride very straight and smooth line anyways, excluding steep uphills.

Frame alignment is perfect in both bikes. And both bikes got fresh tires couple of weeks ago. Also M5 monofork is solid and front wheel straight (rebuild for that 130 km leg). These were my 1st to check and I'm constantly monitoring overall trueness of my bents.

Our roads, at least ones I like to ride, are not that bouncy. But tarmac surface varies from silk smooth to almost gravel. M5 with Ventisit is comfortable enough then and MetaPhysic has carbon suspension spring between seat and seat stays which helps a lot.

Cheers,
-Mika

MetaPhysic 700c @ 2011, M5 CrMo Lowracer @ 2010
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Speedbiker
human power supergeek

USA
1995 Posts
Posted - 05/22/2012 :  08:07:20  Show Profile  Reply with Quote
How about velco jersey and seat pad?

:-)
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mhelander
recumbent enthusiast

Finland
257 Posts
Posted - 05/22/2012 :  13:32:01  Show Profile  Reply with Quote
quote:
Originally posted by mhelander

Now it might be best to try to rotate left shoe counter clock-wise and do some left leg only power intervals to get used to new alignment and strengthen left leg muscles.


Ok, some progress. Took lowracer and measured all relevant issues. Seat is perfectly level. So are tires in single track and straight. Tiller was off (in handlebar position) couple of mm's so that's fixed, also neck rest was loose and is tightened.

Then boom... measuring crankarms to be perfectly vertical was hard, as I have vintage Campy cranks and arms are not in 90 degree from BB axle, and not both as much off.

So put bike to perfect vertical position and then adjusted boom so that BB tube is perfectly horizontal.

Next adjusted left cleat to get ankle more to boom side. And then test riding this setup to recovery leg...

Riding felt better, torso seems to stay better in place, even when pedaling without much power. As I entered to one of nearby 10 km TT leg, wind was calming down so time to put little more effort... and riding was even better in almost racing level.

After sauna checked my Edge's recordings and I did TT below 15 minutes, first time since mid-90's and riding bent !

This seems to be working method, next longer leg will reveal more I think.

Cheers,
-Mika

MetaPhysic 700c @ 2011, M5 CrMo Lowracer @ 2010
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Speedbiker
human power supergeek

USA
1995 Posts
Posted - 05/22/2012 :  15:37:46  Show Profile  Reply with Quote
40k/hour +!
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mhelander
recumbent enthusiast

Finland
257 Posts
Posted - 05/22/2012 :  23:47:55  Show Profile  Reply with Quote
quote:
Originally posted by Speedbiker

40k/hour +!


Yes. With this average HR (158) I can easily maintain 40 kph under hour in not too windy local condition.

This means "I'm back" in business...

Cheers,
-Mika

MetaPhysic 700c @ 2011, M5 CrMo Lowracer @ 2010
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Speedbiker
human power supergeek

USA
1995 Posts
Posted - 05/23/2012 :  06:26:20  Show Profile  Reply with Quote
40k/hr in a loose jacket, non aero helmet, and high drag mustache. I can't wait to see your race results after you go full aero!
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mhelander
recumbent enthusiast

Finland
257 Posts
Posted - 05/23/2012 :  14:11:22  Show Profile  Reply with Quote
quote:
Originally posted by Speedbiker

40k/hr in a loose jacket, non aero helmet, and high drag mustache. I can't wait to see your race results after you go full aero!


One or two of those will stay. I'll target to break my own old records first. Then attack to other records...

Btw, our local recumbent race is nominated to be national championship race. Rules according to WRRA. No much streamlines, couple velomobiles expected.

1st day speed measured in 200m gates, then hour race. 2nd day 12h distance race. I'll likely participate all of those.

And back to subject, had today 150 km easy leg riding MetaPhysic. Did same adjustments to it as did for lowracer. It's worse to ride, torso shifts pretty much all times to left. Also seems that my legs doesn't extend as much with it than in lowracer, interesting...

I likely need to rotate left shoe even more counter clock-wise to get my power vectors right. And glue for good velcro to VeloKraft seat... it doesn't hold. And use that rubber friction net to keep Ventisit in place.

Didn't help that about half of that distance there was rumble strip in right from white side marking, and then in worst places only 10"/20cm pavement... slipped out from it couple of times and then went sideways when returning. Had to change strategy and ride over rumble to road side in narrowest places. Much more relaxed riding for rest of the leg.


Cheers,
-Mika

MetaPhysic 700c @ 2011, M5 CrMo Lowracer @ 2010
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