Test riding a true racing recumbent

[3bs]

yeah i have seen that squishy one. not my choice at all. that is why the Chesapeake foam is so good.

https://www.clcboats.com/modules/ca...yak-seats-foam&code=minicell-closed-cell-foam

that is the foam i make my wedges out of so easy to shape too if you want more than just a flat surface.

also, dont just look at the yoga mat at the stores also look at exercise mats. our dunhams has about 10 different thicknesses and densities.

 

[Osiris]

Chain guard or catcher for 1x

https://www.aero-coach.co.uk/store/product/aerocoach-affix-1x-aero-chain-guide

No way to mount one of those to the M5, unfortunately. A local sign shop can cut a 9.5" diam. disk out of aluminum or plastic that should do the job. It will bolt on to the big ring, just like the one JM designed for my M1.

I've also located a fabricator that specializes is 3-D printing. They charge $6 per cubic inch for ABS plastic, so that isn't the right application for making something as simple as a disk shaped chain guard, but they can also print in other materials like steel, aluminum, and carbon fiber. The carbon fiber option really interests me. They charge $12 per cubic inch for CF, but that might be an attractive option for my custom aero handlebar, which has a volume of 2.33 cubic inches.

 

[Osiris]

yeah i have seen that squishy one. not my choice at all. that is why the Chesapeake foam is so good.

https://www.clcboats.com/modules/ca...yak-seats-foam&code=minicell-closed-cell-foam

that is the foam i make my wedges out of so easy to shape too if you want more than just a flat surface.

That foam looks quite solid in the photo, like Styrofoam. Does it compress at all?

 

[tiltmaniac]

No way to mount one of those to the M5, unfortunately. A local sign shop can cut a 9.5" diam. disk out of aluminum or plastic that should do the job. It will bolt on to the big ring, just like the one JM designed for my M1.

I've also located a fabricator that specializes is 3-D printing. They charge $6 per cubic inch for ABS plastic, so that isn't the right application for making something as simple as a disk shaped chain guard, but they can also print in other materials like steel, aluminum, and carbon fiber. The carbon fiber option really interests me. They charge $12 per cubic inch for CF, but that might be an attractive option for my custom aero handlebar, which has a volume of 2.33 cubic inches.

Low-temp moldable plastic considered?

 

[Osiris]

Low-temp moldable plastic considered?

I don't know if they offer that option. I'll be touring their facility this weekend, so I'll have a much better idea then about their capabilities. They have a number of engineers on staff, so they can best advise me as to which materials would be best suited for each application.

 

[ed72]

No way to mount one of those to the M5, unfortunately. A local sign shop can cut a 9.5" diam. disk out of aluminum or plastic that should do the job. It will bolt on to the big ring, just like the one JM designed for my M1.

I've also located a fabricator that specializes is 3-D printing. They charge $6 per cubic inch for ABS plastic, so that isn't the right application for making something as simple as a disk shaped chain guard, but they can also print in other materials like steel, aluminum, and carbon fiber. The carbon fiber option really interests me. They charge $12 per cubic inch for CF, but that might be an attractive option for my custom aero handlebar, which has a volume of 2.33 cubic inches.

You must have a clamp on FD. I have a braze on FD attached to a clamp on the stump. It should work for me

 

[Osiris]

You must have a clamp on FD. I have a braze on FD attached to a clamp on the stump. It should work for me

Yep, I had to buy the ring clamp separately. That meant another week's delay so instead I just rode around for a while without a FD, which worked fine.

 

[3bs]

Yes. It is a touch firmer than the standard m5 pad,I which is just fine with me as those pads bottom out over time. On my different run different variations of these pads we are talking about, and sometimes I also run a ventisit.

 

[Osiris]

Well, it looks like 3-D printing is a bust. It seems this technology is still very, very far from being an affordable alternative to other methods of manufacturing. For example, yesterday I was quoted a price of $6 per cubic inch for plastic parts, so I sent them a computer model of a plastic headlight/camera mount for my V20 in a ready to print format. The total volume of the part is only 0.45 cubic inches, so the cost should have been no higher than $2.70. Imagine my surprise when the quote came in at a whopping $48.68! A larger part I'd sent them earlier in the day would cost a staggering $265 to print. Ridiculous.

 

[3bs]

3d is so attractive but not yet affordable.
I still make most of my small parts out of aluminum and Plastics. Between the hardware stores, the craft stores, Amazon, and my junk piles in my shop, I can fabricate a lot of stuff.

I really need to learn carbon fiber and relearn how precision weld.....and of course become independently wealthy so I can quit my day job and turn my ideas into things.

 

[Osiris]

I'm trying to up my power by 25 watts, lower my CdA by about 10-15 watts, and lose some more weight. 24 mph on 140-150 watts on the flats in warm weather on good roads is my goal.

I'll be following your progress with those bar quite keenly.

I've been waiting for what seems like forever to get the opportunity to do some speed/power testing on a flat road with absolutely no wind. That opportunity finally came for a brief period on Saturday when the air at my favorite trail was absolutely still. The Strava segment I use for much of my testing is 2.12 miles long, starting at 59 feet above sea level which remains level almost all the way to the end. That's about as close to perfectly flat as I've been able to find anywhere. I got a result of 26.7 mph @ 238 watts. That wouldn't be impressive at all on the M1, but it's pretty respectable for my M5, which typically runs ~ 2 mph slower at the same power outputs.

The difficulty of getting reliable data became clear on another segment where the wind had picked up just enough to be noticeable. On this mile long segment, my result was 27.0 mph @ 217 watts. If I hadn't ridden past strips of tape tied to the telephone poles lining the trail, I wouldn't even have been aware that there was a tailwind. In future I might have to ride in opposite directions, paying close attention to my power output just to make certain that even a slight amount of wind isn't influencing my results.

 

[ed72]

3-4 mph is barely noticeable to the eye but has a pretty big effect at 25+ mph.

I have a 12 mile stretch along a river that has some ups and downs. I do my 10 mile TT there (as does USA Cycling).

If I am testing on the road, I tend to do a stretch in one direction (maybe 5 miles) and turn around. Then, I swap gear (like a helmet) and repeat. Four iterations usually gives me a good sense.

I was doing Sweetspot on Saturday going up river. I averaged 251 watts at 27.1 mph......2nd place on Strava. There could have been some wind, but I could not detect it. A State Champ TT is next weekend.....I am going to put some ribbon streamers off the back of my bent and ding my bell while passing them all saying, "lovely morning for a ride, have a nice day....."

I bought some barends to see if I like gunner bars. I have an ash tree in the back of my property. Going to use some of that wood for the bar to test. Now, that is nature's true carbon fibre.

 

[Osiris]

3-4 mph is barely noticeable to the eye but has a pretty big effect at 25+ mph.

I have a 12 mile stretch along a river that has some ups and downs. I do my 10 mile TT there (as does USA Cycling).

If I am testing on the road, I tend to do a stretch in one direction (maybe 5 miles) and turn around. Then, I swap gear (like a helmet) and repeat. Four iterations usually gives me a good sense.

One thing I've been really curious about is how much of an effect wind has on my speed. My impression is that a headwind hurts my speed to a significantly greater extent than a tailwind of equal velocity helps it, but I haven't found a good way to test that theory. It may require a device to accurately measure wind velocity, but I haven't looked into buying one.

I was doing Sweetspot on Saturday going up river. I averaged 251 watts at 27.1 mph......2nd place on Strava. There could have been some wind, but I could not detect it.

How is your M5 equipped? I imagine you've got a full disk wheel in back and a deep section front wheel? Have you experimented with different head angles? I'm going to mount my Zipp 808 on the front and see if helps without making the steering unmanageable in heavy crosswinds. I'm running out of mods to make the M5 faster, although I'm still looking into the possibility of ditching that clunky FD. The very idea that I may be wasting 2-3 watts due to drag is intolerable.

I bought some barends to see if I like gunner bars. I have an ash tree in the back of my property. Going to use some of that wood for the bar to test. Now, that is nature's true carbon fibre.

I think you'll love the gunner bar arrangement. You can buy a 3/4" diam. piece of aluminum tubing from Ace Hardware at very little cost. The nice thing about using that as the cross-bar is that it allows you to slide the bar ends in or out until you find the ideal hand position. You can even take an Allen wrench with you on the ride to make adjustments on the fly. I see Kent P. has made his own version of them: http://synthetictransport.com/barends/index.html

 

[ed72]

In calm conditions, cigar smoke drifts up. At 3 mph, leaves at the top of trees move a little. That is the limit of when I test seriously. Once movement shows on little branches, too much wind for any decent testing unless runs go one direction and back the other multiple times. I average runs out.

I have an Aerocover on the rear and either the Flo60 or M5 2-spoke up front. 25 mm GP5000 rear and 23 mm front on the 2-spoke. I have a box on the back to hold my water bladder and rain gear, it helps in headwind but hurts on sidewind. 2-Spoke is a bit faster in calm conditions but much faster in crosswinds-hands down.

Head angles? The bottom of the headtube was cut off by Bram. I am going to try another fork, the Ridley version of the A911 that is like two forks.

I am using the Thor seat, it catches more wind at the thigh area but the improved shoulder support and overall comfort keeps it on the bike. I have lost some weight and have been thinking of trying the stock seat again. Just a PITA to swap out. I also have 3 inch wide electrical tape between the seat edge and the M5 carbon frame. It keeps water out and seems to help stability in cross wind, which was my main purpose. I had been experimenting with seat angle, tailbox height, rims, etc. to improve high speed stability in gusty crosswinds. I am much better, part of it is just having the guts to ride in very windy conditions and then normal windy conditions seem easy. I have a Rotor RS4x crankset *dirty* aerodynamics with 56 teeth.

Thanks for the Alu bar recommendation. I could also cut down my circa 1987 Greg Lemond TT clip-ons but they are probably worth money...

 

[Osiris]

Head angles? The bottom of the headtube was cut off by Bram. I am going to try another fork, the Ridley version of the A911 that is like two forks.

Sorry about the imprecise language. I was actually referring to the rider's head angle. I've been experimenting with different headrests to see if a greater angle of recline translates into better speed, but I haven't seen it yet. Part of the problem may be my helmet. With my head in a more upright position, wind flows smoothly around the visor, but at a greater angle of recline, air rushes into the gap between the bottom of the visor and my face.

As far as wheels go, I seem to remember one local TT racer using tape to cover the gap between the edge of the rim and the tire to create a perfectly smooth transition. I don't know how much it added to his speed, but IIRC, it was considered a rule violation.

 

[ed72]

Sorry about the imprecise language. I was actually referring to the rider's head angle. I've been experimenting with different headrests to see if a greater angle of recline translates into better speed, but I haven't seen it yet. Part of the problem may be my helmet. With my head in a more upright position, wind flows smoothly around the visor, but at a greater angle of recline, air rushes into the gap between the bottom of the visor and my face.

I have not rigorously tested but a more reclined neck angle puts my chin closer to my chest AND more significantly aids breathing. Now, you might find the opposite WRT to breathing. I have a screwed up neck. Informally, it seems to also lower the elevation of my head and seems faster. I do nonetheless intend to do testing on face shield vs just glasses. I lost one of the Vanquish shields and it is like $60 for replacement. I have the clear one still (evening riding) but I am not sure it is faster and if not, why spend money on it. I spray paint the top of the shield in white to block the sun. I do it right at the horizon level.

My knee at the top is right about the height of the top of my helmet, so, I doubt going lower on the seat would earn me much and probably cost me power. If I went to 145 mm cranks from 175 mm, I suppose lowering the seat could gain me on frontal area. I think my midsole cleated 48 mega shoe is an even bigger issue....it seems higher than my knee. There is a reason all the fast riders use short cranks.

I don't have a picture of my helmet and neck, but it looks like this youngsters although I am only 18 degrees back and this picture is maybe 12-14 degrees...(???)

https://worldultracycling.com/wp-content/uploads/2017/08/PastedGraphic-3-400x300.pngimgurl=https%3A%2F%2Fworldultracycling.com%2Fwp-content%2Fuploads%2F2017%2F08%2FPastedGraphic-3-300x225.png&imgrefurl=https%3A%2F%2Fworldultracycling.com%2Frecord%2Flarry-oslund-100-mile-outdoor-track-record%2F&docid=Tn5uo3oBzsiVFM&tbnid=YTP6BqTfvo-AZM%3A&vet=10ahUKEwjovfrP0qriAhUjhOAKHYeABDwQMwg9KAAwAA..i&w=300&h=225&bih=431&biw=877&q=larry%20oslund%20record&ved=0ahUKEwjovfrP0qriAhUjhOAKHYeABDwQMwg9KAAwAA&iact=mrc&uact=8

 

[Osiris]

I have not rigorously tested but a more reclined neck angle puts my chin closer to my chest AND more significantly aids breathing. Now, you might find the opposite WRT to breathing. I have a screwed up neck. Informally, it seems to also lower the elevation of my head and seems faster. I do nonetheless intend to do testing on face shield vs just glasses.

I'd thought about removing the visor to do that sort of test, but it occurred to me that I'd thereby be exposing the lip of the helmet to the air stream. My other helmets are no better in this respect. The problem with all of them is that they were designed to be worn with the rider's head facing slightly downward, precisely the opposite orientation that it would be in on a recumbent. What we need is a helmet like this one:

 

[Bill Wightman]

You don't need the helmet. You just need the control knobs on the chest for slow and fast. Who cares about power and aerodynamics! You will also have to let go of the beautiful woman at least for a little while.

 

[ed72]

I'll take a set of nobs over an App anyday.

 

[Osiris]

Today I thought I'd take the V20 out to my testing ground. Wind conditions were perfect, so I repeated the same two mile segment I ran last weekend on my M5. I make certain to wear identical riding gear each time I do one of these tests, so today I wore my racing helmet on the V20. It's poorly ventilated, so I much prefer my other helmet when riding the V20, but it's not as aero. So here are the results:

M5: 26.6 mph average @ 233 watts

V20: 25.3 mph average @ 229 watts

Not bad at all. I had expected the V20 to be much slower due to the M5's aerodynamic advantage, but it really exceeded my expectations. The M5's advantage is bound to increase as speeds go up, but since this is all the power I'm able to maintain currently, it's not an advantage I'll be able to capitalize on any time soon.

A couple of observations. I've noticed that I need to ride at least five miles to be warmed up. Prior to that, power output is 20-30 watts less, and this is consistent no matter which of my three recumbents I ride. I also see that when performing the two mile test, my power output seems to drop after about a mile, but then it increases again. I've seen this happen four times now. Since this is solely a measure of power output, it can't be accounted for by variables like wind or slope. Not sure what causes it.