Bacchetta 700c

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Re: Bacchetta 700c

Postby Hotdog » Mon May 21, 2012 10:24 pm

Baalzamon wrote:And here I was thinking it would be hard to draft a bacchetta, how wrong I was proven :mrgreen: I successfully drafted a CA 2.0 on sunday in Phil's Ice Vortex+. It was his CA2.0 I was drafting 8)


I've discussed the drafting of Bacchettas with road bike riders on group rides. The consensus seems to be that it is possible and indeed worthwhile but, unsurprisingly, the draft is less than when following another road bike and it does require the drafting rider to get down low in their drops and tuck in closer than they might do usually.

How it works at all from down at trike level I don't know ;-)

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by BNA » Mon May 21, 2012 10:27 pm

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Re: Bacchetta 700c

Postby Phil » Mon May 21, 2012 10:27 pm

Hotdog wrote:
Baalzamon wrote:And here I was thinking it would be hard to draft a bacchetta, how wrong I was proven :mrgreen: I successfully drafted a CA 2.0 on sunday in Phil's Ice Vortex+. It was his CA2.0 I was drafting 8)


I've discussed the drafting of Bacchettas with road bike riders on group rides. The consensus seems to be that it is possible and indeed worthwhile but, unsurprisingly, the draft is less than when following another road bike and it does require the drafting rider to get down low in their drops and tuck in closer than they might do usually.

How it works at all from down at trike level I don't know ;-)

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The wheels are going to be your biggest issue weight wise, eighteen months ago in the mid 120s, and managed to drop 30kgs on the bike - I did eat an entry level set of wheels though of the first bike I bought. Replaced those with the Pro-Lite Comos 700cc - less than $200 stupidly strong, not particularly light but roll quite well, did 4,000kms on them mostly commuting on bike paths, and they were still straight and true. Not disc compatible though

The CA2 is actually rather nice to ride, its actually less bumpy than my trike (with 28mm Duranos (AT) 90 psi). Big culture shock though going from uprights to a 2 wheel bent. I am only really staring to relax and get comfortable after three weeks. Commuting everyday helps.

You are not going to have the discs with the CA2, that was not a deal breaker for me. Cable discs are a lot better in the wet, but not that much better in the dry (braking feel on hydraulic discs is best of the lot though).

I have no regrets buying the CA2 - well only that it took me this long to try it. It all depends on your background, do you come from a Roadbike background before your spinal surgery? If so the CA2 once you get used to it (and part of getting used to it is getting the muscles to play nice with being used in a manner they probably never have before) will be a bit of a weapon, I am uploading my rides on Strava and surprisingly getting PBs on segments whilst my inner quads are still complaining about being asked to work differently.
If you want to just ride for fitness, you might well be happy with the Giro ATT, I can easily fit everything I need for a days commute in one of the Bacchetta Brainbox bags, which goes on and off the seat in five seconds, but if you need to carry more than the approximate ten liter capacity, then you start talking underseat and/or rear racks (and I am not sure they are available for the CA2? Underseat maybe??).

Really buy what you like more, the more you like it the more you will ride, the more you ride the faster the weight will drop off, the cholestrol and Blood Pressure come down, and the better you will feel. Don't be concerned by the weight limits - they will only matter for a short while. If you base your decision on them as they are, then you will proabably end up buying two bike bikes fairly quickly and not one, but we can't spend your money for you.
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Re: Bacchetta 700c

Postby Phil » Mon May 21, 2012 10:34 pm

Hotdog wrote:
Baalzamon wrote:And here I was thinking it would be hard to draft a bacchetta, how wrong I was proven :mrgreen: I successfully drafted a CA 2.0 on sunday in Phil's Ice Vortex+. It was his CA2.0 I was drafting 8)


I've discussed the drafting of Bacchettas with road bike riders on group rides. The consensus seems to be that it is possible and indeed worthwhile but, unsurprisingly, the draft is less than when following another road bike and it does require the drafting rider to get down low in their drops and tuck in closer than they might do usually.

How it works at all from down at trike level I don't know ;-)

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Haha yeah had a couple of roadies drafting me on the way home tonight, but was only fair as I sucked their tail for a couple of kms.

Yes certainly seemed to work I could only see the flag and Stuart's head in my mirrors, but we were cruising long into the Easterly on the way back from Fremantle, and he did not look like he was having to put too much effort in to keep up. You would think that the trike is too low to benefit, but does not appear to be the case. I will ride the trike later in the week to work and find some roadie to be my rabbits/draft squad.

Going into Freo though, could not keep up on the downhills. Just rocketed away.
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Re: Bacchetta 700c

Postby Baalzamon » Mon May 21, 2012 11:58 pm

Hotdog wrote:
Baalzamon wrote:And here I was thinking it would be hard to draft a bacchetta, how wrong I was proven :mrgreen: I successfully drafted a CA 2.0 on sunday in Phil's Ice Vortex+. It was his CA2.0 I was drafting 8)


I've discussed the drafting of Bacchettas with road bike riders on group rides. The consensus seems to be that it is possible and indeed worthwhile but, unsurprisingly, the draft is less than when following another road bike and it does require the drafting rider to get down low in their drops and tuck in closer than they might do usually.

How it works at all from down at trike level I don't know ;-)

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Wheels generate a little draft and seat does as well, not as good against a DF, but better than wind :)
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Re: Bacchetta 700c

Postby Hotdog » Tue May 22, 2012 1:38 am

Bobmcar wrote:Been a few weeks but I finally got up to see Ian at Flying Furniture and rode a few recumbents, won't say I was an expert but felt reasonably comfortable to ride around after about 10-15 minutes practice. Rode a Giro ATT26 which was really great. Now I have abit of a dilemma which I though you more experience riders might have a point of view. The ATT26 seems a good fit as at my present weight 110 kg I'm at the higher weight limit, but with more work I trust I will get back down to more normal 90 kg ( blew out after I had some spinal surgery). Ian said diplomatically that the 26"wheels would be stronger and that later I could swap over to the 700's when I was ready, the disk brakes appealled also. As I want to use this for my weekend bike mostly and perhaps a one day commute seemed idea. Ian also had a CA2 650 there as well, didn't have the 700 wheels but is rated to take 110kg and is quite light being carbon and would be quick. The dilemma is if I get the ATT26 will I be disappointed later as I become more competent that I didn't go the CA2. Thought there maybe a few riders who could comment based on their experience.
Cheers
Bob


Ian's comment about 26" wheels being stronger than 700c is fair enough if you're comparing typical 26" MTB wheels with low spoke count super-light road race wheels but it's perfectly possible to get sturdy 700c wheels if that's what you need. Aside from some tandem and 29er wheels I doubt there are many stronger 700c wheels than the ones I built for my Giro. Stiff deep-V rims (HPlusSon Formation Face) and 32 spokes front and rear makes for very tough wheels, despite a rider who has been up to 95 kg, the weight of a large framed steel Giro often loaded down for commuting and any number of big pot holes hit at speed I've never even had to re-true them. Less extreme options are of course available and would likely be more appropriate for a primarily weekend bike, for example I've been very happy with the HED Kermesse wheels on my CA2.0. They're the 24 spoke 2-cross laced variant of the HED Ardennes which I chose to get a durable but decent performance wheel, and in practice they do seem to be pretty tough. They aren't disc compatible wheels though, but it would be possible to build something similar that was. Basically I wouldn't choose between 26" and 700c wheels on the basis of wheel strength, you can always get strong enough wheels in either size.

As far as the Giro ATT versus the CA2.0 goes, I've never ridden an ATT but I suppose as an owner of an older steel framed but disc equipped Giro and a CA2.0 I suppose I can offer a few comments. Based on my experience with my Giro I would say that the ATT would be an excellent and very versatile bike, one that would be likely to keep you happy for years (as my Giro did for me). With the right engine the Giros are very quick bikes, and the disc brake option is a big bonus, I'm totally sold on the benefits of disc brakes for road bikes. That said I must admit that over the last few weeks I've been enjoying riding my CA2.0 so much my Giro hasn't got a look in. I bought the CA2.0 with the intent that it would be my weekend bike and perhaps occasional commuter with my Giro remaining my everyday commuter. That has generally been the case but right now my Giro has been relegated to rain bike, and it hasn't been raining. The CA2.0 may not be that much quicker but as a lighter bike it definitely feels quicker and more nimble. It's the ride quality that really stands out for me though, the carbon frame, fork and seat do a great job of smoothing out bumps and vibration. Don't get me wrong, the Giro its still good in this respect but if you regularly contend with bad roads as I do then the carbon can make quite a difference. The only thing I don't like about the CA2.0 is the brakes, I have the X-Eyed calliper brakes which most people seem to think are good but having been spoilt by the disc brakes on my Giro I regard them as merely adequate in the dry and this is not a bike I want to ride in the wet. This is a big enough issue for me that I've actually been seriously looking into the possibility of a front disc brake conversion for the CA2.0.

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Re: Bacchetta 700c

Postby Bobmcar » Tue May 22, 2012 7:57 pm

Hi Hotdog & Phil, thanks for the replies. I have done abit of riding over the years (37 years) but have to admit I really did enjoy riding my racer most, not necessarily in a group, but can't beat it on an early sunny morning, no wind,just motoring along, brilliant - probably what has me leaning towards the CA2 slightly that now I can't do the longer distances pain free anymore. I appreciate your experiences, sounds like you are both happy with your CA2's. The practical part of me says the ATT26 with disk brakes, probably stronger wheels should be where i begin my recumbent journey but the Impulsive/crazy part says go for the CA2. Never spent quite this amount of money on one bike ( although with upgrades probably close to it), but the accountant - read wife :-), is supportive which is great. I will wait a few days and make a decision later this week. Price will change with next shipment as our dollar has dived 10% since last shipment, but I want to get the right outcome so will take on board your comments. As I said don't want to upgrade in 12 months, after I am more confident on a recumbent, but am I biting off a bit too much with a CA2 as a beginner?
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Re: Bacchetta 700c

Postby william » Tue May 22, 2012 8:33 pm

Hi Bob,

Sounds like your brain is going through some agony and I think your intuition is getting glanced over whilst the instinct is there, but scary.
Most recumbent riders always test the water on a lesser vehicle before they know what the really WANT. What you need will depend on the circumstances.
If you are looking at one machine because of sensibilities and lusting after something else you know you will want then eventually you'll be swayed to lust. Always happens.
Between the Corsa's and Giro ATT there is a small handling difference but the CA2 will be more comfortable, a little faster and quicker off the line. Other things will surface but the platform is essentially the same, components aside. Carbon seat improves things a little too.
If you're in Melbourne give me a PM and you can take mine for a spin before you go to Canberra.

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Re: Bacchetta 700c

Postby Rowley Runner » Wed May 23, 2012 1:32 am

Re try before you buy. Bob/anyone

I have a low racer going cheapppp if you want to buy before you buy (as in layout some proper money a bent.)

$350 for a flying lizard anyone??????
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Re: Bacchetta 700c

Postby Baalzamon » Wed May 23, 2012 10:35 am

Rowley Runner wrote:Re try before you buy. Bob/anyone

I have a low racer going cheapppp if you want to buy before you buy (as in layout some proper money a bent.)

$350 for a flying lizard anyone??????


Now where is pictures... Hope this doesn't tempt me as I don't need this right now buuut lol
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Re: Bacchetta 700c

Postby rdp_au » Wed May 23, 2012 1:06 pm

Baalzamon wrote:
Rowley Runner wrote:Re try before you buy. Bob/anyone

I have a low racer going cheapppp if you want to buy before you buy (as in layout some proper money a bent.)

$350 for a flying lizard anyone??????


Now where is pictures... Hope this doesn't tempt me as I don't need this right now buuut lol


Ohh, Ohh, don't forget, my bentech is still for sale..

[*]http://www.bicycles.net.au/forums/viewtopic.php?f=29&t=51049

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Re: Bacchetta 700c

Postby Baalzamon » Wed May 23, 2012 1:09 pm

But photos really assist :)
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Re: Bacchetta 700c

Postby John Lewis » Wed May 23, 2012 1:13 pm

Rowley Runner wrote:Re try before you buy. Bob/anyone

I have a low racer going cheapppp if you want to buy before you buy (as in layout some proper money a bent.)

$350 for a flying lizard anyone??????


Is that a Poit type Lizard?
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Bacchetta 700c

Postby Rowley Runner » Thu May 24, 2012 2:16 pm

I'll post picks of the lizard tonight.


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Re: Bacchetta 700c

Postby Baalzamon » Sat May 26, 2012 12:09 am

Rowley Runner wrote:I'll post picks of the lizard tonight.


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Now friday where?
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Re: Bacchetta 700c

Postby Hotdog » Sat May 26, 2012 1:17 am

Not that I'm not interested in the Lizard photos but this is perhaps getting a bit off topic, maybe put this in another thread (and link to it from here)?
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Re: Bacchetta 700c

Postby Hotdog » Sat May 26, 2012 2:51 pm

OK, back to Bacchettas. I gave my CA 2.0 a wash, polish (Pedro's Bike Lust silicone polish FTW) and tune up today and decided to take the opportunity to take a few photos while it's still clean.

Full bike shots (click for bigger):

Image

Image

Image

Some close ups to show the metallic finish on the frame:

Image

Image

Image

I also decided to weigh the bike, using the bathroom scale differential method. The 'real world' weight including lights, bag, pump, tools and spares came out as 11.2 kg. The 'naked' weight without all those things is 9.8 kg.

Edit: For comparison the 'real world' weight of my Giro is about 17.1 kg, almost 6 kg heavier. That's a large size steel frame Giro though, with heavy wheels, triple crankset, disc brakes front and rear, mudguards, extra lights and under seat bags as well as a seat back bag. A Giro ATT (aluminium frame) medium size with lightweight wheels and drivetrain would be a lot lighter than that. My CA 2.0 is medium size, has medium weight wheels, a light compact double drivetrain and lightweight calliper brakes.
Last edited by Hotdog on Sat May 26, 2012 4:39 pm, edited 2 times in total.
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Re: Bacchetta 700c

Postby Baalzamon » Sat May 26, 2012 2:56 pm

I notice you don't have grips on the handlebars?
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Re: Bacchetta 700c

Postby Hotdog » Sat May 26, 2012 3:04 pm

Baalzamon wrote:I notice you don't have grips on the handlebars?


Yeah, the handlebar arrangement in general is a 'temporary' lash up that I've never got around to tidying up. I still intend tweak the cable lengths, wrap the cables up neatly in bar tape and put some sort of grips on the ends of the bars, either some simple foam grips cut to length or some more bar tape. All of that is essentially cosmetic though, you don't actually need grips on a bike like this.
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Bacchetta 700c

Postby rdp_au » Sat May 26, 2012 3:54 pm

My goodness, all that shiny carbon fibre does look very nice indeed! The way you have it set up looks quite different to mine. Your seat is impressively reclined - I think I'd struggle to touch the ground with the seat that far back! Also note you have the bars set quite low. On mine i pretty much copied the recommendations on the bacchetta website and have the grips pointing more directly back towards me, so my hand is almost on the end of the grip. Feels quite comfortable.

Had my first real ride in the rain last Thursday on the way home from work and have to say that the 'crud buster' mudguards did a fine job. Bike and I were both sodden and I was cold, but the bike was commendably clean. Just needed a quick wipe over and it was fine. The 'brain box' bag kept the water out pretty well too.


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Bacchetta 700c

Postby Rowley Runner » Sat May 26, 2012 5:07 pm

Image Image Image Image Image Image. Pics of lizard as promised. Bit late sorry. LX 8 speed. New tyres and tubes. Rack with vaude panniers (if wanted) Bromton front fork with 1 and a bit inches of travel (surprisingly effective) new gear cables. Really easy to ride. Cheap!


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Re: Bacchetta 700c

Postby Hotdog » Sun May 27, 2012 3:17 pm

rdp_au wrote:My goodness, all that shiny carbon fibre does look very nice indeed! The way you have it set up looks quite different to mine. Your seat is impressively reclined - I think I'd struggle to touch the ground with the seat that far back! Also note you have the bars set quite low. On mine i pretty much copied the recommendations on the bacchetta website and have the grips pointing more directly back towards me, so my hand is almost on the end of the grip. Feels quite comfortable.


Yep, whoever is making these frames for Bacchetta does a fantastic job on the finishing, they look great.

The angles in the photos and the fact I'm not on the bike might be making my setup look a bit more unusual than it really is. I think my actual riding position is also pretty close to the suggestions on Bacchetta's website, though it is a little hard to tell without seeing a photo of yourself on the bike.

I do like my seat reclined quite far, though mine is still within the normal range as far as I can tell. It's generally the case that recent Bacchetta owners start off with their seat fairly upright as it helps with low speed balancing, but later on most with gradually recline it further until they find the maximum recline they're comfortable with. If I remember correctly this usually results in the middle section on the seat being about 15 degrees above horizontal. As for reaching the ground from the reclined position, I have a few factors in my favour. My leg length is towards the upper end of the range for a medium sized frame so my seat is positioned further down the main tube than it would be for most and because of the slope of the tube that means closer to the ground. The CA 2.0 uses a seat attachment plate instead of the seat clamp used on the metal bikes, this has a lower stack height which further reduces the height of the seat above the ground. The carbon seat itself has a lower stack height than the Euromesh too, so that also lowers the seat height a bit. Finally the lip on the carbon seat is small and rounded which prevents it getting in the way when dropping a leg to the ground.

Regarding the handlebars, they're not really low. With the recline I have on my seat the grips are close to my shoulder height (where they should be) and with my arms held out horizontally with a comfortable slight bend in the elbow the reach is just right, my hands fall naturally on the grips. I would actually like to lower the handlebars a bit, currently the clearance between my shins and the sideways section of the bars is way more than necessary and reducing it a bit would improve my forwards view. I'd need to trim some material off the lower part of the telescopic riser with a pipe cutter to get it any lower though. Having made that adjustment I would rotate the bars a bit to get the reach and grip height back to roughly where it currently is.

Had my first real ride in the rain last Thursday on the way home from work and have to say that the 'crud buster' mudguards did a fine job. Bike and I were both sodden and I was cold, but the bike was commendably clean. Just needed a quick wipe over and it was fine. The 'brain box' bag kept the water out pretty well too.


I got caught in the rain on my way home too that day. It was the first time I'd ridden the CA 2.0 in the rain, usually I ride the Giro if there's rain in the forecast. I was curious how the brakes would perform in the wet, I'm happy to say that the X-Eyed callipers with Koolstop Salmon pads were better than I'd feared. I'm still a lot happier with the disc brakes on the Giro when it comes to riding on wet roads though.


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Bacchetta 700c

Postby rdp_au » Tue Jun 05, 2012 8:47 am

Pictures can indeed be deceptive - to while away some time on Sunday morning, instead of riding in the rain :-(, I decided to measure my seat angle. Using a bit of a heath robinson setup of spirit level and protractor, it came out to just on 20 deg. Quite a bit more reclined than I thought. There was no particular science in setting it up, I just picked a setup that looked ok and started riding. It feels quite comfortable, but I wouldn't want it any more reclined as I'm on my toes when stopped and sitting back in the seat. I probably could have gone with a medium frame rather than the large I have. This would move the seat back by around 25mm and as hotdog observed, lower it as well. Could also be an excuse to upgrade to a carbon seat.


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Re: Bacchetta 700c

Postby John Lewis » Tue Jun 05, 2012 9:38 pm

It's interesting to consider the optimum seat angle.
In an unfaired bent the more laid back you are the more aerodynamic you become.

Some research has been done that suggests this is true only up to a point. At some stage the power lost through recline is greater than the aero losses.

The article that starts on page 10 of the pdf linked below suggests that the higher the BB within reason the better. from seat height to 3 inches above is mentioned as best.

The angle from BB to hips to shoulder or in other words the seat angle (My paraphrasing) is optimum at 120 degrees.

I started looking into this because I had to change the seat position on the velo and suddenly didn't seem to be able to get as much speed/power as previously.

Anyway, have a look and see what you think.

John

http://www.ihpva.org/HParchive/PDF/27-v8vn1-2-1990.pdf
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Re: Bacchetta 700c

Postby Hotdog » Tue Jun 05, 2012 11:45 pm

Interesting reading, thanks for posting that John.

I have heard about the concept of the optimum 'hip opening angle' (referred to in the linked article as riding angle) from a number of sources, and it all sounds plausible to me.

Bacchetta themselves do allude to this in their bike fitting advice, their recommendation is to experiment with increasing seat recline until you feel uncomfortable or notice a reduction in climbing ability, i.e. significantly reduce your power output due to an excessively open hip angle. It seems to be generally accepted in the community that an element of compromise between aerodynamics and power delivery is inevitable for an unfaired recumbent, i.e. you have to trade off level ground cruising speed versus climbing and sprinting ability. The ideal seat angle for maximum speed therefore depends somewhat on the terrain you'll be riding over, for a very hilly route the seat should be adjusted for the roughly 120 degree maximum power position while for a flat course a slightly more reclined position would be better despite the power delivery reduction.

The other side of the optimum hip opening angle seems to be well understood for upright bikes. A typical road racing bike gives a hip opening angle close to this optimum power angle (and allow the rider to change their hip angle on the fly by switching between the tops, hoods and drops of their handlebars) and these bikes unsurprisingly set the standard for hill climbing ability. Time trial and triathlon bikes, on the other hand, force the rider into more closed hip angles in order to place the rider's torso in a horizontal position. It is well known the riders are unable to deliver as much power in this position but the improved aerodynamics more than make up for it over flat or moderately hilly courses.

If you believe all this then it naturally explains why high racers and low racers are the fastest types of unfaired recumbents, both have very similar rider positions with a high bottom bracket allowing an aerodynamically reclined seat angle to be combined with a powerful hip opening angle. Even with the high bottom bracket the most aerodynamic seat angle will probably still be somewhat different from the most powerful one and a compromise must be chosen.

When I first got my Giro I just kept gradually increasing the recline a step at a time until I felt like I'd gone too far, went back up a step and settled there. When I got the CA 2.0 I initially set it up to be roughly the same as the Giro and then started experimenting again. For some reason (I think the different shape of the seat is the main one) I found that a slightly more reclined seat angle 'felt right' on the CA 2.0. I've never taken the time to attempt to compare my performance with different seat angles but reading the discussion in this thread has inspired me to do some more experimenting. I do suspect that my current position on the CA 2.0 is a bit too reclined for best hill climbing, the description of the ergonomic effects of excessive hip opening angle in the linked article (almost exclusive dependence on quads for power, knee strain following big efforts) sounds very much like my experience.
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Re: Bacchetta 700c

Postby rdp_au » Thu Jun 07, 2012 6:27 pm

The Corsa has new feet

I'm very happy with the Corsa in its standard guise, but that doesn't mean I'm immune to a little customising. I felt the standard wheels and Kendra tyres were pretty basic, and the collective wisdom seemed to be that the best avenue for upgrade to improve performance was the wheels. So after quite a bit of web surfing, I chose a set of Velocity A23 comp wheels, shod with Continental GP4000S tyres. The rims are wider than normal for a performance wheel, at 23mm vs the standard 19mm. This is supposed to create a more aerodynamic rim/tyre combination, and also improve the feel and traction of the tyre. I chose a strong build, with 28 front and 32 rear spokes as I think recumbents are hard on wheels as we can't shift our weight to give the wheels an easier time when negotiating rough terrain. The front is radially laced, and the rear a hybrid, with cross lacing on the drive side and radial on the non drive side. Weight is listed as 730 grams front and 850 grams rear, so they are not the lightest around but I hope will be durable. I think they look pretty slick

Image



and here is the bike with her new feet, smiling and ready for a ride
Image

Took them for a quick shakedown run from Hornsby up to Berowra and back. They felt pretty good and must roll pretty well, as I was able to average over 31kph on the trip.
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rdp_au
 
Posts: 513
Joined: Wed Feb 07, 2007 4:45 pm
Location: Hornsby, Sydney, NSW

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