My Very First Recumbent is a V20

[Frito Bandito]

Finally surpassed my goal of 40kph on a flat 50km course with a 40.2kph (25mph) average speed up and down the river to negate the wind. My CdA for the ride was 0.198 where it is usually around 0.205-0.210. My watts for this ride and my previous PR (personal record) were 209w for 39.3kph, but the difference this time was that I had a DIY front disc as opposed to the 50mm Campagnolo Bullet. So, the front disc essentially gave me 1kph. It was a very slight hurting crosswind from the left going down the river and then a slight helping wind from the right coming back up the river.

Here is the ride...

Follow Andrew on Strava to see this activity. Join for free.

Join Andrew and get inspired for your next workout

www.strava.com

 

[vosadrian]

Nice work!!

 

[Frito Bandito]

I can get this rear Xentis Mark 1 TT tubular wheel for US$789 brand new from a shop here in Japan and trying to justify doing so. Finding good tubular tires is a PITA though.

How does "Tubular on the front means if I get a flat up there the tire won't come off and I'll have a better chance of not crashing severely" sound?

 

[John Formsma]

It's a good idea in theory, but not in practice. If you have a flat, you have to either repair the tire and glue it on again, or glue on a new tire. Either way, you wouldn't carry all the stuff on your ride to deal with a tubular. That's what your team car is for, and yeah, you're getting fast enough now to demand a team car.

If you're looking for a better option, try road tubeless. With RT, the tire that won't come off the rim with a flat. Same benefit as tubular but possible to install a tube if you have a flat. Tubeless tires ride sooooo much better on a road bike, but I doubt you'd notice any difference in ride quality on a V20. A bit less rolling resistance with a tubeless (at proper pressure anyway), but probably not any noticeable difference in speed.

I haven't run them on the V20, but used them almost exclusively on my road bikes from 2009-2019, They're not perfect, and you have to learn how to work with them. But at least you can deal with a flat on the road (clean up sealant, install tube, and ride on). Dealing with the sealant is a pain when it doesn't seal, but most of the time it seals well and you never notice anything.

For what it's worth, I've had one flat on the front with the V20, and it wasn't unstable at all. I was on perfectly flat road though. However, my buddy who got me into the Cruzbikes had his first front flat during our only ride together so far. He crashed suddenly and loudly, but was mostly OK except for the scrapes and later bruises. I'm not sure if it was his handling or what. My front flat wasn't any big deal at all. I'm probably gonna stick with tubes for now. They're easier to deal with.

 

[Frito Bandito]

Thanks for the compliment John. How I would love to ride in an event that needs a team car hahaha.
I was really hoping for a "Yeah, that is a great looking wheel. She might believe your reasoning and not want you to be put in the hospital AND have to buy a new bike, so you should buy it"

Seriously though, running tubeless on my Bullets does okay. I have to install the tubeless tire on a different rim for a while to shape it so that when I finally put it on my Bullet 50 I can get it to seat with a floor pump. When it finally does go flat while riding I can just dump out the sealant and install a tube.

The roads here are smooth and very clean so I get around 5-6000km out of my usual tires before the threads start appearing and the sealant typically lasts for about as long before starting to ball up. In a quick search last night I read that sealant on tubulars would help with small punctures. I figured that tubulars would last about 4-5000km since they are usually thinner and I might not mind changing the tire a bit more frequently.

Surprisingly I had 2 front flats in 1 day on the front of my V20. They weren't blowouts so I was able to keep it upright but had they happened in fast turns it could have been bad.

 

[vosadrian]

When I first got my V20 it had the the standard wheel/tyre setup they come with with Conti GP4ks 25mm tyres and tubes. I was getting a puncture every few hundred kms where I ride, and I had a couple of high speed front wheel punctures (in a straight line) that I was able to stop safely (sit up with feet unclipped hovering over the ground and slowly bring the speed down). When I changed to deep wheels, I got tubeless running GP5K-TL 25mm and stans race sealant. I've had only 1 road side stop (sidewall tear so fit tyre boot and tube) since (around 8000kms). I have had quite a few sealant repaired punctures including a couple that would not hold high pressure, so I removed the tyre at home and fitted a patch. Even the sidewall tear went down fairly slowly, so I was able to stop before it was fully deflated. I can't speak highly enough of tubeless. I am considering the tyre liners, but not sure they offer that much given my current experience. If I had the liners, I probably could have ridden the sidewall tear home.

 

[Frito Bandito]

I think tubeless GP5000s and the Schwalbe Pro Ones are about as good as it is going to get for protection and RR.

I had a front tire blowout on my road bike doing about 50kph in a straight line right next to a cement truck but was able to keep it upright. The tire and tube stayed on so I was lucky. I do love tubeless and I wish the Xentis was tubeless instead of tubular. I am just trying to talk myself into a good enough reason to buying something faster than my Bullet 50 haha. It is a CF brake track that Xentis recommends using regular pads on, the Hub is IIRC essentially a DTSwiss 240.

Oh! I almost forgot! It has TURBULATORS!!!!

 

[Gary123]

I would never ride a v without tubeless. Mine came with gp4ks and did the pothole front flat crash thing at about 500 miles in. Happened later on with tubeless and no problem staying up.

 

[vosadrian]

I see pro TT guys using both these full carbon non-spoked wheels as well as traditional spoked deep wheels. I take this to mean they both work similarly well (or they would all use what worked best). So is there a speed benefit.... or is it more for bling?!?

I think it was discussed earlier in this thread. I would not personally ride a tubular for my typical riding roads. But if your roads are more fogiving on tyres and you think you can get many kms between punctures, I say go for it. One benefit of tubs is that they are more resistant to punctures from bumps/pot holes. But if you get glass, thorns, screws or other sharp debris, I would avoid tubulars.

 

[Frito Bandito]

Vos, in reality, the consideration is almost all BLING. I am not even sure if a Mark 1 TT on the front is more aero than a Bullet 50 since neither of them post their data. And even if they did post their data it would likely be only the wheel in a wind tunnel, not on a bike, with a rider, and much less on a V20. Public roads here are really great. I haven't had a puncture in about a year, and I only see a rider on the bike paths with a flat about once a month or more.

 

[vosadrian]

Sounds like your decision is made then!

 

[Frito Bandito]

Sounds like your decision is made then!

If it were tubeless compatible then I just would have posted a pic of it already on my V20. Xentis does make a Mark 1 Clincher but I don't know yet if it is tubeless compatible yet. And there is a set for $700 with 60km on it near me.

 

[Jeffers]

Finally surpassed my goal of 40kph on a flat 50km course with a 40.2kph (25mph) average speed up and down the river to negate the wind. My CdA for the ride was 0.198 where it is usually around 0.205-0.210. My watts for this ride and my previous PR (personal record) were 209w for 39.3kph, but the difference this time was that I had a DIY front disc as opposed to the 50mm Campagnolo Bullet. So, the front disc essentially gave me 1kph. It was a very slight hurting crosswind from the left going down the river and then a slight helping wind from the right coming back up the river.
View attachment 13869
Here is the ride...

Follow Andrew on Strava to see this activity. Join for free.

Join Andrew and get inspired for your next workout

www.strava.com

Congratulations on this amazing achievement.
I've added your bike to my hip angle collection. It's slightly tighter than most Vendettas I've measured.

 

[Frito Bandito]

Thank you Jeffers, that is good to see. I have 2cm of foam backing under my shoulders, and 1cm under my butt, so when I have to replace my foam padding I can put only 1cm over the whole seat to get my head a tad lower. I'll still put 2-3cm for lumbar support though and hopefully that will help my CdA.

Speaking of it (again?) my last few rides have been 0.210-0.225 instead of around 0.200, and all of those high ones have been without my hydration pack on my chest. Next ride I am going to wear it again and see if filling that space between my chest and the bars helps.

 

[Frito Bandito]

On longer rides of 60km or more I started to have a leaning head issue when fatigued so I began experimenting. What I have now is light, and has less moving parts while still being a bit adjustable on the go for those longer rides in which lack of comfort starts being an issue. The width of the Performance Adjustable Headrest bars set at the widest position is better for this IMO than the stock head rest bars. I cute a few curved pieces of a small plastic trash can bought from a Dollar Store that kind of matched the width of my neck and attached a 1cm thick foam pad to it. I put two small foam handles over the head rest bars for a bit of cushioning and wrapped velcro around them. Then I put 2 strips of velcro on the outer edges to match the width of the PAH bars. It took a bit of adjusting the bars to get it just right, but my neck sits in the cradle comfortably. I can adjust it higher or lower by hand without stopping by sitting up a few centimeters pulling 1 side off and moving it up or down, and then doing the other side. The under seat bag in back is connected to the base bar with a simple hose clamp. Now that it is cooler the 600ml bottle that fits in back is likely enough to get me to 100km without stopping, which weight-wise is awesome, but aerodynamically, that bag is barely better than nothing. At least it stops the spray from hitting me in the neck, but it still flings it onto the back of my helmet.

 

[Frito Bandito]

While that small bag in back is light and handy for keeping a small tool kit and spare tube as well as a 600ml hydration bottle, my CdA has been creeping up from around 0.200 to almost 0.23 with it, so it's time to go back to the 6L Rixen Kaul bag hose clamped to the Performance Adjustable Headrest to see if I can get it back down to about 0.200.

 

[macg4d1g]

If it were tubeless compatible then I just would have posted a pic of it already on my V20. Xentis does make a Mark 1 Clincher but I don't know yet if it is tubeless compatible yet. And there is a set for $700 with 60km on it near me.

Saw these (Vittoria Air Liners - https://www.vittoria.com/us/en/bike-accessories/tire-inserts/air-liner-road) reviewed on GCN the other day. Seem like a good idea and something I might consider for my front wheel but have no experience nor do I know personally anyone who has tried them.

 

[Frito Bandito]

Saw these (Vittoria Air Liners - https://www.vittoria.com/us/en/bike-accessories/tire-inserts/air-liner-road) reviewed on GCN the other day. Seem like a good idea and something I might consider for my front wheel but have no experience nor do I know personally anyone who has tried them.

I wonder how much if at all they affect rolling resistance.

 

[macg4d1g]

I wonder how much if at all they affect rolling resistance.

I believe they claim none. When the tire is normally inflated, they shrink down flat against the rim. Hence, rolling resistance and handling is unaffected unless there is a loss of tire pressure. Then the air liner expands to fill the tire and support bike and rider. The only penalty might be a slight loss in acceleration due to the little weight the air liner adds. They are supposed to be unaffected by and non-interfering with the tire sealant. Some professional race teams have been using/testing them the past few years especially when racing on cobbled courses. Here is a 2 minute video I found by Vittoria if you're interested:

It has a graphic that shows how the liner shrinks under pressure.

 

[Jeffers]

I have a larger bag than that yours mounted behind my head. Actually larger than I really need.
One day I looked at it and thought 'I really don't need those large cargo pockets on both sides of the bag'.
So I unstitched them. My avatar is before I removed the cargo pockets. Now it's a little less than the width of my head and more like an extension of my aero helmet. Actually tapers towards the back cuz my stuff shifts forward from gravity.