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Road tubeless has arrived!!!

Monday, November 12, 2018

Road tubeless has arrived!!!

That's right! In fact it arrived over a year ago. At first the big plus to road tubeless was that it got a lot of folks to use sealant. With sealant, you only have to stop and repair half your flats, or less. The rest take care of themselves. Have a look here to pick a good sealant.

But now the data from Jarno Bierman at Bicycle Rolling Resistance shows us much more. Jarno has been doing independent rolling resistance tests for a few years now, and not just on road tires. Unlike others who have done this work, notably Tom Anhalt and Al Morrison, Jarno has been doing puncture tests too. This way you get a more complete picture of each tire.

Now, click here and have a real close look at the data. We all expect that as tires go down the list from fast to slow, that puncture resistance will tend to increase. Generally for road tires, fragile means fast, and heavy means slow. So look down the list in the puncture resistance column. One good way to pick a fast tire is to decide how much puncture resistance you need, and look for the tires nearest the top of the chart that have enough. If you do this, you will see what I see. At almost every step up in puncture resistance, at tubeless tire is the fastest! Have a look down the Puncture Test column:
  • 8/5 Vittoria Corsa Speed G+ , the fastest road clincher, period.
  • 9/5 Hutchinson Fusion  Galactik TL, first tire to hit 9 on the tread.
  • 11/6 Schwalbe Pro One Tubeless, first tire to 11 on the tread and to 6 on the sidewall. 
  • 12/8 Schwalbe One Tubeless, first tire to 12 and to 8, and its a few years old. 
  • 13/8 Schwalbe Ironman Tubeless, first tire to 13 on the tread, older and hard to find though. 
  • 16/9 Panaracer Race A Evo 3, the only tire to hit 9 on the sidewalls!
  • 20/7 Pirelli Cinturato Velo TLR, first and only tire on the list to hit 20 on the tread!
You can see that at both the fast end and the most puncture resistant and of the chart, tubeless dominates. Between each of these tires are almost all tubed tires that are slower and easier to puncture. So at a lot of puncture resistance levels, these tubeless tires are the best choice.

The tubeless advantage is actually even bigger though. His puncture test involves trying to push a 1mm drill bit through the tire, at the tread and the sidewall. He adds weight until it goes through. In other words, this test does not involve holes being sealed by sealant. This is purely a test of the tires toughness, with both tubed and tubeless being judged evenly. A 1mm hole is easily sealed by sealant. A tire without sealant will go flat. So his puncture test does not favor tires with sealant in them. Another way to look at this is that if you run sealant, you can effectively add a few points to his puncture resistance scores!

The Continental Grand Prix 4000S2 has long been favored for its superb combination of speed and puncture resistance. Its a very popular tire. The Schwalbe Pro One and One are both faster and more puncture resistant. These 2 tires have had teething pains, but stellar warranty support, and my last set of both have been solid. The new Pirelli breaks new ground as it blows the old Gatorskin away, and in 35c would top the tour tire category as well. I am hopeful the new GP5000 TL will slot in ahead of the Pro One in both rolling resistance and puncture proofness, setting a new mark. 

With tubeless and sealant, you will have many fewer ride stoppages due to flats. The only downside is that if the sealant cannot seal it, it will be a mess to fix. Bring a tube, just like when you used tubed tires. Just don't plan on needing it nearly as much! Sealant can make a mess, but its a lot easier to clean off then chain lube or grease!

Some of these tires are fast and tough enough that even if you don't have tubeless compatible rims, or just are not ready to try tubeless yet, they are the best choice with tubes as well! There are sealants that work well in both butyl and latex tubes too. 

If you ride bikes with nonstandard tire sizes, you still don't have an excuse, as the Pro One and One come in almost all sizes from 406mm (20") to 584mm (650B/27.5") too.  The new Continental GP5000 will also be out in both 650B and 700C. 

Why are these tires all so good? Perhaps the design changes needed to make a tire tubeless compatible make it more durable.  Perhaps these manufacturers are putting most of their development budget into tubeless, and not tubed tires. 

So it comes down to this. If you want to deal with fewer flats on the road, you want sealant. If you are going to run sealant, it works better in latex or tubeless tires than it does in butyl tubes. Why run an expensive latex tube when you can run tubeless with tires that are faster than what you have now? 

The tires are a bit more expensive, but you don't need hardly as many tubes. Using tubeless rim tape on your wheels is a good idea anyway as it makes mounting tubed tires easier too, and its less likely to move like some other tapes can. Its time to go tubeless on the road!

Thursday, May 24, 2018

2018 Cheesehead-Roubiax ride report. Gravel in Wisconsin!!!

So I am on a road trip and had the sense to bring 2 sets of wheels for my Bacchetta CA3. On one set of Flo30s is a pair of 28mm Continental GP4000S2s. On the other set is a Panaracer Gravel King in 700x32c in front (almost exactly the same size as a 28mm Continental), and a a 700x32c Vittoria Voyager Hyper in back. These are about the biggest tires you can fit in a CA2/3 with X-eyed brakes. Why did I do this? Wheels take up space in a small car.

Gravel!!! I have done a few gravel roads over the years in Florida, and other places. I like it! Less traffic, and you have to pay attention more to the surface you are on, so it keeps you focussed.

So being in Wisconsin for a while, I was bummed to miss the Dairy-Roubaix. I did however have time for the Cheesehead-Roubaix! Its a 63 mile ride with about 10 miles of gravel. They rate the gravel sections just like the cobbled sectors of Paris-Roubaix, one through five stars, five being the hardest. I used google street view to get an idea of that I was in for. Sure enough, the 4 star and less sections looked just like pea gravel and hard pack. Rough texture but pretty well groomed. The first section was the only five star, Lovers Lane. This was a mile of washed out jeep trail, with sections of deeper loose gravel, big drop offs in the washed out areas, and a serious grassy crown between the deeper wheel ruts. Its mostly uphill too with 2 steeper sections. Here is what it looked like in the rain last year.

Tuesday before the ride I drove out with the CA3 and my MTB to scout the worst section. I rode in on the MTB first. Easy. Only issues I needed to worry about were: having enough speed to steer well on the bumps next to the washed out sections so I did not fall into them, picking the best line through the ruts, staying clear of the deep gravel, and of course not pinch flatting on anything. So I got back the car and switched bikes. It was all pretty uneventful on the CA3, except the top where it was hard to find firm ground next to the deep gravel in the tire ruts. I settled on the far left edge and made it without putting a foot down. Alright then. If I have the choice of riding 63 miles with 53 miles of road on the bent vs the MTB, the bent is way faster. I figure I can deal with the gravel.

Event day!! Now here is the really cool thing about a lot of gravel rides. Many are not sanctioned by any governing bodies, so ride the bike you want! Yeah, I got some looks at the start. Many have no entry fee, but donations are accepted (and really recommended if you want to support the event). Turns out there were 300 riders, so that decided to start in 2 groups. I was ready to discuss or accept any assignment directed at me specifically due to the bike, but there were none. Instead, all USAC category 1-3 riders where asked to go to the front group, so I did that. My plan was to try to get to Lovers Lane in front of the front group, or at least in a small group. I wanted to have line choice, and impede as few others as possible if I did not. Well, I tried to get away, but with all the little climbs, and a group of 80 or so chasing, that did not happen. As I recognized that we were close, I slowed and motioned all the group by me. As we turned right onto the gravel I suddenly realized that I was not in the right spot here either. I was already passing people again! On the double track I was just rut hopping from one side to the other to keep advancing. About half way up I had passed about 12 and was riding on the crown to avoid some rocks when a DF rider 2 bikes in front of me crashes and flips his bike sideways in the road. I dive for his bar and get by the guy in front of me, and the bars, or so I though. My bike magically shifted into the 11t cog! I get off and realize that something must have hooked my rear derailleur cable housing and pulled it out of the chainstay stop. It took a minute to get going again. Well, not as bad as a flat. I had to walk the gravel on the last pitch too, as the 80 riders in front of me had scattered it all over, and there was no smooth line. Maybe I should have stayed at the front of the group, or the middle?  Here is a sequence of me before the crash:

So, time to chase. I was now farther back then I should have been. I got groups together a few times, took long pulls on the flats, then they would all launch past me on the climbs, doubling or tripling their power outputs. 5 minutes later I would be riding past the strongest one of them. My pulls were appreciated though. I did this a few times, and had a nice group of 5 together when we passed the rest stop. Lots of riders there. I was all set with 3 bottles, so I kept at it, alone. I was making progress on a group of 8 or so in the distance. I turned onto a sector of gravel and watched them crest a hill. I crested the hill, and they were no where to be seen. In the distance, I saw a rider stopped. So I went all the way too him. He did not know the course either. Just as we were laughing about this, we see the next group of 20 or so make a turn North just past the crest of the hill! We back track and chase. Its hard to paint turn arrows on dirt I guess, and there was no sign. My Garmin was not being much help either. I missed a few more turns, passed a few single riders and smaller groups and eventually got caught by 2 if the 5 guys I was with before the rest stop. They wanted to know how I made it through Lovers Lane. I still had an arm covered with cockleburs to show for my efforts. I told them that they were seriously messing with my aero, and that all I had. We had fun for the next 10 miles to the finish.

At the fire house, the crew had lots of options, brats being the most important in Wisconsin. Everyone was just throwing them 10s and 20s instead of the prices. This led to a good donation amount. I came to the food line just in time to here the 4 guys in front of me asking did you see what happened to "that guy" to each other? Yep, "that guy" was me. We had a fun talk. I was talking to another few guys later, about tire choices. Nice talk. As I am riding away I hear one of them say,"That guy is nuts!" Nuts, but I sure had a fun ride! I think I finished in the top 15% or so. Not bad considering my fitness and the challenges.

So what did I learn? I don't know that it would have helped much on Lovers Lane, but on the other sections I would have been faster on even fatter tires, with less air. I had to back off the power several times due to fishtailing, or my front wheel bouncing around too much. I had mine at 60f/55r. Now knowing that the pinch flat hazard was not big, I could have gone lower with the air. I really want to get up to about a 40mm tire. Word is that is the fast size for Dirty Kanza/DKXL and a few other events. That is not going to fit my CA3 without voiding the warranty by removing the whole area around the rear brake bolt, and a different fork that is going to elevate the front of the bike a bit. I am still convinced that if its dry, tread on the tires is not required. Hoping to try some 36c Challenge Strada Bianca's or something bigger soon. Here is a review of them and the front tire I was using. I'll be looking for something as fast as a Compass Pass tire, but more puncture proof. For a frame and fork, if I want to keep running 700c tires, and I want to because they will roll better, I need to look beyond Bacchetta.

Addendum 5/25/18: Just realized that BelgianWerkx who puts on this ride is also a sponsor of the JBVCoaching CX team! Yes, I am a bit disconnected, from CX.

Tuesday, May 1, 2018

High performance U-bars, stem and riser for recumbents.

Let me make a few prefaces first. If you are looking for handlebars that are adjustable in length and width and grip flare angle, consider Schlitter J-bars as seen on the Schlitter Encore, available from Jacquie and John Schitter at Schlitter Bike. These bars a very easily folded for a travel bike too. Do keep in mind that grip flare angle will be a function of width. If you just want bars with adjustable length, consider Rans 3Way Bars, available from Jerrell Nichols and team at RANS. Both these bars make great sizing tools to figure out what size custom bar you need too. You can even use the RANS bar with my suggested stem and riser below. If you are very concerned with weight, both bars are pretty light. both are easier to shop for and set up as well. I believe many riders would enjoy their riding more with a focus on bike fit and handling though. 

The above are simpler to set up than what I describe below. But keep in mind, you can have a shop do this for you too. 

This configuration has a range of applicability with regards to boom length. If you have a boom of 12.5" (current Medium Bacchetta), you can also use the current Bacchetta 3 Piece Riser with a 120-140mm off the shelf stem to get your bars maximally low. It will not be adjustable for reach, only height, but it will weigh less. The cost will be the same or more depending on how much you spend on the off the shelf stem. If your boom is even shorter, just use a shorter off the shelf stem. On the other end of the spectrum the stem angle of +35 degrees means that as the boom get longer than about 17", and the frame deviates from a stick, you may not be able to get the bars low enough with this set up. I think a Pelso Brevet L will work. If you are choosing a geometry for a new Carbent, this is something to keep in mind as well. Reducing effective tiller is always good, until you need a $1000 stem to locate your bars!

This will not work on Metabikes, as there is too much effective S in the frame, and the boom is too long. 

If you have great visibility over the bars, your arms are relaxed when you can reach the brake and shift levers, your hands are in line with your shoulder, your bars and short and stiff enough, and you are happy with your seat recline, this is not something that will make a big improvement to your riding experience. In fact, if you are more upright, you may not want maximally low bars, as it will put your hands well below your shoulders. 

This combination of parts suggested below will achieve significantly greater rigidity than the bars currently used on many recumbents, including the options above, and allow you to recline as far as you wish and still have relaxed arms, and allow you to get the bars maximally low for the best forward vision without hitting your feet. The key is using 31.8mm tubing rather than 22.2mm for the bars, and an adjustable length stem. Many riders are looking through their bars, and reaching too far to hold onto them as they recline more. Sadly to recline more you have to use a shorter stem, which means the bars go higher! I have seen many recumbent riders challenged by flex between the hand and the front wheel. On many bikes this flexibility is in the bars, but some stems and forks and frames can be contributors too. This flex causes hand shake at higher speeds and power levels, lack of control during hard cornering, and a general lack of oneness and ease when riding. This becomes a bigger factor on rough roads (or worse yet gravel), technical descents, fast group rides, and even hard solo efforts on smooth ground for some riders. Even the most relaxed and skilled riders can be affected by this. Whats to follow fixes all that, and more. 

Here we go with the pieces!!

First you need a Control Tech Stoker Stem. This will allow you to adjust both the height and the fore-aft position of your bars for maximum forward visibility and without hitting your feet. This stem is not light. It is rigid, and very reliable. It comes in several clamp diameters at both ends. You need the 31.6mm seat post diameter (that goes on your riser), and either the 25.4mm bar clamp diameter (if you are using Bacchetta stock bars or most others), or 31.8mm bar clamp (If you go with custom Power On Cycling bar that I recommend). If you only want to buy this stem once, go for the 31.8 bar clamp as you can shim a 25.4mm bar with Wheels Manufacturing Handlebar Shims. The 31.8mm bar allows you to put your cables inside the bar.  A big shout out to Mark Power, as without his custom bars, we would be a lot more limited! He can make U-bars for Lowracers too.

For length mine is at about 200mm, so the short one is fine. I am on a L frame (14") boom, and 170 cranks. On an M frame (12.5") boom, I would only use this stem if you are a very toe down peddler, or are running 155mm cranks or shorter, or some combination of those, or you are willing cut some length off both stem pieces to get it down to about 145mm with 170mm cranks. Also, bar width at the front has an effect on how long you can run the stem without bumping your foot on the bar in turns. My U bar has some V to it so I can get my bars the lowest possible, and fit it in my car easier. My bar is about 16" wide in front and 19" where my hands are. This is why an adjustable stem is so cool. No matter what your bars, pedaling style, foot size, or crank length, you can get your bars maximally low. 

Here are the dimensions of my bars, and this is what Mark will ask you for as well. 
  1. Handlebar wall thickness (065" recommended for .875" OD  HB's) 31.8mm, 22.2 grip
  2. Outside of HB width at end of horizontal (~18.5", narrow spec Aero)  19"   
  3. Outside of HB width just after aft bend (~17.5", narrow spec Aero)   16"  
  4. Front center of HB's to center of grip zone bend (horizontal HB reach) 10.5"
  5. Grip zone angle (40 degrees Bacchetta stock) 40 degrees
  6. Grip zone length, end of grip zone to center of bend 7"
  7. Grip zone boring requirement and length (if bar ends are used) reamed for Sram/Shimano bar ends. 

You will need to figure out yours based on what you currently use, how much more you want to recline and how much forward extension your current stem has. This should help if you are on a Bacchetta: Dimensions of all Bacchetta Risers/Stems. On any other bike, just measure from the center of the steering axis to the center of the bars, with the tape measure or ruler parallel to the frame tube. You want the bars to be wide enough that you have enough steering room for steep climbs, and corrections in gravel. An inch between you hands and thighs is enough for most. You can add some V to your bars like I have by making the front narrower than the grip area, but you must have clearance for your calves, and if you are bowlegged at all that will be a factor as well. Keep in mind extra clearance for tights or rain pants if needed. 31.8mm bars are not very bendable, so you want to order them right. As a rough guide, if you are on a Bacchetta L frame, your new stem will have about 165mm of reach once you adjust it. Keep in mind that even if you change to a different boom length frame, as long as recline stays the same, your bars do not change, only your stem. Bar dimensions are only a function of your body and its position on the bike. Also, people hold the grips in different spots to get comfy, so you do not have to be accurate to the tenth of an inch on the length of the bars. 

For the riser tube, you need something with an ID of 1 1/8" (28.6mm) that slides snugly down your steerer tube. The wall thickness needs to be 1/16" so the OD is 1 1/4". You can just use an old one piece Bacchetta riser (either reach), or lower section of a Bacchetta 2 or 3 piece stem, and cut off the top, like I did at first.

..or get a piece of carbon tubing from Dana at Bent Up Cycles (cleanly cut and slotted on a water-cooled saw), or Rock West Composites, which I did later. Chuck your BFT, and put a star fangled nut (for aluminum lined steerer tubes) or an expander nut (for full carbon steerers) down the steerer and add a conventional top cap and bolt for headset adjustment.Headset Cap and Bolt

If you are doing this to a bike with a 1" steerer tube, you need a riser tube with an ID of 1" (25.4mm) and an OD of ~31.8mm. Here is one I found. You will also want a 1" top cap for the headset. Here is one of those.

For the riser clamp to the steerer, I first went with Bacchetta dual bolt clamp, which you can see in the pic above. Bacchetta Double Bolt Riser Clamp
Now I use the single bolt clamp they used on their newer 2 and 3 piece stems. Never had a slippage problem and it's lighter and cleaner looking.

Also, since the 31.6mm stem clamp to the riser is actually 0.2mm too small, its good do have a Cal-Van spreader tool to use, rather than twisting a big screwdriver to spread it. 

I don't not see them on Cal-Vans site, but have seen them in auto parts stores recently. I believe they were designed for R&R of springs in automotive drum brakes.

Having put stiffer bars on several personal bikes (Velokraft Nocoms, Bacchettas, and Carbents), I have noticed that it allows me to now feel the next largest source of flex. In the case of the Nocom, it was the fork, and nothing could be done. On the other 2, I was now much more cognizant of the affect of tire pressure and sidewall flex. It also made me wish for a frame with a tapered steerer and a thru-axle fork, just so I could see if it could be even better. 

The only thing I might have done differently on this bike is to make the bar grips and inch longer and the length of the bars a little less, so my hands would be in line with my shoulders with the bars level. 

Contact me at Jim@JBVCoaching if you have any questions, need a fitting, or a coach!