MarkWW

It's a hard question to answer. Under normal conditions, supposing the bike was engineered and built properly, it shouldn't have a lifetime. That said, I remember reading a story about a prototype carbon frame that a major manufacturer was testing. It was super stiff, super responsive, but one day while the tester was sitting on the top tube at a light, it cracked in half. They didn't account for that force in the carbon layup.

Crashing is a different story. That would require more of a case by case analysis. I've been told the Felt TK1 sprint was designed with a different layup than the endurance so that it could survive multiple crashes. In general, though, I would say carbon fiber is more resilient than most people think. The issue really becomes a mental one. Without testing the frame each time, how are you really sure your equipment is fine? Doubting equipment can destroy your performance.

The first time I went up to Forest City, I had my bike with carbon handlebars. Going fast through those steep turns feeling the G forces, I was really starting to wonder if maybe I had knocked those bars around too many times, and I found myself letting off the gas just a little.

Baby Puke

Anybody ever had their carbon frame/wheels/components x-rayed? What was your experience and what did it cost? Just curious about this as a forum member had a minor get-off yesterday and it made me think about my gear, some of which might getting on a bit in age, depending what you believe as far as how long stuff will last. Until last year I'd been riding a disc that must have been built in the 90's and had taken multiple knocks just in the relatively short time I'd owned it.

carleton

Take a coin and tap around your wheel and listen for a different tone.

Jaytron

Anyone know if the alpina bars have an AL core, or if they're all carbon? I took a spill and the bars took some beating and I'm not sure if I should still use them.

Baby Puke

J you should post a picture of the damage here. I still think it's pretty minor, but get some more expert eyes than mine on it.

Huffandstuff

This one goes out to you Alpenrose fellas.

What's a good clincher tire to use?

I saw Brian Ratliff say vittoria corsa cx tires are common forr Alpenrose but I'm just wondering if it not being a tubular changes the choices.

Lew.

Regarding the x-raying carbon - would the fibre/layup/damage really show on an x-ray? (I doubt it, but I've only ever studied x-rays into medical uses, and even that was a low level of education).

Certainly wasn't something I knew people had done to carbon, I thought metal was 'checked' with ultrasounds, so maybe could show defects in carbon?... Going out on a limb, I'm probably wrong...

saba

Dear Carleton,
Cervelo T1 110 Thomson x4 zero rise stem 1mm spacer currently under the stem. I race sprint and mass start. Why should I flip my stem? Fit measurements available.

Baby Puke

My circa '90 Silca track pump has finally died. What do you guys recommend as a replacement? I've got a Hirame chuck that will be swapped over, so most concerned about the pump itself. Thanks.

bigfred 

How can you "kill" a Silca? The leather cup is replacable. The handle is replacable. The hose is replacable. I'm not sure of a source for the screw in top cap, but, surely those are available some where?

Denting the barrel is the only thing that comes to my mind as a justifiable reason for retirement:-)

carleton

Sorry. I missed this.

Flip/flop stems are useful because if you have any angle other than 0 degrees, you have 2 rise/reach options.

You have to identify a problem before you look for solutions. Right now, flipping your stem is a solution to an undefined problem.

I use a metal-chambered Specialized Air Tool HP pump. It goes up to or over 200PSI (I can't recall the exact number). I've had mine since 2010 with no issues. I use the stock valve, but you can cut it off and use whatever you choose.

They are MSRP $50 and you can probably find one at a local Specialized shop. Just make sure that it is the "HP" (high pressure) model and not the more popular standard model.

https://www.specialized.com/us/en/ftb...-hp-floor-pump

EDIT: The website says "Up to 180psi". Maybe they have changed since 2010. If you use 180PSI or less, this is a good option. Getting parts/service would be easy, too.

Baby Puke

The plastic spacer that sits on top of the leather washer is cracked and allows the leather washer to deform. I've not been able to find a source for this part, so I guess that's how you kill a Silca. RIP, old friend.

Quinn8it

I am a big fan of the Lezyne pumps.

Over 200psi

the included connector threads on to the valve stem (presta or shrader)
which I like because it allows me to not add valve extensions on Deep-V depth rims- just enough of the valve sticks out to thread it on..

There is also a disc chuck that screws on- and the rubber O-rings inside are tight enough that it will stay on a valve stem without holding it in place most of the time..

This is probably not the pump if you want to keep the Japanese disc chuck.. But that chuck is fitting less and less disc these days (wouldn't work on my last 2 disc)

bigfred 

If you simply "want" a new pump, then by all means, you have an appropriate reason.

But, if you would like to save your old track pump, I would recommend that looking at what McMaster-Carr has to offer might yield a piece of material of the correct dimensions to replace the channeled plastic spacer that supports leather washer.

Just a thought.

carleton

If you really want to get fancy, get one of these:




It goes up to 200PSI. You'll have to cut that head off and put on one that will fit presta valves.

My teammate in Atlanta had one. It was very handy, especially for pumping up discs with one hand. Useful for the ladies who have a hard time getting high PSIs using normal pumps.

It is $45 not including the battery. If you already have Craftsman battery power tools, then you may already have one that will work. Otherwise, the battery and charger is an extra $75.

https://www.craftsman.com/craftsman-c...&blockType=G14

Baby Puke

Big Fred, I would like to keep this pump forever, but that piece is threaded, vented, and of a specific length and diameter. I just need a pump, and I do not have my own machine shop.

Too fancy for me, Carleton!

Soil_Sampler

brass washer.

bigfred 

Or stainless, or, just about anything.

It's not a precission part nor a precission piece of equipment.

Cantrackie

I like it, my problem is pumping the tires is calculated into the training program.

Quinn8it

These things sorta suck IMHO... First off they can't pump a tire up from zero- so you have to have a normal pump nearby.. So now you travel with 2 pumps.. The one that works- and the stupid electric one you paid too much money for..

slindell

I have an earlier version of this https://www.sears.com/craftsman-12v-p...2&blockType=G2 (12 volt battery powered portable compressor) that I got for 10$, current one is 35$. It lives in the back of the truck and only needs to be charged a couple of times over the season. It is noisy, a bit too heavy to travel but does 180-200 psi ok and makes filling the disk a far easier task.

zizou

Tactical tip for first time sprinter

Basically i am an enduro with a decent sprint. But that is relatively speaking - I'm certainly no match for a proper sprinter.

Anyway i will be doing a sprint ladder this week which will consist of match sprints (likely with 3 on the track rather than 2) and im going to be up against sprinters at some point. I would estimate these guys will be between 2-3 seconds faster than me on a flying 200. Are there any tactics that can level things up a little? Is it a case of going for a long one and hoping to hold on or is there anything more subtle than that? Or are enduros simply an irrelevence in a 3 lap race?

Baby Puke

I will offer my humble advice: In a three-up, try not to be last guy, take the front early if necessary. From the front you can control the pace, do not go all out, but raise the pace with 1 to go, when you do go all-out, just go fast enough to keep the #2 guy on your hip, this will force #3 to go high to pass which is difficult. Best spot is #2 if you can get it, leave some space to run into #1 guy's draft and watch #3 so you don't get boxed in. You can play with positioning, force #3 to go high.

queerpunk

3-up sprints are pretty cool and definitely have different tactics than 2-up sprints. My advice would be to try to keep things slow, and be the first person to attack - from far out. Often this is a terrible tactic but in a 3-up sprint against better sprinter, you want the two others to look at each other and think "no, YOU chase." A second or two of hesitation on their end can win you the race.

VanceMac

Apologies, but unless you are missing a decimal point, there are no tactics that will help in that scenario. That is an ENORMOUS delta. If I were up against someone even just 1 full second faster, I would go IMMEDIATELY from the gun... and at least make him hurt.