Bicycle Tech/Gear Discussion Thread

Mar 24, 2014 at 09:31 PM

I had play on my gxp rival cranks all last year. During the off season I cleaned and greased everything up and torqued down the crank bolt tight. No more play and smooth spinning - didn't even install a new BB. I didn't use a torque wrench at the time, just a big ass allen key and all the power my puny arms could muster.

When I first installed, I used a torque wrench and followed the SRAM instructions but there was play . Go figure.

twoyacks

Mar 24, 2014 at 09:36 PM

well...I'm going to install my old Rival drive side arm and tighten her down to see if the problem is that arm or the spindle. I tried putting on the original-non Stages arm that came with the new crankset and same ammount of play was there. If my old rival crank shows no play...then it may be a warranty issue with the new crank not being to spec. OR the bb is fucked some how....

twoyacks

Mar 24, 2014 at 10:02 PM

Old Rival crank exhibits the same play issues....BB must be shot somehow. Will likely order a King

twoyacks

Mar 24, 2014 at 10:54 PM

Sweet relief....Ride Brooklyn is going to order a Chris King bb and they will install it....

twoyacks

Mar 24, 2014 at 11:08 PM

Oh...and yes I did use my cat III discount...hells yeah i did !!!!

twoyacks

Mar 25, 2014 at 12:36 AM

This thing gives me an "OOOhhhh" face...

CKBBRSR-BK-1.jpeg

Wes Tillman

Mar 25, 2014 at 02:29 PM

anyone race on these? http://www.competitivecyclist.com/vittoria-diamante-pro-lite-ii-tire

I've been racing on mavic powerlink / griplinks for a while and I'm looking to switch it up. I'm a noob when it comes to vittoria so any input is appreciated.

dstokes

Mar 25, 2014 at 04:25 PM

Vittoria tires are great. The gold standard are the Open Corsa CX for racing (either tubular or clincher). I have also used Rubino tires for training and they have very long life. I have no experience with these diamante tires. The thread count looks good (220) and I generally like slicks. But I am a little worried about the very light weight (170g compared to 210 for Open Corsa). The normal Diamante Pro are also 210. So it seems that these Diamante 'Pro Lite' may be intended for weight weenies. This usually means shorter life and more prone to punctures.

David Yang

Mar 25, 2014 at 04:29 PM

@Wes - Conti GP4000s on sale:

http://www.competitivecyclist.com/continental-grand-prix-4000s-tire-con0036

twoyacks

Mar 25, 2014 at 04:34 PM

I have found the Vittoria's to have a much nicer ride than the Conti's...The Open Corsa's with latex tubes anyway

David Yang

Mar 25, 2014 at 04:41 PM

I switched from Rubino Pro IIs to the GP4000s and think the Contis roll & grip better and last a bit longer. Anecdotal, but what I observed.

Jeffrey White

Mar 25, 2014 at 09:21 PM

I have never ridden a better feeling tire than the Vittoria Corsa CX tubulars, and I've tried the Conti tubulars. I currently have Conti Sprinters (with a Gatorskin breaker!) for early season park races and Battenkill. Once I get to crit season, the Vittorias go on.

Jeff Apruzzese

Mar 25, 2014 at 10:09 PM

I've been racing on the Vittoria CX III clinchers with latex tubes for this early season start, and I love them. They have a really good grip, and the latex tubes give it a very tubular like feel.

twoyacks

Mar 25, 2014 at 10:30 PM

They are in a word...sublime

mperlberg

Mar 26, 2014 at 12:57 AM

Hey Team -

What's the best lightweight tube to run with 25m clincher race tires?

It seems like some butyl tubes are lighter than latex. It also seems like there are limited options in latex for 25m tires. I know latex supposedly has a better ride quality.

So, tell me what to buy. That's it.

Joaquin

Mar 26, 2014 at 01:06 AM

@mperlberg, both Vittoria and Challenge produce latex tubes in 25m. Below are Amazon links:

http://www.amazon.com/Vittoria-Latex-Tube-Color-700x19/dp/B003M3R9ZQ/ref=sr_1_1?ie=UTF8&qid=1395795656&sr=8-1&keywords=vittoria+latex+tube+25

http://www.amazon.com/Challenge-Superlite-Latex-Corsa-Tube/dp/B003CO2QW6/ref=sr_1_fkmr1_1?ie=UTF8&qid=1395795932&sr=8-1-fkmr1&keywords=challenge+latex+tube+25

The Vittoria is a claimed 75 g, which is pretty light. Don't know what the weight of the butyl tube you're looking at is. FWIW, if true that latex reduces rolling resistance, then that might be worth more than saving a few grams.

mperlberg

Mar 26, 2014 at 01:14 AM

Thanks!

Challenge might be the way to go. I'm going to see what Ride Brooklyn can get them for... they claim them at 57 grams. Wow.

http://worldclasscycles.com/tubes_adhesives_cart.htm

dstokes

Mar 26, 2014 at 01:31 AM

Wait. 25mm TUBES? Last I heard, tubes had a range (like 18-23 or 25-28). I feel quite confident that you could use the 18-23 with a 25mm tire. In fact, I've used 18-23 with a 'cross tire, which would be something like 32. Sure, they are a little stretched out and more prone to pinch flats, but I think the 18-23 in a 25mm tire would be fine. So I am highly dubious of the idea of a tube specific for a 25mm tire. Latex vs butyl is another matter altogether.

twoyacks

Mar 26, 2014 at 01:31 AM

http://www.probikekit.com/bicycle-inner-tubes/michelin-aircomp-latex-road-inner-tube-700-x-22-23mm/10782220.html

Michelin Aircomp Latex is what you are after. I have been riding them for about 2 years now on 25mm tires with wide rims. No problems riding them at 90 psi. Latex doesn't pinch flat like butyl. If latex broke when you pinched it...the world population would reach its tipping point.

51Z9147ZPVL.jpg

mperlberg

Mar 26, 2014 at 08:26 PM

I read a few places that it is not advisable with latex tubes to ride them over their width limit.

I have no personal experience with the situation. You and yacks seem comfortable living on the edge.

dstokes

Mar 26, 2014 at 08:50 PM

I was talking about butyl. I'm too cheap to buy latex tubes.

JohnMalcolmson

Mar 26, 2014 at 09:57 PM

Latex tubes:
- easy to mess up on install and pinch them between bead and rim (they're a bit more delicate)
- latex perishes at some point
- have to check your rim tape is perfect, some cloth tapes just don't play well
- good for race wheels, PITA for training because inflation

twoyacks

Mar 26, 2014 at 10:46 PM

Alls that's required during installation is some powder...inflate half way..then push in tire with thumbs and make sure no green tube is creeping out...then inflate all the way. For training any powder will do. On race day I bust out the high zoot shit...

anti-monkey-butt-powder-705490.jpg

neilx

Mar 26, 2014 at 11:21 PM

I use Vintage Midnight Tussy Powder

P.S. Malcolmson has ham hands.

JohnMalcolmson said:

Latex tubes:
- easy to mess up on install and pinch them between bead and rim (they're a bit more delicate)

$_12.JPG

ian ellis

Mar 27, 2014 at 01:31 AM

I trust you plan to use these latex tubes with some great race tires (Vittoria CX, CG, Veloflex, schwalbe ZLX).

Also do beware that latex tubes are more susceptible to heat build up. I've had them burst in carbon clinchers (themselves a solution to a problem that doesn't exist) here in NY. However, I have also had latex tubes burst in factory shimano alloy rims (the type for clincher/tubeless where there are no spoke holes and no need for rim tape). Here they burst descending in the Dolomites. I suspect the heat build up was too much for the latex tubes.

mugwump

Mar 27, 2014 at 02:07 AM

ian ellis said:

I trust you plan to use these latex tubes with some great race tires (Vittoria CX, CG, Veloflex, schwalbe ZLX).

Also do beware that latex tubes are more susceptible to heat build up. I've had them burst in carbon clinchers (themselves a solution to a problem that doesn't exist) here in NY. However, I have also had latex tubes burst in factory shimano alloy rims (the type for clincher/tubeless where there are no spoke holes and no need for rim tape). Here they burst descending in the Dolomites. I suspect the heat build up was too much for the latex tubes.

Ian,

You're going to have to have something more than personal experience to back this up. Basically, the issue isn't the tube, but the wall of the carbon clincher. 100psi exerts the same force whether latex or butyl. And the blowout is from the wall softening in heat. If there's a difference it's the the greater elasticity of latex means it expands faster when there's nothing holding it back.

And here, from Zinn

http://velonews.competitor.com/2013/04/bikes-and-tech/technical-faq/tech-faq-all-about-carbon-clinchers_284201

mugwump

Mar 27, 2014 at 02:13 AM

JohnMalcolmson said:

Latex tubes:
- easy to mess up on install and pinch them between bead and rim (they're a bit more delicate)
- latex perishes at some point
- have to check your rim tape is perfect, some cloth tapes just don't play well
- good for race wheels, PITA for training because inflation

I'm with yacks on Latex. Talcum powder is essential.

Yes, Latex perishes, but so, too, does Butyl. If Latex is inside a tire or inside a bag, preferably with talcum powder on it,it will last a long time.

Not sure I'm believing the rim tape, as I've used ultralight Rox, regular plastic, and thin Zipp. Not sure why it would not play well--other than lack of talc.

The "expanding beyond recommended size" issue is one I've heard from Michelin and Vittoria. I'm not sure I believe they're doing anything more than covering their asses. At the same time, latex tubes are expensive and I'd rather not find out.

Theoretically, a latex tube rolls better than a butyl at the same weight because of the elasticity. Think of it in the way that a tire with a greater thread countn rolls better than one with a lower.

Here's an article from Schwalbe. (I wouldn't take it as gospel though)

http://www.schwalbetires.com/tech_info/tire_tube

dstokes

Mar 27, 2014 at 02:23 AM

mugwump said:
Basically, the issue isn't the tube, but the wall of the carbon clincher. 100psi exerts the same force whether latex or butyl. And the blowout is from the wall softening in heat. If there's a difference it's the the greater elasticity of latex means it expands faster when there's nothing holdon'tding it back.

This is uncharacteristically incomprehensible. First, any heat buildup will increase the pressure in the tube above 100 psi (this is the ideal gas law where P=V*T). Second, although butyl and latex tubes may experience the same pressure , within the tire, they will behave differently when stretched (same as carbon fiber vs. Titanium). Third, Ian refers to Al rims, which are not going to get soft under any conditions that we will be able to endure.

I'll check out Zinn. Maybe he'll clear everything up for me.

mattie davitt

Mar 27, 2014 at 02:32 AM

AS: You mentioned latex tubes as well. What magnitude of savings do you get with them? Are they the best examples of a cheap and unsexy upgrade that produces big gains?

JP: Yes, latex is probably the best bang for the buck upgrade you can ever make to any of your bikes. They are definitely more labor intensive to install than butyl, and you have to pump them up every day...but you can save 3-5 watts per wheel(!) compared to butyl. At the moment, tubeless is getting better, but still nobody has a tubeless system as efficient as a high quality standard tire with latex inner tube.

Putting it in perspective, that $20 latex tube at minimum would be worth maybe 3 watts in a front wheel compared to $1000 for the best ceramic bearings which might get you 0.8-1 watt for a wheelset upgrade.

dstokes

Mar 27, 2014 at 02:38 AM

That sounds very convincing.