Search found 99 matches

by Oceanic
16 Jun 2022, 10:21pm
Forum: Bikes & Bits – Technical section
Topic: Plastic inner tubes.
Replies: 18
Views: 2176

Re: Plastic inner tubes.

I’ve been using Schwalbe Aerothan tubes for over a year on my best bike.

I wanted the low rolling resistance of latex tubes, but without the risk of a latex tube over heating and exploding on a long descent.

I’ve had one pinch flat caused by hitting a huge pot hole on a group ride (rider in front didn’t call it out).

I tried a self adhesive patch (I think it was a Tubolito one, but not 100% sure) didn’t work and I gave up and bought another tube.

I would not hesitate to buy another set of Aerothan tubes if something happened to my present set.
by Oceanic
14 Apr 2021, 9:34pm
Forum: Bikes & Bits – Technical section
Topic: How essential is PTFE tape for valve extenders?
Replies: 8
Views: 670

Re: How essential is PTFE tape for valve extenders?

I‘m riding around on Schwalbe Aerothan tubes with valve extenders and no PTFE tape.

The valve extenders have a rubber gasket and I added a bit of vibra-tite threadlock.

The ‘valve tubes‘ on the Aerothan inner tubes are plastic so I didn’t want to use normal threadlock.
by Oceanic
13 Mar 2021, 8:00pm
Forum: Bikes & Bits – Technical section
Topic: Unable to remove HT2 bottom bracket in carbon frame
Replies: 66
Views: 2690

Re: Unable to remove HT2 bottom bracket in carbon frame

This is the problem with the stupid modern trend towards threaded bottom brackets. You never would have had this problem a few years ago when push fit bottom brackets were more common.

(To be read with a heavy dose of irony).
by Oceanic
8 Mar 2021, 8:28pm
Forum: Bikes & Bits – Technical section
Topic: GRX chainset.
Replies: 20
Views: 2515

Re: GRX chainset.

Barry and Janet wil wrote: She never misses a gear, happily swaps rings so life is rosy.


That’s good to know, thanks. I suggested to a friend last week that he should buy those chain rings and I was a bit concerned that if the shifting turns out to be less than ideal I might get the blame.
by Oceanic
8 Mar 2021, 12:55pm
Forum: Bikes & Bits – Technical section
Topic: 1x11 setup question
Replies: 21
Views: 1309

Re: 1x11 setup question

Brucey wrote:So if a rider 'chose' to ride 1x in the worlds it might be that he genuinely did so. However it is just as likely that he was coerced into doing so and agreed because it was made worth his while and realistically (eg because of national federation team orders) he wasn't in a position to win anyway.

cheers


Magnus Sheffield also used 1x in the World Champs in Yorkshire (in the Junior road race).

He was sponsored by 3T at the time, so I’m fairly sure it wasn’t entirely his own choice, it didn’t stop him finishing second.

I’m fairly sure that Junior gears are limited even at the World Champs, but in some ways I’m more interested in what works for the Juniors, as the amount of power I produce is so far away from what the adult pros produce.
by Oceanic
8 Mar 2021, 10:10am
Forum: Bikes & Bits – Technical section
Topic: 1x11 setup question
Replies: 21
Views: 1309

Re: 1x11 setup question

Brucey wrote: The experience of 1x professional road rider 'guinea pigs' has been that they were at a significant disadvantage at critical moments in races because of their gearing system.

cheers


Baulke Mollema and Mads Pederson have both chosen to ride 1x in some races despite their team mates riding 2x (Baulke Mollema used 1x in the World Champs in Harrogate). It’s not suitable for all pro races, Aqua Blue won at least one race on 1x, but objected to being forced to use it on stages where it wasn’t suitable.

(Edited as I removed a long rambling paragraph from my answer that wasn’t really relevant).
by Oceanic
7 Mar 2021, 11:06pm
Forum: Bikes & Bits – Technical section
Topic: GRX chainset.
Replies: 20
Views: 2515

Re: GRX chainset.

Barry and Janet wil wrote: I've gone for 46/30 oval rings from Absolute Black, largely because they fit the current 8000 cranks.


How is the shifting compared to the Ultegra chainrings?
by Oceanic
7 Mar 2021, 9:52pm
Forum: Bikes & Bits – Technical section
Topic: 1x11 setup question
Replies: 21
Views: 1309

Re: 1x11 setup question

Jdsk wrote:Are those the absolute power or the difference in power between the comparators?

Thanks

Jonathan


The difference between the two systems as quoted in the studies I linked to.

The 5W difference for aero drag sounds high to me, so I wonder if it relates to a tt frame which channels the air flow past the front mech and over a disk wheel. I think I’ve heard 2W quoted as the figure for aero drag reduction when using 1x on an aero road bike, but I’m not sure where I read it.

Similarly the 5W increase in friction drag relates to the use of a 10t sprocket. I have one on my bike, but I rarely use it.
by Oceanic
7 Mar 2021, 8:19pm
Forum: Bikes & Bits – Technical section
Topic: 1x11 setup question
Replies: 21
Views: 1309

Re: 1x11 setup question

Brucey wrote:
2x is measurably more efficient than 1x, to an extent that means that the 2x setup is faster up all but the steepest hills.

cheers


The frictional losses in 1x drive trains due to cross chaining are tiny when compared to 2x (about 0.3W). The frictional losses due to 1x using a smaller sprocket with a smaller chainring are larger, but they only become significant when in the highest gears (about 5W).

When the rider is using the highest gears he/she is presumably travelling at a significant speed and therefore the aerodynamic advantages of 1x come in to play (about 5W).

So for most 1x setups the small frictional losses are cancelled out by the small aero advantages.

Source
https://ride.diamondback.com/friction-p ... rivetrains
https://www.velonews.com/gear/gear-issu ... ivetrains/
by Oceanic
12 Sep 2020, 4:18pm
Forum: Bikes & Bits – Technical section
Topic: Wahoo to strava: Heart Rate Monitor
Replies: 11
Views: 1285

Re: Wahoo to strava: Heart Rate Monitor

I’m fairly sure that Strava has removed support for heart rate monitors when recording rides through the app. So pairing your HRM with your head unit will enable you to record more data, not less.
by Oceanic
2 Jul 2020, 9:29am
Forum: Bikes & Bits – Technical section
Topic: Direct mount brakes, better, worse?
Replies: 13
Views: 1063

Re: Direct mount brakes, better, worse?

25c Tyres (which measure 24mm) inside SRAM direct mount brakes. Seems that there is more room than I remembered.
by Oceanic
2 Jul 2020, 8:39am
Forum: Bikes & Bits – Technical section
Topic: Direct mount brakes, better, worse?
Replies: 13
Views: 1063

Re: Direct mount brakes, better, worse?

To answer the original question...

I found a small, but noticeable difference in stopping power when I swapped from a frame with SRAM Force rim brakes to SRAM S Series direct mount rim brakes.

My bike has no mudguard mounts, but I would be surprised if you could fit any more than 23c tyres inside the SRAM direct mount calipers when using mudguards.
by Oceanic
2 Jul 2020, 8:12am
Forum: Bikes & Bits – Technical section
Topic: Carbon frames for Mamils with high handlebars.
Replies: 67
Views: 4069

Re: Carbon frames for Mamils with high handlebars.

PH wrote:
I didn't read it all, but he dismisses your theory about weight distribution right at the start


Later in the article he goes on to say this...
If a person buys this same bike and sets it up in a more upright position because his physical limitations do not allow him to ride like a pro. They should then accept the limitations in the design of the bike which after all is designed as a racing bicycle, and if it develops a speed wobble at 45 mph. the rider should consider either a change of position or keep the speed below 45.


I’m not suggesting that anyone with a bad back should try to ride in a low position, but I am asking which bikes have been designed for the, seemingly large, group of riders who want an upright position, but still want to ride a bike that is superficially similar to a racing bike.
by Oceanic
1 Jul 2020, 10:33pm
Forum: Bikes & Bits – Technical section
Topic: Carbon frames for Mamils with high handlebars.
Replies: 67
Views: 4069

Re: Carbon frames for Mamils with high handlebars.

kylecycler wrote: although weight distribution is another factor to do with shimmy. It's a mysterious business, though, so let's not go there, at least not in this thread!


I couldn’t help myself, I had to...

http://davesbikeblog.squarespace.com/bl ... ution.html

-Moulton‘s explanation of how raising the bars (on a bike designed for racing) can cause speed wobble.
by Oceanic
1 Jul 2020, 5:51pm
Forum: Bikes & Bits – Technical section
Topic: Carbon frames for Mamils with high handlebars.
Replies: 67
Views: 4069

Re: Carbon frames for Mamils with high handlebars.

A1anP wrote:. If the handling of the bike has been affected ... then I haven't been aware of it, and it hasn't spoiled my enjoyment.


There was some discussion on the Marginal Gains podcast about how some riders are highly sensitive to changes in the way a bike handles, and others are entirely oblivious. Their main point was that it is better to be in the oblivious group! They also discussed the fact that if a rider is convinced that there should be something wrong with the way a bike handles, they will perceive that problem, even if it's not there.