Time Trial / Time Trialling / TT

Here's some West London events for the West is Best crew...
http://www.willesdencyclingclub.co.uk/calendar/west-london-combine/

Anyone interested in my old frame, tiny head tube so good for a fixed tt set up, 56 x 56 felt tk3
http://www.lfgss.com/conversations/260213/#comment12096163
175 quid

http://endurancesportswire.com/falco-introduces-possibly-the-worlds-first-tri-specific-wide-narrow-single-ring/

What's the go with this narrow wide thing?

What's the go with this narrow wide thing?

Reduces the chance of chain drop on 1×n drivetrains, although MTBers seem to need clutched RDs to make it safe to dispense with any kind of chain guide.

Of course, we all used to use single chainrings in the olden days without recourse to any gadgetry, and you'd have thought that somebody would have tried to flog us something over that half century if dropping chains in TTs was really an issue.

The discussion on TTF suggests that the modern need for extra bits to hold the chain on is possibly related to the increased complexity of modern chainrings (ramps, pins etc.), the modern flexibility of chains and the wider angles caused by shorter chain-stays and 10/11 speed cassettes.

Of course I'm too young to remember the olden days so I wouldn't know :-)

Is it not an issue? I want to go single ring but worry about unshipping the chain mid race.

I honestly can't remember a single dropped chain in about a decade of TTing on 1×n (for n>1), although I'm pretty sure my dad dropped a chain at least once between 1969 and whenever he got a front dérailleur, i.e. about 2006. In the olden days, all the chainring teeth were full-sized, we didn't have reduced teeth at the shift points, but we did have bushingless chains from about the mid 70s (thanks SEDIS) and even shorter chainstays than modern bikes.

I'm going to give it a go. Hopefully it'll work just fine in testing and I can use it. Because bling. Such marginal. So gains.

I think it depends a lot on the chain line you are running at the time, the slackness of your chain (less links = less weight too, innit) and the quality of the road.

Most of the time I found it OK, but sometimes dropped, especially when changing to go up hill, which was always accompanied by much swearing and general loss of confidence for the rest of the race.

I made a slim guide which screwed on with the front changer mounting holes and worked a treat - never dropped a chain since.

Yeah, extreme edges of chainline are going to be the biggest issue - smashing it along an A road with a tailwind in the 11T for example.

Don't want the chain too tight though or there might be too much friction, no?

Quality of the road - this is Britain - they should be referred to as "goat tracks" not roads.

I'd prefer not to use a chain guide but I guess I'll see how it works in testing. What chainring and chain were you using? I've got 11spd DA so it might prove too much for a single ring. Not sure yet.

10 sp Ultegra

I've got 11spd DA so it might prove too much for a single ring. Not sure yet.

11-speed chain should run on any chainring designed for 9-speed or more

It was about the fact I'm running a wide block rather than some 80s 5-speed thing, ie. the chain angle might be greater and the chains flexier than old school kit.

Plenty of people run narrow/wide chainrings in cyclocross without clutched rear mechs or front mech guides - and there is a much greater likelyhood of dropped chains off road.

Also bigger chainrings might(?) help reduce the chances of dropping a chain due to bigger wrap....

Also 127mm vs 130mm wide isn't a big difference in angle (even when you consider that the older blocks c-c max to min tooth distance would be slightly smaller as well)

Really? They're not using chainguides or anything? In 'cross that seems mental. All the DH peeps seem to run chainguides.

Not sure - big ring front but small at the back might allow the chain to get whippy, especially bouncing over potholes and stuff. But I've no experience with 1x11 so this is all just guessing.

Also bigger chainrings might(?) help reduce the chances of dropping a chain due to bigger wrap....

More wrap doesn't matter because wrapped chain isn't taking part in the meshing process.

A larger diameter chainring does mean the distance between "tooth is starting to enter the gap between plates" and "roller fully in the cut between teeth" is greater, and the difference in tooth-plategap interaction depth between one tooth and the next is less, so if the chain angle is such that it's close to derailing, there are more teeth that might make sure it happens...

Narrow-wide means the a partially-meshed tooth in a wider plategap will still interact with the plate and reduce the chance of the next tooth missing the plates and derailing the chain.

I've not raced on it yet, but have done 75 miles in pretty mucky off road conditions on a single ring (from Absolute Black, made in Poland) on an 11 speed 105 rear mech and cassette. It's a bit noisy in the bottom two gears, but so far I've been very impressed with how well it works.

I have no chain guard or guide fitted.

Bodes well for me then.

drops chain on first use

Blatant self promotion:

I've just found out that online entries are open for my event this summer.

Islington CC Open 10 F20/10 25th July Probably the best/fastest/most awesome 10 within a stones-throw of London's famous London [Citation Needed].

Online Entry here: https://t.co/CBBMxTDLOz

Probably the best/fastest/most awesome 10 within a stones-throw of London's famous London

If it's not on the F11, it's not going to be the fastest.

Not so, I've arranged a tail wind in both directions.

The F11/10 is cheating anyway. Its basically all downhill.

17:53! Maybe I should throw in some fast course 10s this year to lower my pb.

Tell me more about this cheat course :) I've got the handbook. It doesn't seem to be used much.

Week after the 24hr... what could possibly go wrong.