Time Trial / Time Trialling / TT

What chainring are you using?

Chain derailment is mainly a lateral problem.

One of these stronglight TT chainrings... 110BCD/53t

They have all the shifting ramps etc so that certainly isn't helping. I bought them because I wanted to use my existing 110BCD cranks and I struggled to find any single ring 110BCD/53t chainrings... but that was probably a false economy.

Q rings? http://www.velotechservices.co.uk/shop/vclose2.asp?prd=200801&cat=259
(obviously you won't get thick thin in 53 though!)

"The biggest ring we do in 130BCD currently is 48T"

But they might be able to go bigger.

Sram 130BCD 54t Narrow Wide?

http://www.tweekscycles.com/Product.do?method=view&n=3515&g=837204&p=837207&d=124&c=4&l=2&utm_source=Google&utm_medium=Base&utm_campaign=Road%20Chainrings&gclid=CJ_z0Peww8wCFbQV0wod8D4JDQ

FWIW there'll be two AeroCoach rings in single/long tooth profile, not narrow wide but long tooth for single, a 54t 130bcd and 58t 130bcd. We may be offering other bcd options but it'll be custom order and extra £££.

55T is too small now I'm ~30mph for shorter events. 56 might be a nice compromise but 54 is too small.

My Fibrelyte rings are long tooth/ SS and drop too easily without FD installed. I'm curious about NW but more useful would be chain guide, because I trust them.

That's fair enough, hopefully we'll have something out soon to sort it.

Before Saturday? ;)

Maybe not :D

Ride fixed and NONE OF THESE THINGS ARE PROBLEMS

Chain derailment is mainly a lateral problem.

The chain has to move up, before it can move off (to the side).

Do chains on 135mm OLD bikes not drop off single chainrings?

It's not the OLD, but what you do with it.

When road bikes do move to 135mm OLD, I don't suppose they'll re-space eleven speed, so I'll never be proved wrong.

Or right.

:/

Ride fixed and NONE OF THESE THINGS ARE PROBLEMS

Oh snap!

You're right, of course.

Then you just have the issue of being in the wrong gear most of the time.

That and the fact I don't currently have a fixed TT machine and am unlikely to get one by Saturday and I think you'll agree, sticking with the Shiv and a FD is the most sensible option.

I quite like the idea of that singlespeed that whatshisface used in the Newbury 12. That way I can chill out a bit and coast down the hills. Makes it easier when I want to adjust myself or feed or whatever too.

The chain has to move up, before it can move off (to the side).

And it has to move sideways first to be lifted up by the chainring teeth

I was talking about "chainslap" though (on the subject of single-ringers losing their chain).

If it just moves up and down, it stays on the chainring. It only comes off when it moves sideways far enough for the top of the teeth to catch the side plates.

It moves left and right
It moves up and down
If it comes off, you'll certainly frown

I suppose it depends on which end of the cassette people are losing their chains.

I assumed the top (when the chain has most slack), so when you get a slap the inherent flexibility of 11 speed chains allows a lateral "shimmy" to develop, catching the side plates.

This is what happens to me and the chain unships outboard around the crank so I can't pedal.

Anyone recomend a 10 mile tt route I could try in London?

lee valley cc do tuesday 10 mile tts at the Stratford Velopark

https://leavalleycc.microcosm.app/events/1700/

or their open tt is tomorrow (though a little far from London)

https://leavalleycc.microcosm.app/events/1701/

What's the range of your cassette?