Tester's T3

Any reason why you're going to machine a Goldtec or is that just what you have already?

It's what I have from the old bike, but it would be choice between Goldtec and Gebhardt if I were buying one specifically; not much else easily available in 53x⅛"

Even in 144bcd? I thought they went right up to 56T in 1/8"

Even in 144bcd? I thought they went right up to 56T in 1/8"

Who they? Needs to be solid too, as conventional cut-away rings in big sizes have no metal where the Zipp mounting holes need to be drilled.

They would be the cat's parents.

Aero tape patch is lulz.

It's the little comedy touches that make it a tester project :-)

And I bet if we measured it, it would be 3:1...

please be 3:1...

It's really not far off, you know.

please be 3:1...

I don't have to be, CTT rules, not UCI. The wings on the Ventus are >6:1 at the centre.

It's what I have from the old bike, but it would be choice between Goldtec and Gebhardt if I were buying one specifically; not much else easily available in 53x⅛"

What are the goldtec rings like? They seem a solid, cheaper option for the track when compared the obvious imported stuff.

What are the goldtec rings like?

Like agricultural machinery; no frills, does the job, no attempt made to make them either light or pretty.

dura ace 56t,http://rover.ebay.com/roverimp/1/710-53481-19255-0/1?ff3=2&pub=5574889051&toolid=10001&campid=5336527178&customid=&item=260931755436&mpt=[CACHEBUSTER] may be of interest?

think it's 130, sorry

Even if I wanted a 56, and even if it was ⅛", it would be a shame to carve up one of those nice DA rings

Who they? Needs to be solid too, as conventional cut-away rings in big sizes have no metal where the Zipp mounting holes need to be drilled.

Aaah. Now I understand.
You're going to do something like this with the Vuma are'nt you?
http://swbkrn.blogspot.com/2010/06/track-bling-2.html

Pretty cool.

This thread has given me a headache. Too much detailing... you fucken' nerds.

I don't have to be, CTT rules, not UCI. The wings on the Ventus are >6:1 at the centre.

So this is a fixed gear TT bike, not a track bike?

I was tempted to do this with the Cervélo P2C I inherited from my brother after he snapped the derailleur hanger but have never gotten round to it. One day.

You're going to do something like this with the Vuma are'nt you?

ish, but my chainring will bolt straight to the crank without the adapter plate.

Too much detailing... you fucken' nerds.

I've hardly started...

So this is a fixed gear TT bike, not a track bike?

Yes, although I might have a look at some of our club track records before I put the brake on.

ish, but my chainring will bolt straight to the crank without the adapter plate.

How are you going to sort the chainline then?

A combination of moving one of the 1mm BB axle spacers from drive side to NDS, the already wide chainline of my Surly Fixxer equipped hubs, maybe putting a second 0.4mm shim under the sprocket and finally accepting that an imperfect chainline might be better than the extra frontal area associated with a spacer between spider and chainring. At the moment, without adding another sprocket shim, I have 45.77mm at the back and 46.45mm at the front, so just under 0.7mm offset. We can't be sure that the centre of the dropouts is that closely in line with the centre of the BB shell, so the only way to be sure that the chain is straight is to build it up and then stick the whole bike on a surface plate, chock it until the plane of the chainring is exactly parallel with the datum plane and then get busy with the dial guage and shims.

I see your point. 0.7mm of chainline imperfection surely shouldn't be a bigger sacrifice than having the ekstra frontal area and possible increase in turbulence around the crankset.

Some progress at last. The miller's work is done, but the turner is on holiday for another week. Fibrelyte is on the case for a couple of little carbon fibre bits. Here's a chain ring chopped down to fit the VumaChronos, and the Cervelo seat clamp modified for flush clamping bolts and mounting holes for a tail light bracket.

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Sorry to backtrack, but just to clarify.

Do you 'test' aero/TT gear as a job? or is this just for fun?