Any question answered...

Why did Shimano use Torx chainring bolts on the Ultegra 6601 SL? And why did they feel the need to tighten them up so bastard tight without grease?

Had to get a Torx adapter for my socket wrench to undo them

Also, what's the best thing to do about a chainring guard which rubs when you switch to 1/8" chain? Stop using it and use shorter chainring bolts, directly against the spider (it's a double, with a single ring on the inside), or some kind of spacer, washer or shim?

irrespective?

with the proviso that........

Any idea of weight?

I'm afraid not, mine are currently in the bike that lives at the velodrome or in the bike that lives at my parents'. They're not heavy though, and you can shed more weight by cutting them down, as they come 400mm long.

On a Dolan DF4, like this:

(different spec, same frame), do I want the rear wheel as close to the seat post as possible, or more of a gap like in the photo? Common sense says as close as possible, but I know from experience that common sense rarely applies to aerodynamics.

Book some tunnel time, share the results for the good of the group.
(more of a gap, my bet)

I think the answer is "it depends" (on frame, wheel and tyre combo) - wind tunnel or some kind of aero field testing is needed to determine the optimum

About 10mm should be enough to diminish the shear layer drag to a small value without wrecking the flow off the seat tube and onto the wheel too much. As 6pt says, you need tunnel time to find the optimum, but more than a usual tunnel you also need a way of measuring the rear wheel's resistance to rotation while it's in the tunnel, as you're aiming to offset an increase in translational drag with a reduction in rotational drag. On the other hand, if you're just playing on the track then I doubt that there's more than 5W to be found between any wheel position from slammed forwards to hanging off the back.

Cheers chaps. If there's no obviously right answer (and hence no obviously wrong answer) then I'll just put it wherever I think it looks best. I'll probably try to match the gap between the front wheel and the cut-out in the frame.

48x15 will get you around the 393mm chainstay wheel position mark [bb-center to WP] on a fairly new chainring, chain and cog, do the math from here compared to your frame chainstay/drivetrain setup.

Guys please help, my front wheel has a rattle that I can't locate, it's driving me mad, no loose spokes. Doesn't roll around the rim freely but when shaken.

Here's a link to the video on Instagram as my wifi is playing up

http://instagram.com/p/sc9wjqoejp/?modal=true

No, just ride more.

What's the topic called where people can post their story? not the weekend ride topic but one someone made about their ride to Santander from Portsmouth.

Won't the rear wheel's position depend on the gear you're running?

https://www.youtube.com/watch?v=XB7UHYVuOpQ

Anyone know what makes that weird sound? Sounds like it comes from my fork or head tube. It rides fine just makes that weird noise when you put the bike down.

To an extent, yes it will. Obviously an extra link in the chain will give ~12mm more clearance, but it may be that one less link results in negative clearance and one more link results in a huuuuge gap, which leaves only one choice. We'll see - my @mdcc_tester approved 1Z1 was delivered today, so I can see what clearance I end up with. Next question is whether to stick with 50x16 or gear up to 50x15 for this winter's track training.

Loose headset or loose cones in the front wheel would be my guess.

1Z1

Hope that's for training and not racing. Gear up.

Yep, I haven't raced on track yet. Just lots of training. Well, I call it training, anyway.

Why would a 1Z1 chain be unsuitable for racing though? Or should that have been a reference to my ratios of choice?

IR: I got a new campa record headset mounted in there and a new carbon fork (both done by my LBS, specialized in track and racing bikes). My front wheel has closed bearings and is totally fine.

1R8 is the Tester recommended racing chain, 1Z1 is for training (apparently).

danstuff, as long as you get the 1/8 it should be fine. I don't see any issue with racing on a track as long as you do correct maintenance. You probably need a different chain on the side though, if you wish to have a nice gearing on track. If you wish to ride on track with your bike, I would personally advise a 50t on front and play with the rear for the street. Then swap the cog with something a lot smaller when you ride on a velodrome. That will result in a chain that is a lot longer. If you have short track drops the chain might be too long for the velodrome. Also dirt is not something they like on the velodrome, especially if it's a wooden. A clean chain for track racing is advised. You can run a pink no-brand 1/8 chain for all I care. People will look at you funny but still. If you wish to participate in championships it's a different story. Expensive chain with less resistance and whatever.

Check the wheel again, tighten it up if at all loose, got those things on the inner tube valve stem? They could be rattling around.

Does the same with no wheel in there.

Ah, gotcha. Well, this is definitely training only. No racing is allowed at the Centre Mondiale de Cyclisme - it's a training venue only, for some inexplicable reason.