1990 Raleigh Dyna Tech Cronos Titanium (56)

[Benandemu]

With the main components of the wheel sorted, I was eager to get the spokes organised. Using my cousin’s tool to find the ERD, and then with DT’s spoke calculator we soon established the optimum spoke lengths for a traditional cross 3 pattern.
I had planned on using either DT Revoltion or Sapim Laser spokes as they’re essentially the same as each other, and the best balance of weight and strength. As the Sapim are more widely available and significantly cheaper, it was an easy choice. They came in at 83p a spoke, and I’ll be using standard 12mm DT alloy nipples to help keep the weight down. I know what people say about alloy nipples, but providing you’re using quality nipples, and liberal amounts of copper grease when building them you’ll never see a problem. I’ve run them for years without issue. Plus, this bike isn’t going to see the rigours of our winter roads!



I also picked up some new rim decals for the other wheelset (the 32h ones) as the existing ones are just too scruffy. This 28’s are great though, and will clean up nicely.



The spokes arrived yesterday, and I found an hour this morning to lace up the front wheel. I’ve lost track of how many wheels I’ve built now, but I think this is the 9th pair, and exactly the same spec as what I used on my 1991 Merlin Titanium, which I incidentally tested downhill at just under 50mph last week. The thing was solid

 

[Benandemu]

I was too impatient, so I quickly laced the rear this evening

 

[Benandemu]

I’ll get the wheels tensioned up properly in the coming days, but for now they’re straight enough and sat in the corner waiting for rim strips.

My attention has turned to the brake calipers. I’ve several pairs of delta brakes I can use, and had initially sorted them out by year/type so they were matched to the right groupset and frame. Upon closer inspection, the ones I’d allocated for this build were far more tired looking than I’d remembered. They are the 3 pivot 4th generation calipers, so best matched carefully to the correct lever as they’re not as efficient as the last generation. One of the face plates is damaged beyond use, and the arms are scuffed badly on the front brake. I looked into replacement parts for these, but the money people want for spares is ridiculous. So much so, that it’s easier to purchase another set and butcher one up for parts.

So, I picked up an externally identical pair of rear calipers that have the 5th generation internals. From my experience, these are the best version, using 4 strategically curved arms, and 5 pivots, these apply more efficient pressure per lever input than the others, although they’re best paired with Powergrade or Ergopower levers for optimal performance.

The 5th generation calipers here have a few issues, but they’re cosmetically better, and will stop me more effectively. I do need to strip them though, and swap out some bits, namely the front mounting bolt, a brake shoe adjuster, and a c clip. Sounds easy in a sentence, but far more complicated than you think as the arms and internal mechanism need to be removed entirely I. Prefer to allow access to the mounting bolt. I will clean up and select the best components for the final calipers, and then have a spare set of rear calipers that could be used for future spares, or repaired to use as a set of brakes if I find the bits cheap enough.

I originally intended to butcher up a pair of Croce D’aune calipers I have, but almost every component is different. I never really bothered with the CDA group as it was a bit of a let down; not quite as good as C Record, and seemingly no better than Chorus.

These are the original calipers I had stored for use…




And these are the 5th gen rear calipers I bought as spares.



I’ll use this red brake as the basis for my new front brake. Starting to strip it down and clean each part, assessing and repairing along the way…




With all the dirt and grease removed I can start to see what needs what…



From the outside of the brake shoe you’d imagine there were two little grub screws as adjusters, but they’re not that straight forward ans you can see, so the missing one will need to be a genuine part replacement.



I stuck the cable adjusters in the end of my drill and ran them through several grades of sandpaper before polishing them up…



The rubber o-rings are available online at an inflated price, but I chose to measure my own and buy a lifetime supply for a few quid. The measurements are included in the photo for anyone wanting to know the specifics…

 

[Benandemu]

Actually, that job wasn’t as bad as I thought, and it went back together easily enough. Liberal amounts of grease was used in ensuring a smooth operation for years to come. The original factory grease around the tension springs was changed out too because it had hardened like plastic!



I do have some NOS spare rubber bellows, but I figured I’d try and salvage the ones I have for now, using bleach and a magic sponge. It worked pretty well, so I’ll repeat the process for the others.

Also. I’ve omitted the brake shoe guides as I never understood what use they were. I always thought they spoiled the lines of the brake, so I generally don’t run them. Plus, the original white ones haven’t faired the years very well, and they more often than not look dirty and yellowed.



And a picture of that all important front brake mounting bolt…