Bbloque Kaisei Steel - DM Rim (Complete)

[DHG01]

Build complete. Very pleased with the result and the ride.

[DHG01]

This bike will take some time – however, I think it will be very much worthwhile knowing the dedication Pablo from BBloque will put into it.
Not a bike that I need nor that should suit a certain purpose, just inspired on a gorgeous bike I have seen before – which many of you will be able to guess. And as I have said before, I do not like ugly bikes and find them unnecessary.

The bike will be steel and with direct mount rim brakes. Neither of which are particularly trendy these days.

Tubing will be based on the Kaisei Superlight tubeset. This tubeset is frequently used in Japan and you can read all about it a the Rene Hersey website (take it with a pinch of salt, as with other articles at RH – informative, interesting….but always best of best…).

We wanted to try something different to the more frequent tubes. Kaisei is frequently used for Keirin racing bikes. The superlight offers 2 options – short and long. We figured we could go down the route of long, which should result in lighter tubes – once cut, a larger proportion of the tubes are butted. These tubes are typically 0.7 – 0.4 mm wide. So that is quite similar to what you would find within Columbus Spirit or XCR and Reynolds 853 (if memory suits my right, Reynolds goes down to 0.35 mm).

One of the things that will make this bike special is the integration of the stem within the frame – spacers will not be available to adjust height and the stem is made by Pablo, swapping for a different height or length is not your typical Bike24 choice. So Pablo and I needed to get the geometry right. We worked based on the how the Standert Triebwerk fits me and left a bit of margin in terms of saddle-stem height. BTW, the Standert is a blast and alongside the Logic, the best off the shelve steel bikes I can think of.

Another special feature will be the direct mount brakes. I ve never had a bike with direct mount, and wanted to try it. For the rear wheel, they will be placed on the chainstays. Finding an aftermarket direct mount fork wasn’t particularly easy. We were almost tempted to not go direct mount in the front. I ended up searching road bikes with direct mount brakes. Quite a few of them were aero, which doesn’t really suit. Another challenge we could not work around was finding one that was 1 1/8 inch. I landed on a Trek Emonda SLR 8 fork. It is tapered, not ideal for a skinny tube bike and the head tube will have to be from a different provider.

In terms of the group set, it would have been cool to pair up Kaisei tubes with Shimano. But I wanted to try 12 speed and prefer mechanical shifting. Campy it is. By the way, excellent service from Ernesto from NNK (and thank you to the fellow weightweener that recommended him). I compromised for Record but with Bontrager Speed Stop Pro – that gets near SR weight. Ideally I would have liked to get SR cranks, but that wasn’t possible.

For the Wheelset, going on to 12 speed, I had to make a choice. Either Mavic CCU with Campy freehub body (thanks Campy for compatibility) or one of the others. In the end I am going for Schmolke TLO 45. Finding a freewheel hub for Campy was a pain. Also kind of annoys me not being able to use the Schmoke’s with the other 11 speed Shimano or Sram bikes. Anyway…the challenges life presents us with.

Saddle will be able Berk Dila – any bike is comfortable with a Dila.
Handlebar is an OG Evkin HB 010. Super compact, not heavy, and one that I wanted to try. Also, leaning on the cautious side, as once the frame is made, playing with stack and reach is not easy.

I typically use Shimano Pedals. I saw a great offer at RCZ on Mavic Zxellium SLR Ti pedals. At 160 grams, I thought I would give them a try.

In terms of seatpost, I want something in silver colour. I am leaning towards Tune Leichtes, but I need to figure out with final geo if I will have enough post sticking out. The Tune has an engraved upper part that cannot be inserted within the seat tube. Otherwise, Thomson MasterPiece or KCNC could be alternatives (recommendations are welcome).

Headset and bottle cages, tbd.

Integrating the stem within the frame will make it heavier. The Campy 12S 11-32 sprocket and the custom made stem will not help either. So I need to keep an eye on the rest of the components. I am aiming for 7.6-7.8. Recommendations are welcome, but not much manoeuvre at this stage.

The tubes finally arrived last week, but Pablo still has a long queue of XCRs to weld, so I don’t think he will be able to start until October.

[DHG01]

Edited with final weights and total.

[DHG01]

2 options for head tube. The idea is to work on and shape a tappered head tube. It should look nicer, and it's a way of integrated a wide, tappered fork into a skinny tubed frame.

I am still missing the headset and open to recommendations. Light, not too expensive. CK AER is one option; KCNC also have an interesting one.

[txomin]

Steel + carbon fiber ??

[DHG01]

Steel + carbon fiber ??

Sorry - didn't see your post. No, the tubes are all steel. The darker ones are not carbon fiber, it's jus the colour.

The fork will be carbon fiber (Trek Emonda more specifically).

[romanmoser]

maybe have a look at what english do
he machine his own cup so he's able to use a tapered fork without an oversized headtube

don't know why you couldn't be able to find someone to machine this

[DHG01]

maybe have a look at what english do
he machine his own cup so he's able to use a tapered fork without an oversized headtube

don't know why you couldn't be able to find someone to machine this

Thanks - that is the idea. I ll have a look - but the headset will be integrated and the idea is to have curved head tube. As you say, not rocket science; but it has to be done.

Also...English can do everything.

[romanmoser]

true he's a master on his own

[Prawn]

maybe have a look at what english do
he machine his own cup so he's able to use a tapered fork without an oversized headtube

don't know why you couldn't be able to find someone to machine this

Thanks - that is the idea. I ll have a look - but the headset will be integrated and the idea is to have curved head tube. As you say, not rocket science; but it has to be done.

Also...English can do everything.

Wittson's approach is worth a look. They butt the headtube internally and externally to accommodate a headset that is ZS44 at the top x IS47/33 at the bottom. It's quite neat. Although the Wittson is designed for a 1 1/4 to 1 1/8 tapper, the same idea could work for your 1.5 to 1 1/8 fork. Details here: https://wittson.com/handmade-titanium-f ... -suppresio

[DHG01]

I ve updated the weight list. Below 7kg, yet brake and shifting cable missing. That would lead to ~ 7.2/7.3 kg.
Very impressed with the weight of the pedals.

I still think I am missing something.

On the headtube front - makeing a one off head tube was becoming to complex/expensive/time consuming. In the end, we opted for a Paragon head tube. The Paragon headtube was small enough to match /fit with downtube and toptube; a standard tappered headtube wouldnt have looked that good. Luckily it was in stock. It will requrie external headset; we chose Extralite due to the very low stack.

Welding should start next week hopefully.

[DHG01]

The steel custom stem - it is heavy, but a great piece of work.
Bolts are obviously not final.
Main body is stainless steel. The other two parts, standard tubing.
Not sure if to varnish and keep the colour (will be mathign titanium seatpost) or to paint as the rest of the frame.

[stanvr]

That's a beautiful stem I think, paint might make it look more standard. I would leave it as is!

[DHG01]

Frame is now finished. A bit later than expected but very pleased.
I ll wait for the first rides, but I am quite impressed with Kaisei tubes. As the frame is built with the longer tube set, thinner area starts quite close to the joints.
Quite light also, partly due to sloping geometry - 1.6 kg with both derailleur hangers.

[DHG01]

And the paint job - difficult to showcase, but the colour is a two tone chameleon (red/blue); similar to the Klein I sometimes regret selling.