Focus Paralane: Seat Post and Di2 Battery

The Focus Paralane comes with its own seat post, which is quite usual nowadays if you buy a frameset. For example, the Cervelo Aspero frameset that I bought also has a seat post included.

On this Focus Paralane, the seat post size is an uncommon 25.4 mm diameter, which is yet another quirk of this frameset. Most road bike frames use a seat post of diameter of 27.2 mm, or their own proprietary aero seat post.

From my experience, I would need a seat post with zero setback, but this frame only comes with an offset seatpost. It is very hard to find a good carbon seat post with a diameter of 25.4 mm, so I shall use this first.

Carbon seat post of diameter 25.4 mm, included with the Focus Paralane.

There is a big cutout for dampening bumps, which gives it a very unique look.

There is a pretty big setback, which I understand is necessary for the flexing and damping to work. However, geometry wise it is not ideal for me.

The saddle rail clamps are pretty solid, with a long clamping area that is friendly to carbon saddle rails. I like this clamp design, but not the setback seat post.

This carbon seat post is actually made by BBB, with a length of 340 mm.

If you look carefully, there is a groove on the inside of the seat post, for the internal circlip.

This is where the Di2 internal battery will go! This seat post is designed to accept a Di2 internal battery, if you choose to run a Di2 drivetrain.

Weighs 200 grams exactly. Pretty lightweight, I have no complains about this weight.

Internal diameter of the seat post is about 18.6 mm, which is designed to fit the Di2 internal battery.

These are the parts that usually come with the Di2 internal battery, but rarely used.

If you ever wondered what those two semi-circular plastic pieces are for, it is to wrap around the Di2 battery.

There are also a few spring washers and a circlip for fixing the Di2 battery into the seat post.

Normally, for seat posts of larger diameter, a rubber plug is used to fit the Di2 internal battery inside the seat post. These spring washers and semi-circular plastic pieces will never be used. Example shown is from the Fabike C3.

I found that on this Focus Paralane seat post, the Di2 battery can actually go in too far, if you are not careful. A properly designed seat post would control the depth of the hole exactly, so that the spring washers can be installed. However, in this case there is no depth control.

Tying some string between the Di2 battery and the Di2 wire, in case I need to fish out the Di2 battery.

In case the Di2 battery goes too far in, I can use the string to pull it out from the seat post. That's the theory anyway.

Also tying a loop of string around the Di2 wire, in case the Di2 wire drops inside the seat tube, I can also use the string to fish it out.

As for the circlip, I found a tool that is specially used to install or remove circlips.

The small pins at the end of the tool can be used to hold and compress the circlip, before installing them. Much better than using pliers.

With the Di2 internal battery installed, and the circlip inserted to stop the Di2 battery falling out. Nothing to stop it going further in though.

The two pieces of semi-circular plastic shown earlier wraps around the Di2 battery snugly. Surprisingly, it fits perfectly into the seat post! It is just tight enough to prevent the Di2 battery from sliding down, which hopefully means it will not go deeper inside as well.

Adding a Fizik seat post ring to minimize water from entering the seat tube.

A layer of clear plastic is used to cover the gap at the back of the seat tube, to prevent water getting into the seat tube.

With a big setback, I have to push the saddle all the way forward, to place the knee over the pedal spindle.

As shown from the picture above, I have to compensate for the seat post offset by pushing the saddle rails all the way forward. Even so, it is not enough to get my preferred saddle fore-aft position. The seat post setback is too much, which messes up my riding geometry.

The saddle position is about 10 to 15 mm too far back, which is not that much, but something I can feel. Until I can find a suitable 25.4 mm seat post, I will have to make do with this stock seat post for now. Once again, another quirk of this Focus Paralane frameset that I will have to live with.

The more I write about this bike, the more I wondered: Why did I accept so many drawbacks on this bike? 

Focus Paralane: Curana Fenders and RAT Thru Axles

The Focus Paralane is designed to be an endurance bike, with its tall stack for a less aggressive riding posture. It is one of the few road frames designed to have integrated mudguard mounts. In fact, this frame is so integrated that special mudguards are included, specially designed and made by Curana to match this frame!

Here is how the matching mudguards are supposed to look on the bike.

This picture shows the newer version of the rear mudguard, with two pairs of mudguard stays to support the mudguard.

For a sleek look, the mudguard is almost flat across the sides, without a deep curvature.

Textured wording and design makes the mudguard look really premium.

As seen above, those are marketing pictures that I found online. Unfortunately, I was not able to replicate these pictures, as explained below.

Mudguard with a combination of matte and gloss texture, looks really good.

At the rear seat stay area, the mudguard is pinched inwards, for clearance with the seat stays.

Measures about 39 mm across at the widest point. This should be wide enough for 28 mm wide tires.

It narrows to 35 mm at the pinched area.

This is the condition which I found the rear mudguard. It was bent and deformed, even before using it.

It is not possible to fix it properly, as the aluminium mudguard has already been deformed to this extent. 

As I had already planned to use my own SKS mudguards, the bent Curana mudguards was not a deal breaker for me. However, if I had planned to use the stock mudguards, I would be extremely annoyed as I can't use it, due to it being bent out of shape. Even if it is repaired, it will probably not have a smooth curve to match the tire.

At the other end of the rear mudguard, there is a cutout for clearance with the front derailleur.

The set of mudguards as I received it. Bad condition, luckily I didn't need to use it.

Mudguard stays with straight ends, to match this frame.

There are only two mudguard stays, as there is only 1 set for the front and 1 set for the rear. Normally, there are 2 sets for the rear, as shown by the pictures at the beginning of this post. Sadly, that is the improved version with 2 stays for the rear mudguard, not the older version that I have, with just 1 stay at the rear.

Based on research prior to getting this bike, I had already planned to use my own SKS mudguards instead of using the stock mudguards. Reasons are:

1) Rear mudguard only has 1 mudguard stay, which means that the top part of the mudguard is not supported well. Over bumpy roads, the top part of the mudguard will bounce and touch the tire. This is what I read from online reviews.

2) Rear mudguard has a cutout at the front derailleur area. It is necessary for clearance, but also means that this area will have water splashing through due to less coverage. Not ideal as it will spray water all over the chain ring area.

3) Front mudguard does not have enough coverage at the bottom, as there is no rubber flap. This will allow water to splash up onto the chain ring and also the rider's feet.

Nevertheless, there are some parts which I need from the mudguard set. These would be the brackets that hold the mudguard to the frame.

This is the plastic piece that holds the top part of the rear mudguard to the mount. The flashing on this resin part is very bad. I will not require this.

Unique bracket to hold the rear mudguard in between the seat stays.

There is no built in mudguard mount in between the seat stays, so that it has a clean look if mudguards are not used. However, if needed, this additional bracket will fit in between the seat stays.

These are the parts that are included with the stock mudguard set. Good to have a part list to check.

Just for fun, I weighed the stock mudguards that I will not be using. These are lightweight at just 377 grams.

I will be using a new set of SKS mudguards, so these stock Curana mudguards will not be needed. I will only require the chain stay bracket, and nothing else. Detailed info on the SKS mudguards will be shared in a later post.

Another component that came stock with the Focus Paralane are the unique RAT thru axles. In theory, they make wheel changes really fast, as only a quarter turn is needed to loosen or tighten the thru axle.

Both front and rear thru axles are 12 mm in diameter.

RAT stands for Rapid Axle Technology.

Instead of a M12 thread at the end, a T-shaped hook is there instead.

Basically, you slot the T-shaped end of the thru axle into the nut, and twist it 90 degrees to lock it in place. Then, the lever is closed to apply locking pressure.

However, due to frame and hub width tolerances, it is necessary to fine tune the axle length, so that when the lever is closed, sufficient closing pressure is created.

The adjustment nut under the lever can be adjusted by hand, which fine tunes the axle length. If the lever does not close tight enough, the nut should be adjusted to shorten the axle slightly.

Nominal front thru axle length

Nominal rear thru axle length

Note that thru axle lengths, not just RAT thru axles, are very dependent on the thickness of the frame or fork dropout. Taking the fork as an example; Even though the hub width is 100 mm, the fork leg width and nut thickness will affect the length of the thru axle required. This is why most frames come with thru axles included.

Front thru axle weighs 56 grams

Rear thru axle weighs 61 grams

The weight of both thru axles is this 117 grams, which is a bit lighter than the pair on the Cervelo Aspero, that weighs 129 grams.

The weight of the thru axles don't bother me. However, what bothered me was the design of the RAT thru axles. I identified three issues that I could not live with.

1) During insertion of the thru axle, it was difficult to determine which angle to push the thru axle in, so that the T-shaped end slots neatly into the nut on the other side.

2) Due to the thickness of the adjustment nut and the lever, the RAT thru axle sticks out a lot from the side.

3) The lever resting angle cannot be adjusted, which causes the lever to stick out at awkward angles.

Although the thru axle length can be adjusted, the lever angle cannot. It is determined by the slot angle on the nut. Since the slot angle on the nut is fixed, the lever angle is also fixed, unfortunately at weird angles. I saw that newer RAT thru axles allow the nut angle to be adjusted, which in turn enables the lever angle to be adjusted.

There are aftermarket thru axle designs which can be used to replace the stock RAT thru axle, but that is a story for another day. Once again, similarly to the mudguards, I will not be using the stock thru axle design. 

It may be curious to you, why did I get this Focus Paralane frame, if there are so many aspects that I didn't like (mudguards, thru axles, tall head tube, press fit BB, etc). The thing is, I didn't have other choices, if I wanted a lightweight carbon road bike frame with integrated mudguard mounts. There were a few other options, but the tire clearance became really small when mudguards are installed.

For example, the Specialized Diverge is a high end frame, but the S-Works version actually weighs about the same (995 grams) as this Focus Paralane (1005 grams). The lower grade versions weigh more and yet cost more as well.

Focus Paralane: Fork and Headset

Following up from the Focus Paralane frame details, here is the info for the corresponding carbon fork and unique expander design.

Focus Paralane carbon fork, in the matching Racing Green colour. Front brake hose enters from the top and exits at the side of the fork leg, same as most other forks.

Production code of the fork is manufactured into the fork itself.

Also uses the RAT thru axle design at the front. This design is patented by Focus, and is not widely used.

The "nut" for the thru axle is fixed to the fork by a bolt. Can be replaced if necessary.

Flat Mount brake caliper mount on the front fork. Good to see that the surface is flat instead of bring painted over.

Mounting for mudguard stays. The mudguard stay will stick into the hole as shown, and be fixed by the set screw as shown above.

Threaded insert at the back of the fork leg, also for mounting the mudguards.

As the stack of this frame is really high, I expect to set the stem at the lowest possible point on the steerer tube. This means that cutting the steerer tube will be necessary, as I do not want a tall stack of spacers above the stem.

Upon removing the included top cap, I noticed something special inside the steerer tube, which I have not seen before. Normally, for carbon steerer tubes, an expander will be placed inside to grip onto the internal walls of the steerer tube. However, this looks different.

Is this an expander? Looks different and works differently, as I could not loosen it to remove it.

This is what the manual that came with the Focus Paralane bike shows. Obviously what I have on the bike is different from what the manual states.

Time for Doctor Google to come to the rescue! I found some info in an obscure forum, talking about the expander used on the Focus Paralane. Apparently the mechanism inside is like a wedge, that is pulled upwards when the top cap is tightened. To loosen it, I need to screw in a long bolt, and tap on the bolt to loosen the wedge. This reminds me of the eccentric BB that I had on my Avanti Inc 3, where the wedge needs to be knocked loose first.

I inserted a long bolt, and knocked it to loosen the wedge.

The wedge will push against the knurled sleeve as shown below, when it is being pulled upwards by the top cap bolt.

Knurling on the outside of the sleeve, and a sloped inner surface (look carefully!) that interfaces with the wedge to act as an expander.

The top cap is also of a special design, with a spring below the top cap.

This design is really unique, but sadly it does not seem to work properly. First of all, the sleeve is so far below the stem clamping area, that it does not support the steerer tube internally. Then, it tends to slip when I tighten it. The spring design is puzzling as it resists the pre-loading of the headset bearings.

Stock expander and top cap design. Lightweight but does not work well. Perhaps I am using it wrongly?

Decided to switch to a conventional expander design.

Using the Cervelo top cap from my Cervelo Aspero, which I could not use because of the PRO Vibe stem.

New conventional expander plus top cap assembly weighs 62 grams, which is 20 grams more than the stock assembly. This includes a slim spacer and the stock tapered spacer.

Before cutting, the fork weighs 376 grams.

After cutting, it weighs a bit less at 370 grams. Almost as light as the Canyon Endurace CF SLX fork (361 grams).

I am happy with the weight of the Focus Paralane fork, as it is within the expected weight. The frame weighed a bit more than expected, but still acceptable.

In summary, the frameset (frame + fork) weighs 1375 grams, which is pretty OK. I couldn't find any lighter frameset with integrated mudguard mounts.

Frameset weight (with cut steerer tube)

Fabike C3: 1296 + 512 = 1808 grams

Cervelo Aspero: 1177 + 416 = 1593 grams

Focus Paralane: 1005 + 370 = 1375 grams

Canyon Endurace CF SLX: 807 + 361 = 1168 grams

As you can see, all are carbon frames, but the weight varies greatly. I am still amazed at how lightweight the Canyon Endurace frame is, given that it is not even claimed to be a climbing frame, but is instead an endurance frame.

On the other hand, the Fabike C3 weighs more like an aluminium frame, and I can save over 400 grams just by switching all the same components over to the Focus Paralane frame.

Stock headset of the Focus Paralane weighs 63 grams.

The first quirk that I have discovered on this Focus Paralane frame is the expander plug design, which is a bit more lightweight but does not work well. I'm sure there will be more as I continue building the bike.