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.