Lightcarbon: New LCR017-D (or Yishun R1058-D)

[Serge_K]

Since I'm a cyclist and not an aerospace engineer, I don’t have access to a wind tunnel to measure these things. What I can say is that my bike performs perfectly in all situations, even on descents at 80 km/h. I've never noticed any weird noises or whistles like the ones you get from roof racks on cars, so as far as I’m concerned, the square downtube isn’t a real issue at all.

The drag would have to be insane for you to be able to hear it.
A bus isn't aero. Therefore, that downtube can't be aero. Would you be faster on a kamm tail shaped down tube? almost certainly. Would you EVER see a bus shaped downtube on a TT bike? No. Do you see kamm tail shaped downtubes on TT bikes? Pretty much 100% of the time.

Now, does it matter?
If you like your bike, great.
From my perspective, most of my riding is done on the flat, so i do care if i can save 5w at 40kmh, because i often ride at 40kmh.
And from the perspective of people considering the frame, they should know that this feature can't possibly be fast. Whether it matters to them or not, is for them to decide.

My frame arrived today and all my worries about quality issues faded 
Frame is a top notch without any wringles, cheese and etc.

Lovely bike!

[ceres]

The drag would have to be insane for you to be able to hear it.
A bus isn't aero. Therefore, that downtube can't be aero. Would you be faster on a kamm tail shaped down tube? almost certainly. Would you EVER see a bus shaped downtube on a TT bike? No. Do you see kamm tail shaped downtubes on TT bikes? Pretty much 100% of the time.

Now, does it matter?
If you like your bike, great.
From my perspective, most of my riding is done on the flat, so i do care if i can save 5w at 40kmh, because i often ride at 40kmh.
And from the perspective of people considering the frame, they should know that this feature can't possibly be fast. Whether it matters to them or not, is for them to decide.
Lovely bike!

Easy, just don't buy It   

[rasch]

I'm a bit surprised no one else has reported this issue before. I’ve already contacted Lightcarbon, and they just said it’s normal, but I’ve never seen anything like this on other bikes.

Yessss. I have it too. It's super annoying. I had a puncture last ride and it took me forever to get the thru axle aligned with the wheel.

Is quite annoying

[edy]

My frame arrived today and all my worries about quality issues faded 
Frame is a top notch without any wringles, cheese and etc.

That black and tan tire combo is mint!

[Walter-sobchak]

Has anyone out in the real world been able to quantify whether or not the square downtube is actually causing significant drag? Meaning, does the riding dynamics on road feel draggy? Can you actually tell?

I spent a significant amount of time riding side by side with friends on flat terrain, and as someone who pays close attention to power data, I feel confident that this bike doesn't come with an aero penalty. Based on what I've read about aerodynamics, the downtube is positioned in the 'dirty air' created by the front wheel, so having a slightly less aerodynamic shape doesn’t significantly impact performance.

[ceres]

I spent a significant amount of time riding side by side with friends on flat terrain, and as someone who pays close attention to power data, I feel confident that this bike doesn't come with an aero penalty. Based on what I've read about aerodynamics, the downtube is positioned in the 'dirty air' created by the front wheel, so having a slightly less aerodynamic shape doesn’t significantly impact performance.

I would also add that the biggest impact on aerodynamics comes from the cyclist and their position on the bike. However, it's true that I was looking for a stiff and lightweight frame, easy to handle on climbs. That said, with this bike, I’ve improved many of my personal records, even on flat terrain.

[Da11as]

I own a 2018 BMC Roadmachine size 54 and a 2011 Kuota Karma. There is no comparison with the Kuota, whereas compared to the BMC, I can say that, in terms of ride quality, I haven't noticed any significant differences. In fact, I actually prefer the LCR017 because I built it to fit my measurements. The geometry has a slightly longer reach and a lower stack. Surprisingly, I feel more comfortable with the lower stack, which is about 3 cm lower. As for the reach, I compensated by shortening the stem.

The frame I received is of excellent quality, and the assembly went smoothly. The BB on the LCR017 is a T47-68 mm, which threads into the frame and is easy to handle, whereas the BB on the frame you're proposing is a press-fit type, which is a bit trickier to deal with.

I wouldn’t underestimate the issue with the rear hanger. If you do races and need to change wheels quickly, I think it's better to avoid the LC frame. Otherwise, the issue is almost negligible, though personally, it does bother me a bit.

Yeah, that is clear. I am more about the ride quality, given you have same (or very similar) wheel setup.

[Da11as]

The drag would have to be insane for you to be able to hear it.
A bus isn't aero. Therefore, that downtube can't be aero. Would you be faster on a kamm tail shaped down tube? almost certainly. Would you EVER see a bus shaped downtube on a TT bike? No. Do you see kamm tail shaped downtubes on TT bikes? Pretty much 100% of the time.

Now, does it matter?
If you like your bike, great.
From my perspective, most of my riding is done on the flat, so i do care if i can save 5w at 40kmh, because i often ride at 40kmh.
And from the perspective of people considering the frame, they should know that this feature can't possibly be fast. Whether it matters to them or not, is for them to decide.
Lovely bike!

Quite many modern allrounder bikes have square shaped downtubes, Giant or Bianchi, for instance. It's not much a deal from perfomance perspective. But it indeed hurts my eyes...

[dinorello]

Quite many modern allrounder bikes have square shaped downtubes, Giant or Bianchi, for instance. It's not much a deal from perfomance perspective. But it indeed hurts my eyes...

I figure that are squared down tube is an easy way to add stiffness without adding extra weight

[reckonair]

Hi Guys,


I'm looking for a pretty aggressive and stiff all-out race frameset, I'm looking at a LCR017-D or a Winspace T1550.

I love the idea of both these bikes and I've heard rave reviews about the aggressive geometry and stiffness of the T1550.

I'm more interested in hearing about the characteristics of the LCR as it's more attractive on the wallet, how does it ride? how stiff is it? Would it make a good all out race frame?

Thanks!

[ceres]

Hi Guys,


I'm looking for a pretty aggressive and stiff all-out race frameset, I'm looking at a LCR017-D or a Winspace T1550.

I love the idea of both these bikes and I've heard rave reviews about the aggressive geometry and stiffness of the T1550.

I'm more interested in hearing about the characteristics of the LCR as it's more attractive on the wallet, how does it ride? how stiff is it? Would it make a good all out race frame?

Thanks!

I'm not really qualified to answer since I've only owned three road bikes and have never raced, even though I've ridden around 50,000 km in the past six years. Compared to the 2018 BMC Roadmachine, the LCR017-D is definitely more responsive when sprinting and generally a bit stiffer. However, with its slightly slacker fork angle, it's easy to handle—it's not twitchy at all. The geometry is certainly aggressive.

I’m not sure if this helps, but that’s my experience with it!

[WhityWhite]

I've just replied to reckonair privately and don't want to withhold it from the thread.

I built the LC for rides and/or road races, I think it's in the same genre as an SL7 or SL8... All-rounder...

The landscape here is varied. I can ride flat, hilly and mountainous. It's perfect for that.

But in my opinion not necessarily suitable for criterium races ... Geometry somehow doesn't suit me.
I ride licensed races (circuit and criterium - so both 1-3 km “in a circle” ) For this I had built up the ICAN A40 (identical in construction to the Cinelli Pressure). It's stiff! and it really moves forward!

Due to my promotion I got a place in a racing team and we got Merida Scultura for the next season - meanwhile also an all-rounder... That's why I sold my LC with a heavy heart a month ago, as I didn't want to let it sit in the cellar for 1-2 years. We also get wearing parts replaced, so pragmatically it wouldn't have been clever to keep the LC.

For crit races and fast road races, I would definitely prefer the ICAN.
Outside of crit races, the LC.

Before I sold it, I took a few pictures for my souvenir album

[dinorello]

Did you ever feel like the boxy down tube slowed you down due to its bus like aerodynamics?

[WhityWhite]

definitely no

[edy]

I haven't see a moving LCR so far. Just photos of bikes standing still, so ...