Lab test: Drop bar stiffness

By: kiritozhang　　Translator: alanyu

I have promised a lab test on the drop bar since the publishing of the test on the integrated bars last year. Let’s come straight to our product list. This test focused on the round drop bar (non-aero drop bar).

1. FSA K-Force SL compact

You can’t miss FSA when talking about the cockpit. Vision Metron 5D is the champion of our lab test on the integrated bars, while K-Force series is also reputed for its high stiffness. FSA updated K-Force light to K-Force SL these years. What’s new?

There is no much change on the main part, but the external routing (groove structure) has been replaced by the internal routing, and the weight is dropped slightly. The labelled width is still center to center (c-c) at the drops. The c-c at the hoods is 400mm of a 420mm size bar, which means the narrowest bar you can choose is a 380mm c-c at the hoods.

The shape is the classic compact shape of FSA, which they use from their entry-level to high end level, reach 80mm and drop 125mm, a small drop at the hood.

K-Force SL has a large hole at the center for fully internal routing (ACR system), which is rare in the market currently. The weight is now 182g while the old K-Force light is 190g.

2. FSA SL-K compact

The sub-top SL-K is also updated to the internal routing. However, mine is the old version with external routing. The MSRP of SL-K is 1769 CNY (~255 USD) while that of K-Force is 2570 CNY (~370 USD).

The old version has a groove for external routing underneath and the bar top is flattened. SL-K series has the same claimed width measurement as K-Force series, which is measured at the drops c-c. The old version has 380mm which means it is 360mm at the hoods c-c, while the new version has 360mm width which is 340mm at the hoods. It is really good news for teenagers and women.

The same classic shape of FSA. The difference is SLK has a flattened part at the drop, which is claimed to have a better ergonomics.

However, there is a significant weight difference between K-Force and the old SL-K. My scale shows 236g. The new internal version is claimed to be 196g of a 420mm bar.

3. 3T Superergo Team

The big cockpit brand 3T must join in the game. 3T doesn’t release any integrated bar, so we didn’t have them on our list of the lab test last time. Superergo is the successor of Ergonova, which improves several bugs of the old one. However, there are not many Superergos in China, as too many smuggled Ergonovas are still in the market.

The bar top is still flattened, but the routing hole has been moved from the bottom to the inside of the hood part, which certainly improves the smoothness of the cable.

The shape is also changed slightly. The drop around the hood is slightly decreased, drop is also decreased to 119mm while reach keeps 77mm.

The ramping angle of the bend doesn’t change. The labelled width has changed to c-c hoods while the old one is c-c drops. The smallest sizes of Superergo and Ergonova are both 38cm, which means you can choose 36cm c-c hoods only for Ergonova.

The weight of 400mm is 197.6g, rounding to 198g. You can further choose LTD version, if you want a lighter bar with the same shape.

4&5. 3T Ergonova LTD & Team OEM

The classic 3T Ergonova has been discounted but you can still buy it in China.

You can compare this picture with the Superergo. The shape is similar but the bend around the hood is slimer.

The classic shape of 3T is copied by a lot of OEM factories. The drop around the hood is a bit more than new Superergo. Some riders align the hood part horizontally, which makes the drop part too short. In our test both LTD version and Team OEM version are labelled 420mm, which are 400mm c-c hoods and 420mm c-c drops.

This is the weight of Ergonova Team OEM version (224g), which actually I didn’t know it is the OEM version. My friend told me that the weight is too heavy for the stealth paint version and it maybe fake. However, after I checked with the 3T dealer, it was proved to be genuine but the OEM version. There is also “OEM version” labelled at the stem locking aera and it is ~20g heavier than the retailed version. It’s a pity that I’m so poor that I picked up used bargains to do this test. (Translator’s note: NO! The author is lying here. He is super rich, like batman!!!)

6. PRO Vibe Carbon

PRO released SL version for their carbon bar two years ago. Now there are three different round carbon drop bar levels: Vibe SL, Vibe Carbon and PLT Carbon. The design of the old Vibe Carbon has been decentralized to the new PLT.

The old Vibe Carbon is disguised internal routing while the new version is updated to true external routing. The bar top is fully 31.8mm without reduction, aiming at the best stiffness. There is a small hole at the stem locking aera, but it is only for di2 cables routing.

Pro Vibe Carbon and SL shares the same design, a compact shape with reach 80mm and drop 130mm. The width is the same at the hoods and the drops. The labelled width is measured at c-c hoods. However, only Vibe SL has 38cm version while Vibe Carbon starts from 40cm.

Vibe Carbon weighs 215.5g. It is on the heavy side for a round top-end bar, before the release of the SL version. However, it is designed for the stiffness.

7. Enve compact

Enve is an upstart during the decade, and it has quickly sponsored several teams in the big tour, resulting in a good market. In China riders usually choose SES aero drop bar instead of compact if they want an Enve bar, as their prices are similar, around 2500 CNY (~360 USD) on Taobao.

Different with SES’ big flare, the design of compact is simple and traditional. However, the labelled width of SES is measured at the drops while that of compact is at the hoods, which is confusing.

The 400mm compact measures 400mm c-c at the hoods and 420mm c-c at the drops. It also has the groove for external routing.

TBH, the penis-like bar end plug makes me feel wrong, which is “Enve style”. You need to cut it if you want to mount the di2 bar end controller.

The shape of Enve compact is no special, reach 79mm and drop 127mm. There is no drop around the hood and it has a long tail at the drop. You can choose from 38cm to 46cm. A lot of brands have eliminated the size over 44cm nowadays, so it seems a bit ambitious for this American brand.

The claimed weight of. 40cm is 216g, including two “penises”. The bar itself weighs 206g.

8. Deda Superleggera

Deda is an old brand from Italy. However, not much people in China choose Deda carbon bars now. Superleggera, as the flagship, is really rare in China. Though it is less than 2000 CNY (~285 USD) on Taobao, they all need to be pre-ordered.

Deda Superleggera is also disguised internal routing. There is a groove underneath, and a shield which can’t be dismounted to cover the cables. This routing method won’t influence the smoothness, but still add the work of mounting and dismounting.

Superleggera has the classic RHM shape, reach 75mm and drop 130mm. The labelled width of Deda is measured at outside to outside (o-o) at the drops. The smallest width of Superleggera is 42 cm, which is 40 cm c-c both at the hoods and at the drops (no flare).

The weight is rounding to 181g, at the lower side.

9. Schmolke Oversize Compact SL

A German brand who aims at light weight. There are so many high-end German brands and Schmolke is one of them. Moreover, Schmolke is the first brand who made the first full carbon drop bar. The flagship product is TLO series and mine is the sub-top product SL series, which is a bit over 2000 CNY (~290 USD) on Taobao.

It is not important for those non-fully-internal-routing bikes whether it is an internal routing bar or external routing one. The internal routing through the bar not only brings more work to the mechanic, but also makes the brake less smooth. Schmolke is also external routing and there is a groove for routing underneath.

The labelled width is traditional, which marks the width o-o. SL only has 42cm and 44cm. The 42cm bar in the tested measures the same at the hoods and drops, both are 400mm c-c.

However, Oversize is not oversized at all. The drop part is super short and it can hardly be mounted with the di2 bar end controller. Except the strange drop part, other part is normal. Reach is 83mm while drop is 133mm, and there is some drop around the hood.

Though SL series is sub-top, its weight outstands most products from other brands. It weighs 161.9g, rounding to 162g. The super short drop contributes to such a low weight.

10, Mcfk

Mcfk is another brand from Germany focusing on the light weight carbon products, which is famous in China. Their products are not super light as Schmolke since their point is on the balance of stiffness and weight, which is recognized by many people. Besides the handle bar, their stem and seatpost are also welcome. The price of this drop bar is around 3000 CNY (~430 USD) on Taobao.

Their official website is, a bit, eh…, a bit humble. They even don’t name this drop bar. My Mcfk bar is labelled 400mm, which is c-c at the hoods, and it is flared to around 430mm c-c at the drops. The bar is flattened underneath for external routing.

The reach and drop are 77mm and 130mm on their website. However, the bend is a bit special, and it back sweeps 5°, so a lot of people consider the effective reach is 60ish mm, which is not true. The claimed 77mm is effective reach. The narrowest option is 360mm, which follows the trend of narrow bar these days and it is really welcomed by Asians.

If you align the bar end in vertical direction, you can see the upper part of the bend is quite straight and horizontal and there is only a little drop at the hood, but there is only inclined tube at the drop. Some people may prefer a horizontal aera at the drop.

You can see the backswept clearly in this figure. My 3k finished 400mm bar weighs 179.6g, rounding to 180g. It is said that the new version shaves off a bit of gram.

Method

The test includes pulling upwards and pushing downwards on the single side, to simulate the situation of sprinting out of the saddle. The force on the drop is referred to ISO standard, applied at the 50mm before the bar end, while the force on the hoods is applied at the 26±0.5° position, referring to the place where the lever is mounted. Our machine cannot lock the drop bar itself, so we choose Specialized Venge Stem 100mm, which is very stiff, to mount the bar.

The data in this report is only responsible for the sample we tested, and it may be not highly accurate. We tested all the bars on the same machine, at the same angle and the same position. Since we only tested one for each model, there can be some individual deviation. It is also more complicated in the real riding, such as lateral load.

The machine is sponsored by a big tour brand, which is accurate itself.

Results

Stiffness to weight = (Overall stiffness/4) / Weight

There is no stiffness advantage after FSA reduced the weight of K-Force SL, but the stiffness to weight ratio is better than the products from some other brands. We can see that the stiffness to weight ratio is similar among the products of the big brands. Though the sub-top products are ~20g heavier, the overall stiffness is better. This is why the big pros are using Team instead of LTD version if they are sponsored by 3T.

A high stiffness to weight ratio usually requires a top-class stiffness or a super low weight, or both. PRO Vibe Carbon scores the best stiffness and stiffness to weight ratio in our test, while its weight is on the heavy side.

The shape can also influence the result. In the test those bars with a short reach usually have a better stiffness at the hood while those with a short drop tail have a better stiffness at the drop. The shape of Schmolke Oversize can be considered as cheating. The drop tail part is so short that when we locked the load 50mm before the bar end, there remained almost no drop part.

After the lab test on stiffness, we also conducted the destructive test. Except few products from some super light brand became totally cracked, most products from other brands at more or less on the same safety level. We removed destructive test in this report and the stiffness results on the failure product under the requirement of that brand dealer. The products still existing in this report all passed the standard destructive test and reached the safety standard, which can be used with confidence. (Translator’s Note: the product failed to pass the destructive test is of A brand from Europe.)