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Review: ProTi FFR Titanium Bolts Save Weight, Increase Strength Through Forging

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ProTi-Bolts

When trying to squeeze the very last bit of weight and performance out of a bike, some people turn to titanium bolts. Being just 56% of the density of steel, titanium can cut a lot of weight out the large amount of steel bolts that hold your bike together, yet Ti can be weaker when cut into bolts, giving safety concerns.

ProTi has a solution for that. By forging the bolt and not cutting it, the metal aligns itself with the end product better, creating a part that has all the weight savings of titanium, but retains the strength of a steel bolt. We took a first look at them in November, and recently picked up a kit to see how they stack up.

Ti bolts do not come cheap. ProTi’s FFR technology makes these some of the most expensive, but the forging makes them stronger so they can be used in more places. Take a look inside to see the cost vs weight savings, and decide for yourself if they can help make you faster…

Thomson-with-Ti-Bolts

At first glance, the ProTi bolts are well finished. We got our hands on a stem kit (6 bolts, M4x18mm) for $42, A brake caliper kit for two wheels (4 bolts, M6x16mm) for $32, and a set of disc rotor bolts for two wheels (12 bolts, M5x10mm) for $90. At this price, saving weight is just expected, but these things better look amazing too. Mounted to a Thomson stem, they do add a bit of visual beauty that is not present with the rough-finished stock steel bolts.

Stock-Thomson-Weight Thomson-w-TI-Bolts-weight

The $42 bolt kit installed on the Thomson 70mm X4 stem saved 10 grams. Most weight weenies try to shoot for $1 per gram of weight savings, so these are quite expensive. However, with their forging method that dramatically increases strength, these cannot just be simply compared to other CNC-machined Ti bolts.

ProTi-Bolt-Compared-to-Sram-Ti

Taking a close look at the bolts, you can see the finish quality present on the ProTi peices, as well as their strength. The two rotor bolts above were both installed once, and then removed. The titanium bolt on the left is what is included in a large manufacturer’s high-end brake, and is a standard machined titanium. I have found that many of these cut Ti bolts start to deform around the tool, even when just bringing them up to recommended torque. The ProTi bolt shows a better quality finish, as well as no deformation from an install and removal.

ProTi-Bolts-and-Packaging ProTi-Caliper-Bolts-with-Packaging

Knowing that these bolts cost a lot of money, and they need to be presented in a way that is worth that cost, the ProTi bolts come well packaged with a decal and instructions. While none of this matters once the bolts are installed, its nice to know that your expensive bolts are not coming in just some tape and bubble wrap.

ProTi-Caliper-Mounting-Bolts Shimano-Steel-Mounting-Bolts

Above, the ProTi caliper bolt kit ($32) is compared to a set of Shimano steel caliper fixing bolts. A savings of 17 grams is not too bad, and it shows that the larger bolts on the bike have a lot bigger return on investment for weight savings with titanium.

ProTi-Rotor-Bolts Shimano-Steel-Rotor-Bolts

When looking at brake rotor bolts, there is a savings of just 5 grams per wheel. This means that at the rotor, the $90 kit for both wheels will save you 10 grams, or about 3 times the cost for the same savings as the caliper bolts. Once you get down to this level of weight savings, you really need to decide how important each gram is to your ride.

Titanium also has other properties besides a low weight that may be of interest to some riders. Ti does not corrode, and if you ride in salty environments, they may help keep your components from becoming permanently fused by ferrous oxide. The ProTi bolts are also available in standard Ti color, gold and blue. If you want to add a spice of color, these can be used in areas where anodized aluminum bolts are not strong enough.

ProTi-Stem-Bolts Thomson-Steel-Stem-Bolts

The stem kit saves 9-10 (it was 10 when measured installed on the stem) grams for $42. The stem kit is where I begin to question the value of titanium bolt upgrades. Stems go through a very robust testing regiment to pass international standards, and the bolts can play a large part of the overall integrity of the stem. It is not just about the bolts being strong enough, but about being an entire system with the stem. Too much stiffness in the bolt could transfer stresses in ways not seen before, leading to a failure, or too little strength in the bolt could cause a direct failure. Even though the ProTi bolts are probably strong enough themselves, I’m not the kind of person that is too keen on risking another broken collarbone to save 9 grams.

The idea of replacing bolts with Ti to save weight has been argued for decades on bike forums across the internet. A definitive agreement will never be reached amongst riders whether geeking out the last gram of the ride, or a pre-race visit to the bathroom is going to provide a greater benefit. Obviously, these bolts are not for everyone, especially if you are on the “drop a deuce and ride” side of the argument, but if you love nerding out about the weight of your ride, ProTi FFR bolts are probably the best quality titanium out there.

www.proti-bicycles.com

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J Train
J Train
9 years ago

Hilarious.

John
John
9 years ago

Having been in the bolt engineering business for many years, this article leaves out the most important design criteria for bolts: the threads and torx tolerances The reason for the deformation in the torx (or if hex broach) is mostly due to tolerances in the torx profile and whether the head was forged or machined. The more play in the torx wrench to torx profile in the bolt head the greater the chance of deformation. Forging is great for being able to orient the the metal’s grain alignment the way you would want and can result in a slightly stronger part. Forging can help to improve fatigue strength as well due to better surface finish when compared to an as machined part, but the strength of the torx is a one-time stress and isn’t subject to fatigue loading (cyclic stress reversals) and this is why the tolerance of the torx profile in the head is the single biggest factor as to why the other bolt head shown in the photo was probably deformed (I’m assuming the bolts were made of Ti-6Al-4V or grade 5 Titanium with similar heat treatment).

The threads are also a very important element in the bolt’s performance since their forming can have a huge effect on strength. The type of thread, i.e. UNF or DIN specification can be used to design a much better part by using larger root radii to vastly improve fatigue strength. Also the radius under the head will also greatly effect the strength of the part. Too little of a radius and the head can be easily popped off.

ah
ah
9 years ago

The vast majority of steel fasteners are already forged, so you are just “losing less” strength rather than maintaining parity.

Also the idea that titanium doesn’t corrode is laughable. On it’s own, perhaps, but bolted into other metals like steel and aluminium you create a significant galvanic potential that is VERY likely to lead to electrogalvanic corrosion and the bolts seizing in place if they haven’t been generously coated in anti-seize…

rob c
rob c
9 years ago

I made the mistake of installing some forged titanium bolts from moto supplier pro-bolt, into my Thomson 4x 50mm stem on my slope style bike. Used a torque wrench during the installation.

I went dirt jumping for a day on a big set of trails, 31.8mm bars felt ‘flexible’ and horrible creaking from front end. Went home, installed the original steel bolts, no issues ever again.

Noticed most stems supplied with titanium bolts as stock have a different thread length, bolt diameter or even clamp design. Guess its swapping ‘like for like’ bolts where more flexible and weaker titanium bolts cause trouble?

bugstomper
bugstomper
6 years ago
Reply to  rob c

Titanium has more flex and rebound than steel.

Antipodean_G
9 years ago

There are some smart people around here…. @John

@ah, spot on with the corrosion issue. Ti when used with other metals can be a total nightmare.

Chris
Chris
9 years ago

@ Rob C. Interesting. Will have to pay attention the next time I’m on the bike with the ti stem bolts.

Robert W
Robert W
9 years ago

Steel is real. Ti is flexy. No way I’m anchoring my brakes with Ti.

Fraser Cunningham
Fraser Cunningham
9 years ago

Strong(er) bolts are not needed with Thomson stems – it’s the faceplate that will break! It’s a relatively heavy stem that’s not very strong, ironically!

anonymous
anonymous
9 years ago

Ritchey WCS C260 stem…same 70mm comes at 96g with original bolts, with some M4 Proti could drop down to -90g. Better face plate as well.

thesteve4761
thesteve4761
9 years ago

@anonymous

-90g? impressive.

Keep in mind there is a reason you can find C260 stems on closeout regularly. They are a pain!

Jmack
Jmack
8 years ago

I run titanium fasteners on both my boys BMX race bikes. The main reason is they resist rusting and discoloration. Mainly where the Allen wrench fits. It does save a small amount of weight, but pretty small overall. Titanium spokes and bottom brackets do make a difference though. I have had good luck ordering directly from China. I have had some stem bolts for 5-6 years. I just move them up to new parts as I get them. These bikes take a beating and I have never had a failure.

me
me
8 years ago
Reply to  Jmack

Yes I agree with you. A lot of people…I believe the vast majority overlook the bolts on a bike, its an important component…its keeping the bike together anyhow! if we also stop to think about ‘mechanical problem’…I’d say 99% of the times…there is a bolt involved…either corroded, stripped hear, broken…and even worst, parts of the bike damaged because of a bolt failure. I lamest thing I see is $10k plus bikes coming out of a bike shop with…..steel and poor quality bolts, such a trap!

Now looking at these, an enhanced quality of Ti bolts…hell yeah I want them…I value my bike.

sad
sad
8 years ago
Reply to  me

10k bikes tend to come with stock top end sram/shimano/etc stuff which are pretty much all titanium hardware or high end steel though.. unless you mean the bike shop swap em 🙁

Dennies
8 years ago
Reply to  sad

I’ve seen some less expensive bike being fully Ti, while some more expensive not even having 1 Ti bolt. I thinks it’s a matter of personal choice. Both metals have their unique advantages

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