Need To Lighten Your Ride? Proti Fully Forged Titanium Bolts Are Light, But Also Stronger

Proti-Bolts-HeaderProti makes 6/4 Titanium bolts for motorcycles, using a technology where they are fully forged, including the threads. This relatively recent technology builds a bolt that has a much higher strength than a CNC cut bolt that is more typical of titanium bolts used in bicycles.

Andre Szucs saw what this was doing in the motorcycle world, and worked with Proti to become the representative of the bolts for the bicycle industry, and started www.proti-bicycles.com. There is a lot of science that explains why forging is better than cutting, check inside for the story…

_1377076826_0pxquj

Simply put, titanium has about 60% of the density of steel. This means for a direct replacement bolt, using titanium can save a few grams off each bolt on your bike. The downside is that typical CNC cut titanium bolts are not quite as strong, and are more sensitive to being broken if not torqued the correct amount.

Proti uses a forging process to create the entire bolt. Forging pushes metal into shape under great force, which causes the grain structure of the metal to align with the part itself. Think of metal like wood, except at a very microscopic level. If you apply pressure across the grain of wood, it will be strong, if you apply pressure along the grain, it will split pretty fast. And in CNC cutting, there is no way to predict where the grain structure of the metal will be. Forging, and hence aligning the grain of the metal with the bolt, makes a stronger part.

Proti-Bolts-strength

Proti, being from the motorcycle side, puts a lot of emphasis on material quality, strength and spec. The website information for each bolt is very comprehensive, something not typically seen in the bike industry. Every bolt is specified with all dimensions, weight and safety torque.

M5L08-OT01 $6.4Keep in mind, safety torque is what the bolt is rated for, and if your component specifies a lower torque, you should use that. If your component specifies a higher torque, you probably should not use titanium bolts on that part. This is in stark contrast to the typical bicycle industry lack of information.

This quality comes at a price. A commonly used M6x16 bolt costs $9.13, but weighs 2.9g. Far exceeding the theoretical threshold of $1 per 1g savings talked about in bike forums, there are many lesser expensive ways to save weight on your bike. High quality and good manufacturing processes come at a price, so they may be worth it to you. Or, gold bolts are just too awesome not to have.

Caliper-Bolts-2T

www.proti-bicycles.com

 

Subscribe
Notify of
guest

This site uses Akismet to reduce spam. Learn how your comment data is processed.

15 Comments
Oldest
Newest Most Voted
Inline Feedbacks
View all comments
Mr. P
7 years ago

This is great to have weight weenie bolts that are quality and aren’t from a mystery source.

P

anonymous
anonymous
7 years ago

“there is no way to predict where the grain structure of the metal will be.”

That’s just wrong, and the pictures you posted show that. 99.999% of the time, the grain will be going lengthwise. When metal is turned into round, it is usually either hot extruded, and/or cold worked into that shape, which are forging processes. Machining things from a cast ingot is exceptionally rare.

Antipodean_G
7 years ago

Interesting. No Ti bolt to date used in motorsport that I have seen (especially smaller M5 varieties) is recommended for critical load bearing applications, ie. brake mounts. While I guess you can, it’s at your own risk.

mark
7 years ago

Very informative. Forging has always been a better way to make just about everything. Even parts that look like that are 100% machined on every surface started life as a forged blank. As far as bolts, those do look nice. Forging them (cold heading as its called in the bolt biz) does make the bolt stronger but it will still never be at the same level as a steel bolt. I use some Ti bolts in places that don’t see much load but never in a critical location. I never save weight at the expense of safety.

Pistolero
Pistolero
7 years ago

Aluminium bolts might be dangerous, but titanium bolts can be used and are used in any of the bolts with no isses. Loads and stress in bikes are not that big to break titanium, even cheap chinese ti bolts. Now, aluminium, those may break easily in some parts.

Kevin Hodgson
Kevin Hodgson
7 years ago

I use titanium bolts from pro bolt, xc racer and uberbike components. None of these companies use cut threads. Cut threads gall like crazy as well as all the other stated disadvantages. I would say cnc cut titanium bolts are actually very much in the minority. Maybe on some unusual bike specific types only. I also wouldn’t worry about bolts breaking. Almost no bolts on a bike see cyclic tensile loads. On most the bolt just applies a force to provide friction between the two surfaces. Exceptions are 2 bolt seatposts and to a much lesser extent stems. If the bolt can take the torque without the head snapping off then it’ll be fine. I’ve even used aluminium bolts on brake mounts without problems.

anonymous
anonymous
7 years ago

I have some of those, and they are awesome! The ‘transforming’ Blue tone is very unique, never seen anything like it.

Matt Holland
Matt Holland
7 years ago

Lovely photos and all but i want to see a direct comparison of the tensile strengths of these bolts and some 12.9 HTS bolts, and a fatigue study.

greg
greg
7 years ago

although cut threads are rare, i havent seen any ti bolts that forged the heads. all ive seen are machined, and about half had an abrupt root just begging to have the bolt head pop off. another unintended consequence of machined bolt heads is variance in tool key depth. especially with button head bolts, some companies will cut too deep into the head and leave a very thin ring of material between the head and shaft.
…so much innuendo…

Velociraptor
Velociraptor
7 years ago

> A commonly used M6x16 bolt costs $9.13, but weighs 2.9g.
> Far exceeding the theoretical threshold of $1 per 1g savings

How much does a steel bolt of the same size weigh?

Velociraptor
Velociraptor
7 years ago

You are telling us that a steel M6x16 bolt weighs at least 12g while the titanium version weighs 2.9g???

Math fail.

toni796
toni796
7 years ago

if they only make them in red
i would buy them now

rehsper
rehsper
7 years ago

Antipodean, perhaps not in motorsport but in aerospace, Ti fasteners abound.

groghunter
groghunter
7 years ago

I could honestly see buying those blue bolts just because they’re so cool looking, but $10 a bolt is too rich for me.

Brendan
Brendan
7 years ago

Velociraptor, a similar steel bolt will weight ~5g. The author is saying that spending $9 for that 2 gram savings exceeds the $1 per gram threshold.