I've got a couple of Ti bikes. It seems odd to me that they are fitted with carbon forks.
Every now and then I have a look around for Ti forks, but there's not much available.
Surely if Ti is good enough to build a frame, then it's good enough to build forks.
So where are they?
Surely if Ti is good enough to build a frame, then it’s good enough to build forks.
I don't see how one follows on from the other but here, have a full set.
People have done them over the years but I seem to remember them being a bit shit.
Why do alloy or steel frames tend to be paired with carbon forks?
I think I emailed a manufacturer about this ages ago, they explained that titanium doesn't have the same natural damping as steel or carbon, so a suitably light Ti fork would also be super twangy, or something.
I have a set of titanium truss forks, very good better than the carbon on my other bike... Design plays some part in that's well
Oh - and I've an ancient 26" V only Morati Ti fork on an ancient Gary Fisher Paragon. You can see the fork blades flex when you apply the brake!!! Lovely forks.
As if by chance: (Just spent 10min trying to work out how to embed an Instagram post without success, the shame...)
Titanium is a touch flexy, which means a standard twin bladed fork can end up on the hefty side to make it strong enough. Which is where the truss or quad design comes in handy, although to be fair they're never going to be superlight either.
They can be lovely and comfy though, Hannah was a fan:
Andrew (Spanner Bike)
Cost, weight, looks.
Fatigue an issue on unicrowns also I think.
That Spanner is lovely 8)
I've got a couple of pairs, a 26" disc pair that I've used for CX/gravel riding and a super-wide expedition pair for my fat bike I'm not a heavy rider and they do flex quite visibly. I do like some of the truss fork designs but haven't been able to stretch to the Blacksheep / Oddity Cycles sized budget. Xi'an Titanium in China will make you a pair but they'll be quite agricultural
In a frame you want a bit of compliance in the ride, so controlled flex is good. In a fork you want stiffness and precision to give good tracking. Carbon can provide a significantly better stiffness for less weight than Ti can without having to rely on triangulation to provide stiffness.
Fatigue in Ti is not an issue for bikes. The number of cycles encountered on a bike is significantly less than for an Aircraft and it's used just fine for 25+ years in that application.
Also, the typical strength of ti is well over 800MPa at low cycle fatigue, this only drops to 300-350MPa at around 0.5-1m cycles. Most bike components shouldn't be anywhere near the 800MPa limit, nor 500000 cycles for most of use cases.
Yep - cost and weight for Titanium and weight for Steel. Carbon is such a good material for a fork that it is silly not to use it really. The fork I have on my current bike is just over 300 grams yet is very stiff, track perfectly etc,. The steerer of a steel fork probably weighs more than my whole fork.
I had a set of Ti forks on a mid/late 90's Saracen Kili Ultra Ti frame. They were straight-blade, insanely light, looked cool and were visibly flexy.
It took a while to learn how to ride them to full effect; they would tuck under fractionally under braking and twang out of roots but they did give a good ride.
At the time it was one of very few bikes left that didn't come with suspension as standard (Saracen did a suspension option). The whole Kili range was so cool.
Kona did a straight blade titanium version of their venerable P2 fork. If you can ever find a set on eBay, they go for an absolute fortune.
Someone at Mountain Mayhem (I always took the Kili as my spare bike) once offered me £400 for the forks there and then!
still love my Jones truss forks, stiff, not divey, extra bit of offset too, quick turning.
cynic-al
Cost, weight, looks.
If it's Ti, cost isn't really a factor. Carbon wins every time.
Weight - again not a factor, otherwise you'd have a carbon bike.
Looks - I hadn't considered this to be important. If stuff works, then it looks good to me, form follows function etc, but a valid point, fashion seems to rule the industry.
I suppose that there isn't much availability of tapered Ti tubes suitable for a traditional fork shape.
I'll keep looking though.
If it’s Ti, cost isn’t really a factor. Carbon wins every time.
Weight – again not a factor, otherwise you’d have a carbon bike.
Not factor's to you maybe but factors to majority of people which explains why so few Ti forks, supply and demand and all that.
There are usually some Ti forks on eBay (from Asia) that are around £200. I wanted some when I had a Ti frame mainly FOR the looks as I like forks to match frame
I've got a 953 steel fork and that weighs 750g, so I imagine other steels are going to be significantly more.
Stooge do lots of different ti forks, black sheep, oddity squid fork ( which has influenced the spanner bikes homage to oddity) torus do a nice ti fork for a good price as well via clee cycles.
I've had all sorts, blacksheep, torus Jones, stooge. The blacksheep unicrown were comfy but bloody scary in hard braking. Torus are good but a bit unforgiving, truss forks seem to work well but they are marmite on looks
Fatigue in Ti is not an issue for bikes. The number of cycles encountered on a bike is significantly less than for an Aircraft and it’s used just fine for 25+ years in that application.
In Aerospace the Ti is not welded.
Unfortunately superficial understanding such as the above appears to permeate into some manufacturers too, so many frames aren't adequately designed and get cracks all over the place. This plays an important role in developing a safe, lightweight fork. A truss design can help address this.
As an aside, the only places Ti is used are where there are high temperatures or where there are concentrated loads (or high fatigue loading) - landing gear, actuator support points etc. You won't see any Ti used for large components as Al allows a lighter structure (again, very rarely welded).
961gm ti fork,stem and bars.
Boat anchor - my fork (carbon), stem (alu) and bars (carbon) weigh 580 grams
My old DNA 26" titanium (early 90's) I built up with titanium forks (V brake). Ran that hard XC and I loved the bike. I can't say I ever felt the forks twangy or had an issue. Though I was lighter then. Still got the bike. It also has a Royce titanium bottom bracket, titanium seat post and bars!
Pretty sure there were/ I bought the J&L ones, you can still buy an ebay for £200. I had no issue with them, though the bike has sat in my spare room for the last 15 years, and I've be riding other bikes. I see they do 29'er ones now. The shorter 26" length might make them stiffer, don't know.
Fatigue in Ti is not an issue for bikes.
Yeah, ti never cracks on bikes.
If it’s Ti, cost isn’t really a factor. Carbon wins every time.
Weight – again not a factor, otherwise you’d have a carbon bike
People don't buy ti bikes for weight obviously, but for the ride or coolness. They won't want to spend a fortune on a ti fork that's ugly, heavy and probably flexy.
And yes sub 1kg for a ti set up doesn't seem light to me, especially for the price. Almost cool but basically pointless.
We made some nice short Ti forks (400 to 420mm I think?) way back when suspension corrected wasn't a thing (or I was ignoring it).
They worked OK - nice tough fork.
Forks are much longer now, and stiffness decreases with the cube of the length.
So a 400mm fork is 64000 flexies, but a 490mm fork is 117649 flexies. Nearly twice as much!
I fitted a Ti fork to my Swift and then didn't ride for a few months. Went out for a couple of rides and couldn't work out why I was so bad, I just had no confidence.
Put the steel fork back on and all was fine. Wouldn't touch a Ti (non-truss) fork for offroad again, the thing was lethally flexible.
cynic-al
Yeah, ti never cracks on bikes
Ti bikes usually crack on the welds/seams, not on the tubes. That's a welding issue, not a material issue.
That's why so little (if any) welding happens in commercial Aerospace.
In Aerospace the Ti is not welded.
Unfortunately superficial understanding such as the above appears to permeate into some manufacturers too, so many frames aren’t adequately designed and get cracks all over the place.
Thanks PhilJunior for saying that. I was about to reply similar, but my knowledge isn’t as in-depth as yours as I was under impression there are in fact some instances (repairs?) where aerospace Ti is welded?
In any case - if it is in those instances - it’s still not welded by most likely under-skilled welders, and no Ti frames im aware undergo full X-ray weld checks.
umop3pisdn
Wouldn’t touch a Ti (non-truss) fork for offroad again, the thing was lethally flexible.
You mean it was a poor design.
The ability to flex is an advantage, it's simply a matter of designing properly for the material.
Take your example of the Swift fork (probably the nicest steel mtb fork I have owned) - if that had been done in a lighter gauge tubing, it would have been dire and poor design.
Similarly cracks around welds is poor QC.
High grade steels (eg 853) suffer the same when poorly trained metal melters are let loose without adequate supervision, which is why the likes of Reynolds will only sell to approved customers.
Raleigh UGLI Ti forks were bonded bitd - I thought they were cool.
Rex's- X-lite twin crowns looked cooler - but some cracked at the dropout ?
You won’t see any Ti used for large components as Al allows a lighter structure (again, very rarely welded).
The SR-71 Blackbird was 85% Titanium body, I guess at Al would get to hot at Mach 3.
Lots of Russian subs are 100% Titanium dual hulls, I guess they need the strength to weight ratio for buoyancy / depth rating.
and no Ti frames im aware undergo full X-ray weld checks.
IIRC the Sunn Exact Ti (made by Morati) complete bikes came with x-rays & the welders signature.
Lots of Russian subs are 100% Titanium dual hulls, I guess they need the strength to weight ratio for buoyancy / depth rating.
Exactly 7 were, all now retired. Mostly built as a political/propaganda statement. Extremely difficult and expensive to build and a nightmare in service as replacement of any large components or assemblies inside the boats required holes to be cut in the hulls - not easily done with titanium - and re-welded (also highly challenging on the required scale).