Rigid carbon MTB forks - so light can they be safe....??

[mattr]

https://www.youtube.com/watch?v=tVPgV1MHpLk
Watch number 17........ the whole bike probably only weighs 7 or 8 kilos, frame ~1kilo, forks ~400 grams.......

And riding like that *isn't* so unusual

 

[LikeClockwork]

Re:

Bloody 'ell...... :shock:

 

[Osella]

Yeah, same kind of 'technique' for fitting crown races The Hope split races don't fit FSA Orbit MX's unfortunately (my go-to headset an almost anything as it happens) but the Dremel idea is spot-on and works too! Just remember to chamfer the edges a little to stop it snagging the lower cup outer seal if it's still present..

 

[catf]

Re:

i was tempted by a pair of those merida ones, what do they weigh?

i use pace rc31 on a couple of bikes and im 100% confident in them, but obviously they have the alloy crown and mag dropouts. they weight around 650g cut, or 600 for the c-type. a while back when those trigon ones started becoming available they were about 550g, so i didnt feel like risking it for the sake of 50g. even tho ppl say they were the same as the ritchey wcs version, you have to wonder if theyve been quality controlled.

now the chinese guys are selling forks that weigh around 450g, which is a bit more tempting, and my weenie project is at the stage where i cant really save that sort of weight elsewhere. i really wanna feel like you can trust these forks but i had a complete fork failure on a steep downhill when i was younger and as it cost me a couple of teeth, proper face plant.

i guess the thing is you get carbon road forks weighting like 350g which are good enough for the cobbles and the cx ones arnt much heavier. i doubt i will give them any more abuse than that. probably worth a risk right? just no downhill :s

 

[mattr]

I'd have more confidence in a monocoque fork rather than an early/retro pace. We had a good number of snapped ones through the workshop. Mostly gone at the crown where it had been over tightened.

Most of then had come through or been serviced by a very large pace dealer in West Yorkshire. Customers were always blamed......... Probably why they ended up at our place

 

[Wold Ranger]

Re:

Modern road and Cyclo-cross (CX) forks come a lot lighter these days and probably take far more hammer without a problem.
You carry much more of your weight on a drop bar bike on the front and don't have the cushion of a big fat tyre and the lower spoke tensions as on an Mtb.
I have a fork or two sub 325g with (one at 250g), Bear in mind 700c forks are also longer and carry bigger heavier wheels also, with the increased leverage they generate.
As said a Pace fork is far-far more likely to fail, as many in fact do at the crown.

 

[LikeClockwork]

Re:

Official weight for these is 750gms according to the ads, but Osella is saying his are 760gms (not much in it TBH!)

Mine weigh 830gms with the FSA Orbit headset bits on, and the listed weight for the headset is 96gms.... But it's difficult to get them to stay on my digi scales properly!

 

[Osella]

Orbit MXs weigh between 96 and 100g (weighed) for every one I've had (6 so far*).
My Merida forks - having just re-checked the weight, are 716g with a steerer cut to 210mm. So 750 is the weight with uncut steerer but they are pretty light and just awesome forks..

Best weigh to weigh forks I found is get a bowl or something, put bowl on scales, tare the weight and then put the forks on. Weigh them brake mounts up, then down, then steerer left/right and corroberate the weight you first got. It should be the same of course, but perhaps fluctuates by 1-2g Any more than that & you're doing it wrong!

*Yes, I am a bit of a weight weenie, I record the weights of everything as I get parts ordinarily - but then I know how much the finished bike should weigh and can select components accordingly in a build for weight vs strength/durability etc. Excel is my friend..

 

[LikeClockwork]

Re:

I feel so much better now....

A few months back I bought some digital scales specifically for weighing bike parts and a mate said she thought it was about time I sought help. I'm also very slightly OCD... :facepalm:

Steerer on mine is 210mm, so I'll recheck the weight later using the bowl method. But first I must put all my socks into matching pairs and align all of my books with the edge of the book shelf....

 

[kipperthedog]

Re:

I wouldn't be worried about OCD.

CDO though that's a different matter!!!!

Much more severe....like OCD....but alphabetically correct!