Keiffith

Im having a custom bike built since what i want isnt on the market.

This is what im coining as a 'urban grinder'. Meant to ride at high speeds easily as well as take routes off limits to a standard road bike. 650b and 200mm travel dropper seat post.

What are your thoughts on the geometry, and the durability of an all road carbon fork jumping 2ft on 650b 47c tires?

General Geoff

Jumping 2 feet? On a rigid frame/carbon fork? Maybe on a fatbike...

bogydave

Keiffith

This is for commuting. The only compromise im making is a dropper post if i was going for a 'roady'.

I have had a 700c road with 28c tires for 6 months for commuting. I hate riding it long periods due to back pain. The bigger tires are to give me the supple life and reduce the shock at the saddle that's causing my discomfort. The roads in my area are rarely smooth.

Gconan

I love the awesome looking sloping top tube and the fantastic standover height! All bikes should come with such standover clearance !

rosefarts

Jumping 2 feet isn't a huge problem. Your tires should be fat enough. Landing it with drop bars is a whole new level though.

It seems that you want a gravel bike with a dropper post. Not the end of the earth Earth as far as custom goes.

Something to keep in mind though. It'll be a little slower than a road bike. Not nearly as nimble as a small framed mountain bike.

So high speed on the road and jumping off loafilo docks. Probably can't have both.

Lazyass

That's basically a 6550b gravel/bikepacking type bike like the Diamondback Haanjo 5C EXP. That drawing shows generous seat tube clearance with 650/47 tires and short 415mm chainstays. Not sure how realistic that is.

Marcus_Ti

You'll snap it. Like a twig. Carbon forks, brand name ones that are CPSC/ASTM approved, even heavily built CX alias "gravel" ones are rated for 6" drops. As a matter of standards this is called ASTM "Condition 2"...you need "Condition 3". Which you'll only find on MTB carbon forks, and as such--you'll need MTB geometry due to the much larger axle-crown.

If you're going to be doing parkour on a bike...you want a steel fork.

Keiffith

Its going to weigh less then my current road bike, so i would imagine that it will atleast not be slower than what im used to.

I did think it was a bit short to fit what i want. Ill aak him to verify.

I figured it would survive repeated falls above the 8-6in mark. Thank you for qouting the standards as that's way more helpful then saying just 'it will snap.'

tyrion

Whiskey #9 Mountain fork is rated "condition 3":

https://whiskyparts.co/forks/no9_mtn_15mm_fork

If you're getting a custom frame, having the ability to use mountain bike forks might make it more versatile.

Lazyass

A Cannondale Slate with lefty suspension fork would be a proper bike for the application. Ànd probably cost much less than a custom ti frame.

Marcus_Ti

Negative, ghostrider. The Lefty Oliver fork on the Slate is only rated to Condition 2 (6-inch drops or less): https://www.cannondale.com/~/media/F...133320_EN.ashx


Whereas their MTB Lefty forks are Condition 3 or 4, depending: https://www.cannondale.com/~/media/F...%20OMS_EN.ashx

tyrion

Oh! Titanium fork:

https://www.ticycles.com/store-all/f...ak-29-titanium

You can get that one at a custom length if you don't want MB geometry. $650

dsaul

I build my own frames and my current gravel bike is very similar to your design. 415 stays with a 47mm tire and 50/34 chainrings is going to be hard to do, especially in Ti because the stays are usually a larger diameter than steel. I have 420mm stays on mine with 60mm of BB drop and the clearances are close. I am using the Whisky No.9 15mm fork and have ridden some pretty rough terrain and drops with it. I don't think I've done any 2' drops yet, but I wouldn't be afraid to send it with this fork.

WizardOfBoz

Geometry looks like this Engin bike, which has the Whisky fork.

Keiffith

Thanks. I looked high and low for one to use and couldn't find one. Im thinking it will be an upgrade path.
Im pretty sure your right about the stays.
i have a similiar fork spec'd. Im thinking i can use it and if i encounter enough circumstances where jumping 2ft becomes a regular thing, ill upgrade to Ti

Thats close to the SingleBe killer II that I started with.

Lazyass

Compare a carbon road fork to it.

Marcus_Ti

Both will fail if faced with the 2ft drops the op wants to do. So neither is really an option.

Maelochs

It seems there are some bikes on the market which would almost work for the OP .... And if I were going off two-foot drops, I'd want the Ti fork ...

How often do you go off two-foot drops?

You do a style of riding i don't, it's clear. Are you looking for a bike with which you can sensibly, comfortably, efficiently commute and till do urban assault/MTB tricks? Do you really want to grind your Ti frame down curbs, walls, and stair rails?

Lazyass

The videos I've seen of Slates being jumped didn't have forks that failed. And if they do they aren't going to shatter into a thousand pieces.

mstateglfr 

its for commuting and you need to jump off 2' cliffs? On a tangent to your original post, we need pics of this commute!

its already been discussed what sort of fork you need. Time to change that geometry to accommodate an mtb fork.

dropper post is a unique request.

please post pics once you have it built! It'll be a very unique bike.

Keiffith

I am a full time commuter. If im leaving my apartment, im taking my bike. With the exception if the occasional bar visit.

I have seen opportunities where if my bike was up to it, i could take either a shorter, or atleast more fun route.

2ft is a conservative tollerance. Realistically i only need about a foot, but if i encounter a 2ft drop, id like the peice of mind the bike can handle it.

I looked at my options from both mtb and gravel. Nothing with rival 22 in Ti or steel fit the bill. So rather than throw money at a bike post purchase to make it what i want, id rather spend that amount on custom.

The Ti fork that i can order shorter seams wil fit the bill instead of the awkward drop bar with mtb fork look.

Lazyass

24 inches isn't much of a jump, especially on 47mm tires. Just be smart and land rear tire first.

Garfield Cat

Let's take a look at this Unicorn custom builder and what the builder has in mind:

Unicorn Cycles

Wildwood 

Very uninspiring site. Especially when the Gallery includes a couple of bikes in many settings and a huge number of stufted creatures some of which look like unicorns. Custom Ti for $1400??? Good luck.

I think they have more experience making stuffed animals than bicycles. Not a single word about who they are, what they have built in the past, where they are. Not my kind of custom bike builder. I advise not paying in advance.