Here's my take after going for a search for the correct fork: get the rake intended for your machine. It is a MAJOR disservice to sell a frame without a fork, or worse yet, not say what the intended rake is. A fork with too little (or too much) rake can mean big, big trouble. I still have lower back pain from a wreck I suffered in June of last year. A big part of my bike's handling problems was the fact that I had a fork with too little rake.

What would I suggest? With as much weight as you will be putting on the front end of your bike with a Cobb fork (as it weighs as much, if not more than a Kestrel EMS fork. No offence, Cobb), I would get an MDT fork. It would weigh not much more than the Oval fork you are considering. The offset is made to order, and as many Giants as they sell, I am certain that they would have one made for your Giant in stock. It would not cost upwards of 500 pounds, and it would be plenty stiff. The profile is really small.

Reading between the lines here is it fair to say that the cobb's fork twin blade concept doesn't make purchase really significant over a standard aero fork ? He'd made some huge time gains when initially advertising the fork...

The Oval fork was designed to give the aero advantage over a standard fork in a profile recognised by the UCI as legal. If I remember correctly, it was not much (if at all) more aero than a Reynolds Ouzo Aero. I need to dig up the article from an old Velo News. I will say this with an invitation to Willet or anyone who has the fork article handy: correct me if I am wrong.

This being said, the most aero fork ever (according to good sources) was the old Schwinn Ashtabulah. It was very small, and it had great attributes for aerodynamics. The Hooker fork was probably pretty close to this, as I don't remember it being terribly large for a side-on profile. I am thinking that the MDT fork is as close as you'll get as the old Schwinn fork I mention.

I think any difference between the Oval and a Reynold Ouzer Pro was within the margin of error of the tests.

My question is - how does one know what rake is appropriate for a certain bike. If I swapped out my stock fork on my Trek road bike with an Oval or Ouzo Pro, would I be completely screwing up the handling?

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"If I swapped out my stock fork on my Trek road bike with an Oval or Ouzo Pro, would I be completely screwing up the handling? "

Depends on who you ask. Personally, I think that you subconsciously make the adjustment within the first few seconds on a bike. Anyone who tells you that they crashed because they ran a 40mm rake fork instead of a 43mm is making excuses for their own poor riding skills.

Anyone who tells you that they crashed because they ran a 40mm rake fork instead of a 43mm is making excuses for their own poor riding skills.


So, John- what are you trying to say?

You don't know what instances have occured for each case. I have over 200,000 miles under my belt, thank you very much. I was unable to make evasive manouvres on a) a very windy day where the road and shoulder of the road were NOT parallel, and b) a dog attack. I had run the "new" fork for over 1000 miles on this bike. My inexperience in mating correct rake forks is there culprit. In the early '90s, it was quite popular to put on Kestrel EMS forks onto bikes, and they had one rake. With the exceptions of frames that were within the range of the fork rake, people did have trouble with toe overlap, rubbing their fingers during a shift (from a spinning tyre), and the occasional horrid crash that was avoidable when these guys were running their stock fork. hmmm... Cat 1's and 2's were bad bike handlers? I think not...

Would have I avoided the crashes with a different rake fork? It is hard to tell. These were extreme cases, I admit. But, provided the engineer who designed the geometry knows what s/he are doing, there is an optimal fork rake for the frames in question. Otherwise, there wouldn't not be a need for multiple fork rakes, and the manufacturer would not even name their fork rake when making a frame or fork.

"So, John- what are you trying to say?"

I thought I was being clear. I am trying to say that blaming a crash on 3mm of fork rake is a joke.

On tri bikes, fork rake is generally 43mm for 72 degree head angles and 40mm for 73 degree head angles. This gives you a bit of extra stability versus traditional road bikes. Road bikes are almost universally 73 degree head angles with 43mm rakes. Switching between a 40mm and a 43mm rake will give you slightly different handling characteristics, but saying that it is dangerous and likely to cause a crash is hyperbole at best. I know Gerard advocates only a 43 mm fork for his bikes, but a look around any transition area or start ramp reveals numerous Cervelo's with 40mm forks. And I have yet to see one that has been crashed.

I am speaking from personal experience here - I've got road and tri bikes with fork rakes of 40mm and 43mm that I have mixed and matched. I've never had a handling problem due to the fork.

BTW - Toe overlap is generally not a concern in road bikes. The only time it comes into play is those 5 mph parking lot turns. There are tons of women and small men riding ~50cm road bikes with 700c wheels with tons of overlap. Like a different fork, it's just something you get used to and make adjustments for.

The Kestrel fork completely reinforces my point. You had thousands of guys using those forks on frames they were not designed for, yet there was no spike in the number of crashes. Nor did the fork ever garner a reputation as a poor handler.