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How much threading is on an E70 fork? (nm)(22 posts)

How much threading is on an E70 fork? (nm)Kristin
Aug 8, 2002 5:15 AM
Oops, and a question about rake tooKristin
Aug 8, 2002 5:33 AM
Just to make sure I understand so I get what I want out of this upgrade.

Rake = curve right? So more rake would be the same as more curve? And the more rake you have the smoother the ride?? Is that correct? Thanks
I don't want to be rude...TJeanloz
Aug 8, 2002 5:41 AM
But are you sure you know what you're getting yourself into?

There's no reason to upgrade for upgrade's sake. And no, rake is not = to curve. Curve is purely (or at least 90%) cosmetic. Rake should be held constant, as it is a design parameter of the frame designer. If you put a fork with a lot of rake on a bike not designed for it, it will not handle correctly.

And on the original question, you need to buy a threaded fork of the correct length for your headtube, most forks have about 2cm of threading. You can opt to get a longer one and then have a machine shop (or sucker of a bike shop) cut threads further down, but that gets expensive.
I sure doKristin
Aug 8, 2002 6:04 AM
And do you really think that a bike with any fork installed will handle improperly for a person averaging 16MPH? I'm guessing that I wouldn't even notice a difference. So far, I have not had anyone tell me I shouldn't change forks. As a matter of fact, a number of people have suggested that a CF fork is a good way to cut out road buzz. And I've never heard that I must keep exactly the same amount of rake. Why would no one have told me that if its true in every cace???

I appreciate your comments. The only thing I found rude was your assume that I'm upgrading for no good reason. I know exactly what I'm trying to change and why. Thank you for explaining rake to me.
Not quite.Spoke Wrench
Aug 8, 2002 6:01 AM
Imagine a line from the middle of your headtube to the ground. You want the your front tire to touch the ground a bit behind that. On a car, that's referred to as "caster." Caster is good because it tends to center the wheel when you aren't steering. Too little caster and the wheel sort of vibrates from side to side. You've seen that happen with grocery carts. Too much caster and the wheel sort of flops over and is slow handling.

The more your fork curves, the LESS caster you will have. I think that your best bet is to match as closely as possible the amount of rake that was on your bike originally.

Threaded forks generally have about an inch of threading. Adding a thread or two isn't too bad a job as long as the steer tube isn't chromed.
Thanks, reason I was asking about the E70Kristin
Aug 8, 2002 6:12 AM
Nashbar has the forks on sale, but starting at 160mm for $129. Thats a great price, but I need a threaded fork between 145-50mm. If Easton cuts 25-30mm of thread into the fork, then a 160mm could be cut to size. I not gonna mess around with adding threads. If I don't order the fork at Nashbar, then I'll just have the LBS choose something inexpensive for me from their catalog.

How come in all the conversations I've had, has no one ever mentioned that I should try to match the rake? In two specific cases I was told I should go with lots less rake? That's rather irksome.
It is of course up to you...TJeanloz
Aug 8, 2002 6:23 AM
The decision to 'upgrade' to a carbon fork is, of course, entirely yours. And since I have no idea what you're upgrading from, I'm in no position to say that it's a bad idea.

However.

On the rake issue, not many people understand bike design very well. Rake is one of those things that shouldn't be changed in an ideal world, and if it has to be changed (you're getting a new fork that doesn't come in the exact rake that you have), it is usually better to err on the lesser side.

On the threading issue, again, I don't have enough information to say for sure, but where did the 145-150mm measurement come from? I assume you measured your old fork? 2cm of threading is actually not all that much to work with, and lopping 10mm off of that leaves you in a place where you might need to add some threads on the bottom.

But back on the upgrading issue. Keep in mind that a decent steel or aluminum fork is often lighter, more shock absorbant, and better handling that a low-end carbon fork. Many people believe that all carbon is created equally, just as they believe that all ti is created equally; but a carbon fork is not necessarily better just because it is carbon.
InfoKristin
Aug 8, 2002 6:44 AM
I didn't outline the details because I already knew what I was looking for. But just so you don't think I'm a complete moron. My LBS, who is doing the install for me, measured the fork. I need a 145-50mm threaded fork.

Problem: Sore/tired neck/shoulders

Causes of Problem: Handle bar height too low, stem too long & too much road buzz (which makes for stressful longer rides).

Fix #1 (Handle bar height & reach): Install stem with longer quill and shorter reach.

Fix #2 (Road buzz): Either install different fork or a different wheelset. Upgrading the fork is cheaper. (Though I have never really checked to see how well my wheels dampen vibration. Perhaps I'll do that tonight.)

This is a picture of the bike I bought from CBike. The bike in this picture is the exact bike that I test rode. The frame & fork are full Columbus Alle. I believe its a combination of frame design and materials that makes this bike a bit too noisey for my tastes.
One at a timeHap
Aug 8, 2002 6:54 AM
My recommendation would be to change one thing at a time and I would change the stem first. Fit, fit, fit, and all that.

I don't know what tires your using but you might reduce some road buzz in that department also by increased dia., lower pressure, etc.. I happen to think the carbon forks are largely a fad although I'm sure that a lot of folks will disagree.

Hap's $.02
Infojtkirk15
Aug 8, 2002 7:25 AM
I just bought the Easton EC70 from Nashbar. I got them to match the price advertised in Performance's latest catalog of $99 and they did (call them). I opted to change my threaded setup to threadless. For less than $200 I got the EC70 fork, 3T Forgie stem and Cane Creek S-2 headset. Good luck with your project!
I got rid of my buzz...Matno
Aug 8, 2002 9:41 AM
I recently made a few changes to see what really helped. First, I switched from vinyl bar tap to cork. That helped a little, enough to be noticeable.

Then I built a new wheelset. It hardly made any difference. (But the new wheels were a lot lighter, which made my bike faster...)

Third, I tried a new stem that was longer (my original stem was too short) but totally stiff (Profile H2O). Didn't help, and was a bit too long.

Finally, I tried a stem that was just the right length but had poor reviews for being too flexy (Deda Murex - on sale at Nashbar now). Voila! Vibrations are gone, bike is perfect. Lovin' life! Didn't have to change my fork at all (it's a stock Columbus steel fork on an old Schwinn SuperSport). Granted, the Deda stem is torsionally quite flexy (which is only a problem if you're concerned about every ounce of power being transferred when you're racing). Straight up and down and side to side, it's actually quite stiff. Somehow, that torsion takes the sting out of the road. I've even stopped wearing gloves, it's that smooth. (And I was using thick gel padded gloves).
I can't say why other people say the things they do.Spoke Wrench
Aug 8, 2002 6:32 AM
If I had to guess, I'd say that they just think a straighter fork looks more "racey." What I think they are overlooking is that the straight forks go with more vertical head tubes. The whole thing gets even more complicated because many forks use straight legs that are angled at the crown to yield the same rake.

For the record, I have a short list of posters on this forum that I would trust to work on my own bikes. TJeanloz is on it. In fact, I think he'd be my first choice to order all of components to build a brand new bike. Then I'd want GrzMnky to assemble it and Doug to cut the fork. On my old retro-grouchy stuff, I'd have to have Chen2 do the work.
I think you're vastly overestimating how muchscottfree
Aug 8, 2002 8:07 AM
'improvement' you're going to get with a carbon fork vs. the nice Columbus steel. My best guess: If any, it will be almost undetectable (although the Placebo Effect will be invoked, I'm sure -- whenever we spend money, we want it to MEAN something). I've found steel forks to be lovely, and in most cases superior to cheap carbon.

I also think you're vastly overestimating how much 'road buzz' contributes to your pain. I'd say almost nothing. Buzz doesn't hurt, it annoys.

You're on the right track by raising and shortening your stem. I've seen a picture of your bike, and it looked almost unrideable for the average Joe (or Kristen) out there. I don't know if you're looking for advice or not, but MY advice would be: Do the stem, get some wider tires and run 'em at lower inflation, and see if that solves your problem. The fork would be the last place I'd look, if I ever looked there.

Remember, I'm 50 years old and I KNOW where to look for comfort!
Kristin!!!!!!mlester
Aug 8, 2002 10:44 AM
If you can get ahold of "Performance" it is closing out on E70's for $99.99.....save a little money.

-ml
More info...mlester
Aug 8, 2002 10:55 AM
www.performancebike.com has the E70 listed at $149.99 but the Performance Bicycle Catalog (Summer Clearance 2002) has the 2001 Easton E70 listed at $99.99

-ml
Those are all gone. It was threadless anyway--no good for me(nm)Kristin
Aug 8, 2002 11:24 AM
sorry for the bum scoop.......nmmlester
Aug 9, 2002 2:33 AM
RakeChen2
Aug 8, 2002 8:49 AM
The curvature of a fork is not necessarily indicative of the rake. A straight fork can have the same rake as a curved fork due to the angle in the crown area between the steerer tube and the fork. Trail effects handling. More trail will help the bike continue in a straight line. Less trail will help the bike turn more quickly.
Trail is a function of head tube angle and rake.
Increasing rake will decrease trail.
Decreasing rake will increase trail.
A steeper head tube angle results in less trail.
A slacker head tube angle results in more trail.
As a guess, if you have a 73 degree head tube angle you would probably be happy with a 40 or 43mm rake. If you have something close to a 74 degree head tube angle I'd say go with a 40mm rake. BUT, that's a guess based on what I've seen on other bikes.
I agree with taking it one step at a time. You may not need a new fork.
If you replace the fork I would think seriously about going threadless, that way you could accomplish the same results and have less weight on the bike.
~Al
some observations ...tarwheel
Aug 8, 2002 8:18 AM
I think the point TJ is trying to make is that changing the rake will change the way your bike handles. The manufacturer presumably matched the fork rake to the frame in order to achieve the best handling characteristics. Therefor, you should try to match the rake of the new fork to the old one. If you do change the rake, try to determine beforehand whether the new rake will make your frame handle quicker (or twitchier) or slower (more stable) -- and base your decision on that.

Another point, I don't think the extra 10 mm on the fork steer really matters. The bike shop can add 10 mm of spacers under the headset to make it fit. Since you are trying to raise your handlebar, the spacers will actually help you achieve that goal.

As TJ was pointing out, a carbon fork may not damp vibrations any better (and perhaps worse) than your existing steel fork. Carbon forks vary a lot in their stiffness, so try to find out whether this particular brand is better at dampening vibrations or not. Personally, I think a good steel fork is hard to beat in terms of comfort. Finally, you may be able to raise your handlebar enough without the new fork if it has enough extension and rise.
re: How much threading is on an E70 fork? (nm)bcm119
Aug 8, 2002 9:56 AM
For a custom description of how specific fork rakes will affect YOUR bike, try Bill Boston's website, he's very helpful-

http://www.billbostoncycles.com/accutrax.htm

As for carbon cutting roadbuzz, I am a believer. Carbon forks vary in their stiffness, but this is seperate from their "feel", which relates to how they absorb high frequency vibration. Carbon feels silky smooth, and if you like riding in part because you love high performance bikes, carbon is worth very penny. If you like riding to be outside and get exercise, and you just want a reliable machine to meet that end, carbon may not be worth it to you.
Thanks for the infoKristin
Aug 8, 2002 11:36 AM
Thanks for the info about forks. Everytime I turn around, I discover that bikes are 10 times more complicated than I had counted on. I may just hold off on installing a new fork. I had my mind made up to upgrade it for while, but some posts may be right, I might change the stem and then be perfectly comfortable. Just rotating the bars up so the hoods are higher has helped me an enourmous amount.

Here is the logic behind road buzz causing pain. As I ride and vibrations are transferred into my body, I tend to become tired and/or frustrated. As a result I tighten the muscles in my arms/neck/shoulders or grip the bars too much. This, in turn, adds tension to my muscles which eventually knot-up and get stiff. The tightening in my shoulders/neck is also exagerated because too much weight on my hands. I wonder how much the road buzz will bother once I raise the bars level with the saddle.
carbon vs steel forks..dotkaye
Aug 8, 2002 2:06 PM
I had a cheapish steel bike, went to a Trek aluminium with carbon fork (Icon), and also ride a Paramount with a unicrown steel fork. I can't say that I notice any improvement at all between the carbon and steel forks, if anything the Paramount's fork is a little more comfortable than the Trek. I found the Trek to be a rough ride, but 23mm tires instead of 20, a Flite Ti saddle, and softer bar tape took care of most of the ride issues.. so I agree that holding off on the fork change until the stem and other changes are made is sensible.

But after that, carbon does also make sense, you may just be more sensitive to the buzz than I am. See the inimitable Sheldon's site,
http://www.sheldonbrown.com/rinard_forktest.html
for Damon Rinard's tests of various forks, where he also says:
"Is there more to comfort besides deflection?
Yes. There are two sources of discomfort in the road: gross bumps (like potholes or reflector dots you hit at speed) are one. The other is the smaller texture of the pavement itself. This texture produces a high frequency buzzing in the handlebars that is constantly present.

The gross bumps can be made more bearable with a fork that flexes a little more. For extremely bumpy roads (like Paris-Roubaix), there are even suspension forks. But the second source of discomfort, the constant vibration, is harder to address. About the only way a normal road fork can lessen them is by the natural damping properties inherent in the material used to make the fork.

Road forks are made of steel, aluminum, titanium, and carbon. Of these, carbon is known to damp vibrations about ten times better than the metals. This damping is the reason carbon forks can be both stiff and comfortable. You will still get the jolt of the big bumps with a stiff carbon fork, but the vibrations will be decreased. And a flexible carbon fork is really plush.

If you ever get the chance, try an experiment to experience the difference in damping: ring a carbon fork (like a tuning fork) by slapping it once into the palm of your hand and hold it near your ear, then compare it to a metal fork. The carbon fork damps out the vibrations within seconds, but the metal fork vibrates noticeably longer. Another good illustration of composite's damping compared to metals is a handrail. A metal handrail, if struck, will ring and vibrate for several seconds, but a wooden one (wood is nature's composite) just goes ìthunk.î"