Just to chime in with my 2 cents. I have a 700c Road bike. What is currently limiting me on the Swift is the upper gearing and tire selection. Granted there is a slight (3% according to Xootr) rolling resistance penalty to smaller wheels, but what I really need is a set of 120psi tires and an approx. 110-120 top gear inch to better compare to my road bike. 95% of the time I'd say I average the same speed as my road bike.

I've actually setup the bar position to be more aero since the height is limited and I'm at the upper end of the height limits of the frame. Creating the chart has been helpful because I have done some additional calculations and come to the conclusion that a sub 20lb bike would be very difficult given the parts. This has helped me from a planning perspective. The thought was to have a bike as light as possible. The upgrades I have made have put the bike at the same weight as my Giant road bike (alu frame).

My final upgrades will attempt to push the bike closer to the road bike so I can either sell it or pass it along somebody else. I am already putting in 85% of my rides on the swift.

Really, the easiest way to go sub 20 is to go the james_swift route -- fixed gear, no rear brake, and minimal handlebars.

Does the 280g include the Quick Release and skewer weight? Don't forget that adds 35g

edit: nevermind, now I see what you're doing. Let me know how that works!

Hey, quiet there in the peanut gallery. I just washed it today as it's been raining off and on this weekend. (Can you believe it ... in LA?)

Lots of good information in here. Gives me a lot to think about when toying around with the idea of dropping the bikes weight.
Here's my contribution. I was in a recumbent shop looking at 20" wheels, and I noticed some forks they had. Well, this one fork was all carbon fiber, including the steerer with v brakes posts. I don't know the weight of the fork, but it was light, and looked really cool, since the blades were aero. The mfg is velokraft (I think) but the price of the fork is $350!!! Dang, with that much money you could buy another frame. Anyway, just thought I would let ya'll know there may be a fork alternative out there.

Let's see. Advertised at 350g. Previous posters have put the steel fork at 870g. 520g/1.14lb difference makes for a significant savings. Now, who's brave enough to put a carbon fork on a folder???

There are some light(er) BMX forks out there.

You could try a pair of Schwalbe Stelvios, they're probably the fastest / highest pressure 406 tires.

Personally I think the ride on that would be unadulterated punishment, though....

I'm not familiar with BMX bikes, or their forks. would you care to share some examples of a lighter fork. Although I don't see myself changing the fork in the near future, it is always nice to know.

big boy phil,

There are bmx forks for racing that are actually carbon. Only problem is, they are made for bmx racers. In other words, if you resemble your forum handle, you may not be able to use them.

Juan

And here's where I say, "Right On." I purchased my Swift/Xootr as a frameset, so that I could set it up as a road machine. That's an option for anyone--if you can get ahold of Peter! My position is the same as on my 700c road bike (which has a 72.5 deg. seat angle, by the way--I don't think 75 degrees is very common except on tri/time trial bikes, at least in my 55cm size), so that's a non factor.

I just switched to the IRC Metro tires touted in another thread, and they are significantly more comfortable than the Stelvios I had been using. For rides under 4 hours, the comfort thing isn't significant for me. It's comfortable. I think frame material is less significant than frame design and tires in terms of comfort. I believe I feel vertical compliance in my Swift that I don't feel on my steel road bikes. The handling isn't quite as stable, and that is a factor.

I've got a ten mile time trial course near by, and will try to do multiple runs on my Swift and 700c racing bike to see how they compare. Can't say conditions will controlled enough, or that they'll be enough test runs for it to be particularly scientific. But it should be interesting. I'll do it a couple of times over the course of a couple of weeks, and I'll try not to predict the results so that I can keep an open mind. And no, I don't have and don't intend to buy a heart rate monitor or power meter. But I won't say no to donations!

Jack

This will be very interesting. I'll keep an eye open for the results.

jack - if you dont mind, could you list your bikes specs?

Sure--take a look at post #3 in this thread. Only the tires have changed. I plan to compare it to my other fixed gear bike (700C), and will take racks/bags off for that purpose. Getting the gearing identical will be hard--both are in the 70" range, but I'll see how close I can get them by swapping cogs and even tires if necessary.

Jack

Is that right? Do they have a weight limit? Or did I just miss a joke?

I like this one...

https://www.triathlete.com/store/product.php?id=29477

Some carbon fiber BMX forks do have rider weight limits that are fairly low... i.e. for kids.

I am only interested in carbon fiber forks for their looks, since unicrown forks look bland and generic. the weight loss of going with carbon is a nice benefit. Just dont want to spend a weeks pay to get one.

Back to the question of whether a Swift is as fast as a road bike?
(Are we talking block-long sprints, or centuries?)

Only the man who owns both bikes, and sets them up with identical gearing, and tests them honestly will have any clue for sure. It sounds like you can provide a hint of an answer.

Personally I'm skeptical that a Swift is really all that swift... but hopefully I'll be proved wrong. It's a nice fantasy... I'd like to believe I could potentially keep up with the big kids on my twenties.

Hmm. Maybe that's good advice.

Eeeeek!!




^ What is this????!!!!!!!!!!!

Did you stuff your Swift?

[edit] sorry stupid question. Was the seat post too short? What happened? I am running scared. I just finished my seatpost mods, haven't ridden it yet, but now I don't want to touch it until I know what happened with yours. Mate, my sympathies.

Looking at the geometry, it becomes obvious (with hindsight) that the seatpost is an integral, essential part of the seat tube strength. The loaded frame forces impose a shear force on the seat post. I guess that's why carbon would not be a good idea.

Watching this thread with anxiety...

kb5ql, Wow, that is some frame break!

big boy phil, I wasn't kidding about the weight limit. It's what kept me from buying one for my Raleigh Twenty.

Juan

Oh man...I hate to say it, but....nahh, I won't....

Sorry to see that happen to your Swift. Man, the paint is even still factory fresh. So I take it the frame failed while you were riding it. I hope you didn't take a spill.

For kicks, I tried fitting my Dahon VD5 post in my Swift. With both clamps tight, the rear triange pivots forward about a millimeter when I lift up the back of the bike by it's seat, which probably means that the Dahon post is not the same diameter as the Swift post (even though they're both stamped at 34mm).

Yep, sounds about right. I purposely posted in this thread to avoid you ... The new one is coming with the extra long seatpost. We'll see if that fixes the problem. (currently wiping egg off face)

So many questions... I hope you have time to answer them all for the sake of the quick and the dead here...

1. New frame? Did you already order a whole one? Not only the rear triangle?

2. By going in the previous posts, you were using a Dahon Vitesse seat post that is apparently smaller...?

3. Did that seat post fail as well, or just the frame?

4.What is you weight?

That will do for now.

I will try to answer your questions:

I have a whole new bike. It appears they have increased the thickness of the aluminum tubing on the latest batches while retaining the same inner diameter.

I was using a Dahon Speed P8 post as the stock one was way too small. (6'3"/190.5cm tall)

The seat post is fine. Actually the frame broke as I was unfolding and attempting to put the post back in. I'm guessing the tubing was already fatigued. There was the slightest bit of play in the last week leading up to the break lending credence to James_Swift's suspicion of the seat tube not being exactly the same diameter.

195 lbs. / 88451g

OK.

Thanks, for the answers!

I'm glad to hear you have not written off twe Swift as a bike altogether.

The above answer immediately makes me wonder, could you post the tube diameters that appear different?

I am a little relieved for my own seatpost venture now, but still...

Details with pics to follow.