sudoshift

owenfinn and I have Dahon Curve SL folding bikes. We've been trying to max out our speeds on flat roads just for the heck of it ever since the Top Speed on a Folder??? thread.



Let the speed challenge begin!

owenfinn

Ha! Bring it on!

The tale of the tape looks like the Capreo gives me just a bit more "reach".

Typhoon today, so I`m gonna rest up and have another go at that elusive 25mph barrier again tomorrow.

sudoshift

Typhoon eh? As you saw on my Flickr page, I tried doing a run today during lunch but it was just too windy. We'll give her a go maybe tomorrow.

Jiten

Excuses, excuses.

Go for the gold, guys! Don't let folder fans down!

fietsbob

Show the Math.. what is the gear ratio x wheel size?

invisiblehand

I thought that the Nexus 8 had a tad more than a 300% range. Maybe you meant 28" to 85".

owenfinn

For 3 smallest sprockets on the Capreo Curve SL I got -

16 x 53/9 = 94

16 x 53/10 = 85

16 x 53/11 = 77

A bit of a discrepancy from Dahon`s numbers which lists the top at 91. I wonder why.

Anyway, so far, the top speed for me was 39.4 kph (24.48 mph) which I hit spinning like mad in 7th gear before slowing down because of traffic.

So, when the quest for speed continues, the question is whether 8th and 85 gear inches is too big of a jump for my legs. I know 9th will slow me down on the flat because I can`t maintain the RPM.

We are in day 3 of rainy, windy weather in Yokohama but tomorrow should a good day.

BTW I have 1185 punched into my computer for the wheel circumference for the Marathon Racers. Any reason to think this is incorrect? I don`t really have time to roll it out.

just noticed the link below on google (but it`s firewalled for me so I can`t open it).

Place your bets?!?!
https://www.cyclebetting.com/cycling/...-igh-curve-sl/

sudoshift

"Excuses are like a** holes, everyone has one and they stink!" -- We will give it our best.

I'll get back to you.

I sure hope so! It might be, I can climb some pretty steep hills with relative ease. The lightness of the bike surely helps.

How did this get on cycling bets? LOL!

FYI: I also have my CATEYE computer set to 1185 and I believe we both have 16x1.5 Marathon Racers right?

I'll resume the 'challenge' after Comic Con is over on Monday!

sjdude

I too use 1185mm tire circumference for my 16" x 1.50 Marathon Racers on my curve.

You should use the true tire diameter instead of 16" in the GI calculation.

Tire circumference = 1185mm
Tire diameter = 1185mm / pi = 377.2mm (14.85")

For 3 smallest sprockets on your Capreo Curve SL you have-

14.85 x 53/9 = 87.45

14.85 x 53/10 = 78.71

14.85 x 53/11 = 71.55

owenfinn

Those numbers seem too low - plus if I actually physically measure the diameter with a tape measure I can see that it is definitely more like 15.5" or 39.5cm.

15.5 x 53/9 = 91.27 (which is the same # Dahon gives us)

so that seems about right. So if 15.5" (39.5cm) is the true diameter, let`s get the circumference.

395mm x pi = 1241mm

So it looks like that 1185 number for the Marathon Racer is way off.

Right?

samosaurus

Wow! You guys are FAST!

Sam

sjdude

Yes, you are absolutely right. The cateye manual seems pretty off the mark for the marathon racers.

I just measured a close 1226mm from a single revolution, give or take a few mm. This works out to a diameter of about 15.36".

15.36 x 53/9 = 90.45

bendembroski

The only way to do this properly is to do two runs in opposite directions on the same road and then average the results. This will account for wind / gradient. (Kind of.)

bjorke

The only way to do this really properly is to get corporate sponsorship for the race FIRST.

owenfinn

Operators are standing by!

Took advantage of the mild temperatures to have another go at glory, this time along the Tsurumi River near Nissan Stadium (I'll post a few photos later).

I was still in my work clothes and my backpack was still attached, like a sail, high on the seatpost. In addition, it was a bit breezy so tried to find a stretch that was screened by the high river grass.

With the computer still set at 1185 I blasted through 40.2 kph to 45.4 kph (28.2mph)!

The euphoria was short-lived however. Taking bendombroski advice I turned the bike around and set off in the opposite direction. This time I struggled to hit 34kph. It wasn't a strong wind but the backpack acting like a parachute was a killer.

Hope to have another go after work somewhere else.

owenfinn

45.4 kph - but with the wind at my back. Could only do 34 the other way.

Jiten

Woohoo!

sudoshift

Whoa what the hell man! 28.2 MPH!!! Very nicely done! Although using the backpack as a "sail" is questionable. I do envy your gorgeously smooth roads.

I tried a run today after work and I picked a spot that had a nice tail wind, my only problem was the the road was waay too bumpy and poor.


Proving Grounds Bumpy Roads by sudoshift, on Flickr

Every time I kept going up in speed I'd have to watch out for a crack or bump on the road. I'll have to try to find a new place. The roads here are horrible. Either cracks or too much loose gravel.

Once again topped out at 23.3 MPH


Nice View by sudoshift, on Flickr

I took it easy on this spot since there was loose gravel and I really didn't feel like falling face first into the rocks below.

Guess its safe to say that . . .

Round 1 Winner: owenfinn's 2009 Capreo Curve SL

owenfinn

Actually I didn`t feel that first wind-aided run along the river prooved very much.

Today was a beautiful day and I didn`t have to work, so I finally was able to ditch the office clothes and the big backpack to spend an enjoyable afternoon pedaling like a madman through the streets of Yokohama.

Managed to break through the 40.2kph/25mph barrier 6 times and hit a top speed of 43.6kph twice on 2 different roads.

The first attempt was on this road. Hit 43.6kph in one direction and then went the other way and got up to 40.9.

https://www.mapmyride.com/routes/view/43194366/







I think it is now safe to say - without doubt, the Capreo Dahon Curve SL is the fastest 16" folder on the planet.

LilGadgetGuy

Okay, sudoshift. You need to cut weight. Ditch stuff like fenders, silly bottle holders, and packs. Just wear a helmet and speedo!

Jiten

sudoshift, did you hear that? Are you going to let owenfinn get away with that claim?

LOL.

sudoshift

07/27/2011 by sudoshift, on Flickr

Okay let's not celebrate just yet. I only had time for a couple of runs. I need to find a different road. I am tired. . .

owenfinn

26.1 mph = 42 KPH - Nice one congrats!

OK - I will put down my bike.

bendembroski

Hey sudoshift, you do the two-run thing (one way in each direction)?

sudoshift

You might still want to keep the bike up there finnster, I don't think mine (either because of the bike's or my ability) can go higher than 26.1 MPH. I only managed to hit that once and for about two seconds. Which is why i still need to find a couple different roads.

It was neat that I was keeping up with this road race biker guy that kept turning to look back going "WTF." Then he speed off as I let up.

Oh I forgot to mention that, the way back I could get up to 23.8 MPH.

I came down with a bug so I'll have to resume the "trials" next week. Although i think the finn's Capreo will be hard to beat.