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Downtube folding bike

Old 03-21-07, 01:13 PM
  #1151  
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Originally Posted by DVC45
Anyone know if the Dahon Biologic Post Pump will work on DTs? ' seems like a good accesory to have.
A link is always nice:
https://www.dahon.com/technology/component/zorin.htm
https://shop.sunrisecyclery.com/item/14128
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Old 03-21-07, 01:25 PM
  #1152  
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Originally Posted by makeinu
BTW, does anyone else with the VIIIH notice that when you roll it forwards the cranks turn. It doesn't happen when I'm in direct drive. Does anyone know how to fix this?
FYI, mine does not do this. Sorry, I don't know enough about internal hubs to advise how to fix this.
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Old 03-21-07, 06:17 PM
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Just check if the dahon post is 27.2mm, if it is, you're in great shape.
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Old 03-21-07, 07:03 PM
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Originally Posted by BigMacFU
Just check if the dahon post is 27.2mm, if it is, you're in great shape.
I believe all Dahon's have a 33.9mm post.

Thanks,
Yan
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Old 03-21-07, 07:33 PM
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I checked their website again and found out that the 27.2mm ones fit their larger folders (Matrix, Cadenza....), So I would think it would be too long for my VIIIH.
I think I want to order one and try it out anyway.

Last edited by DVC45; 03-21-07 at 10:52 PM.
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Old 03-21-07, 08:02 PM
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Soft or Hard Shell Case for traveling

I was reading earlier posts discussing the soft vs. the Samsonite Hardshell Oyster and the Flite.

I can't find any American Trunk and Case that has the dimensions listed by Mav & Jen
Posted by WrencherWOAC post number #1003
28" X 20" X 14"

I can't find anything current on the 'net that comes close to those measurements.
The one currently listed is:
28" Upright: (28" x 18" x 10", 10lbs)

Don't think this will make it work.
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Old 03-22-07, 06:07 AM
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First, regarding the magnets, how do you propose that they be attached? *The Velcro was a total failure, by the way! Don't bother with it!*

Second, regarding the suitcase, I agree. I was just in Thailand where there was a block long luggage store with great stuff. They didn't have anything that would fit the Downtube. It's just too big!

Third, I'm still having problems with autoshifting. Mine should be called the Downtube NS Automatic. I've removed and oiled the cables, reset them, etc. But the thing keeps shifting. I'm planning on going vodoo now, and doing things like swapping the derailleur for an Alivio I already have. Or dancing around a fire. But seriously, I'm reluctant to replace all the housing because it's in fine shape. Playing around with the routing seems silly to me b/c Yan must have experimented extensively to get to the current routing...

Finally, DVC 45, Don't buy the pump! Not only will it not fit, but you won't be able to mount it anywhere. We have enough trash in this world...I have a water bottle braze-on pump fit that's mostly unobtrusive and is lighter and works better than the biologic pump. And it was $5.
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Old 03-22-07, 09:11 AM
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Originally Posted by pm124
First, regarding the magnets, how do you propose that they be attached? *The Velcro was a total failure, by the way! Don't bother with it!*
How did the velcro/superlock fail? I'm still thinking of trying a weak "velcro" brand velcro along with large flat discs attached to the axle nuts (perhaps 2" in diameter or more). I'm hoping that the more spread out distribution of the gripping power will prevent the velcro from peeling itself off while at the same time making the whole setup more forgiving of inexact wheel positions. However, if your problem was, for example, dirt getting into the velcro and destroying it, then I won't bother.

The thing I don't like about the magnets on Dahons are that the magnets are too strong when you have it lined up perfectly, but a too weak when slightly offset.

Originally Posted by SesameCrunch
FYI, mine does not do this. Sorry, I don't know enough about internal hubs to advise how to fix this.
I readjusted the shifter cable and the problem went away.

Last edited by makeinu; 03-22-07 at 10:58 AM.
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Old 03-22-07, 10:11 AM
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Originally Posted by pm124
First, regarding the magnets, how do you propose that they be attached? *The Velcro was a total failure, by the way! Don't bother with it!*

Second, regarding the suitcase, I agree. I was just in Thailand where there was a block long luggage store with great stuff. They didn't have anything that would fit the Downtube. It's just too big!

Third, I'm still having problems with autoshifting. Mine should be called the Downtube NS Automatic. I've removed and oiled the cables, reset them, etc. But the thing keeps shifting. I'm planning on going vodoo now, and doing things like swapping the derailleur for an Alivio I already have. Or dancing around a fire. But seriously, I'm reluctant to replace all the housing because it's in fine shape. Playing around with the routing seems silly to me b/c Yan must have experimented extensively to get to the current routing...

Finally, DVC 45, Don't buy the pump! Not only will it not fit, but you won't be able to mount it anywhere. We have enough trash in this world...I have a water bottle braze-on pump fit that's mostly unobtrusive and is lighter and works better than the biologic pump. And it was $5.
Thanks for the heads up about the pump. ' just thought its a clever idea. Well, maybe not.

Regarding the suitcase issues, it seems to me, based on these posts, that the only DT that's rated for suitcase and airline travel are the Mini's......Darn, I thought I'm done buying bikes.
I have 3 bicycles now, since I started cycling last year.

I hope Yan can extend the sale on the Mini's 'til next month.
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Old 03-22-07, 03:25 PM
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Hi makeinu, it fails by peeling off. I even reinforced it and wrapped it entirely around the QR lever. Your idea might work better if you can get them to approximate perfectly.

I'm just on my final mods. I have the NS down to about 25 pounds. However, I can't manage to flip the stem as Yan suggested. I loosened the bolt and whacked it with a rubber mallet, but the thing is still on there good.

Also, my headset is kaput, so I need to take the stem off to re-grease it. Any thoughts?
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Old 03-22-07, 03:43 PM
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Originally Posted by pm124
I loosened the bolt and whacked it with a rubber mallet, but the thing is still on there good.
Also, my headset is kaput, so I need to take the stem off to re-grease it. Any thoughts?
I had one that was kinda tight. I just forced it and it eventually came off. There's nothing in there that would be damaged from using some force (maybe a twisting force) to loosen it. Good luck!

As a preventive measure, I cleaned and re-greased the headsets on all 5 DTs that I bought. Easy to do and good insurance.
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Old 03-22-07, 07:42 PM
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Thanks Sesame! (I hope you don't mind the informality.)

I'm a weakling, but I'll try. So, it just works like the old fashioned stems, then but gets a touch tight.

Here are the specs on my GF's NS ("Mina Loy"), all savings very rough since I don't have a scale:

-Marathon Racers (-150 to 200gm)
-MKS pedals (QR, allows them to fit in the canvas bag in a pinch -150 to 250gm)
-Sawed off toe clips (+30gm)
-Nashbar OEM of the Velo Crossbow seat (- 500gm)
-Tien Hsin BB 113 square taper (-150 gm)
-105 Chainrings (53t as outer chainguard -100gm)
-Dotek cranks (-200gm)
-Removed all the extra stuff except reflectors (-250gm)
-Added lights, pump, tools (+250gm)

It's still too big to fit in a Dahon slip cover, but I do have a solution to the folding problem; I'm going to make a nylon slip cover a touch larger that will still hold the bike together. Doesn't ride as well as my Birdy, but not bad!

I donated all the parts to "Times up," a bicyling advocacy group.

[Edited in order to add details.]

Last edited by pm124; 03-23-07 at 08:45 AM.
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Old 03-23-07, 10:44 AM
  #1163  
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Someone by the username of Eric has converted a VIIIH into the Cruzbike recumbent. Here's a pic:


Details here: https://alysion.org/peba/index.php?topic=4.0

Sounds like it was quite an involved build - lots of problem solving and customizing. But the end result looks great!
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Old 03-23-07, 10:58 AM
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Sesame, do your legs/knees hit the handlebars when you pedal? How tight a clearance is it for you?
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Old 03-23-07, 11:08 AM
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MSK pedals

I hummed and hawed about getting me some quick release pedals and decided on using some old Shamano clipless that don't stick out very far and I have been very fun to use.

The lightest MSK pedal for the best price I found was here.
https://www.calhouncycle.com/productc...?idCategory=22
Never dealt with these folks, but the lightest quick release pedal is the EZ-MT at a claimed 323 grams.
At $59 that is the best price I could locate.

This MKS also has a quick release clipless pedal, problems are it takes it own special cleat (I like uniformity, so it should be shimano compatible cleat) ,it weighs somewhere in the 400's, and it cost over $100. I don't have the link with me but it is out there. The great thing about these quick release pedals is that you can buy extra mounts/ pedals and swap them. I have seen on the bikefriday yak forum positive reviews and a single negative review on another site. I would really like to hear PM124 about your experince with your MKS pedal.

On another note I swaped out my crankset last night and put on a double 53/39. Greased the bottom bracket (it needed it) I can only pull out on the drive side for lack of tools. So it weighted in at 245grams plus the unknown weight of the other cup. I'd guess somewhere around 280's to be optimistic. I'll probably go buy the tool and get a better weight later on.

NS 9
Crankset weight 838 grams (W/O bolts includes ring and plastic protector).

Last edited by Baldone; 03-23-07 at 03:18 PM.
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Old 03-23-07, 11:35 AM
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Hi Baldone,

Wow, so you are estimating that the crankset only weighs 1Kg including the BB? My savings weren't so great. I think mine weighs in around 850gm, but partly because I kept the outer chainring on. Anyway, not a big deal so long as my GF can lift it.

Anyway, the pedals are generally very nice. They are much heavier than similarly priced pedals in part because the axle locks into a stub. If it's raining and muddy, it tends to get into the mechanism, making it difficult to properly re-attach the pedals.

Of greatest concern is that if the mechanism isn't locked in properly, the pedal can fall off, causing a serious accident. One has to be especially careful when they are gummed up, because they can seem like they are locked in place, but then fall off later.

You are thus probably best off sticking with low profile pedals. By the way, has anyone ever checked out the profile of the Speedplay Frog relative to Egg Beaters? I'm thinking about upgrading my Birdy to one or the other. Because the Birdy folds up into both horizontal planes, it doesn't need QR pedals. But if they stick out, it does make the bike bigger. Ideally, I'd like to keep the pedals on when packing it in an Oyster.
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Old 03-23-07, 12:41 PM
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Originally Posted by bookishboy
Sesame, do your legs/knees hit the handlebars when you pedal? How tight a clearance is it for you?
It did initially when I had my seat placed further back. I eventually moved my seat up forward so that my knees are clearly in front of the handlebar (with my stem pointed towards me). This also helped with the weight balance on the bike, and allowed a more reclined riding position for aerodynamics. The picture earlier in this thread of me with my son in back is where the handlebar currently is set up. You'll be able to see my seat position and the knee clearance on that picture.

My handlebars are still not optimal, though. It places my bars too close to my body. I plan to get some of those curved Nitto bars which will allow 1) the knees to fit under, and 2) my hands further out for better leverage.

Is that your bike that I posted?
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Old 03-23-07, 02:12 PM
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Originally Posted by pm124
Hi Baldone,

Wow, so you are estimating that the crankset only weighs 1Kg including the BB? My savings weren't so great. I think mine weighs in around 850gm, but partly because I kept the outer chainring on. Anyway, not a big deal so long as my GF can lift it.

You are thus probably best off sticking with low profile pedals. By the way, has anyone ever checked out the profile of the Speedplay Frog relative to Egg Beaters? I'm thinking about upgrading my Birdy to one or the other. Because the Birdy folds up into both horizontal planes, it doesn't need QR pedals. But if they stick out, it does make the bike bigger. Ideally, I'd like to keep the pedals on when packing it in an Oyster.
Hello,

My crankset weight is at 838 grams exact. (left and right crank arm, chainring, chainring plastic thing, and chainring bolts = 838g) I guessed the BB, I could be way off, 275-300g seems reasonable and Yan said that he put in a lighter bottom bracket on his newer models, mine is a 2006 1/2.

I read somewhere (maybe this post who knows) where someone is using the speedplay. I think maunakea might have some on his bike maybe you can measure how far they stick out? The speedplay is king when it comes to low profile. I own some egg beaters and prefer those. So I will measure the length on mine when I get home. I know speedplay is shorter than the eggs.

I did look at a friends speed play and I believe that one of their models have a larger platform than the others, so that should also cause them to protude further than the standard SP model. If you are a weight weeine when comparing Speed Play to Crank brothers egg remember that speedplays cleats are 129-132g verses Crank Bro's 40g MT 60g road.

Found in my notes that the MSK Clipless is a claimed 415g. Its too bad the MKS isn't a more solid performing pedal, I think it is a great concept. It would be a theft deterent as well, a bike with no pedals just a small stub is pretty hard to ride away on.
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Old 03-23-07, 04:52 PM
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Originally Posted by SesameCrunch
My handlebars are still not optimal, though. It places my bars too close to my body. I plan to get some of those curved Nitto bars which will allow 1) the knees to fit under, and 2) my hands further out for better leverage.
Sesame,
You might want to consider what Rans has to offer for bars:

https://www.shoprans.com/products.asp?cat=16
https://www.shoprans.com/proddetail.asp?prod=HOTRODROCK

or Evo bars:
https://www.calhouncycle.com/productc...&idproduct=265
or
https://aebike.com/page.cfm?action=de...=30&SKU=HB2086

Last edited by EriktheFish; 03-23-07 at 06:21 PM.
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Old 03-23-07, 04:56 PM
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Hi Baldone,

Many thanks for checking. The Wellgo pedals I have on the Birdy now protrude 80mm from the insertion point on the crank. (These pedals weigh in at 260gm, but they are fussy to get into.)

Thanks,

Peter
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Old 03-23-07, 09:08 PM
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Well, Friday has come and gone, and no delivery of the Downtube IX NS.

Has me feeling pretty down. Even things I ordered through UPS ground on Tuesday evening arrived today. My note from Yan said it would be shipped out first thing Monday, March 19th.

That doesn't leave much prep and riding time with full time work this coming week. I leave with my friends to pick up his Bike Friday Pocket Llama next Saturday. I still plan to test ride a steel Swift, and visit the Co-Motion factory before we take off for a 5 day mini-tour west of Eugene, OR and the Pacific Coast.
Looks like I'm going to have to bring my full size touring rig instead. Real bummer for the Spring Break.
Lyndon

I'm with the whiners that it couldn't hurt Downtube to supply a tracking number.
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Old 03-24-07, 08:23 AM
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Originally Posted by SesameCrunch
It did initially when I had my seat placed further back. I eventually moved my seat up forward so that my knees are clearly in front of the handlebar (with my stem pointed towards me). This also helped with the weight balance on the bike, and allowed a more reclined riding position for aerodynamics. The picture earlier in this thread of me with my son in back is where the handlebar currently is set up. You'll be able to see my seat position and the knee clearance on that picture.

My handlebars are still not optimal, though. It places my bars too close to my body. I plan to get some of those curved Nitto bars which will allow 1) the knees to fit under, and 2) my hands further out for better leverage.

Is that your bike that I posted?
Definitely not my bike, though I admit I'm interested in trying out a 20"-20" SWB recumbent.
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Old 03-24-07, 10:15 AM
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Originally Posted by LuckyLyndy
Well, Friday has come and gone, and no delivery of the Downtube IX NS.

Has me feeling pretty down. Even things I ordered through UPS ground on Tuesday evening arrived today. My note from Yan said it would be shipped out first thing Monday, March 19th.

That doesn't leave much prep and riding time with full time work this coming week. I leave with my friends to pick up his Bike Friday Pocket Llama next Saturday. I still plan to test ride a steel Swift, and visit the Co-Motion factory before we take off for a 5 day mini-tour west of Eugene, OR and the Pacific Coast.
Looks like I'm going to have to bring my full size touring rig instead. Real bummer for the Spring Break.
Lyndon

I'm with the whiners that it couldn't hurt Downtube to supply a tracking number.
I don't know if you're taking delivery on the West Coast, but if so, by UPS ground, it's normally 5 working days from the East Coast where Downtubes ship from... if it was shipped Monday 19th, 5 working days would put it to you on the following Monday... I've had many Downtubes shipped to me, never a tracking number, all were 5 days to the SF Bay area.

Bruce
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Old 03-24-07, 11:33 AM
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I gotcha, Bruce. I was just hoping to dial this sucker in for the short tour. Just not going to happen.

BookishBoy:
If you are interested in a 20/20 'bent, you should check the ads for a Rans Rocket. Good bike. I have a Bachetta Giro 26/20 and enjoy it, except for steep hills.
Also, there is a guy in the NW, who sells Taiwan? 'bents. www.ActionBent.com
https://www.actionbent.com/ASSEMBLY_M...ABRoadster.htm
Adjustable suspension...hmm...if that works, that is sweet.
An excellent buy.
I don't know how much a new Rans Rocket costs, but I would sure look used, and maybe post at BentRiderOnline.com If I was looking for a 20/20 I would go this route. Hostelshoppe.com has their Volae series, which is nice...and some guy in Florida builds a simple version.
Finally, if you don't mind a longer wheelbase and a more upright position, check out the Granddaddy of 'bents, Easy Racer's Tour Easy. Sun and Cycle Genius also make some interesting stuff.
Gotta go, time to either rent or buy a tux for my buddy's wedding.
Get out and ride!
Lyndon
Salt Lake City
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Old 03-24-07, 12:44 PM
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My girlfriend bought a Downtube a few weeks ago with the notion of taking it on the bus/in her Miata and iding partway to an from work. Thus far this plan has not matrialised, but she has taken it out a couple of times when I've gone riding, and she was able to maintain a pretty good pace and she seemed comfortable with it. I suspect she's a little nervvous about actually putting the plan into practise.
Watch this space for updates...
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