Folding Bikes - downtube modding

Bikeforums.net is a forum about nothing but bikes. Our community can help you find information about hard-to-find and localized information like bicycle tours, specialties like where in your area to have your recumbent bike serviced, or what are the best bicycle tires and seats for the activities you use your bike for.




View Full Version : downtube modding


deadpool
08-11-08, 11:10 AM
Greetings. I am am new to folding bikes (and basically bikes in general). I just got a downtube fs a few weeks ago and don't really like the weight of it. I want to do some cheap and easy weight reduction on the bike and I would like to know if I can use standard parts for it.

I just want to upgrade the pedals, seat, handlebars for now. Most likely I will take off the rear rack as I do not use it.

Any help would be appreciated! Thanks!


chagzuki
08-11-08, 11:23 AM
Surely the handlebars are standard cheap alloy ones, I'd imagine it would be hard to find a cheap replacement that shaves off much weight. But you'd have to know the current component weights if you want to make very savvy purchases.

JosephLMonti
08-11-08, 11:30 AM
Most likely I will take off the rear rack as I do not use it.

Do you mean "FS" as in "full suspension" or "front suspension"?


snafu21
08-11-08, 11:30 AM
I changed out the h/bars, stem, and brake levers on mine, because I have a disease of the mind. None of the new bits were any lighter than the originals, although I lopped 2" off the news bars for storage. Then, I added a GPs to make up for the weight loss.

The stock Downtube stuff is already quite light, unless you go for serious roadie stuff like Ultegra.

The easiest weight-ectomy is to replace the sus-forks with BMX non-sus items, but some of us like suspension.

mulleady
08-11-08, 11:36 AM
Downtubes aren;t especially heavy for what they are, for example compared to Citizen bikes.

Taking off the rack will shed some weight, as will getting a nice carbon seatpost and lightweight ti-saddle. I recommend the MKS series of folding or detachable pedals.

deadpool
08-11-08, 11:37 AM
FS as in front suspension- sorry for the discrepancy. Also, yes, I do not know what the actual weights of each component is, but perhaps someone here knows?

snafu21
08-11-08, 11:40 AM
Just go for 'pretty'. You get more for your buck:

mulleady
08-11-08, 11:42 AM
I changed out the h/bars, stem, and brake levers on mine, because I have a disease of the mind. None of the new bits were any lighter than the originals, although I lopped 2" off the news bars for storage. Then, I added a GPs to make up for the weight loss.

The stock Downtube stuff is already quite light, unless you go for serious roadie stuff like Ultegra.

The easiest weight-ectomy is to replace the sus-forks with BMX non-sus items, but some of us like suspension.



Snafu is that a universal GPS bike holder or one specific to that model? I am looking out of one for my Magellan Roadmate!

snafu21
08-11-08, 11:44 AM
It's for a TomTom. Came from Germany.

mulleady
08-11-08, 11:49 AM
Need one for a Magellan Roadmate 1200

chagzuki
08-11-08, 11:51 AM
Your handlebars look seriously narrow, mulleady: how wide are they & does it make any qualitative difference to the ride?

chagzuki
08-11-08, 11:56 AM
Deadpool, do you have a 2009 model?

chagzuki
08-11-08, 12:15 PM
On my Dahon I swapped the brake levers for the cheapest & lightest I could find which happened to be the Avid FR 5:

http://www.wiggle.co.uk/p/Cycle/7/Avid_FR_5_Brake_Lever_Set/5360013158/

JosephLMonti
08-11-08, 12:29 PM
Lose the suspension fork:

deadpool
08-11-08, 12:33 PM
Thanks for all the replies! That's quite a set up snafu! Very nice! I know that I will probably never get the weight down that much, but every little bit helps!

snafu21
08-11-08, 12:44 PM
That 'pretty bike' isn't mine, have a look through the forum, I've lost the link to the thread and a credit for the owner.

deadpool
08-11-08, 03:54 PM
Also, the parts are standard- meaning I can just get basically any parts from say Nashbar or Performance Bike and they should fit, correct?

chagzuki
08-11-08, 04:20 PM
A question for those who have switched the front suspension for rigid:
The rigid forks on the Downtube site look fairly standard, i.e. like on a normal hardtail it'll change the geometry as suspension forks need as much extra height as is necessary to accomodate the travel and rigid forks don't. No big deal in terms of the ride, but what happens to the change in frame geometry when you fold the bike? The relative heights of the wheels will change and surely the bike won't balance properly. There must be somewhere between 5 and 7 cm difference in height between a suspension fork and a rigid one.

deadpool
08-11-08, 04:38 PM
A question for those who have switched the front suspension for rigid:
The rigid forks on the Downtube site look fairly standard, i.e. like on a normal hardtail it'll change the geometry as suspension forks need as much extra height as is necessary to accomodate the travel and rigid forks don't. No big deal in terms of the ride, but what happens to the change in frame geometry when you fold the bike? The relative heights of the wheels will change and surely the bike won't balance properly. There must be somewhere between 5 and 7 cm difference in height between a suspension fork and a rigid one.

Interesting. I would like to know this as well! I would like to keep the bike in similar geometry or at least as close as possible to the original geometry as possible.

Also, would putting on any platform pedals be feasible? fit easily?

chagzuki
08-12-08, 08:35 AM
There ought to be a sticky for cheap and lightweight component upgrades. I've ordered a digital scale which will arrive in a couple of days & I plan to do some investigating. I've seen quite a few cheap (<£15) handlebars that supposedly weigh around 150 grams or would if cut down to 56mm. But I don't as yet know how much the stock Dahon handlebars weigh.

deadpool
08-12-08, 12:20 PM
I second the cheap sticky!! I've seen a few cheap handlebars, pedals, brake levers etc. They also seem relatively lightweight as well, but of course without knowing how much the stock parts weigh, I wouldn't know if these would be good mods.

Oh, and chagzuki, I do have a 2009.

chagzuki
08-12-08, 12:48 PM
Get some scales, man, and develop an OCD type behaviour of weighing everything.