Bicycle Mechanics - How Do You Convert The Dahon Jack Into A Road Bike?

I want to turn the original Dahon Jack from this

http://www.metaefficient.com/wp-content/uploads/dahon_jack_urban-utility.jpg

into this...

http://youaretheengine.files.wordpress.com/2009/11/dahon2.jpg

http://youaretheengine.files.wordpress.com/2009/11/dahon3.jpg

anyone know what parts would I need? What about the gear shifter?
This is how the handle bars look like originally FYI
http://farm4.static.flickr.com/3169/2414037420_a50980cfed.jpg

I'm a noob so I don't know the names of the parts pictures or links would be best for me, Thanks! :)

PS: Can I put 700c road bike tires on the Dahon Jack?

They didn't change the shifter at all. The moved the standard grip shifter onto the end of the drop bars.

I can't tell if they changed the rims, but it looks like they changed the tires to (a winter tire in the picture, but otherwise.. ) slicks for easy city riding. They also changed the handlebars to road bike style drop bars. They had to change the standard brake levers to drop bar style brake levers. It looks like they bought a pair that use the same cable though, because You can see the cable coming out from under the bar tape, and into the horozontal brake levers.

I might've missed something, but those are the things that jump out to me. I'm a newb too, but I've done the tire change on my mountain bike, and I've considered doing the drop bar change as well. I settled for Bar ends though.

The HubBub bike shop in Ohio designed the bar end adapter, and seems like they can be gotten thru many bike shops, now. even in England http://www.sjscycles.co.uk/product-Hubbub-Hubbub-Drop-Bar-Adaptor-Mount-for-Rohloff-Handlebar-Twistshifter-73-mm-11233.htm

the other thing is straight bars are smaller in the center than road bars, 1" vs 26mm, so a stem swap may be in order..
V brake road levers if you have V brakes..
the larger diameter of road bars in general is why that drop bar adapter was made,
On the end it is the same diameter as the 7/8" tubing of MTB bars.

For 700c tires you need to buy a different bike. from Dahon, also, are these : http://us.dahon.com/bikes/1672/tournado

Here's what I see you'll need (many already listed above)

-Drop handlebar
-Handlebar tape
-Stem (may want a shorter and/or taller one than current)
-V-brake compatible drop brake levers http://www.sjscycles.co.uk/product.asp?pf_id=14956&src=froogleUS&currency=USD
-Cross/Interruptor brake levers (if you want them; personally, I wouldn't bother)
-Hub-bub adapter above
-New cables and housing (at least for the brakes; may not need for shifter)
-Slick 26" road tires and smaller tubes (If you currently use schrader tubes and want to use presta, get two grommets to reduce the valve hole of the rims. And hopefully the current rims are narrow enough to use as narrow tires as you want. If you want to replace the wheels, I think you'll be entering into "it's just not worth it" territory.)

There are other options for the shifters, but they'd be more costly, difficult, and time-consuming than the above.

What is your goal for how this bike will ride after doing some upgrades? Is the idea just to get into a different riding position and get more options for hand positions? Or is it because you think it'll be fast like a road bike? Or do you just like the look of the drop bars? Be honest now..... Being honest with us would be nice but more importantly be honest with yourself. And what can you spend on this as a budget?

What is your goal for how this bike will ride after doing some upgrades? Is the idea just to get into a different riding position and get more options for hand positions? Or is it because you think it'll be fast like a road bike? Or do you just like the look of the drop bars? Be honest now..... Being honest with us would be nice but more importantly be honest with yourself. And what can you spend on this as a budget?

i like the look of the drop-bars...i like the speed of the thin wheels...i like the different riding positions and more options of hand positions....and most important of all I love the convenience of folding the bike taking it with me to work instead of locking it in the street and folding it and putting it in the trunk of my car.

For 700c tires you need to buy a different bike. from Dahon, also, are these : http://us.dahon.com/bikes/1672/tournado

$2500....

wow thanks !! your information is much appreciated ! =D


Here's what I see you'll need (many already listed above)

-Drop handlebar
-Handlebar tape
-Stem (may want a shorter and/or taller one than current)
-V-brake compatible drop brake levers http://www.sjscycles.co.uk/product.asp?pf_id=14956&src=froogleUS&currency=USD
-Cross/Interruptor brake levers (if you want them; personally, I wouldn't bother)
-Hub-bub adapter above
-New cables and housing (at least for the brakes; may not need for shifter)
-Slick 26" road tires and smaller tubes (If you currently use schrader tubes and want to use presta, get two grommets to reduce the valve hole of the rims. And hopefully the current rims are narrow enough to use as narrow tires as you want. If you want to replace the wheels, I think you'll be entering into "it's just not worth it" territory.)

There are other options for the shifters, but they'd be more costly, difficult, and time-consuming than the above.

yeah, I see the cable on the left side of the picture but not the right. is the right brake lever on the drop bar just for show? or is the cable inside the handle bar?


They didn't change the shifter at all. The moved the standard grip shifter onto the end of the drop bars.

I can't tell if they changed the rims, but it looks like they changed the tires to (a winter tire in the picture, but otherwise.. ) slicks for easy city riding. They also changed the handlebars to road bike style drop bars. They had to change the standard brake levers to drop bar style brake levers. It looks like they bought a pair that use the same cable though, because You can see the cable coming out from under the bar tape, and into the horozontal brake levers.

I might've missed something, but those are the things that jump out to me. I'm a newb too, but I've done the tire change on my mountain bike, and I've considered doing the drop bar change as well. I settled for Bar ends though.

Thought of something else. If you don't use cross/interruptor levers, you may not have a barrel adjuster. You can replace the v-brake noodles with ones that have a built-in barrel adjuster: http://www.amazon.com/Origin8-V-Brake-Barrel-Adjuster-Noodle/dp/B003BCG8Y6

yeah, I see the cable on the left side of the picture but not the right. is the right brake lever on the drop bar just for show? or is the cable inside the handle bar?

There are three cables. One for each drop and cross brake lever pairing and one for the shifter. Edit: the brake cable starts at the drop brake lever, runs under the tape, through the cross/interrupter lever, and out to the brake.

Thought of something else. If you don't use cross/interruptor levers, you may not have a barrel adjuster. You can replace the v-brake noodles with ones that have a built-in barrel adjuster: http://www.amazon.com/Origin8-V-Brake-Barrel-Adjuster-Noodle/dp/B003BCG8Y6

what are barrel adjuster? you seem like you know what you're doing, so if you say you wouldn't bother with the cross/interruptor levers than I probably wouldn't too...what is that anyway?

for the 26" slick tires, which should I get ? 26 x 1.5 ? 26 x 1.3 ? can I get like...26 x 1.0? or the rims are too wide?

it seems like he used the original stem, if you look at it carefully the letters on it matches the original. And it looks like he used the original brake levers for the drop-bar levers...as it appears to be black...can anyone read what it says on the black levers ?

what are barrel adjuster? you seem like you know what you're doing, so if you say you wouldn't bother with the cross/interruptor levers than I probably wouldn't too...what is that anyway?

Barrel adjusters allow you to fine-tune the length of the cable housing which adjusts the relative length of the cable. This allows you to fine-tune how far away the brake pads sit from the rim, which allows you to set how much travel is in the brake lever. Basically it lets you fine tune all this after you've first setup the brakes in the ballpark of where they should be.

I wouldn't bother with cross/interrupter levers because, for me, the only times I'm in the tops of my drop bars is when I'm climbing or cruising, both times access to brakes are not needed so quickly.


for the 26" slick tires, which should I get ? 26 x 1.5 ? 26 x 1.3 ? can I get like...26 x 1.0? or the rims are too wide?

You should measure the inner width of your rim. You can use this chart as a guide: http://sheldonbrown.com/tire-sizing.html#width

1" = 25.4mm. 1.3" = ~33mm. 1.5" = ~38mm. Road bikes usually have 23 or 25mm tires, but I use 28mm because I'm heavier. 32mm and larger is common for touring.


it seems like he used the original stem, if you look at it carefully the letters on it matches the original. And it looks like he used the original brake levers for the drop-bar levers...as it appears to be black...can anyone read what it says on the black levers ?

It may be the original stem. However, as someone mentioned above, most flat/MTB bars and corresponding stems have a clamp diameter of 25.4mm, which is slightly smaller than drop/road bars/stems at 26.0mm. A debate about whether it's okay to mix a 25.4 stem with 26.0 bar crops up every once in a while. Personally, I've seen it lead to a pinched bar that I was no longer comfortable using.

Besides, going from flat to drop bars will significantly change the feel of the bike and you may find a new stem is needed to bring the bars closer/further or higher/lower.

Guarantee the levers, either of them, are not the original levers. There are many reasons they could not be. The drop levers say the brand "Tektro" on them. I think they're the same as the ones I posted above.

Ok its not like coverting , but you cannot make a huge jump in wheel sizes, 559 to 622 and have the Brake pads hit the rim.
if you are starting out with a disc brake bike its possible
but rim brakes forgetaboutit.

Buy another bike

the one i mentioned does knock down to a small case

S&S connectors [surly travelers check] or a Ritchey Breakaway frame,+ buy a groupset for retail, and it costs more..

Ok its not like coverting , but you cannot make a huge jump in wheel sizes, 559 to 622 and have the Brake pads hit the rim.
if you are starting out with a disc brake bike its possible
but rim brakes forgetaboutit.

Buy another bike

the one i mentioned does knock down to a small case

S&S connectors [surly travelers check] or a Ritchey Breakaway frame,+ buy a groupset for retail, and it costs more..

There are 26" slicks.

The S&S connectors require a tool to break down the bike. While it does make for a compact travel package it's not really in the same convienience league as a folder such as this Dahon.

Your best bet for wheels is to stick with what you have and check the width of the rim to see if you can sneak on a 26x1.0. Likely you can since the wider MTB rims are almost all intended for light to heavy jumping and the extrusions used for less demanding riders are all the same extrusions as used by a lot of road bike rims.

For commuting I can heartily recomend Panaracer Pasela TG tires in 26x1.25. They seat on the rim with a decidedly egg shaped fit where the point of the egg is the tire tread. This produces a more narrow road interface more in tune with what you'd get from a 23mm road tire. And the TG (Tour Guard) kevlar belt really does reduce or eliminatee flats.

Dahon Licensed, paid a royalty to Tom Ritchey, for the Break away system.. a band clamp joins 2 flared tubes in the down tube.
not unlike irrigation piping on the farm uses,
the other joint breaks open when you remove the seatpost.

that's how the Tournado comes apart to pack in the travel case ..

+1 Go to Sheldon Brown site for rim/tire limitations. I use the 26 x 1.25 slicks on my mountain bikes. Works great. Nashbar has them on sale right now for $10 each.

What I don't understand is there is only one brake line for the front brakes and one brake line for the rear brakes. So how will all four brake levers work? or does only two work and the other two doesn't work?

Dahon Licensed, paid a royalty to Tom Ritchey, for the Break away system.. a band clamp joins 2 flared tubes in the down tube.
not unlike irrigation piping on the farm uses,
the other joint breaks open when you remove the seatpost.

that's how the Tournado comes apart to pack in the travel case ..

You have no idea what you're talking about.

The Dahon jack does not use any sort of ritchey breakaway system. The top tube is broken in two sections which come together in a plastic plug type system and is not 'secured' in anyway. The lower downtube system is a hinge system with a dahon latch. There are no band on clamps anywhere on the frame. The seatpost also does NOT need to be removed to break open another joint. There IS NO JOINT.

Seriously people, stop making **** up. We sold those bikes and we repaired those bikes as an official dealer.

Cross levers use the existing brake cables, they go in the middle.

You can sorta see it in this:
http://www.bowcycle.com/bikes/blogs/viks-picks/wp-content/uploads/2009/05/bbc-brake-levers.jpg

The cable housing from the aero levers runs into the cross levers, then out again and to the brakes.

What I don't understand is there is only one brake line for the front brakes and one brake line for the rear brakes. So how will all four brake levers work? or does only two work and the other two doesn't work?

The housing is spliced around the secondary brake levers, and the brake cable runs through them freely. These levers push on the housing while the cable is held in place by the main brake, which has the same effect as pulling on the cable while holding the housing in place (like on a normal brake).

you're a genius !! so I should buy the aero levers instead of the tektro 520 right? but where does my shifter go? can i slip it inside the drop handlebar?


Cross levers use the existing brake cables, they go in the middle.

You can sorta see it in this:
http://www.bowcycle.com/bikes/blogs/viks-picks/wp-content/uploads/2009/05/bbc-brake-levers.jpg

The cable housing from the aero levers runs into the cross levers, then out again and to the brakes.

I wouldnt bother with interrupter levers, as I only put my hands on that part of the bar when stopped at traffic lights, or when coasting. If the reach and height for the straight bars are good for you, then you will probably want a different stem to put the bars a bit higher and closer to you.
Before putting on drop bars, change the tires and tubes, and put on bar ends to approximate the hoods riding position. This can be done with very little cash outlay. You may then find you need a bigger chainring. Then you can start thinking about the expensive options, including brifters.

If you don't want the interrupter levers then you can still have fine adjustments for the brake cables. Use an inline or a cable stop adjuster. I'm sure you can get them at many places but the first one to pop up from my search was Harris Cyclery. I'm guessing that the inline ones would be best since I'm assuming that a folding bike uses full length housings.

http://www.sheldonbrown.com/harris/cable-hardware-brake.html

Something I haven't seen mentioned yet is that road drop bars will not accept the smaller diameter mountain bike shifters or brake levers. So that fellow that mounted the twist grips to the ends of the drops must have used a custom stub that he insert into the bar end or he somehow reduced the bar diameter for enough distance to jam the twist shifter onto it. It's not just a small amount either. So you either need to opt for something equally as custom or opt for the more expensive brifter levers.

Or you could do like a few of us have done and find some rapid fire click pod shifters. The mounts are not that hard to remove and work the opening larger with something like a Dremel and a sanding drum. In my case I've got a metal lathe so I clamped the mounts in my four jaw, centered the opening and bored them out. To install them they sit in near the center just inside of the bar end tape. So interrupter levers are not an option then. The pods are slightly staggered so the cables exit past the opposite pod without too much of a bend.

By the way, speaking of a custom part to fit the shifter if you go back to the original picture of the drop bar bike you can see that there is a small light brown stub sticking out the end of the twist grip. I'm betting that the "custom stub" is nothing more than a chunk of hardwood dowel that the guy shaped for a tight jam or glue in fit into the bar and then sized the rest to let the twist shifter fit over the stub.

I also just double realized that you only have one shifter. So if you choose to go shopping for one of the pod style rapid fire shifters and hog out the mounting hole to fit the drop bar then you would only have the one shifter in by the stem instead of two. That would make for a cleaner install.

Frankly my own tastes would lead me to getting the pod shifter and have it in by the stem. It's easy to reach from any of the usual riding positions instead of having to reach down to the end of the drop. It is also better protected from crash damage or just handling bumps and scrapes for both the pod and the cable.

And since you've got V brakes you still need to get the levers that are V brake compatible for length of cable pull. So you're still stuck with the Tektro 520's or something similar.