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Old 07-20-12, 01:44 PM   #1
ttakata73
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Join Date: Feb 2012
Location: Bangkok: hottest average temperature :(
Bikes: 1998 GT Forte Ti 700c, Brompton M2LX 16", Dahon Dove 14" (6kg)
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Dahon Mantis 16" review and Oyster suitcase pics

Hey guys, this is not available in the N.Am. market but I'm sure some English speaking folk in Asia read this forum.

Background & Competition:
So I got a Dahon Silvertip early this year because I hated the flexing in the 2 piece Dahon handleposts, but sadly the Silvertip is too big and cumbersome for me to deal with for travelling or commuting. Don't get me wrong I love the Silvertip because it is so fast and responsive, but its too big to be a practical intermodal folder. So instead of dumping money into it; I decided to look for a tiny new folder that I could realistically take on a train.
I test rode the Tern Link and loved its rigidity and ride, but that wacky rear derailler killed it for me. I like to modify and upgrade stuff and that forward mounted derailler can't be swapped with a SRAM Red. Sure I'd love a Verge or Vector, but my budget was a planned $500. Tern if you're listening; you are losing customers that can afford the Link but not the Verge. Smarten up and use standard components as much as possible or offer a Verge frameset.
With Tern out of the question, I wanted the Java X1 because it has 14" tires, disc brakes, can easily be modded to have 16" rims, multi-speed, and is only ~$360 here in Bangkok.
http://www.aimbike.com/newbike_view.php?id_prd=1582
Sadly the upright seating and super short wheelbase (~32") was so twitchy I just couldn't get used to it.
I also think the demo bike's handlepost was worn or just poorly designed as it flexed too much for comfort and this was after I tightened all the QRs and the handlepost linkage.
Dang, I really liked the look and portability of this bike, but it was too unsettling to ride.

The frame & ride:
So I saw the Dahon Mantis (meant for the China market) and loved the look of the frame. It has 16" tires, 8 speeds, V brakes, the dreaded 2 piece handlepost, and was $580. I test rode it and it felt much stiffer everywhere compared to the Java X1 and the handlepost didn't flex as much as I remembered when I had my 2008 Dahon Curve. This stock 2 piece handlepost is not as stiff as the Tern, but I'm hoping I can swap to a 1 piece handlepost later on. The alignment tab on it sucks because it allows the stem 2-3 degrees of side movement. So if I align the handlebars 90 degrees to the wheel and hit a bump or ride awhile the bar might be a few degrees off 90 later. I know there are sources to buy the one piece Dahon handlepost and I'll ask the local Tern dealer to order me one. For now I just angled the stem vertical so the handlepost overlaps as much as possible to add rigidity.

The Mantis has a little 34" wheelbase (Silvertip is 40.5") but it feels stable enough. It does steer very fast, but since I'm already used to the 20" Silvertip, it's not a bad transition. It turns on a dime, it's very easy to ride slow and do a tight U-turn. It's designed to be slower than the Silvertip (55T and 11-28 cassette) since it has a 52T and 12-25 cassette. I guess with 16" tires you don't want to go over 30kmh.

Weights:
I weighed most of the items myself but the frameset is an estimate since I didn't want to remove the cables. The cassette weight is based off the internet.
BB generic sealed cartridge 374
bell dahon 29
cassette sunrace 8sp 12-25T 281
chainring dahon w/back guard 52T 135
chainring bolts dahon steel 19
chainring guard dahon AL 130
crank bolts dahon mantis folding 26
crankarms dahon arms 576
frame with fork and headset 2750
handlepost adjust 727
hub front D neutron 58
lever Avid FR5 each 152
magnets dahon set 57
pedals dahon mantis folding 434
rimtape generic each 12
saddle WTB speed she 356
seatpost D postpump 33.9 757
clamp dahon 33.9 65
skewers dahon f 50
skewers Dahon r 59
tire primo comet 1.35 each 226
tube kenda kd463 16x1.25-1.5 each 73
vbrake Kinetix speedstop, no U, F&R set 353
wheelset F D hub, spokes, rim, nipples 407
wheelset R D Novatec hub, spokes, rim, nipples 790

Other details:
I ditched the kickstand, bell, and reflectors and it weighed 10216g or 22.47lbs. I then added axle skewers and fenders since it rains a lot here. I wrapped some of the frame with paracord so my Master Lock Street Cuffs can hang there but I'll probably drop this method when I find a suitably strong bag. There are no upper rack fittings on the frame.

Packing in Samsonite Oyster.
I was hoping it would be easy to pack, but I'm sure the Mantis is actually wider than the Silvertip folded.
So the Mantis rear derailler still has to come off to fit in the Oyster. For the record if you take the fork and derailler off the Silvertip off it will also fit in this suitcase. So the Mantis only saves me from removing the fork & stem over the Silvertip. I'm sure if I had a more brick like suitcase instead of a pancake shaped Oyster, it might be able to fit easier.

Conclusion: I suppose this is the fastest 16" Dahon since it has such skinny tires and makes no accomodation to have a rack or luggage truss mounted. So far I like it, I'll have to see if the ride comfort holds up and will swap that POS handlepost. I'd rather drop money into the Mantis than the Silvertip since carrying it on trains will be a large part of its purpose. Hopefully as money comes in I can drop 3-4 pounds off it.
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Old 08-25-12, 10:47 AM   #2
ttakata73
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First round of mods

Hey guys, just thought I'd post my mods and further thoughts on the Mantis.
So long as you pay attention where you are going, a 16" tire is fine for city riding.
I even rode into a wide storm drain grate and amazingly did not pop the tire, warp the rim, or do an endo.
I have to be more careful where I roll but I find the comfort is acceptable considering it has 1.35" wide Primo Comets.
I also find the short frame great for going up and down stairs because I can carry it with only one hand.
I grab the top of the frame near the black band, and the bike goes horizontal as I walk in between the handlebars and seatpost.
If I see other people I then hold it vertical by placing the bottom of the saddle on my shoulder.

Anyways, I'm a weight weenie so I started removing and replacing things.
First, there are no hills in Bangkok so I lost the shifter (-136g), derailler (-257g), and top 7 speeds of the cassette (-257g).
I just have the 12t cog on it with spacers (+14g) and added a Surly Singletor (+157g).

The 2 piece handlepost (-727g) was swapped for a 42cm solid post (+640) so there's almost no flex now.
The stock AL handlebar (-221g) was swapped for a FSA KForce carbon (+100g) but I chopped them as narrow as possible so they are now only 465mm wide (-22g).
The Fox barends are comfy but heavy (+141g) so I ditched the stem (-69g) and have generic foam grips (+18g).
The Avid FR5 levers (-152g) were swapped for AEST (+59g).
I wouldn't trust my life to these levers on a downhill bike but a casual folding bike doesn't need to worry about heavy braking.
The stock seatpost/pump (-757g) became a TAT carbon (+266g) and the AL seatpost shim (-34g) swapped to plastic (+11g).
Axle skewers are a combination of ETIK and J&L titanium (+30g) and much lighter than stock (-109g).
Stock pedals (-434g) were swapped with my drilled Wellgo QRD119 set (+289).
Stock 52T chainring (-135g) was too slow so a generic 60T (+143g) was added.
The steel chainring bolts (-19g) were swapped with LDCNC alloy (+8g).
I'm sick of experimenting with crap saddles so I got the Brooks Finesse titanium (+387g) and lost the original WTB (-356).

So in basic trim mode with no accessories or barends, the bike weighs 18.83 pounds/8.86kg.
Fully loaded as shown its at 21.5 lbs.
That extra weight is the lights, reflexite stickers, Ortlieb bag, bottle cage, fenders, pump (Lezyne Carbon Drive M) hidden in seatpost, custom storage in the frame, spare innertube, patch kit, and waterproof bags for the seat and my cell phone.
I made the storage bin by cutting up a plastic presentation folder and using zipties.


I spent over $600 on the above mods, more than the bike actually cost.
I plan on a Rotor BB, Cannondale Hollowgram crank, AEST brakes, ilink cables, and lighter fasteners.
I'll eventually get this bike under 17 pounds but these things are getting really expensive so it might take some time.
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Old 08-25-12, 03:27 PM   #3
MF Monk
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Great post. Thank you.
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Old 09-07-12, 04:07 AM   #4
FoldingLawrence
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This is a great post! I'm very interested in mods that reduce weight or functionality.. The little storage pot is very resourceful. Nice work!
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Old 09-07-12, 05:53 AM   #5
BassNotBass
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Thanks for the great info. I wasn't aware of the Samsonite Oyster... I'll have look into it some more.
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Old 09-08-12, 02:21 AM   #6
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Nice writeup, good idea for marking interior of suitcase as positioning aid.

China domestic market gets some of the cool bikes and best value. Have brought back several from there.
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