Friday, January 2, 2015

Tales of the Dahon Jetstream - Part 2

Post-expedition years.. 

The Jeram exploration ride
Spare all the offroad "biggies" that we had indulged ourselves in, we managed to throw in a couple of day-trippers around the Klang Valley, Pahang and Perak.
Since we were no longer considered as members of the "inner-circle" we are pretty much on our own and that is never an issue. 
Living up to it's name, the Jetstream is a versatile folding trail bike that you can pack, stow and transport -- literally to anywhere around the globe.
Although the bike is bulkier than most standard folding bikes, it's made to perform.
Rather than making it compact, Dahon produces the Jetstream with a solid handlebar stem and the EX variant is one of few folding bikes that features a VRO syntace steering system.
Unlike the P8, the EX is more robust and solid when it comes to handling.
But all these came with a price.
It's easier to pack a Dahon Speed P8 and TR onto a regular-sized Dahon Airporter for air transport than with the Jetstream.
In order to fit in the bike, the handlebar stem and wheels had to be dismantled.
Another thing is this: if you noticed the frame geometry, the handlebar stem is shorter than any other folding bikes in Dahon's stable.
The top tube is angled to give it a higher ground clearance as most folding bikes tend to have a lower centre of gravity.
There are no seatpost pumps and to protect the chainring, a guard is placed on the downtube.
To me, the Jetstream is my compact getaway bike and with the full-suspension feature, it can go anywhere at a moment's notice.
In late 2013, we began to explore part of the country by packing the bikes in our car. Most noteable was Taiping where we rode to Port Weld and explored the area.
We also rode to Pantai Jeram from Kapar to look at the trails there.

Port Weld with team Jetstream

Along came the Maxxis tires..

The folded bead before installation
Maxxis DTH on the front fork

Our Schwalbe Marathon Supreme tires that came standard with the Dahon Jetstreams provided comfort and peerless puncture protection.
After wearing out the threads, it was time to get a replacement.
The first thing on my mind were the 20" Schwalbe Mad Mike tires. These are proven dirt tires used by BMX bicycles.
Sadly, they are not available in the country and the people here favours the Schwalbe Big Apple.
Our alternative choice were the Maxxis DTH (Down Throw Hammer). These are tires with foldable beads and offers a certain degree of puncture protection.
What's impressive were the M-shaped threads that are grippy and at the same time, has a lower surface resistance.
We tried these by cycling up the Selangor Dam and found that the road-holding qualities are excellent.

Bling-blings for the Jet

Aye-Ups on the Jetstream EX's cockpit area

We started equipping the bikes with Cateye headlights. 
But these weren't enough to endure the rigors of lengthy night rides on the trail.
To get things going, I have outfitted Michelle's P8 with a Sigma Powerled Pro LED headlight.
These are lights powered by rechargeable Lithium-Ion batteries.
The lights are great, but there is big flaw on it.
After a couple of outings the mounting bracket broke into pieces. There were no spare parts for this particular accessory and what is more disappointing was the fact that the people who bring them into the country could not give a fuck.
I turned to Australia's Aye-Up lights and have no bad things to say about them.
After a few major expeditions, these low-maintenance lights became my primary source of illumination and since they are powered by Li-io cells, the battery life is commendable.

Indonesia: the breaking point..

Riding on a re-surfaced road in Sumatera

Thule's solution to carrying luggage on the Jetsteam EX
The weakest part on the bike: the Ashima PCB brake levers
The Jet, fully loaded..
Riding in the rural setting, Indonesia


I took the Jetstream EX to Indonesia for a 240km ride from Dumai - Pekanbaru.
Due to the unreliable road conditions in Eastern Sumatera, the Jet was my choice pick to ge the job done.
I had the bike fitted with a Thule Pack 'n Pedal rear luggage rack. These proved to be a vital part of the expedition as the entire weight of the bike's luggage was held together by a piece of flimsy aluminium tube and several pieces of plastic.
Even with a lot of spokes, the bike's kinetic pro double-walled rims could not take the brunt of the weight.
One of the spokes snapped. Despite that, the Jet just kept on going and going and going.. 
Having survived the 200km journey, the one thing that I did not expect was the horrific baggage handlers at the Dumai ferry terminal.
These guys had literally destroyed my Ashima PCB brake lever. It snapped when the workers had tried to pry the bagged bikes and the months that ensued became a thing of agony.
I have say that Ashima has a lousy customer service and their distributor in Malaysia is of no help.
That said, the EX was taken off the active duty list as most of the rides were mainly done on the larger Tern Eclipse S18 bike.

Shimano Zee hydraulic brake system and Rockshox Monarch SL: the Jetstream Life Extension Programme (JLEP)

Ready for more action: the retro-fitted Dahon Jetstream EX

Rockshox Monarch SL rear suspension

Absolute braking power: The Shimano Zee brakes

The Ashima PCBs have to go. That is a fact and I have spent months in search of a suitable replacement.
My first choice were the Shimano Saint downhill hydraulic brakes.
These are not available in the country.
Later, I traced a shop that sells the Shimano Zee hydraulic brake system. These are quad-piston hydraulics with ample stopping power.
 But, the brake lines were white in colour. Bummer! That said, after an exhaustive search, I managed to locate a shop in Serdang that sells the Zee in black brake lines. Problem solved. I also found a pair of 160mm, six-bolt Shimano ICE rotors. 
They have to be installed to pair with the Zees as the Ashima PCM Air Rotors are rendered useless. The next step, was to replace the ageing SR Suntour Epicon E rear suspension. These are smaller 165mm shocks that are not easy to find.
My first choice were the Fox suspension, but these are nowhere to be found, especially in the 165mm configuration. But, luck was on my side as I managed to secure a Rockshox Monarch SL suspension. 
I first had the brakes installed and the broken spoke fixed before assembling the Rockshox Monarch SL rear suspension myself.

Was it worth spending so much for upgrading parts? 

Well, look at it this way: I gave the Jetstream EX the best I could get because it's bound for the foothills of the Himalayas and the Mongolian Steppes.
I wasn't going to waste money on cheap components and watch the bike disentigrate over a short period. Simiarly, I am in the process of upgrading the Jetstream P8's components starting with the rear suspension.
Way I see it, there will be more adventures in the horizon and we are aiming for it with our retro-fitted Dahon Jetstreams. It will be an utter waste to keep a good bike as such as a trophy..

2 comments:

jetstream-otaku said...

Hi Sam,

I'm thinking to replace my Jeststream rear shock. As you know 150/152mm are difficult to find.

Did you finally installed a Monarch 165mm or 152mm on your EX?

Thanks for your help

Jean-Philippe
jitensha.jpdn.net

samo said...

Hello Jean-Philippe,

I am using a Monarch-SL 152mm shock on my Jetstream EX's rear suspension.
Did the same by installing the same shock absorbers on my wife's Jetstream P8.
So far, no issues running it on trails and even some hardcore tracks in Malaysia.

Sam