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Old 02-18-14, 06:52 PM   #1
technical_tim
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Dahon Jetstream P8 as my new commuter

After quite a lot of looking around and considering various options, I chose to get hold of a Jetstream P8 from Holland bike shop.

I have an older Speed P8 as a spare and commute on a similarly aged, second hand, Helios P8. The Helios has been pretty good, but is showing some signs of age and I decided it may be a good time to upgrade to something newer and decommission (pass on) the old bike before anything needs replacing.

The bike is intended mainly for my shortish cycle only commute. A small folding bike was desired, though a compact fold not essential. Nor was performance and/or gear range. So, lots of potential contenders really, including the fairly obvious Bromptons, Birdys, Terns, and a few Dahon models.

The 20" Terns are, unsurprisingly, similar to the Dahons I own. A couple of models offered by Evans Cycles fit the bill pretty well. However, a suspension option and possibility of switching to disc brakes gave the Jetstream some extra appeal. Other options seemed to mean a move away from a pair of bikes with similar(ish) parts.

Based somewhat on what was available where and at what price, I went for the bronze, v-brake equipped Jetstream P8 (photos of the bike as it was supplied).



The model comes with the Kore seatpost (slightly shorter than the more regular 580mm) and a fairly sporty saddle to match. I planned to replace/switch seatposts, and get hold of a post pump (not essential, but should hopefully lessen the trouble of punctures fixed away from home).

V-brakes mean that the front forks and front hub are the more typical Dahon 74mm. The frame does have disc tabs on the rear triangle as well as v-brake bosses. The rear hub is 130mm, drop-outs seemed to measure about 132mm (Speed and Helios both measure 130mm).

The cranks are FSA Tempo, with a 53T chainring.
Derailleur is an SRAM X-7, which fits on a standard derailleur hanger.
The rear cassette is a Shimano HG41
Rear shock is a Suntour EPICON, 150mm eye to eye. Front suspension forks are Dahon/German A elastomer (not adjustable). No lockout front or rear.

The rims are quite nice looking WTB double wall rims, 15mm inner width (marked 15C).
28 spokes at the back, radial on the non-drive side. 20 spokes on the front.

Tyres are Schwalbe Marathon Supreme, but of the wired variety rather than the lighter folding type (I suspect this may also be the case with the Tern bikes, which seemed equipped with supremes).

The bike came with mudguards. The carrier that can be used on 20" Dahon and Tern link bikes can't be directly fitted to the jetstream.

Pedals are wellglo alloy pedals, but, I had switched over to MKS promenades on the old bike, so the MKS pedals did move across.

The handlebars were 580mm, noticeably wider than the 540mm on my other bikes. I chose to get hold of some cheap low rise bars to cut down to 540mm, I would have cut them down a wee bit more, for filtering in traffic, but there isn't spare length after grips, twist shifter and brake levers.

The non-adjustable handlebar post gives a slightly lower position than I had been using, but short legs do mean that the position is pretty comfortable for me.

I had a go at weighing the bike. It seemed to be pretty much 13kg.
Noticeably heavier than my other bikes, even though they both have rear carriers. Even heavier now with the switch to the postpump (718g) and less sporty saddle.

I haven't ridden the bike far yet, so can't report much. Suspension is definitely a relief when it comes to bumps and holes in the road surface.
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File Type: jpg jetstream.jpg (87.1 KB, 61 views)
File Type: jpg jetstream_2.jpg (70.2 KB, 44 views)
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Old 02-18-14, 08:09 PM   #2
Ed in Toronto
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Beautiful bike, congrats on you purchase.
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Old 02-18-14, 08:41 PM   #3
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Great bike. Congrats and enjoy!

Om,
Yan
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Old 02-19-14, 03:43 AM   #4
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I am sure you wont regret going to full suspension, British roads are not getting any smoother. Have fun riding the bike.
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Old 02-24-14, 04:26 AM   #5
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One of the best. Not really a commuter, but a comfortable ride. Enjoy the off road sections if you find any shortcuts!
Devises more recognition.

If you want it to be quicker consider a spare set of wheels with a close cluster block and kojack tyres. Then fit some fat knobbies for off road and you have virtually two bikes. I have done this when I lived in a terrace house and could not store two bikes.
Also can use a fast seat post and a comfortable seat/suspension to this concept.

Last edited by bhkyte; 02-24-14 at 04:35 AM.
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Old 02-24-14, 06:52 AM   #6
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Does it have a "Handbuilt in the EU" decal like snafu21's Vitesse D7? I understand the big boss @ Maxcom (Dahon's manufacturing partner in Bulgaria) rides a Jetstream.
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Old 02-24-14, 06:44 PM   #7
technical_tim
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Quote:
Originally Posted by tcs View Post
Does it have a "Handbuilt in the EU" decal like snafu21's Vitesse D7? I understand the big boss @ Maxcom (Dahon's manufacturing partner in Bulgaria) rides a Jetstream.
Yep. A nice little sticker on the back of the seat tube.

I've made a few trips to work and back now, not a lot of miles so still early impressions. It's more or less as expected, and as it felt the first time I took it out. Not surprising since it does feel pretty much the same as my other two Dahons.

I have the rear suspension fairly hard, currently the case at around 60psi (though I am not at all light weight). There's no obvious feeling of movement from the rear. The front it much more noticeable, and can bob a little bit if I lean forward. Overall, definitely softer over bumps. The somewhat wider tyres, at about 75-80psi, may also have an effect.

I'm not so sure the bike could be considered a mountain bike, but does seems quite suitable for paths and pretty rough ground. I reckon the suspension is pretty good for the combination of small wheels and London streets.

I know the bike is heavier than my others, and it feels quite obvious when it's lifted about, but probably not noticeable on the road (only a few percent difference in total weight). It does feel a little slower, I'd have to guess the heavier and larger diameter (maybe 3%) tyres making me feel like it's harder work. Really hard to say.

Since SRAM cassettes were cheap from CRC, I picked one up with some spares and swapped to the same 11-28 that I was using with the old bike. My commute is nearly flat, and the 28 hardly gets used. The 14 and 12 teeth 6th and 7th do get used quite a bit (my "go" gears for zipping along the flat, though I'd guess at fairly moderate cadence).

Must try some longer trips at some point soon. Maybe a post with further impressions when I've been using the bike for a bit.
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