Ben Pearre

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HP Velotechnik Speed Machine

I had a chance to borrow a friend’s brand new Speed Machine in the autumn of 2006. I put something like a hundred miles on it over a couple of weeks. My general impression is that HP got a lot of things right, and made a few very, um, odd decisions. The bike is not as performance-oriented as its name would suggest, but it is not a bad bike. On the contrary, despite finding fault with a few things, I really enjoyed the time I spent on it. Of course, I really enjoyed getting back on my own bike afterwards :)

Dave’s bike is outfitted with:

If you want to know where I’m coming from, you should first read my main bike page. That will tell you a little about my regular ride and about what I’m looking for. Yes, I like fast, responsive bikes, and I hoped that the Speed Machine would be such.

The first thing that strikes me about the bike is that it’s, well, ponderous. It weighs about 3kg more than Trebuchet (that’s roughly 3% more weight (including the motor (me))), but it feels like a great deal more. Part of this may be due to the Rotor cranks not being fully broken in yet? Or the chain tubes? Or the poor seat position (more below)? Or perhaps there’s a nonlinear relation between bike weight and perceived weight (which might allow the weight weenies to come closer to justifying spending $30 on a titanium skewer???)…

Underseat steering

HP’s underseat steering is odd. There is a long (15cm?) boom from the USS pivot axis to the handlebars, and I see no reason for this: the handlebars are high enough that tipping them forward or aft can position them anywhere you like (additionally, positioning them too far from the axis of rotation will lead to awkward tillering and a corresponding lack of manoeuverability, but the pivot is about ideally positioned anyway). The long boom requires a correspondingly longer handlebar to reach back to where the hands are (closer to where the pivot was). In other words, HP has a bunch of extra material running in circles. Longer, curvier members mean that the materials need to be heavier. I’m confused.

The next oddity is that the USS is very wide. On Trebuchet (left) my hands are tight to my thighs, almost touching them, and are close to horizontal. On the Speed Machine (right) my arms hang down and are splayed wide, like a drunken Italian grandfather welcoming an acquaintance. Like many grandfathers, this is not adjustable. The profile shots of Trebuchet and Speed Machine do not make the difference in feel of the arm positions obvious, and it may bother you less than it bothered me.

The pivot appears to be very solid. In a spill, a USS handlebar will protect you from the road, taking the impact of bike and rider on the handlebar and steering bushings. I didn’t dump the bike, but HP appears to have done a good job of making this system able to withstand the vagaries of cornering too fast on slippery pavement :)

HP claims that their USS weighs more than ASS. This turns out not to be the case, even with all that extra pipe. Odd. In a good way.

The Seat
HP’s BodyLink seat and AirFlow cushion are interesting. The seat is adjustable and generally comfortable, and certainly stiff.

My major complaint against the seat is, of course, that it won’t go quite where I want it to. It will recline to 25° (I’d prefer lower, but this is not bad), but the front piece simply will not hold my bottom in place! As I pedalled I was constantly pushing myself back in the seat with my legs, making it hard to maintain a round stroke. See the photo of the SpeedMachine seat (left) and that of Trebuchet (right). The seat desperately needs a deeper, um, ass-hole.

Note that Dave, the owner of the bike, does not hate the seat nearly as much as I do. The above issue gives him a little bit of trouble, but he finds it far less awkward than I do. Yes, it was correctly adjusted for me.

The cushion is velcroed on and easily removable (especially nice if your bike is locked up outside a café when a rain shower pulls through). Ventilation is marginal: not nearly as good as a Challenge seat with reticular foam, and not even as good as Trebuchet’s seat (solid with 10 1.5″ holes drilled in it, reticular foam over top).

Dave and I removed the top piece of the two-part seat and weighed it. It’s something like 1.5kg without the pad! The whole seat is probably 3kg, meaning that HP could drop the weight of the bike by over 2kg simply with an upgrade to, say, a Velokraft seat. Of course, DIY will void your warranty. Thanks, HP.

Rear rack
The rack is superb. A small quibble is that it’s too low and too wide—ideally panniers would sit in the rider’s wind shadow. Not sure how much effect this has, really, since without a fairing the turbulent area will expand conelike behind the rider. But other than that, it’s a really nice rack. My wonderful Ortlieb panniers are as secure as ever and very easy on/off. And the rack has a mounting point for a taillight (essential and oft-neglected) and even a step for a flagpole!
Water bottle holders
The HP ones are silly: even 0.5l bottles tend to fall out, and 0.75l bottles are much worse. And no wonder: the bottles are supported near the base, with their weight pulling open the flexible side of the bottle cage. I wonder whether it says something about HP that they sell these things…
Suspension
The rear suspension is quite good. Contrary to HP’s marketing claims, there is some pogoing while pedalling up steep hills. Of course there is! The chain pull geometry is incorrect for eliminating pogoing. But there isn’t much, most of the time. Bumps are absorbed nicely and the wheel stays in touch with the road. I had to set the suspension up pretty tight to avoid a nasty bounce over low-frequency bumps, but it can be done, and once dialed in it kept me happy. Torsionally it is very stiff. They seem to have gotten this part right.

The front suspension is another story. It is an in-headtube design similar in conception to Cannondale’s HeadShok. However, where Cannondale uses a coil or air spring and an oil damper and sets the whole thing in bearings, HP uses an elastomer for spring and damping, the latter being achieved by friction between the elastomer and the walls of the tube. Not to knock HP or anything, but this is what I’d expect on a Huffy (ie. Wal-Mart grade). Since damping is achieved via friction, stiction is horrible.

On the road, the front shock felt OK (and of course rear suspension is much more important for comfort anyway). Sure, you feel bumps more on the front than on the rear, and in gentle braking on smooth roads there’s a bit of a stutter when the shock suddenly gets loaded enough to begin compressing, but unless you’re paying attention these details get lost in the beauty of a smooth ride.

However, as I have noted in the past, the main motivation for a front shock on a recumbent is not comfort but safety. Keeping the front wheel in contact with the pavement is very important: when these bikes start to go over, they go over fast! Of course I did not have an opportuninty to test this shock vs. another on the same bike but I would worry that the Wal-Mart-grade suspension is only used in cheap pieces of crap (and the SpeedMachine) because, maybe, the performance loss is significant. Sensitivity and rebound-rate measurements could easily prove me wrong—or right. Does anyone have data?

Brakes
Some of this may have been due to poor setup (the Denver HP dealer who put the bike together made many grievous mistakes), but on one of the first times Dave and I were out for a ride, he noticed increasing wobble in the front wheel when braking. It turns out that the wheel was actually being ejected from the fork.

This is a known problem of most front disc setups (see Disk brakes and quick releases - what you need to know). The geometry is dangerous, and substantial lawyer lips on the front dropouts are a stupid kludge. I asked HP about this, and rather than refuting the argument on the grounds of physics or geometry, or even dropout lips, they sent me these comforting words:

We are confident about the safety of our front fork.

No evidence, just faith-based marketing. “Despite reason and experience, please trust us.” Great.

When braking hard (or even not very hard) using the front brake, the bike felt wobbly, but I failed to figure this one out. It feels as it would if the fork were wiggly and loose, but every other test I can do indicates that it’s superbly rigid (although it did loosen later and needed to be tightened; I haven’t ridden the bike since. UPDATE: Nope, it still feels very twitchy when braking).

One possible explanation is that the steering geometry is not set up in the way I’m used to. Unlike most bikes, you cannot walk along next to your bike while holding onto the seat—you must hold on to the steering system too, since leaning the bike has no effect on its course. By the way, with USS this sucks. But more to the point, could it also be an indication that the wheel needs some trail?

Chain routing
This is pretty good. I’m a little wary of chain tubes, having ridden a few bikes whose tubes thought they were wandering minstrels. HP uses a good material and ties it down well. The tubes are nigh inaudible, and they stay put. I would love to know how much drag the tubes add…

Dave pointed out that chain tubes can allow a manufacturer to get sloppy about chain routing. On the Speed Machine, the business side of the chain is routed quite well, but the return path isn’t quite perfect, and no-one seems to have numbers to know how much you should care. Compare the nice, straight chain lines on Trebuchet with the lines on the Speed Machine. I have drawn a straight line in green for reference.

The one problem I had was that the return tube can bump the front fork when the latter compresses, forcing the tube to move laterally and suddenly causing the chain coming off either of the smaller chainrings to rattle against the next size up. But I was able to raise the mountpoint, leading maybe to a tiny bit more friction but silent running. Still, don’t they test for these things? Argh!

Update: After a few more hundreds of miles, the chain tube mount broke, causing the chain tube to feed itself to the chainrings. Dave has not yet repaired this. More evidence that HP got lazy about seemingly minor aspects of their design?

Rolldown test
There is a nice 70-vertical-meter 1.3km stretch of road outside my house. We did a brief and vastly unscientific rolldown test. Dave's Speed Machine's Velocity Thracian wheels and 1.35″ Schwalbe Marathon Slicks at 95psi are surely more slippery than my own bargain-bin (32 spokes in back, 36 in front!) wheels and fat (1.5″, 1.75″) tires at 50psi (Waaaaah, I want suspension). And the HP with Dave on board is nearly 10% heavier than Trebuchet with me riding, but the Speed Machine did pull ahead at speeds over about 25km/h. More testing is required, but at least it can be said that this bike is not an airbrake.
Conclusions
I love the suspension. The ride is smooth, and with all that weight comes a very solid bike. Riding it is in some ways reminiscent of driving an SUV: I feel disconnected from the pavement, which is sad on perfectly smooth roads but a godsend on anything rough. Stopping and starting, there is suspension dive, and an SUV-like feeling of wasting energy. The seating position is not tight, adding to the feeling of SUVness. And with the, um, solid build comes the impression that there is really very little that would bother this bike: dirt roads, potholes, even curbs seem like they will be crushed beneath the German behemoth, and indeed, the suspension makes short work of them.

This is not my dream bike. I prefer a ride more like a Ferrari (hence the Wishbone), and this certainly isn’t it. But the engineering is good (vastly better than the Wishbone) and the build quality is excellent. The ride is smooth, the geometry isn’t bad, and despite the flaws I would probably drop the $3500 and void the warranty for a better seat if the bike just didn’t feel so ponderous (and if the company inspired more confidence that they’d tested everything)! HP has the makings of a real winner here. They just need to realise that they’re not done yet.