"Fast" bike options

[UpWrong]

I’m talking myself into selling my AZUB trike to provide the funds and the space for a “fast” bike. I’ve learnt a thing or two from the bikes I’ve had about my limitations and what suits and what doesn’t suit. Tiller steering is a no-no and being below average height the seat height and BB height/tyre clearance are considerations. Also the seat angle probably needs to be 35 degrees or more but seat shape etc is a factor and manufacturers measure the angle differently. I’ve boiled it down to: Carbon Basso (Giro Spec, B3 seat), Lightning P-38, Metabike Mystique or maybe an HPV Speedmachine.

So this is for day rides/BHPC racing so would run without mudguards. To be fast, the factors are: anatomical/physiological fit for max power output, efficient transmission, aerodynamics, rolling resistance. The first is the hardest to measure and probably the most important. The reason my Stratus XP is to date my fastest ‘bent is because it scores highly on the first two. So far ‘bents with approx equal seat and BB heights have not scored well on the fit/power measure. The Mystique and Speedmachine have 10” and 9” differences in BB/seat heights so would be a new departure for me. BB height on the Mystique is 33”, 27” on the Speedmachine.

The P-38 has a legendary reputation although the closed angle is a bit of a marmite thing apparently. There is a mid-racer conversion to address that but it alters the weight distribution. Also I am between the medium and large sizes but would go with the large size because it has a 20” front wheel cf a 16” wheel on the medium. With short cranks the large size will probably be ok. The P-38 doesn’t score highly for aerodynamics and I might want to change the bars to tweener/aerobars.

I had a Giro 20 in a 30lb build with a Recurve seat and I was slow on it. The BB height on the Mystique could well be a problem. The recline on the Speedmachine might be a problem and more than one owner have said the name is a contradiction. Hence I am leaning towards purchasing a P-38 frameset. I feel I have to experience the legendary P-38!

[belgiangoth]

My SPM is tiller steering, which is fine for me (I believe it provides an aero advantage). It is in NO WAY light, it's basically a lower version of the Streetmachine. Being full suspension I wouldn't call it a racer, it's more of a faster tourer (I'm not convinced I would call it an Audax machine).
Dependent on COVID rules and geographical location you are welcome to take it out for a spin.

P-38 is indeed legendary. The issue with them being that you would have to buy new and unseen from the US.

My thinking on fast bikes are either something higher like a Metabike, or something lower like a Fujin or Furai. The latter two are hard to find, never second hand, and apparently the frame doesn't last. The Metabike Daemon is too new to be available second hand.

[UpWrong]

I had a Metabikes MetaPhysics in 20/26 configuration, with the tiller steering. The custom 20" fork was limited to 28mm tyres. When I put another 20" fork on it with a standard offfset I got some alarming shimmy. It was a very rigid bike with a short wheelbase. The effect when traversing troughs and sunken drain covers was terrifying. I literally got catapulted out of the seat one occassion. Fortunately the car behind stoppped in time. If I had it now I'd try a 24/24 set up with different bars. Hmmm, that might be seller's regret.

[Stradageek]

I had a chat with a couple of Swiss P38 owners at the last UK based world HPV championships. They confirmed that the bike's reputation as a good hill climber is deserved but that it has poor general aerodynamics so it wouldn't be considered fast on the flat.

I use my SPM (tiller steering, often held in hamster position) as a winter commuter and for long rides where comfort is important. It is marginally faster than my stripped down Bacchetta Strada when battling a strong headwind on the flat/downhill but the weight and possibly transmission inefficiency count against it on all other types of terrain, especially hilly terrain. Overall, my Strada is much faster.

I haven't tried many other low-racers, so I defer to those who have. Does anyone rate the Raptobike? They seem to be available second hand.

The bike that looked most impressive at the WHPV - until it punctured - was this one

http://www.bentrideronline.com/messageb ... p?t=150383

We can all dream

[yostumpy]

I’m sort of on a similar position. I love my Streetmachine for what it is, a comfy, day long tourer. I’ve since got into BHPC racing, and I am finding the xtra weight and suspension a distinct disadvantage. So something lighter and faster yes! But this new wee timorous beastie would probably not a good commuter/ tourer make. So it would be N+1 in my case. But I’m a chap that likes ‘one thing that can do many ‘ and I feel a faster, racier ‘bent would be one bike too many. The Fuego is supposed to be quite fast I believe , but not especially light. I too would love to try a P38 or a Phantom, and a velomobile. Tailboxes add speed.

[yostumpy]

hillingdon 1 21 014 by mark tilley, on Flickr
Hillingdon by mark tilley, on Flickr

https://www.youtube.com/watch?v=T4gnoU013fQ&t=2s

https://www.youtube.com/watch?v=PirWYdATyO8&t=536s

My efforts last Sunday @ Hillingdon., Someone thought it good fun to put me in the fast race! Twice!

[UpWrong]

It was nice to meet you there. I was in the slow races and was rather disappointed with my average speeds although the circuit was more lumpy than I expected. I'd lowered the seat to get the bike in the car and raced like that thinking it would be more aero. Maybe it affected my power.

[squeaker]

Metabike Mystique (And can I have a go when you've built it, please!) Or maybe a punt on a secondhand Rapto to see how you get on with the high BB (27cm above seat base, the seat incline angle might need work, though).

[UpWrong]

The Mystique would be good on the race track. Not sure how I'd manage with it on the road. I'd wait for the Aluminium version though, the titanium one is somewhat overbuilt I suspect so stiff and not providing much if any weight advantage. Thought I'd go with the narrow fork and have a pair of 26" wheels with 32 mm tyres to help lower things a little.

[Tigerbiten]

I'd lowered the seat to get the bike in the car and raced like that thinking it would be more aero. Maybe it affected my power.

I've got no evidence to back it up but my understanding is ....
The bigger the knee-hip-shoulder angle is then the less you can engage your glutes for power, so you end up more reliant on your quads.
This drops your max sustainable power output as you get more reclined.
It's why new bent riders need a thousand odd miles to build their quads up to match the new cycling position and get their "bent" legs.
It's also why you think/find less reclined bents climb hills quicker, more max sustained power.
So if you alter your position more reclined then this drops your maximum sustainable power output slightly until you rebuild your bent legs to match the new position.
So you need to experiment/decide if the aero advantage of the more recumbent position is more than the sight power loss from being more reclined.

Luck ........

[UpWrong]

Well, my quads are pretty pathetic so I need a riding position that makes good use of my glutes.

[nobrakes]

I kicked off a big thread on BROL about fast recumbents. You might find it interesting.

http://www.bentrideronline.com/messageb ... p?t=155695

I have one of the fastest recumbents available but the truth is that on real world hilly roads it is still slower than a road bike, despite 5 years riding recumbents hard and training on them, and you get clattered relentlessly on less than smooth road surfaces.

For audax etc yes, I think a fast recumbent is perfect, but I realised that when I want to actually race bikes I prefer being on my road bike. It’s an interesting thread, lots of knowledgeable folks chipping in.

[yostumpy]

It was nice to meet you there. I was in the slow races and was rather disappointed with my average speeds although the circuit was more lumpy than I expected. I'd lowered the seat to get the bike in the car and raced like that thinking it would be more aero. Maybe it affected my power.
51183921185_6a78738559_k.jpg

Ah Yes, its you!. Funny I had no idea, but then I wouldn't really, would I? Nice to meet you, I believe we did chat briefly. You seemed to look very comfortable on your bike.
PS, if you think that was lumpy, wait till you come to Gravesend in September!

[OldBloke]

Have a look at the comments by Paul Copeland here: https://www.facebook.com/groups/5194939 ... 299009143/

[UpWrong]

I kicked off a big thread on BROL about fast recumbents. You might find it interesting.

http://www.bentrideronline.com/messageb ... p?t=155695

I have one of the fastest recumbents available but the truth is that on real world hilly roads it is still slower than a road bike, despite 5 years riding recumbents hard and training on them, and you get clattered relentlessly on less than smooth road surfaces.

For audax etc yes, I think a fast recumbent is perfect, but I realised that when I want to actually race bikes I prefer being on my road bike. It’s an interesting thread, lots of knowledgeable folks chipping in.

Interesting thread thanks. I just want to keep up with my mate on his Roberts Audax really, or at least reduce the time he has to wait for me to catch up. If you are trying to match an upright then good climbing is necessary whereas scarily fast descents aren't. That's perhaps where ridng a P-38 might help, minimising differences on ascents.It'a no fun getting beaten up by the roads either. Running decent width tyres helps when you don't have suspension. On my RANS I use a 42mm folding Pasela rear tyre, whereas on the Paseo I have the 32mm version.The modern P-38 willl accomodate 40mm tyres and it has the suspended seat of course.