Project Blue Bike (lowracer commuter bike)

[renault_megane_dci]

Nice project.

What stopped me from further investigation on DIY recumbent is the suspension.
Where I drive, I need to go up and down passageways like 3 inches high and the position provided by a recumbent won't allow driver's easing it out ...

Wouldn't you have the same issue ?

[arcosine]

Can you ride at 45mph with one hand? I hit 48 mph yesterday just before the bridge. This flick is a few years old:

https://www.youtube.com/watch?v=F1nP8LSvymQ

[order99]

Just wondering-from the schematics above it looks like this is going to be a FWD recumbent-and most recumbents with mismatched wheels usually have RWD ging to the large wheel for better top-end speed.

Given the FWD nature of the plan above, why not use a larger fork-wheel diameter and a smaller rear wheel, or two even wheels for a slight rise in height (less Aero, but better traffic visability and balance overall)? any changes to the geometry resulting can always readjusted back with a few small frame bends to correct...

[Sven7]

Originally Posted by Grant-53

The aero drag on an non faired recumbent may be the same as that of a racing tuck upright.

Yes, and who would want to go to work in a racing tuck every day?

Originally Posted by vskid3

Are you sure you'll be able to double your average speed? Even on my ebike with a 28MPH top speed, I only average about 21 or 22MPH with stops included.

I don't know. I assume you're riding on the road? There are only three stop lights and three stop signs on my way to work (and I usually hit one on the walk sign), so even if I'm on the street it shouldn't be bad...

Originally Posted by renault_megane_dci

Nice project.

What stopped me from further investigation on DIY recumbent is the suspension.
Where I drive, I need to go up and down passageways like 3 inches high and the position provided by a recumbent won't allow driver's easing it out ...

Wouldn't you have the same issue ?

Thanks! I don't know what you mean by passageways. We do have some sizeable bumps here though, and that's why I chose wide steel rims with fat (for lowracer standards) tires and hub brakes.

Originally Posted by arcosine

Can you ride at 45mph with one hand?.

No, because I don't have a recumbent yet...

Originally Posted by order99

Just wondering-from the schematics above it looks like this is going to be a FWD recumbent-and most recumbents with mismatched wheels usually have RWD ging to the large wheel for better top-end speed.

Given the FWD nature of the plan above, why not use a larger fork-wheel diameter and a smaller rear wheel, or two even wheels for a slight rise in height (less Aero, but better traffic visability and balance overall)? any changes to the geometry resulting can always readjusted back with a few small frame bends to correct...

If the front wheel were bigger I would have trouble getting my short legs around it. Trust me, i wanted to do a 406/406 or even 406/559 but it just wasn't going to work. The rear wheel can't be too tall either because I want to be able to carry a small bag on top of the cargo rack without it poking too far above my head into the windstream. Hopefully most things will fit in slim panniers in the seat's slipstream.

So, I am going with the huge chainring to the smallest cog I could fit. If the chainring ends up being too small (and even if it doesn't), I may end up getting a new one machined out of plate aluminum with some old school cutouts like this.

[sheepdog 44]

Have you thought of an electric assist bike? I recently rode two different kits that were really inexpensive at only several hundred dollars. Both were in wheel motors and the improvement is massive. Just from two cordless drill batteries at 800 watts, i could fly up hills that would have me at a crawl without assist. Assisting at half the power you pedal will give a range of greater than 20 miles.

[Sven7]

No, that would ruin the fun for me. I like my bikes to be human powered only!

I have a ton of things to do but hopefully will get more of these blueprints worked out! Rebuilding my mountain bike now after a minor crash and taco'd rim, and doing a big drawing for my dad and selling my car and (breathe in, breathe out) yikes.

[Grant-53]

Sven, I use aero bars on my commuter and they are quite comfortable. But this is your thread. See the array of info at recumbents.com and The Bicycleman has reviews.

[renault_megane_dci]

Originally Posted by Sven7

Thanks! I don't know what you mean by passageways. We do have some sizeable bumps here though, and that's why I chose wide steel rims with fat (for lowracer standards) tires and hub brakes.
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Sorry I mean sidewalks border or shoulder maybe ?

Because sometime it is required to leave the road for the sidewalk.

Basically a recumbent can't be soft wheelied over such a border, making for a less fluid ride (with my personnal ride in mind)

[Sven7]

Grant- I have a front rack that prevents aero bars, and don't like my stomach to be folded in half in a tuck. My neck also starts to hurt after looking up for a while. And I kind of just want to build a weird bike.

Renault- Ah yes, we call it a curb. Usually here there is a short ramp from the sidewalk onto the road so it can be traversed somewhat smoothly. The alignment of concrete slabs varies, but if it's really bad I can just choose to ride on the road in most places. I've never ridden a recumbent on the sidewalk, so it will be a learning experience. I'm sure some technique adaptation will be necessary.

Over half my daily commute is on surface roads (riding an upright), so that won't be an area of concern. The other part (a mile) is a 40mph (65kph) four lane road, where I ride the sidewalk when possible since there is rarely foot traffic. Bikes are only technically allowed on 35mph or less in Michigan and I have gotten heckled for riding on these higher speed roads- even in the dead of winter when it just snowed and it's the only passable route.

Moral is, I'll ride wherever I need to ride, and motorists will be angry no matter what.

[Grant-53]

Every bike regardless of design is to be careful matched to the purpose desired and the comfort of the rider. My frame, seat, and handlebars are precisely sized to accommodate my ample girth. You will find the best position to fit you and your muscles will adapt with use. If a rear suspension is not feasible at least put some type of springing under your seat.

If the 65T chain ring is too big for the frame a smaller gear on the hub could let you use a smaller chain ring and get the same ratio. Either 42/13T or 52/16T will be the same ratio and should be readily available.