Hardwood Single Speed

I think it looks nicer too. There are very few good looking bamboo bike home builds from what i've seen. As sustainable as it might be I hate the hemp twine joints that everyone seems to use on the bamboo joints. Looks like a kids design technology project. There are some lovely carbon jointed frames though.

I thought about a bamboo bike myself and did plenty of research before I decided on this one but using hardwood is a hell of a lot more labour intensive as it takes a long time laminating and shaping the frame by hand where as with the bamboo the tubes are already formed for you.

I can understand the sort of workload it would be, I'm halfway through building a guitar and that's using much softer woods. I was putting it off til next year when I finish sixth form to begin building a frame, but i'm glad I did as I think this will be my number one choice if I do!

Yes, the chain was sat there and I really wanted to get the bike built up! The chain does kind of match the central maple layer and I suspect it might not look bad when it loses its initial shine.

Still on the fence about it though.

Didn't know anyone else did it differently!

http://sheldonbrown.com/brakturn.html#bikeculture

I've clocked up about 100 miles on the bike this weekend so here's the first road report. All my observations are compared to my Condor Pista steel frame as both frames have an identical geometry and similar sort of components.

It handles pretty much identically to the Pista frame in cornering and general maneuverability. On the straight it also feels similar. I can't really feel any significant loss in speed compared with the Pista but it is noticeably smoother and more comfortable. I think the internal damping within the wood absorbs general road vibration very well and gives a very smooth ride. It is also by far the quietest bike I've ever ridden. The only noise is an eerie whistling that comes from the spokes in the front wheel over 23mph. Never had that before.

I haven't measured the lateral stiffness yet compared with the Pista frame but it doesn't feel nearly as lively when I get out of the saddle on hills which makes me think it is probably a fair bit more flexible. The frame is a bit heavier (I haven't measured that yet either) but I was riding without a water bottle and that's about the same as the weight difference so I doubt the weight is the reason it feels different. The rear stays do feel quite a bit more laterally flexible than a steel or alu frame so this is probably the reason. If (when) I build another one, I think I'll try filling in the gap between the seat stays all the way down to the wheel to stiffen up the back end. Alternatively making them a bit thicker would do the trick but I don't want it to look too heavy.

One other thing that I'm going to have to get used to is the size of the top tube. At 50mm wide it is a lot bigger than any bike I've ridden before and I tend to rub my knees on it especially when out of the saddle.

I'd like to go to Regents Park and do some back to back laps with the 2 bikes to see how they compare.

Overall, it rides reassuringly similarly to the Pista frame and I'm pretty pleased with how it's turned out.

superb work

^+1

I forgot, I've got a question for you lot. I've got Sugino cranks, Stronglight chainring and a freewheel on the back. Sheldon told me that I needed a 109 bottom bracket so I used a 110 Shimano BB that I already had. It sends the chain line a mile off and I've had to mount the chainring to the inside of the cranks to get it to run straight. I'm measuring 42mm from the center of the rear hub to the centre of the freewheel whereas with the chainring on the outside of the cranks I get more like 52mm at the chainring. I don't know exactly what the model Sugino cranks are, but does the fact that they have shoulders for mounting the chainring on both sides mean that it's a double rather than single?

Runs beautifully but obviously looks slightly wrong as the chainring is on the inside. Doesn't look like theres enough space for a much shorter BB. Any tips other than changing the cranks?

Hi Linc,
Looks to me like it's a Sugino messenger crank (if someone can confirm)
They typically require a 103mm JIS BB for your 42mm chainline.
I think it's the Sugino 75 that requires a 109mm ISO spindle.

Awesome build by the way - thanks for sharing it with us!

I haven't measured the lateral stiffness yet compared with the Pista frame

Just a thought .. You mentioned earlier in the review the internal damping absorbing the road vibration. I wonder if a similar situation is happening as you get out of the saddle .. ie the wood is absorbing the pedal force and then releasing it more gently then the undamped Pista frame? .. the other way I see it is wood is a composite product so in theory you should be able to improve this by specific grain alignment .. easier said then done though I think? I've no wood working skills. But really this project is something else and the end product looks fantastic so I wouldn't care myself! Just enjoy this beautiful bike :)

Sugino messenger cranks need a 103mm BB, but ime you still need to run it on the inside. I don't really know why they're. Called single speed/track. Cranks.

Wow, amazing!

Hats off, i thought it was tricky making a bike out of steel, but metal is so forgiving, fuck it up in wood and you're screwed! Nice work!

I wonder if a similar situation is happening as you get out of the saddle .. ie the wood is absorbing the pedal force and then releasing it more gently then the undamped Pista frame?

That's a really good point. It would explain why it just doesn't feel as lively. Almost worth the sacrifice for the buttery smooth ride in the saddle though. Another thing i've noticed on the same subject is that if you pick up the bike and drop it, it hardly bounces at all and doesn't clatter around like a normal frame would. A bit like one of those magic drawers that you get in fancy kitchens that you cant slam!

.. the other way I see it is wood is a composite product so in theory you should be able to improve this by specific grain alignment .. easier said then done though I think?

All the tubes have the grain aligned along the length of the tube with the grain crossed over at the joints for joint strength. The one thing this isn't very good for is the twisting forces (torsion) that you get in the down tube, especially when you get out of the saddle. Wood is well known (but poorly documented) for being awful at carrying these twisting forces and my original design was a guess at best when working out how much effect this would have on a bike frame.

A much stiffer frame could be made in a similar way to carbon fibre by wrapping a tube with thin wood laminates at +/-45 degrees to each other so they spiral round the tube but it would make jointing much harder and it mght look more like a chinese wicker basket than a bike! Please don't get me thinking about the next one already! I've got a lot of making up time with the other half (+ riding the finished bike) before I'll be allowed another project : )

Great work, very impressed with the results, as an engineer myself I know how much time and attention to detail goes into the design and research, even before you start the manufacturing. Great to see that your project was successful and to see that you have documented it all so well. inspirational stuff.

Beautiful. That's all I've got to say about that. Very well done my man.

Looks great. I found some really interesting pictures of wooden bikes from the late 1800s in some books I was reading, will try to scan the pages in tomorrow at some point.
I presume you know about cold moulded boats and the like? I don't know if it is possible to scale that construction down, but it would be wonderful.

But fuck me, you would need the patience of several saints and a dead person to cold mould an entire frame with splinters of veneer. I suppose you could use the technique to reinforce areas subject to torsional load, like the bottom bracket/down tube junction.

Poor quality phone photo taken during a pi$$ break on lap 2 of Box Hill for our Olympic Road race course ride (only 2 laps of Box Hill though). I was going to make a comment about the bike being back in its natural environment but it would probably have to be in some Brasilian rainforest for that.

I've glued in some threaded inserts so I can now carry 2 water bottles for the long rides. It was very comfortable for a 100+ mile ride and I was only beaten up Box Hill by a friend on a 7kg Canyon full carbon weight weenie. I did weigh it the other day and it comes in at 10kg on the dot. I guess with better components that could easily be reduced by well over a kilo but I've never been massively bothered by weight weenie nonsence. Better legs are all that's needed.

How has this been for the last 6 months? Any photos??

?

Haha. No photo's I'm afraid apart from the one's that I already posted previously http://ligneusbikes.wordpress.com/hardwood-single-speed/photos/
I've probably got 1500 odd miles under the wheels now. I ride it as my only bike now for commuting and weekend rides. The plan is to get as many miles done as possible to see what goes first. Been through a set of brakes and a set of tyres but the frame is holding up fine. Has also been out in rain, snow... the lot over the winter and hasn't had any issues. Even came off on some black ice on a roundabout the other week but fortunately the saddle took the brunt of the impact and the frame was untouched..... my knee on the other hand. The varnish has had a couple of scratches from the bike shed at work but nothing that some sand paper a brush and the pot of varnish can't fix in 5 mins. In fact the gloss finish cleans reallly easily and doesn't hold oil at all.

I've certainly met a lot more people out on the roads since I started riding it. Literally every day someone will ride up and have a chat on my way into work.

So, now onto the more interesting bit..... the next project!

This has been bubbling away for a few months without any action but I'm about to start Mk2. What'll change?

Well for the past few months I've had an engineering student at Oxford University (seriously!) doing a masters thesis in optimising the stiffness/ strength to weight ratio of wooden tubes. This isn't finished yet and has a few months left to go but should be interesting putting some of the theory into action. I've also procured the use of a CNC machine so we can build it faster and to better tolerances.

Aim is to get to as close to 1.5kg as possible for the frame without compromising stiffness. I very crudely tested the stiffness of my current frame against a friends Cervelo S3 and the wooden frame is undoubtably stiffer. It does weigh twice as much though. But that tells me that I could do exactly the same again, thin the tubes to reduce the weight and it would still be stiff enough. And that's before we've applied any of the research that we've done.

Watch this space................