The definitive answer about giraffe hubs.

[hopeful]

A preface: I am aware of another thread that deals very closely with this topic (Anyone try a Torker giraffe yet? why so cheap?), but I felt that this research was deserving of its own thread.

I needed a new wheel for my performance giraffe, and I had been debating with myself about whether to order a Level components track hub (bolt-on cogs) and be stuck using their cogs forever, or a new White Industries Track Hubset (which uses a splined cog interface, but still a standard thread-on lockring), or to buy a high-quality standard track hub like a Phil Wood, Miche, Surly, or Campagnolo.

I decided to buy a double-sided fixed/fixed Surly hub based on my past experiences with the company's products and the level of quality for the price. My reasoning was that I could begin by setting up the wheel as a single-chain giraffe and evaluate cog slippage (if any), and then if I had problems, I could always upgrade to a double-chain design because I have the option of adding a second fixed cog and lockring on the other side (and of course upgrade the crank arms to have chainwheels on both sides)

I built the wheel as strong as possible because I didn't want to have another rebuild down the road- Surly New Track Hub, 20" Sun RhynoLite rim, 36 straight-guage DT Swiss spokes with brass nipples, 3X spoke lacing, Velox rim tape, a quality tube, a Maxxis Hookworm tire, a 21 tooth Surly 1/8" track cog, and a Surly stainless steel lockring. I had the cog and lockring installed at my favorite LBS, Salvagetti in Denver (they also ordered all of the parts I needed and were very helpful in finding the correct sizes, materials, and colors of everything).

I trust the mechanics at Salvagetti explicitly for doing things right, I am a professionally trained bicycle mechanic myself (I attended Barnett Bicycle Institute in Colorado Springs, CO) and am very pleased with the level and quality of service at Salvagetti.

I rode my giraffe very hard for about a week, running mounts, forwards riding, backwards riding, idling, hopping, and had no problems until today- I was performing in Washington Park and I felt the cog slip- a familiar sensation from riding track bikes hard enough to break cogs, chains, hubs, and wheels. I immediately stopped riding and verified that the cog was indeed slipping.

Based on the level of attention I put into making sure that everything was right, I cannot blame the components (top-quality) or the labor (done completely by the book), so the only rational conclusion is that the single-chain giraffe with a threaded lockring is not suitable for safe use by persons who enjoy being safe and in one piece a the end of the day.

I am going to tighten up the loose cog and lockring and add a second cog and lockring on the left side of the giraffe along with upgrading my crank arms so I have left-and-right drive chains. I will ride my giraffe as a double-chain version and report back any problems or observations.

[joemarshall]

Hey,

if you look at the newer posh giraffes for sale, they have double sided hubs with bolt on cogs on.

I don't know if unicycle.com can get just a nimbus giraffe wheel on its own, but if they could, that'd probably be a nice thing.

If not, you can build a bolt on hub using a disc hub - there are a few places that sell sprockets that will fit on a disc hub - although whether they come in giraffe suitable sizes I'm not sure, and surly that make fixed / disc hubs so you can run twin chain with bolt on one side / normal on the other.

Joe

[johnfoss]

Hopeful has once again confirmed that screw-on cogs with lockrings are not suitable for giraffe unicycles. They're much better suited to things that only get pedaled in one direction. Always go for a bolt-on cog when you can!

[Rowan]

Once upon a time when a giraffe was my main form of transport (my cranks had snapped off my 24" unicycle, one first then the other), I rode it everywhere, including offroad. I found that I had to watch my head for branches as well as the ground for bumps and roots. Anyway I was going down my friends driveway which was quite steep and it was quite an eerie feeling to have the cog unwind itself from the hub from using too much back pressure. I got a new straight one but these days the giraffe is out of action because the frame bends in the middle so easily, I think from my friends practising freemounts. It would be cool to get one with a sturdy hub and a strong frame.

[hopeful]

I added a second cog, lockring,and left drive crank today along with another chain and I am ready to start testing my giraffe as a dual-chain model. Will post more information as it becomes available.

Matt.

[saskatchewanian]

I am not really into giraffes that much so I don't really know what is out there. Stumbled upon this on the MTBR forums. It is a cog that bolts onto the disk mounts for a MTB hub. Should be perfect for a giraffe in my opinion. There is no way this thing is going to screw off.

tomicog

[hopeful]

It's been a while- 18 days since I added the second cog, lockring, chain, and chainwheel, and it seems pretty solid. I haven't had any slippage while riding, and I've ridden it a fair amount, and even done some running mounts.

Saskatchewanian, Thanks for posting the pics and the link; I am familiar with the Tomi Cogs, but wanted something more readily available for my giraffe, so this is the option that I chose after considering price, availability, and the lack of a definitive answer about thread-on cogs being safe on giraffes based on the quality of componentry and skill of the mechanic installing said componentry.

Perhaps some other ambitious giraffe rider out there has used, is using, or would like to use the Tomi Cog and present us with a definitive answer regarding that particular product here on the forum.

Regards,

Matt.