Building a true, 700c road uni

I’m about to start a new wheelbuild and was hoping to get some opinions, especially from anyone who has experience with similar wheel builds. Since I don’t use my 29er much, I thought I would build an actual 700c, road-specific wheel, exclusively for street riding, and for climbing in particular. Currently have the standard 47mm freeride rim and the lightest tire I could find that would roll reasonably well on paved roads.

But I thought why not at least experiment, and build a road-specific wheel, and make it as light as possible. After doing some research on the seemingly endless combinations of 700c rims and tires, I came up with this combo.

The Velocity Dyad 700c 36H 24mm wide rim, for rim brakes.
And the Vittoria Randonneur pro. High psi, super fast rolling road tire.

This would be a super light setup, and much lighter than what I have now, but it would also certainly change the feel of my 29er, quite dramatically I would suspect. So my question is, do you think it would it make an equally dramatic difference/improvement for climbing? And again, it would be used solely for paved streets and for doing 3-8 mile continuous climbs with grades up to 19%.

Hey Terry, I assume you’ve seen this thread but maybe you haven’t.

I have a wheel with the Dyad and a 45mm tire; the lightweight wheel does feel very different from the 47mm rim and 2.2"+ tire.

If lightweight is your ultimate goal that is one thing but I think it can be taken too far and come at the expense of ride-ability. A skinny, high PSI tire will have little rolling resistance for sure but you will feel and have to compensate for every road imperfection, which can tire you out more quickly than using a heavier tire that absorbs some of the chatter.

I haven’t ridden a 35mm tire so I don’t know if it is too far to the skinny/hard side of the spectrum but I am happy with the performance of a 45mm tire on the Dyad. Give the 35mm tire a try but if it doesn’t work as well as you hoped you might try going up a bit in size.

Hey Terry, I assume you’ve seen this thread but maybe you haven’t.

I have a wheel with the Dyad and a 45mm tire; the lightweight wheel does feel very different from the 47mm rim and 2.2"+ tire.

If lightweight is your ultimate goal that is one thing but I think it can be taken too far and come at the expense of ride-ability. A skinny, high PSI tire will have little rolling resistance for sure but you will feel and have to compensate for every road imperfection, which can tire you out more quickly than using a heavier tire that absorbs some of the chatter.

I haven’t ridden a 35mm tire on a unicycle so I don’t know if it is too far to the skinny/hard side of the spectrum but I am happy with the performance of a 45mm tire on the Dyad. Give the 35mm tire a try but if it doesn’t work as well as you hoped you might try going up a bit in size.

Thanks David. I was also thinking about going with something a bit wider which would mean more air volume so I wouldn’t have to run it like a hard tire, but still be a fast roller. I can see the benefit of these super skinny rims and tires on the classic 24 track racers, but whether that would translate to a 700c street uni used only for long sustained climbs, is something I’m not sure about.

Like you mentioned, the much lower wheel weight might very well be canceled out by having to work harder at controlling the wheel, and also feeling every little imperfection in the road. Might have to rethink it and find a middle ground compromise.

Mikefule is the guy to ask about this… he’s posted heaps of threads about his “bacon slicer” adventures.

Here’s a good thread for starters:

Cool, thanks.

Terry, if I were you, I wouldn’t go that narrow. I built up a super light 29er/700c wheel that was great to ride around and climb on, but I also built it strong and supple enough that I didn’t have to worry about things like going off curbs.

I used a Velocity Blunt SL rim which is similar to the Dyad but it is 28mm wide instead of 24mm. This didn’t add much for weight but gave slightly more cushion with the tire.

The tire I used was the Big Apple 29x2.0 (700x50mm) but if I were to do it again, I would go a little narrower and lighter with the Schwalbe Marathon Supreme 700x42mm.

I would totally recommend against going with a tire width less than 700x30 or 35mm. I use a 23mm tire on my track racing uni, but I’m never on the unicycle for more than 1600m. That wheel is totally twitchy and I have tried riding it around town and it totally sucks. It accelerates amazingly, but that’s about it. I actually feel like I climb better on a wider tire since the wheel isn’t quite as twitchy and as a result doesn’t weave side-to-side quite as much.

I climbed up mountain passes in China on my super light 29er, and it climbed amazingly. I wouldn’t go with a “road cycling” style tire.

Was that the one with the Velocity Blunt rim and Big apple? I agree that a super narrow setup, while being very light, would also be very “twitchy” as you say, and the only real advantage would be speed, but not so much for climbing as the main onjective. My LBS did mention the Blunt rim, so I will check that out. Thanks Scott!

A 700 X 32-35 mm tire is just great. That’s what I use for my 700 uni. It used to be my standard ride before I got my 36 guni. I keep it pumped up to about 60 psi. It’s light, responsive, and is a fairly robust tire. Now, I only use it for playing bike polo and the occasional parade. In bike polo it routinely endures getting into train wrecks with the other bikes. So far no problems.

Seeing as how you’ve got a diverse stable of unis at your disposal, I’d recommend putting a skinny, like a 32 mm, on it. That way you’d have something pretty different from your other rides. With some long cranks it could make a pretty good hill climber.

Geoff

Building a multipurpose wheel would make more sense, one that could be used for light muni as well as light street. I’d go with a rim like the Velocity P35, it’s a tad wider that the Blunt, stronger, and still less than 600gm, it’ll spread out your tire and make for a nicer ride.

Go with a light gauge spoke, double or triple butted, for sure make it tubeless as this will save a couple hundred grams, for a brake go with v brakes (unless the rim is disc only…) drill out some Moment cranks, use a non adjustable seat post and lengthen the slots for better seat adjustability, fabricate a T bar that is welded in place to skip the heavy brackets and to reduce flex.

700 in stead of 700c

If you want it light, why not go for tubular, and fly up the hills?
Here are some examples (I’m sure you can find even a lighter rim than this):

http://www.chainreactioncycles.com/Models.aspx?ModelID=71073

http://www.chainreactioncycles.com/Models.aspx?ModelID=31773

This would be a uni for speed, obviously not long distances.

Cato

Probably because all tubs apart from CX ones are a lot narrower than the 35mm+ ones being proposed - not that I have experience of narrow tyres on a uni, but issues are outlined above. What’s more you’d have to be mad to use a track tub like you linked to on the road, even on a bike - anything realistic for road use has no weight advantages over a modern high quality clincher tyre and rim unless you go for expensive carbon rims, and I presume that’s not what is being proposed! Personally I’d still recommend some version of the Schwalbe Marathon over the other tyres you’re looking at - check out the weights, as I’m fairly sure the Marathon Racer is lighter than that Vittoria (and very fast rolling).

Someone mentioned me earlier in the thread. My custom road uni is a 700c with a Mavic rim and a 23 mm high pressure road tyre. It is great fun to ride, but harder work for long distance than my standard KH29.

If I made a uni for practical long distance road work I would go for a fat but smooth tyre.

I’m leaning toward something between the ultra skinny wheel setup and the standard 47mm freeride rim and tire I have now. I don’t want something so skinny that I’ll get a hyper “twitchy” ride response, but I also want to reduce rotational weight as much as practicable. Since I want to run a rim brake, the P35 rim is not an option, so the Alex Adventurer looks like good choice for low weight and reasonable width. (Velocity Dyad is another option of similar weight, same width, and also made for rim brake)

As for a tire I like the Kenda “Happy Medium” which is very light at 434g, and just over 1.5" wide. I think this might make a good rim/tire combination for climbing with my 29er, while not being so skinny that the uni would be hard to control, and it would still roll fast and absorb most road imperfections.

(PS: if anyone knows of a 700c rim made for rim brakes in the 30-35mm width range, let me know! :slight_smile: )

Terry, that looks pretty bumpy for a dedicated road tire. Maybe try a Schwalbe Marathon Racer - similar size and weight (lighter if you go 35 width), but probably a lot faster on pavement.

Ha! was just looking at that one, the 38mm folding bead. Definitely looks like a better tire for road riding.

Possible rim, but spoke count is off: Campagnolo presents the New Scirocco™ 35mm

And here are some more, but perhaps a bit too pricy. :astonished:

edit: oops, 35mm is the depth of the aero rim, not width. Still sexy to look at though.

That’s the profile, not width. But yeah, not a good spoke pattern for a uni!

I was just trying to post that but you beat me to it, lol.

But I think a 24mm wide 700c rim, which seems to be on the wider side for a true road rim, should work fine with the Schwalbe marathon racer 38mm tire. This is also a pretty cool looking 40mm wide 700c tire that is also super light and looks like it would roll fast at high psi and absorb bumps well. Kind of a “cross” tire.