700c wheels on a Giro 26

[Kalgrm]

After cogitating for a few months, I finally got my gear together and built up a set of 700c wheels for my Bacchetta Giro 26.

The wheels: Velocity Deep V rims, 32 hole, black non-machined finish ($200). The hubs are XT disc 32 hole ($110) and the spokes are black DT Swiss double butted (32x280mm & 32x282mm) with alloy nipples ($125). I built the wheels up myself (wheelset total cost: $435)

The tyres: Continental 23c Ultra-Gatorskins with Mr Tuffy liners. Pressure = 110psi

First impressions: LOVE 'EM!!!! I now wish I had done it much earlier. Aside from being significantly faster, the ride is actually smoother than my 26x1.25" slicks (AT) 100psi, most likely due to the larger diameter wheels. The rear hub runs nearly silently, which is a relief after running my Hope XC hubs (my MTB wheels) since getting the bike in April. The silence seems to make the ride "feel" smoother when I'm coasting.

I was expecting to have some minor stability issues with the change in wheel diameter (fork rake and trail, etc.), however that has not eventuated. In fact, if I had to make a call, I'd say the bike feels more stable than before (maybe due to the ~25mm increase in the centre of gravity height?).

I have yet to encounter a steep hill (not many around here) so I don't know how the loss of my lowest gears will pan out. The hills I have hit didn't slow me down as much as I thought they would (due to the reduced rolling resistance.?) I'm hoping that translates well to the steepest hills, and the lowest gears will not be missed too badly.

The raising of the seat has not been a problem when I'm stopped and sitting on the bike. I thought I might feel a little stretched out, but I've been pleasantly surprised.

The Verdict: If you are considering doing this upgrade, don't wait.

Cheers,
Graeme

(Photos to follow later tonight)

[europa]

This is one reason I was disappointed to hear the Flying Hampster didn't have discs - this option was removed from me.

Glad to hear it worked.
The increased diameter would increase your trail slightly and I reckon that's where the extra stability comes from.

Richard

[Kalgrm]

This is one reason I was disappointed to hear the Flying Hampster didn't have discs - this option was removed from me.

You may never have had that option: the clever guys at Bacchetta designed the Giro 26 frame and fork to accept 700c wheels (the "chain stays" were intentionally elongated) even though they released the bike with 26" wheels. I can't remember how much extra space there is between the wheel and the frame on your bike, but if there is room and you can make the brakes work, you may cludge it together (if anybody can, it's you! )

In any case, you always said the Flying Hamster was to be your introduction to 'bents. You can get a Giro 26 when you're old enough .....

Cheers,
Graeme

[europa]

700c wheels will go in there.
Brakes? This bike is steel, if worst comes to worst, I'll get the fittings brazed on (can't do that with ally or cf can you **pokes out tongue**).

But yeah, buying a new bike is a lot more fun than trying to do weirdness to your current one. Mind you, you do see adaptors on ebay that claim to convert a non disc brake frame to one using discs

How about I learn to ride the rotten thing first, then get some strength up, then wear out a few bits, THEN think about disc brakes and big wheels.
Nah, that'd be sensible

Best of luck with the new wheels. Keep us posted on how you find them ... especially if you can find a hill or two.

Richard

[Hotdog]

Great stuff Graeme, I'll definitely be building up a set of 700c wheels myself in the new year. Learning to build and maintain my own bike wheels is one of my cycling new year resolutions, and what better way to learn than to give the Comfy Chair an upgrade?

How much clearance is left in the fork and frame with the big wheels in? I gather that there's enough space to fit tyres up to about 28mm width, does that sound about right? Any chance of squeezing a set of narrow mudguards in there when using 23mm tyres? Not an essential feature from my point of view, but it'd be nice if it was possible.

[Kalgrm]

You're 30 minutes too quick for me!

Here are the photos of those areas you mention. I've just been preparing them to post as your questions came online.





I'd say you can easily fit 28c tyres on the rims. There is a lot of room either side of the tyres, but not much between the outside edge of the rear tyre and the frame (say 5-8mm?)

Cheers,
Graeme

[Hotdog]

Thanks for the photos Graeme, very helpful.

Looks like the limiting factor as far as tyre size goes would be interference with the rear calliper brake mount. On the Bacchetta forums I've heard of people grinding the corner off that in order to squeeze moderate width tyres into the notoriously tight Corsa frames, but as you say there seems to be enough room on the Giro frame for at least 28mm as is.

It even looks like fitting a standard mudguard on the front would be no trouble with 23mm tyres. The brake mount would get in the way at the back if using the official mounting points, but you could probably rig something decent up by using the vacant brake mount as the forward attachment point instead of the braze-on under the tube.

I'll have to give this a go myself soon...