28" / 29'er comparison wanted...

I tried a search but couldn’t find anything comparing 28" to 29’ers. If this has been discussed, please post a link to the thread.

Could someone please tell me how a 28" compares to a 29" wheel, mainly in terms of speed? I’m also interested in hill climbing ability, long distance average speed, and acceleration.

I found a 28" wheel in a bin at a construction site in my street. The hub’s not fixable, but the rim’s fine apart from the odd light rust. It doesn’t have a tyre on there, but I’d like top make use of the rim. It’s only a single-wall rim, but it’s free.

Thanks,
Andrew

I think apart from the availability of tyres, the difference between 28 inch, 29 inch and 700c 9and the old 27 inch) is negligible.

A 20 inch wheel is “only” 4 inches bigger than a 16, but it’s 25% bigger and therefore 25% faster.

A 24 is “only” 4 inches bigger than a 20, but it’s 20% bigger and 20 % faster.

A 28 is only 4 inches bigger than a 24, but it’s 16.7% bigger, and 16.7% faster.

The point being that as wheels get bigger, a small change in diameter makes less difference.

29 inches is 3.6% bigger than 28 inches.

On a direct comparison, identical cranks and so on, a true 29 will be about 3.6% faster than a true 28.

Assuming a cruising speed of 10mph on the 28, the same rider would do 10.35 mph on a 29.

The 29 inch wheel is an inch bigger in diameter, meaning 1/2 inch bigger in radius, so the hub and seat will only be 1/2 inch further off the ground. Freemounting will be virtually unaffected. Steering will be marginally slower on the 29.

So I’d say the biggest factor in choosing between a 28, 700c or 29 is the availability of tyres in the tread pattern and section that you prefer.

As I’m always saying, a 28" wheel in almost all cases is exactly the same wheel as a 29" one. So there’s no difference.

The size used is called 700c. If the wheel you’ve found isn’t 700c sized (put a road racing/hybrid tyre marked 700c or 622-23 or 622-anything else on to check) then bin the rim, the difference in tyre choice and tyre cost will mean it isn’t worth having a non-standard wheel. There are about 3 tyres available for the non standard sizes and they’re all rubbish cheap road tyres.

If your rim is funny, bear in mind that the cost of a decent 700c rim is not very much at all compared with the cost of the frame to put it in, a unicycle hub, spokes etc. although if you work at a bike shop you probably get free spokes, so maybe thats less important. Rims are cheap.

Are you thinking an ultimate wheel from parts of a dead unicycle, or do you have a spare frame that will fit the wheel? Or are you going to put it in the giraffe (now that would be cool). If you’re buying a new frame, try and get one with clearance for the big 29er tyres because you will want one sooner or later (Nimbus2 / Yuni frames do, Nimbus 1 frames don’t).

The difference between 28" and 29" is the tyre you put on it. A normal 28"/700c road tyre is okay for road riding, but pretty harsh and useless offroad, a 29"(still 700c) mtb tyre or a fat (50mm+) slick tyre makes for a much more fun ride.

I’m significantly faster on my 29" tyre than a 28" tyre on anything other than perfectly flat road simply because I fall off less, so I can ride it faster. On perfectly flat newly laid road there isn’t much difference at all, the narrower tyre doesn’t seem to go faster. Hill climbing, the 28" is slightly better at than the 29 because of the lighter weight, but it’s rubbish if the road is bumpy. Acceleration wise, I’d be surprised if you can tell the difference to be honest.

Joe

Thanks a lot guys, that’ll do nicely. I’d completely forgotten that the wheel won’t fit in my 20" frame! I’ll try to find a cheap, bigger frame through the bike shop.

Andrew