large merlin with a small wheelset -why

[wc1934]

saw this on craigslist - why would you have 650's on such a big bike -just curious -
http://boston.craigslist.org/gbs/bik/2831520420.html

[kramnnim]

Someone on the Slowtwitch forums had a similar Ghisallo for sale a couple years ago...said he got it custom built for the little wheels because he already had several sets of fancy carbon 650's from his other (tri) bikes, and wanted to be able to use them.

[bargainguy]

There is also the remote possibility that if you're running insanely long cranks, you could run into toe overlap with 700c wheels that would be reduced slightly with 650's.

Having said that, I've never heard of this happening in large road bikes, but in really small road bikes, toe overlap is a serious issue with 700's. I'm 5'4 and have a 43cm indy fab with 700c wheels and 170 cranks, and I have to be really careful with this. On my 650c bikes, not really an issue with the same length cranks.

Don

[bobswire]

Saw this today at LBS, Albert Eisentraut fixed gear with 26" wheels and fork with canti's. On consignment $900. :confused:

http://i43.tinypic.com/29pt3t0.jpg

http://i44.tinypic.com/24llr2p.jpg

[djg21]

saw this on craigslist - why would you have 650's on such a big bike -just curious -
http://boston.craigslist.org/gbs/bik/2831520420.html


650c wheels were pushed on Tri bikes briefly in the late 90s. They supposedly offered better aerodynamics than 700c wheels , but the difference was marginal, and became even more insignificant as rim designs evolved.

[bargainguy]

Any small wheel will spin up faster, that's true. But if you take your 700c wheeled bike and put on 650's, you reduce your ultimate top end -- unless you change your gearing to compensate.

Don

[roguedog]

Saw this today at LBS, Albert Eisentraut fixed gear with 26" wheels and fork with canti's. ]

Was that American cyclery? Curious.

[bobswire]

Was that American cyclery? Curious.

Bike Nook on Taraval St. http://www.bikenook.com/cantgettotheshop.html

[ergott]

The Mini Velo is a viable solution to living a car-less lifestyle in our increasingly dense cities. This style of bicycle is already a huge success in Japanese cities, where space is tight. With a length of less than five feet it can fit where most other bicycles can’t. Fun to ride and very manueverable (sp) in traffic.

http://www.somafab.com/wp-content/uploads/2011/05/soma_frame_minivelo.jpg

[Mark McM]

650c wheels were pushed on Tri bikes briefly in the late 90s. They supposedly offered better aerodynamics than 700c wheels , but the difference was marginal, and became even more insignificant as rim designs evolved.

That, plus smaller diameter wheels have more rolling resistance (all else being equal), so it becomes a wash - most of the aero benefits are cancelled by the extra rolling resistance

[ergott]

That, plus smaller diameter wheels have more rolling resistance (all else being equal), so it becomes a wash - most of the aero benefits are cancelled by the extra rolling resistance

You are a marketer's nemesis.
:beer:

[David Kirk]

That, plus smaller diameter wheels have more rolling resistance (all else being equal), so it becomes a wash - most of the aero benefits are cancelled by the extra rolling resistance

I don't think that is really true. Yes the rolling resistance goes up but not at the same rate as the aero resistance falls so you end up with a net gain in most cases. If you were to go super small - say like a roller blade wheel - the rolling resistance goes up so far that the almost complete lack of air resistance doesn't matter.

Alex Moulton put this to the test a long time ago and used bikes with 17" wheels to set a large number of world records before the governing bodies outlawed the smaller wheels.

One often overlooked side benefit to smaller wheels comes when everyone uses them. They allow riders to ride even closer together and get a better draft so speeds go up even more. In this case it helps some to have smaller wheels yourself but it helps even more to have your entire team running them in the TTT.

Fun stuff.

dave

[Polyglot]

Cino Cinelli was a major supporter of the reduction in size of wheels and he built many custom bikes that used a wheel size that fell between 650C and 700C wheel size. (I have two of them in my garage) His explanation was that the 700C wheel size was brought out when roads were still largely unpaved and when rims were not overly resistant. With improved roads and rim materials, there was no need to use such large wheels and that you gain multiple advantages with smaller wheels. The main advantages that interested Cinelli were greater flexibility in frame design and the option of using larger cranks, another idea that he supported. As mentioned, you can run larger cranks which offer better leverage. On one of the Cinelli bikes that I mentioned earlier, a 52 cm frame, it was set up from the beginning to run with 175 mm cranks, all the while maintaining full toe clip clearance. While this is not completely unknown in frames that size, this is not as easy to achieve with 700C wheels.

[John Price]

To Dave's point, I seem to recall that one of the reasons time trial bikes went to smaller front wheels back in the 80s (90s? whenever it was) was so the team time trialists could ride closer together.

[goonster]

That Eisentraut fixie is pretty cool . . .

I'd love to know the story behind that bike, since it obviously predates the current fixie craze, but also doesn't look like an obvious choice for a roadie of that era.