Singlespeed & Fixed Gear - 700c v. 27" and pedal strike

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B17
10-22-05, 02:03 PM
I just got home with a Nishiki Olympic 12 frame- $20 for the entire bike minus the rear wheel. The lugwork on the headtube and the headbadge made me want it. But the wheel that came with the bike is a 27". If I choose to fix this bike, can I expect any pedal strike issues from the BB being 4mm closer to the ground? I know it sounds like a small distance, but it's an honest concern, so I'm asking. Thanks.

baxtefer
10-22-05, 02:59 PM
counteract the 4mm drop by going with 5mm shorter cranks.
Jaminsky
10-22-05, 03:57 PM
Isn't it more like a 7mm drop? But I wouldn't expect it would actually be a problem, even with the cranks you have now.

baxtefer
10-22-05, 04:18 PM
well, the drop depends on the tires you pick, but really you're dealing with a 630mm bead seat diameter on the 27's and a 622mm diameter on the 700's.

so the drop will be around 4mm
B17
10-22-05, 05:11 PM
Thanks for the replies. This frame has long stays (made a bit longer by the use of 700c wheels and tires), and uses those old-style Weinmann center-pull brakes, so I'm not looking to make it look like a racer. It'll likely have 32 or 35mm tires, fenders and my username atop the seatpost.

Crankset will be 165mm. I figure 32 or 35mm on the tires is enough to offset any distance I lose not going any shorter than that on the crankarms.
BostonFixed
10-22-05, 05:22 PM
With 32+mm tires, you won't have any issues with pedal strike. Run whatever length crank you have on there now.
poopncow
10-22-05, 05:39 PM
just a though, if you are going to run brakes....do you have enough reach with the brakes? When I converted my (possibly same era) nishiki from 27 to 700, it was hard to find brakes and the weiman center pulls did not reach the rims. I ended up installing a 700 fork and making up my own "drop" installation for the rear.
poopncow
10-22-05, 05:40 PM
btw; have not grounded with 165's ....but just waiting for the day
treechunk
10-23-05, 05:53 PM
just a though, if you are going to run brakes....do you have enough reach with the brakes? When I converted my (possibly same era) nishiki from 27 to 700, it was hard to find brakes and the weiman center pulls did not reach the rims. I ended up installing a 700 fork and making up my own "drop" installation for the rear.


those old Weinmann brakes come in multiple lengths. I've seen some REALLY long ones. Personally, short of the Paul "new racer" brakes, I think they're the best option for converting a bike to 700 from 27". They stop SO much better than side-pulls of equivalent length.
muccapazza
10-23-05, 08:34 PM
those old Weinmann brakes come in multiple lengths. I've seen some REALLY long ones. Personally, short of the Paul "new racer" brakes, I think they're the best option for converting a bike to 700 from 27". They stop SO much better than side-pulls of equivalent length.

Good idea. Mafac Racers have a pretty long reach, too.
pdxbikelover
10-25-05, 11:16 PM
can u weld on center pul braz ons to old frames
treechunk
10-26-05, 08:23 AM
can u weld on center pul braz ons to old frames


you mean cantilever? http://sheldonbrown.com/gloss_ca-g.html#cantilever

Center-pull brakes are slightly different. http://sheldonbrown.com/gloss_ca-g.html#center-pull



If you mean cantilever, you certainly CAN, but it's not necessarily easy to get them lined up straight if you don't know what you're doing. I've seen a set or two that were added on to an older bike that were off at weird angles and basically left the frame not-so-useable.