1981 Nishiki International frame geometry?
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1981 Nishiki International frame geometry?
I have a 1981 Nishiki International (dated by @T-Mar method), and am curious of the geometry. Based on the 1981 Nishiki catalog, this was when the International name was applied to a budget light-touring model. Double-butted tubing, though not particularly light. The 25" frame size weighs 7.6 pounds for frame+fork+headset. I have the "Lake Blue" color.
I'd love to find geometry listing for the bike, particularly the tube angles, fork rake and trail (I can measure everything else easily). The catalog that someone posted on Flickr doesn't have geometry. Curious if anyone knows for this bike, or for another touring-focused International in a nearby year. Here are the dimensions that I measured:
* chainstay and wheelbase measured with rear axle positioned by spacer in the horizontal dropout
I'd love to find geometry listing for the bike, particularly the tube angles, fork rake and trail (I can measure everything else easily). The catalog that someone posted on Flickr doesn't have geometry. Curious if anyone knows for this bike, or for another touring-focused International in a nearby year. Here are the dimensions that I measured:
* chainstay and wheelbase measured with rear axle positioned by spacer in the horizontal dropout
Last edited by TallRider; 05-12-18 at 04:21 PM. Reason: add frame measurements
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Since you have the frame, why not just measure it? Even if it was available, company supplied figures for this era would often be for only a single, mid-sized frame and would not necessarily be representative of larger and smaller frames.
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Or put on wheels with same tire size, and buy a digital angle finder (not much more expensive than a protractor).
Thanks for pointing this out - I should have thought of it.
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Measuring from the photo using an app, I get 72º for the seat tube and 73º head tube angle. Perfect for an audax bike with a Brooks saddle.
You should be able to measure the rake yourself, since you have the frame in front of you. If you can get a broomstick or something through the steer tube, measure the offset from the center of that to the center of where the front axle would be. Or carefully align a yardstick to the center of the head tube / steer tube steering axis, and measure from that. Use an online app to calculate the trail.
You should be able to measure the rake yourself, since you have the frame in front of you. If you can get a broomstick or something through the steer tube, measure the offset from the center of that to the center of where the front axle would be. Or carefully align a yardstick to the center of the head tube / steer tube steering axis, and measure from that. Use an online app to calculate the trail.
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If you have a smart phone, there are apps to turn it into a protractor or angle finder.
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Measuring from the photo using an app, I get 72º for the seat tube and 73º head tube angle. Perfect for an audax bike with a Brooks saddle.
You should be able to measure the rake yourself, since you have the frame in front of you. If you can get a broomstick or something through the steer tube, measure the offset from the center of that to the center of where the front axle would be. Or carefully align a yardstick to the center of the head tube / steer tube steering axis, and measure from that. Use an online app to calculate the trail.
If you have a smart phone, there are apps to turn it into a protractor or angle finder.
You should be able to measure the rake yourself, since you have the frame in front of you. If you can get a broomstick or something through the steer tube, measure the offset from the center of that to the center of where the front axle would be. Or carefully align a yardstick to the center of the head tube / steer tube steering axis, and measure from that. Use an online app to calculate the trail.
If you have a smart phone, there are apps to turn it into a protractor or angle finder.
I got 73.0 degrees for the seat angle, and 73.7 degrees for the head angle. A bit more aggressive than I expected, and doesn't fit with the "touring" designation where they classified the bike at the time.
(Note that this is in the large frame size with 61cm top tube, so I'm still not worried about toe overlap)
I'll see about measuring the rake tomorrow.
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In addition to the 73.7 degree head angle, the fork rake is about 6.2 cm. When combined with 33mm tires, this produces a trail figure of 37mm. So fairly low-trail. Maybe the bike is well-suited for a front rack and randonneur handlebar bag.
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I have a hard time believing your tt measurement as I’ve owned numerous 25” nishikis including an ‘81 comp II and 2 ~83_84 international and have handled dozens more and the tt is always 58 +/-1cm
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The top tube is definitely between 60.5 and 61 cm. I also measured an older (around 1973) Nishiki in a local guy's garage, which had a similarly long head tube. Maybe they had some continuity in the International model having a longer head tube.
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Top tube measurement is from the center of the seat-tube to the center of the head tube. Are you measuring the full width of the head and seat tubes in your measurement?
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The longish top tube was why I bought the frame. I wouldn't have bought a 59, and wouldn't have even considered a 58.