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A few questions (track frames / NJS)
1. I've heard generally it's better to size down a little bit for a track frame compared to what you would ride for a road frame. True?
2. Also, about NJS approved frames... I'm assuming in order that no one gets any real advantage over anyone else, all NJS frames, whether they're Samson, Bridgestone or 3Rensho are fairly the same in stiffness, weight, tubing etc.? True? Please excuse my ignorance. Thanks |
The rumor you hear about sizing is due to the bb height. I say they only ride a smaller track frame so they have better clearence to touch in the street, but if you're riding on a track, you aren't going to be standing over your top tube all day. 54cm is 54cm.
PS- size it for the top tube. |
bump it to the top./
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NJS frames seem to vary a bit, I feel.. there are tubing differences, some bikes are fully chromed under paint, some have aero tubes I believe... There are differences, but I'm not sure exactly what standards a bike has to meet to get the stamp. I'm sure someone with more knowledge will chime in soon enough.
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as i understand, bikes are not approved as njs, builders are. the builder submits a frame to be scruitinized/tested for quality/strength to the point they literally destroy it. if they pass, they get to use the stamp. im sure theres some money involved in there, somewhere. sashae? ceya?
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Well, I think there's more to it than just builder, because I'm pretty sure that not every bike (besides the obvious ones with drilled forks) from Kalavinka carry the stamp...
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maybe they have to pay a fee for every time they use the stamp, so they only stamp the ones that are actually goint to be used for keirin? im venturing into hypothesis land, here, so dont take my words as fact.
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Originally Posted by andre nickatina
2. Also, about NJS approved frames... I'm assuming in order that no one gets any real advantage over anyone else, all NJS frames, whether they're Samson, Bridgestone or 3Rensho are fairly the same in stiffness, weight, tubing etc.? True?
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Well, the EAI Gan Well Pros and Nagasawas are made specifically to be exported and sold to non-Keirin riders have the NJS stamp.
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andre nickatina
1. I've heard generally it's better to size down a little bit for a track frame compared to what you would ride for a road frame. True? This is what most was taught prior to 1990s . I follow it today. the rule was if you rode 57c/t seat tube on the road you will go 56 c/t seat tube on track. I find it works well but with compact frames and tig welded frames that rule may not or does not work. 2. Also, about NJS approved frames... I'm assuming in order that no one gets any real advantage over anyone else, all NJS frames, whether they're Samson, Bridgestone or 3Rensho are fairly the same in stiffness, weight, tubing etc.? True? Yes the builder is certified to have NJS stamped on his frame after testing by the Keirin cycling body. Steel frames, lugged are there. remember the thickness and tubing will vary but everything must be certified NJS for thr racer to race it. All Keirin NJS frames that are raced are custom build by the builder. That is why you may see 53 x 56 sizes out there. The bike will be inspected( I think Tomity said 3 days from racing day). It is some what like NASCAR. 3. Please excuse my ignorance. No, its not asking is what causes ignorance Maybe Tomity can fill in more. I will find my Keirin book and look for more info. S/F, CEYA! |
Thank you, Ceya.
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Originally Posted by ryand
The rumor you hear about sizing is due to the bb height.
as far as tube sizes goes, keirin frames have two varieties, regular and oversized, regular: 25.4 TT and 28.6 DT & oversized: 28.6 TT and 31.8 DT. |
[QUOTE=el twe]Well, the EAI Gan Well Pros and Nagasawas are made specifically to be exported and sold to non-Keirin riders have the NJS stamp.[Quote]
Yes alot of custom builders sell to non Keirin racers too. It just telling you the quality of the frame. I got a full Keirin bike in Japan by RAP and another on the way with no Stamp at all by RAP. Panasonic sells a NJS bike in their catalog. S/F, CEYA! |
Originally Posted by Ceya
Yes alot of custom builders sell to non Keirin racers too. It just telling you the quality of the frame. I got a full Keirin bike in Japan by RAP and another on the way with no Stamp at all by RAP.
Panasonic sells a NJS bike in their catalog. S/F, CEYA! |
Originally Posted by el twe
Yeah, I was just throwing that in with the question of whether a builder or an individual frame is given the NJS stamp.
No problem , just supporting your claim. And Thank you for understanding my jiberish replies ( See batty awards). S/F, CEYA! |
http://www.oldskooltrack.com/files/t...rin.frame.html
Tomity explaining on Old Skool track.com S/F, CEYA! |
Originally Posted by el twe
Well, the EAI Gan Well Pros and Nagasawas are made specifically to be exported and sold to non-Keirin riders have the NJS stamp.
The last of the Nagasawa frames made for EAI that was at the EAI facility is a 57cm I believe. I am not sure if American Cyclery and BusinessCycles have "available stock" on the Nagasawas. Both these runs of the Gan Well and Nagasawa frames were made ONLY for EAI (The Gan Well seat stay plugs were custom cut at the factory with "Euro Asia"). The story behind EAI and getting these frames made is pretty interesting. Mr Nagasawa was not accustomed to building "stock" frame sizes - this builder is truly a master and looks at rider measurements, riding style, velodrome dimension and specs - it is incredible how much data he absorbs and injects into each frame. He even treats tubes differently based on the season. Intriguing to say the least. |
Thanks for all the replies. I'll cut to the chase, I'm pretty close to buying a Bridgestone frame (Grand Velo) that's pretty close in measurement to my road conversion (Raleigh). If anyone has anything to say about Bridgestone frames that'd be cool. Basically what I'm looking for is authentic, steep track geometry, something decently light, a higher BB (current one is a bit low though manageable), and smaller tire-to-frame clearance so I can lock it up more places (frame and wheel, with a mini Kryptonite).
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Buy it, Grand Velo by Bridgestone is no longer made and was done in the 70s to about early 80s.
S/F, CEYA! |
I ride a Bridgestone Keirin and I adore it. It's definitely the
best bike I've ever rode. If the Grand Velo fits you, then get it. You will not regret it. |
Originally Posted by Ceya
http://www.oldskooltrack.com/files/t...rin.frame.html
Tomity explaining on Old Skool track.com S/F, CEYA! Very cool. |
does anyone know what the general seatpost size to a bridgestone is. i've tried asking the seller but has not replied and i think i read 26.8 somewhere, but i just want to make sure
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mine's 27.2
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ohh god, i hope mine is 27.2, ohh god i need to know. damn this seller and his vacation
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27.2, 27.0, 26.8.
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