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thirdgenbird
05-04-2014, 08:45 PM
I pulled out my old 1989 Yokota frame (dad was original owner) for a new build a few weeks ago and when I took out the seatpost I noticed that the seat lug and seat tube are not 100% connected in one area. Externally, there is absolutely no sign of separation or paint cracking.

Here is my armature assessment: the bike was not brazed properly when new. It had been like that for years and thousands of miles and I shouldn't worry. The seatpost and bolt can't hurt either.

Cell phone pics...

You can see/feel it right by the ear:
http://i280.photobucket.com/albums/kk177/thirdgenbird/Yokota-%20ss/6e95247d8e538b490de7a0aff43336d9_zps21729f09.jpg

The other parts of the tube, you can see a joint but it doesn't seem separated:
http://i280.photobucket.com/albums/kk177/thirdgenbird/Yokota-%20ss/94bdd939c78c562d9a5b095e2f1536b0_zpsd80cf687.jpg
pbarry
05-04-2014, 09:00 PM
You shouldn't worry. There's some brass visible at the top of the tube, and you've proven it"s road worthy. :)
ultraman6970
05-04-2014, 09:04 PM
This is the thing, they cut the tube and then they put the lug and then they braze from the outside in. If you have some separation IMO is not a problem the guy that brazed it wasn't that good with the details tho, it wont crack maybe ever anyways.

If the guy goes too heavy in the bronze, it will spill inside, then they need to ream that seat tube way too much. Since those arent bikes that are going to be in a museum, would not surprise me that they did just what was needed to get the frame off the production line quick.Then sure you will find stuff here and there.

Did you check if the seat tube and the down tube are seamed?? Probably are.
alioup
05-04-2014, 09:13 PM
You basically have a non-integrated seat clamp now. It's fine.
thirdgenbird
05-04-2014, 09:28 PM
Yes, the tubing is seemed, double butted tange 1000.

Its nothing special amd the headset is worth more than the frame, but it's too cool, has too many memories, and fits too big of a tire to part with it :)

Thanks all. I was planning to ride it as is, but it's nice hearing confirmation.