DA-7900 shifters - for down tube...
02-24-16, 12:41 PM
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DA-7900 shifters - for down tube...
So I ordered a set of 7900 DT shifters for a future 10spd upgrade project for one of my 80's bikes. They didn't come with adapters curved to match the down tube, yet in the instructions it shows that it does.
The instructions show a proper curved adapter that mates up to the down tube. But what I got was flat with no curves, and sticks out a bit from the down tube revealing the braze on mount partly and some scratches, etc.
I got it from Gap30cycles via amazon https://www.amazon.com/gp/product/B00...ilpage_o02_s00 and in the pics there it does not show the adapters either, so I am not sure if they really were suppose to include them or not. Has anyone used these before and have they come with the right down tube adapters?
The instructions show a proper curved adapter that mates up to the down tube. But what I got was flat with no curves, and sticks out a bit from the down tube revealing the braze on mount partly and some scratches, etc.
I got it from Gap30cycles via amazon https://www.amazon.com/gp/product/B00...ilpage_o02_s00 and in the pics there it does not show the adapters either, so I am not sure if they really were suppose to include them or not. Has anyone used these before and have they come with the right down tube adapters?
02-24-16, 12:54 PM
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AT one time these backing plates/adapters were as common as most of the DT levered bikes from the early/mid 1980s to the mid 1990s used them. Curved for steel frames and some AL ones and flat for those AL frames with bonded/bolted through lever bosses.
The levers should, IIRC, work Ok with the flat plates. But any shop that has been around for a while and believes in keeping old stuff around for future repairs very likely has some curved ones in a box. Andy.
The levers should, IIRC, work Ok with the flat plates. But any shop that has been around for a while and believes in keeping old stuff around for future repairs very likely has some curved ones in a box. Andy.
02-24-16, 03:05 PM
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The curved base plates were made for use with "standard diameter" (1-1/8") downtubes on older steel frames to match the tube curve. When "oversize" tubing became common in aluminum, Ti and even steel the curved bases didn't match and flat bases became standard issue. As Andrew noted, the flat ones will work fine even with standard diameter tubes.
02-24-16, 03:13 PM
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Shimano Boss Covers for Road Bike Downtube Shifters Bosses Adapter Curved | eBay
That's what you want, though I don't think I could bring myself to pay $21 for them. You should be able to scrounge some up somewhere.
That's what you want, though I don't think I could bring myself to pay $21 for them. You should be able to scrounge some up somewhere.
02-24-16, 03:31 PM
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Shimano Boss Covers for Road Bike Downtube Shifters Bosses Adapter Curved | eBay
That's what you want, though I don't think I could bring myself to pay $21 for them. You should be able to scrounge some up somewhere.
That's what you want, though I don't think I could bring myself to pay $21 for them. You should be able to scrounge some up somewhere.
02-24-16, 04:26 PM
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Shimano Boss Covers for Road Bike Downtube Shifters Bosses Adapter Curved | eBay
That's what you want, though I don't think I could bring myself to pay $21 for them. You should be able to scrounge some up somewhere.
That's what you want, though I don't think I could bring myself to pay $21 for them. You should be able to scrounge some up somewhere.
02-24-16, 08:52 PM
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I have some of the curved ones, happy to trade for your flatties. If interested, e-mail me at rccardr@cox.net.
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02-25-16, 01:52 PM
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I understand these will work fine, I mean the base mounts securely on the down tube braze on still, it just doesn't look proper.
Is there any difference with the 7800 and 7900 shifters as far as the mounting portion goes?
Thanks for the offer @rccardr I may consider
You do realize I just threaded them on a spare frame I had laying around to take a photo right? They are back in the box and that frame is not even getting these. 
That's not the going price. https://www.google.com/shopping/prod...56245413087054
Thanks for the offer @rccardr I may consider
02-25-16, 02:07 PM
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