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Old 02-22-11, 05:17 PM   #1
purplewombat
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Converting a '01 lemond poprad for touring, please help!

So a few months ago I decided to go tour the southern tier. I've been a bike commuter long enough to keep my bike in decent working order and am comfortable with routine maintenance, but I decided I wanted to teach myself some more about the in depth workings of my bike and swapping components, and so made what is now seeming like the very dumb decision to try to make my '01 lemond poprad suitable for touring.

I initially had a 9 speed with 52/39 ultegra double crankset and figured I'd just switch out my derailleurs for long cage ones, and go with a 52/42/30 road triple crankset with a wide range cassette in back. This sounded great in theory, and I got as far as swapping my crankset and front derailleur, trading my double sti shifters for triples, and getting a triple rear derailleur, but I went to my local bike shop to get their advice about a cassette, they told me that my frame is too short to accommodate a triple crankset.

I'm a little unclear as to the details of the explanation, basically that my inner ring would create an impossible chain angle? If anyone can explain that to me in a way that makes more sense I would appreciate it, sorry for not being better at explaining.

Anyways, my question is: is there any way I can make this bike work with the components I have, or is my frame really not suitable? The folks at the bike shop recommended going with a compact double, but I am not a strong hill climber in the slightest and am somewhat wary of that plan. Any advice or recommendations would be extremely appreciated.... I'm leaving next week so am a little bit in last minute panic mode about suddenly needing to drastically rethink my bike. Thank you!!
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Old 02-22-11, 05:25 PM   #2
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try using a longer axle (bottom bracket ) to push out the chianrings to clear the frame, after you do that then everything will work.
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Old 02-22-11, 05:40 PM   #3
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Thanks! I tried it with an 118.5 bottom bracket, do you have any recommendations of a longer bottom bracket that is still going to be compatible with ultegra cranks?
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Old 02-22-11, 05:58 PM   #4
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Originally Posted by purplewombat View Post
Thanks! I tried it with an 118.5 bottom bracket, do you have any recommendations of a longer bottom bracket that is still going to be compatible with ultegra cranks?
Based on the information in your posts, it sounds like your crank is an Octalink version (i.e., FC6503). Shimano made one Octalink BB length for doubles (109.5) and one for triples (118.5).

Why do you need a longer BB?
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Old 02-22-11, 06:01 PM   #5
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apparently my chain line still didn't have enough clearance with an 118.5?
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Old 02-22-11, 06:26 PM   #6
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Are you stating that the inner chainring is too close to the chainstay? If so, you could probably use a shim under the DS cup to add another mm or two clearance. You could also gain some clearance by switching to a smaller inner ring, such as a 28t.
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Old 02-22-11, 06:38 PM   #7
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You plan JRA touring or are you wanting to haul full panniers up mountain passes?

since cassettes are made for compact mountain drive trains \11 or 12 to 34 t

You really dont need that 52 t chainring [52:12=4.3:1] and the 30:34 low
will require young strong legs..

Proper loaded touring bikes combine MTB 9 speed stuff with Bar end Dur Ace shifters
that work with compact cranksets and their front derailleurs
Road triples have a different cable pull Brifters have trouble with those Compact FD's

+ you will find chainstays on well designed touring bikes are longer for a purpose ..
not kicking the bags with every pedal stroke.. is just one.
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Old 02-22-11, 09:06 PM   #8
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Yes, inner chainring is too close to the chainstay, thanks for phrasing that better than I did. Would I be able to just swap out my 30t chainring for a 28t and still shift smoothly or would that necessitate swapping the other two chain rings as well? I'm planning on hauling panniers up mountain passes... I definitely realize that what I have is far less than ideal, but I'm unfortunately getting super close to my departure date and don't really have the time or finances to deviate too far from what I already have on hand. Thanks so much for all the advice everyone!
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Old 02-23-11, 12:21 AM   #9
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Your crank will accept a 28t or 26t inner ring, and various posters on these forums have installed a smaller inner ring on their road triple cranks when they've wanted the lowest possible gearing. But you really shouldn't expect the same quality of shifting. Shimano designed the stock ring combination to work together as a system, and any modification from the stock arrangement will have an effect. I'd expect the upshift from inner to middle ring to require slightly more patience due to the larger tooth difference, especially with STI shifting. I'd also anticipate the increased possibility of dropping the chain off the inner ring. At minimum, I'd make every effort to get the FD adjustment near perfect, and I'd install a seat tube-mounted chain catcher (e.g., Dog Fang, Third Eye, etc).

As fietsbob suggested, bar end shifters with a "trekking" crank (Sugino XD2) would have provided highly reliable, fuss-free shifting with practical gearing. But I understand your issues of time and money, hence the thoughts of switching out the inner ring.

Try searching the forum for firsthand experience with 52/42/26 and indexed shifting. Or maybe ask in the touring subforum.

Oh, you mentioned possibly switching the middle ring, too. To my understanding, Shimano made their 42t middle rings to work with one type of 52t large ring, while a slightly different design of 52t ring was used in combination with 39t middle rings; thus changing one would theoretically mean changing the other when used with indexed shifting.
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