Advice needed to upgrade crank set
 

My Allez Double Steel has a Shimano 2300 crankset with 52/39T chain rings. I would like to upgrade to a Shimano Ultegra FC-6500 39/53T mainly because it looks a lot cooler, and perhaps could save a little weight. I have a few (possibly dumb) questions:

1. What exact type of Octalink bottom bracket will I need to buy (thread type and shaft length?)

2. As the large chain ring has one extra tooth, will I need to move the forward derailleur up to make room?

3. What type of crank puller and bottom bracket tool/s will I need?

4. Will there be any issues with alignment between the new chain rings and the 8 speed cassette that I might need to deal with?

Thanks!

Dale

1. The same thread type you have in there now. What that is, I don't know. You'd have to tell us. I believe that Specialized used English threaded shells on all their bikes, but I'm not sure. Spindle length should be 110mm for that crank.

2. Maybe. If you're replacing the crank, the derailleur will need to be completely readjusted anyway. May as well just do it.

3. Standard crank puller that has a splined-crank compatible side or adapter will work fine. BB tools will depend on what you've got now (you haven't mentioned) and what BB you choose for your new crank. If you get a matching Shimano BB, a very common 20-tooth splined tool is all you'll need besides a wrench to spin it.

4. No, but you should re-adjust all the derailleurs afterwards.

1) 68mm 1.37x24 English 109.5 Octalink v1 Either the BB-5500, or the BB-7700/7710. 105/Dura ace version. You'll have trouble finding the ultegra version of that bb-6500
2) Double check correct clearance 1-3mm at the top. One thing you did miss is double checking that the chain length is correct. If it was already too short, or marginally short on the 52 x blah then it'll probably explode.
3) Park Tool CCP-44 http://www.parktool.com/images/produ...08114_3657.jpg
4) Not even sure what that means.

1. Octalink V1 109.5 mm, English threaded as noted. BB-5500 is good and relatively cheap. BB-6500 is out of production and difficult to find even NOS. BB-7700/7710 is pricey and requires routine maintainence. Any of these will work.

2. Yes

3a. All require the same Shimano or Park Octalink/ISIS bb tool. Park's newest versions are the BBT-22 and BBT-32 Both work but the BBT-22 is a bit heavier and more versatile.

3b. The 6500-series cranks have auto-extractors built into the crank bolts so, in theory, you don't need a separate crank extractor at all.
You can use a small pin spanner to remove the autoextractor collar to clean everything inside before reinstalling the crank and to be able to look and see the splines are aligned correctly before torquing the crank bolts down. A pair of needle nose pliers with small tips will work as a substitute.

4. No.

wow that is alot of time and money for one tooth a few grams of weight and bit of "cool".

I just wanted to correct you on the 7710 - that unit is not the same as the 7700, which does require periodic frequent maintenance (essentially a looseball octalink bb) The 7710 unit is like any other standard shimano cartridge (e.g square taper or the 105 octalink), there is nothing to service and it is much better for road use.

This is the 7710 unit.

http://businesscycles.com/graphics/tbb-7710.jpg

And the 7700.

http://businesscycles.com/graphics/bb7700a.JPG

Many thanks for great advice....I even get pictures! :)

I agree with Bianchigirll, it is a lot of effort for a small return but it would be fun to do if I can pluck up the courage....

Perhaps I have a justifiable reason to upgrade my crank (other than an ounce of weight and cool factor). Based on these calculations, its critical that I get a longer crank! :-)

Inseam length in inches: 33
Inseam length in mm: 838
Max leg-crank ratio: 0.216
Min leg-crank ratio: 0.21
Max crank length: 181.008
Min crank length: 175.98

What do you think? (I forget where i found the ratios).

Beh, screw "fit" calculators. Go get fit by a real human who has a good reputation for fitting road cyclists, especially racers.

Fit calculations are a good source for conversation. To get a proper fit you really need a human with (preferably) years of cycling/racing or practical on hand experience (or all of the above). Many fit calculation formulas do not take into account health issues/riding style/age and other topics that only a experienced fitter can do. There is no common sense when doing a formula to get a fit. Theyare usually done "by the numbers". Someone that used a fit formula and came up with -- 175.98 min. crank length -- but is a beginner and is 55 years old may be better suited by having 172.5 cranks. Being fitted properly isn't as easy as just using a formula.
'

Good info and thanks for the correction. BTW, wasn't the triple version of the "Dura Ace" (7703?) Octalink also a sealed unit and only the double was the loose ball type?

I have personal experience with both the 6500 and 5500-series Octalink but only "book learning" about the Dura Ace ones.

The 7710 was the DuraAce track version. I always used the 7700 and didn't mind o'hauling it. I would treat the o'haul like a wheel build - like therapy. I believe there is 72 bearings (2 rows of bearings each side). The 6500 was much easier to deal with and many pro teams used the 6500 because it was a no maintenance BB.

The 7710 is identical to the 6500 accroding to someone who actually cut them open. The 7700 version is lighter and with removal of all the seals can be made to spin MUCH, MUCH better than the 7710 version. Ideal for track use.

Inform the person who cut open helpless BB's that the difference between the 6500 BB and the 7710 BB is -- Total weight. The weight difference is because the 7710 comes with a steel NDS cup vs the aluminum cup on the 6500. So needless to say the 7700 is much lighter than the 7710. Go ahead and remove the 2 seals from each side of the 7700 but you will be o'hauling the BB more often. If you are looking for spinning just remove the 2 outer seals on the 7710 and it will spin very nice and maybe even smoother than the 7700. Use whatever BB you want at the track but the Shimano 7710 is labeled as "Dura-Ace Track" on the box. I have 1 at the store.