Can my Scott Speedster S3 upgrade to new 105 crankset?

[cjhcjh]

Hi,

I have a 2005 Scott Speedster S3 currently running 3rd hand 7s 105 and some heavy Octalink crankset. It was originally sold with 105 triple and a BB of "Tien Hsin BB-5503". online specs here: http://www.bikepedia.com/quickbike/BikeSpecs.aspx?year=2005&brand=Scott&model=Speedster+S3+27-speed

will the cranksets of new(ish) shimano / FSA 10speeds fit on my frame, or is the frame just too old to be compatible?

thank you in advance

 

[alfeng]

FWIW. Unless the current BB is shot, you will probably find very little advantage in changing cranksets UNLESS you are making the change for cosmetic reasons (nothing wrong with THAT as a reason) ... Your SCOTT frame has a standard 68mm wide, English threaded BB (AFAIK, Octalink BBs were only available for standard English BBs + Italian threaded BBs).

• If you want to install either a Shimano Hollowtech II or FSA MegaExo crank on your bike then you just need the proper installation tool for the new BB cups. MANY people will recommend facing the BB shell ... I believe that is an unnecessary procedure on most frames ... HOWEVER, THAT does not mean that you should not ensure that the BB shell's faces are square. MANY people have suggested that FSA BBs do not last as long as Hollowtech II BBs ... I can neither validate nor refute that ... Hollowtech II bearings are better shrouded than FSA's bearings ... whether or not that makes a difference is NOT known to me ... I can suggest that if you opt for MegaExo cups that you slather the inside of the cup with grease where you can see the cartridge bearing ... it's probably a good idea to slather some grease on the inside of a Hollowtech II cup, too.

FYI. The 105 crankset is not particularly heavy, IMO.

• A (silver) 5500/5503 crankset is really just an unpolished Ultegra 6500/6503 crankset with different chainrings OR you can think of an Ultegra 6503 crankset as a polished & anodized 5503 crankset with different chainrings ... Of course, the "black" 5500/5503 cranksets were painted.

If you are NOT using the Granny AND/OR the BB is shot, you can always simply replace the current "Tien Hsin BB-5503" (who knew there was a non-Shimano Octalink BB?!?) with a 109.5mm 105, Ultegra, or Dura Ace Octalink BB ... OR, depending on the current chainstay clearance with your crankset, you may/should be able to use a 112.5mm XTR Bottom Bracket with the Triple OR with just the outer two chainrings if THAT is more readily available ... the XTR BBs are designed for a 73mm shell, so you will need to use the spacers which come with the BB. BTW. How do you only have a 7-speed configuration? What shifters does your bike currently have?

 

[cjhcjh]

Thank you Alfeng.

That in-depth reply was a great help in my final decision to upgrade to 105 5700 full groupo.

I don't like 'throwing money' at problems, but the new groupo cost about $50 more than replacing the shifters and crank set. Including cables it came out around even for the whole upgrade. It was well overdue especially considering at the start of a ride the right shifter was needing the left shifter to help the RD move [odd!?!]. Although the shifters did see 10-15 years of a hard commuting (lots of rain), so a life well lived.

I was wrong, it was an 8 speed. I cannibalised and old Klien that had 7s 600 groupo and that was the last time I counted.

I've now come to the connundrom that the 105 5700 compact crankset isn't low enough with my 12-27 cassette. I'm after some hills that need something more. I'm about to start a new thread for that and would be interested in your thoughts on that if you're keen.

Thanks again, it was a great help in a procrastinated upgrade.