Changing Cranks

[heist]

Hey I have a Vitus Razor VR (2014)

It came with Shimano Claris cranks and the rest of the groupset is Sora, I am looking to replace the bottom bracket and the cranks to Sora.

I know the current crankset uses "octolink" and the Sora uses "hollowtech II"
I am going to check the crank length, which I believe to be normally 170 or 175?? (I will get the same, as happy with the length I have)
I believe the BCD is the same, I willl double check, but I think its 110BCD

What else do I need to check, Do I need to the bottom bracket length? or is that fairly standard?
Do I need to do anything else?

Hoping to buy this
http://www.ebay.co.uk/itm/Shimano-S...t=LH_DefaultDomain_3&var=&hash=item2ed92643e0


Thanks
Matt

 

[Pale Rider]

My trusted bike mechanic reckons Hollowtech is one of the better innovations in recent years, so the conversion, if possible, is worth doing.

One point to bear in mind with Hollowtech is frame facing.

Because it's an external bottom bracket, it is critical the two faces of the frame are flat and parallel.

If not, the bracket will not run true and will wear quickly.

Even a coat of paint can knock the bracket out of line, although a tiny misalignment is not likely to cause a problem - sense of proportion needed.

A competent bike shop can face the frame.

 

[accountantpete]

I would get your LBS to remove the octolink BB as presumably there is no point in getting the special tools needed if you wont need that system again.

Then you will need a special Hollowtech installation spanner which is worth getting.

http://www.ebay.co.uk/itm/like/1717...1=ICEP3.0.0-L&ff12=67&ff13=80&ff14=108&ff19=0

Your BB shell width should be 68mm so you just need the road version of the BB (any road groupset version of the BB eg Tiagra,105 Ultegra etc will be for 68mm BB's)

You can then either get the Sora cranks and transplant the chainrings or shop around for a slightly better alternative like the Tiagra chainset

http://www.wiggle.co.uk/shimano-tiagra-4650-hollowtech-ii-10-spd-compact-chainset/

 

[User6179]

As above I would recommend Tiagra Chainset , replaced my Ultegra with Tiagra and they are as durable if a little heavier , the Tiagra BBs though don't seem to last as long but they are cheap to replace .

 

[Citius]

As above. Claris to Sora is a fairly pointless exercise. Make it worthwhile by going for at least 105.

 

[subaqua]

My trusted bike mechanic reckons Hollowtech is one of the better innovations in recent years, so the conversion, if possible, is worth doing.

One point to bear in mind with Hollowtech is frame facing.

Because it's an external bottom bracket, it is critical the two faces of the frame are flat and parallel.

If not, the bracket will not run true and will wear quickly.

Even a coat of paint can knock the bracket out of line, although a tiny misalignment is not likely to cause a problem - sense of proportion needed.

A competent bike shop can face the frame.

threads inside BB that need to be done properly too Even a 73 has plastic spacers. Have just changed the octal ink BB and chain set on my commuter to a Deore and hollow tech 2 . Only because I couldn't find an octalink chain set with same teeth and crank length .

 

[heist]

As above. Claris to Sora is a fairly pointless exercise. Make it worthwhile by going for at least 105.

What options do I have for 9 speed?
Cant seem to find much else.

 

[adamhearn]

You can usually use 10 speed cranks with a 9 speed drivetrain. You may need a 10 speed chain but worth a try before you buy.

 

[Cubist]

I stand to be shot down, but a 10 speed chainring will work with a 9 speed chain.

 

[Citius]

What options do I have for 9 speed?
Cant seem to find much else.

The cranks don't care how many sprockets your cassette has. Any 10sp crankset will do.

 

[T.M.H.N.E.T]

I stand to be shot down, but a 10 speed chainring will work with a 9 speed chain.

I use this exact combination

 

[Smokin Joe]

The cranks don't care how many sprockets your cassette has. Any 10sp crankset will do.

Spot on.

And a 2014 frame will almost certainly have had the BB shell faced for outboard bearings as standard, that being that is the norm now.

 

[heist]

Just want to double check. I have been looking on the net to see what I want to get, just wanted to clarify.. Do compact cranks normally have 110BCD and doubles are 130BCD??

 

[Citius]

Compact double 110
Standard double 130

Both are doubles

 

[jnrmczip]

Are you buying a triple or double front crank. I got the octalink removed and sora put on my bike but as one is internal and the other external need to male sure the crank and chain don't rubbish the front deruler with the difference in bottom bracket