SRAM rival shifters and mechs with dura ace drivetrain?

noeyedear

Hello.. Forum (posting) newbie here, so a big hello!!!
I'm looking to upgrade some well-worn drivetrain
components on my road bike and have some compatibility
questions if you'd be so kind to consider responding...
I would like to run dura ace (7900) chainset (compact 50/34t),
cassette (12/28 ideally) and chain
with my existing SRAM Rival mechs and shifters...
Current cassette is 11/25 with 50/34 crank
Think my bike (boardman team carbon '09) has BB30 but need to check
Do I need to rethink my proposed configuration in terms of technical
compatibility?
And could I simply replace the 2 front chainrings with Dura Ace rings straight
onto my existing 5 bolt SRAM GXP crank?
Your opinions appreciated...

Pseudonym

DA chainset will run with no modifications - it's just a chainset. Providing the rings are 110bcd, then they will fit on to the SRAM cranks, but there would be no advantage in doing this - unless the existing rings need replacing anyway,,,

noeyedear

Wow, Pseudonym, that's one speedy response!
Very much obliged indeed!
I don't pretend to know what 110 bcd is (though i do see this written on my existing 50t) nor what it's 'alternatives' are,
but in general I take it that there is no need for my compatibility concerns,
which is great news! Are there non-110bcd dura ace chainrings?
So, if I understand my fairly limited research, a change from:
50/34-11/25
to:
50/34-12/28

will mean a slightly higher cadence for the same speed in top gear,
a bit more range in the lower gears for steep inclines and slightly less
close ratios across the full range of gears? Would this be roughly accurate?
Also, if I wanted replace the crank arms and front chainrings to dura ace,
would I be able to fit to my existing bb30, or would I need to replace
the bb too? indeed is this even an option? Please excuse my ignorance, any errors
in terminology and possibly confused articulation!

John.T

The Dura-ace rings would look terrible on the FSA cranks and may not even fit as they do not use through bolts.
The Dura-ace chain-set would not fit your BB30 bottom bracket. You would need an adapter and new BB cups which would add weight, complexity and reduce stiffness.
You are unlikely to notice any real advantage from changing. Plenty of good BB30 chain-sets out there if you just want to bling up.

Nigel.Mccarthy

The 09 Team Carbon has a GXP bottom bracket not BB30. Hope that helps your decision making.

noeyedear

Thank you john and nigel.. Your comments have
been most helpful!
I guess I need to rethink this one..

pastey_boy

just buy some new chainrings, a cassette and chain
http://www.ebay.co.uk/itm/FSA-Super-Roa ... 3f0c053576
and
http://www.ebay.co.uk/itm/34-TOOTH-110B ... 5ae18bd0d2
and
http://www.ebay.co.uk/itm/Sram-PG-1070- ... 746b0be6a9
and
http://www.ebay.co.uk/itm/SRAM-PC1070-1 ... 2c5d94b0b4

all this will come to approx £150 , a lot under the price of the dura-ace chainset. the chainrings are super high quality, the cassette, smooth, light and long lasting and the chain is one of the best out there. if you shop around you could probably do it for less than £100

Nigel.Mccarthy

If you wish to upgrade the chainset ie. a complete package of new chainrings & cranks then, any upgrade must be GXP compatible as that is the standard that the bottom bracket shell of the frame was manufactured with on an 09 Boardman Team Carbon. If you wish to just swap chainrings then, seeing as the supplied SRAM s350 (compact 50/34) chainset uses 110 BCD ( bolt circle diameter ) chainrings then any chainrings you wish to swap over must also use the 110BCD standard. Just to confuse matters you could get a standard GXP chainset ( usually 53/39 ) with a 135 BCD & change the chainrings to suit. I sincerley hope this clears up any confusion

Nigel.Mccarthy

I went for the easy option & swapped the s350 chainset out for a standard SRAM Force GXP compatible chainset then,I swapped the outer chainring for a SRAM TT one.

pastey_boy

Nigel.Mccarthy wrote:

If you wish to upgrade the chainset ie. a complete package of new chainrings & cranks then, any upgrade must be GXP compatible as that is the standard that the bottom bracket shell of the frame was manufactured with on an 09 Boardman Team Carbon. If you wish to just swap chainrings then, seeing as the supplied SRAM s350 (compact 50/34) chainset uses 110 BCD ( bolt circle diameter ) chainrings then any chainrings you wish to swap over must also use the 110BCD standard. Just to confuse matters you could get a standard GXP chainset ( usually 53/39 ) with a 135 BCD & change the chainrings to suit. I sincerley hope this clears up any confusion

your wrong, gxp is just the bottom bracket standard that truvativ/sram use. there is nothing stopping you fitting a shimano bottom bracket or campagnolo or any other system that fits a standard english threaded road bottom bracket shell. also a standard sram bcd measures 130mm bcd not the 135mm you mention.

Nigel.Mccarthy

Notice how I stated GXP compatible? I shall however give you the 130 BCD. It would be interesting to see somebody splash out on a BB30 chainset then wonder why it does not fit. Would you agree?

pastey_boy

Nigel.Mccarthy wrote:

Notice how I stated GXP compatible? I shall however give you the 130 BCD. It would be interesting to see somebody splash out on a BB30 chainset then wonder why it does not fit. Would you agree?

you quoted "If you wish to upgrade the chainset ie. a complete package of new chainrings & cranks then, any upgrade must be GXP compatible as that is the standard that the bottom bracket shell of the frame was manufactured" and that is not the case, it does not have to be gxp compatible.

noeyedear

sick wheels, Nigel, absolutely sick

noeyedear

pastey_boy

seems you've done my shopping for me!!

for want of a better word, that's bleedin' awesome

thank you!