7sp DH V 10sp

moorey

call me Mia
Maybe belongs in the stupid Q section...

Ok, I know everyone has drunk the koolaide on the 7sp, but is there a genuine advantage over 10sp?

Looking at Felix next build, and would like (actually, will need) new wheels. Has to be Hope hoops if I’m buying new, and I know it’s just a freehub change, but didn’t want to have to replace perfectly good 10sp drivetrain for no reason.

I’m guessing it’s all proprietary anyway, with different pull ratios, and not just a matter of locking out 3 on a 10sp shifter/derailleur?

Out of my depth in this new fangled stuff :(
 

pink poodle

気が狂っている男
I'm running 7 speed on my slope/dj/commute bike, this came with the base that it was built up off rather than by choice. For the riding I do on it, it suits just fine. It does occasionally get pedalled up a steep hill. I've got Sram GX gears (mech is 7 specific, no idea about the shifter) but it is a shimano cassette spaced out on a standard shimano hub.

But to your question...I don't think there is any real advantage over 10 speed. You save the weight of 3 or so cogs and can also run a shorter chain so if Team Moore (phone changed the Moore to a devil head..?) are hard core for the micro grams there is a way. It does look nice and if your son is he'll best on it, why not? Otherwise...10 speed and a good range on the cassette. I still run weenie road cassettes (11-24/26t) on my dh bikes but a bunch of my friends are running wider range (28-32t) for those rare moments where you find yourself needing to punch out of a gully or corner and a swift skip up a few teeth can be advantageous.

I have never raced so my experiences are all recreational.
 

Dozer

Heavy machinery.
Staff member
A downhill bike doesn't need ten gears so it's seen as cheaper and more effective (I guess). My last few downhill bikes have been seven speed and the drivetrain is certainly a lot more compact and saves that bit of derailleur hang that may collect a rock or root but you're typically in the higher end of the pedaling range anyway so your derailleur will be tucked up tight.
Run the ten speed, its cost effective and works exactly the same. If you can run the chain short enough that the derailleur tucks up a bit more then do that and only tune it for the top half of the cassette.
And for Felix; always start with the foot of your weaker leg forward in the gate so your first full pedal stroke is your strong leg. ;)
 

moorey

call me Mia
Show me where this new 7sp is cheaper? I’m seeing only dearer...

Re the pedal stroke. I’d have never considered that....but I’ll wager if I tell him, he’ll say ‘duh’, politely turn around, and roll his eyes

The 7sp stuff seems to be running same cassette range as what’s available in 10sp DH cassettes....10/11-24t. Where is the option to shorten chain?
 

Daniel Hale

She fid, he fid, I fidn't
Show me where this new 7sp is cheaper? I’m seeing only dearer...

Re the pedal stroke. I’d have never considered that....but I’ll wager if I tell him, he’ll say ‘duh’, politely turn around, and roll his eyes

The 7sp stuff seems to be running same cassette range as what’s available in 10sp DH cassettes....10/11-24t. Where is the option to shorten chain?
i think he's referring if you compare x01 7spd cassette versus 10/11/12 then it is cheaper, is the gx 7 spd groupo still around? i might grab one for the SS....hey there's an idea, make felix go SS, think of the drivetrain savings--then you'd be super cool by association

7 spd is a good idea, chain strength alone -when i first bought xt 11 spd, i broke chain twice in 2 months..hadn't broken one for 2 yrs prior -when i went to the sram 8 spd e-x1, had high range but more importantly chain was solid as -havn't broken it yet (its currently waiting to go on bike to get wife riding)

PS i hate cleaning chains
 

Daniel Hale

She fid, he fid, I fidn't
Everything I read says you still use an 11sp chain. What am I missing?
crap it is an 11spd chain, where is the SRAM sense in that? you are saving some cassette weight but still have a flimsy chain, i know which will break first on a DH run. Even the Box one 7-DH uses 11 spd chain, there cassette is a svelte 195 grams though
 

moorey

call me Mia
crap it is an 11spd chain, where is the SRAM sense in that? you are saving some cassette weight but still have a flimsy chain, i know which will break first on a DH run. Even the Box one 7-DH uses 11 spd chain, there cassette is a svelte 195 grams though
What I read, claims an advantage of wider apart gear spacing on the 7sp...isn’t everyone else (including SRAM) usually pushing the advantage of close range gearing?
Doesn’t sound at all like marketing BS :D
352383
 

moorey

call me Mia
In summary:
-chain no shorter?
-chain no stronger?
-gears more spaced?
-need to buy overpriced new drivetrain?
-same basic cassette range?

I still feel I’m missing the point if it’s not already on a bike.
 

Dozer

Heavy machinery.
Staff member
Sorry, I did mean the ten speed you have is cheaper and yeah, my post sorta reads wrong.
Run the ten speed you have. ;)
 

SummitFever

Eats Squid
7spd DH seems unnecessary. Initially there were some moves to use a much shorter freehub (ie. less gears) allowing a zero dish rear wheel. I don't think the latest crop of 7spd DH stuff achieves this as the cluster is the same width as 9/10/11 speed.
 
I'm waiting for 2x10 to come back into vogue.

My 26" Enduro isn't DH but used for quite a few runs and the old girl's 2x10 speed from 2012 is still going strong. What's old may never die.
 

T-Rex

Template denier
Did the 7 speed thing back when Junior was racing U15 or U17. That was when 9 speed road cassettes were the hot setup, just replaced the two easiest cogs with spacers and fitted a longer screw for the low stop. Saved about 50 grams, looked cool, not sure he picked up any more trophies though.
 

T-Rex

Template denier
Oh, and if someone bothered to build a 7 speed specific hub, you could get wider flange spacing and a stiffer wheel, which would be mighty helpful with these modern 29 inch rims, which don't seem to last very long.
 
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