First (Disc) CX build: Advice?

[ANAO]

I was offered a Cannondale Disc frame. I've never built anything with a disc before. I can figure out the rest, but fork? rotors? brakes?

Steer me, please!

[kramnnim]

Hmm, looks like Cdale didn't go with the usual 1.5" tapered fork, so no ENVE. (or the one I mentioned on FB)

Quite happy with my TRP Spyres... The HY/RD looked interesting, but weigh more. I think there was a recent thread about rotors and Icetechs sounded like the winners...

[foo_fighter]

Are you transferring an old group or getting all new? If new, you will need to decide whether you want to go full hydro or not. Shimano Freeza(ICE tech 2 piece) rotors are well regarded.

[ANAO]

Originally Posted by foo_fighter

Are you transferring an old group or getting all new? If new, you will need to decide whether you want to go full hydro or not.

Please elaborate.

[Dave B]

I used the basic Avid BB7 ones on mine and they worked great.

I used to waaay over think this for cross, I simply had to race to understand it is more about when the brakes are applied then their strength. With any disc, you will be able to stop. I ran 160mm up front and 140mm in the rear...but I am fat, so it was smart for me.

I don't see hydro stuff being terribly important unless you simply want that. Go for some mechanical ones with 160 or 140mm rotors.

these are just some quick thoughts. Don't over think stuff unless you are looking for a show bike. NO when it comes to rotors this is where people get pretty snippy. Typically I think of mtb discs and go for mud shedding and the shimano ones have always done well. Now, if you are ina very sandy course you are going to want solid rotors. The ones with big cut outs that she dmud also take that sand and file down your pads in a lap or two. Some of the pros are using low end avids I think (just rotors) that are almost solid looking. Ryan Trebon (sic) used them for worlds or nationals inthe US and was able to last longer before switching bikes.

Again just thoughts.

[Gummee]

If this is *just* a race bike, then run Spyres, Avids, or what have you and change out the cables a few times over the season. Compressionless housing seems to really help.

If this is for more of a gravel grinder during the year that you race in the fall/winter, then 685s and the fully hydro brakes are indeed much nicer.

At least around the mid-atlantic, there's maybe a few races that you NEED discs for. The rest are usually pretty dry.*

M

*watch this winter be the exception now that I've said that.

[brando]

Can't beat shimano hydro

[foo_fighter]

Haha, good one.

Basically, Full Hydro systems like Rival,Force,Red HydroR, and Shimano RS785/685 will quickly take over the Road/Endurance disc and possibly CX market. If you are getting a new groupset anyway, the only reason the stay with cabled brakes, are due to budget or you are possibly waiting for a full wireless/Hydro system from SRAM or don't want to learn to service/bleed the brakes.

If you are sticking with cabled brakes then, HY/RD > Sypre > BB7. You just won't get the feel and modulation of a full hydro system.

A bigger question may be if you want 1x11.

Originally Posted by ANAO

Please elaborate.

[ANAO]

Probably (a gutted and converted) 1x10. The idea here IS a somewhat budget-conscious build.

[oldfatslow]

Originally Posted by kramnnim

Quite happy with my TRP Spyres...

+1 on the TRP Spyres. I have the Spyres on my adventure tandem. They have great modulation and huge stopping power.

They are also wildly easier to set up than the AVID BB7's and employ a dual piston design which I believe is superior to designs which have one piston.

[ANAO]

Originally Posted by Gummee

If this is *just* a race bike, then run Spyres, Avids, or what have you and change out the cables a few times over the season. Compressionless housing seems to really help.

If this is for more of a gravel grinder during the year that you race in the fall/winter, then 685s and the fully hydro brakes are indeed much nicer.

At least around the mid-atlantic, there's maybe a few races that you NEED discs for. The rest are usually pretty dry.*

M

*watch this winter be the exception now that I've said that.

Mark donated an old beater set (THANKS MARK) of BB7's which need new pads. This will be a race rig, so I figure (based off my copious amounts of internet-research) those will be perfect for my applique.

But they need new pads. What kind should I get?

[miguel]

hi,
i've had 5 road/cross/gravel/rando bikes in the last 4 years that were full disc or mulleted and i have opinions. i have roughly 7000kms this year on a few different sets of mechanical disc brakes and have tried most of the bigger brands (bb7, cx77, spyre, rever, etc).

1. Go hydro. Get the shimano 785/685s or the trp hylex. You will not be disappointed, this is the best you can get for the money.

2. Use shimano ice tech rotors.

If you follow these two things you will be happy.

try to get centerlock hubs and rotors because all the best (shimano) stuff is going to be CL.

You cannot use icetech rotors with BB7s without modification to the pads. BB7s suck anyway so dont use them and you wont have to worry about modification. The stock avid clean sweep rotors have been lovingly referred to as "cheese graters" and, when they're not eating up pads, they are loads of fun if you ever accidentally bend them a bit. But BB7s suck, dont use them. cx77 are a similar design to the bb7 but weigh less are are less sketchy. i have a set on a bike right now. they work.

the Spyre and Rever brakes are very similar, the rever has a few new details but i'm not totally sold on them yet. what they have going for them is a little more clearance for the front and modern shimano pad usage. the spyre stock pads are absolute garbage and should be thrown away if you are using them longer than 2 weeks in light rain. get shimano (i think "g"?) pads.

one difference between the single and dual piston mechanicals is the singles are a bit louder than the duals. when you set up your stupid bb7s you will find out how loud and annoying they are. resin pads will help but it wont stop. i pity the fool that puts sintered/metal pads on a single piston brake.

use nice compressionless housing for all these mechanicals and you will be happy.

160 rotors are good for front and rear, some people use 140s on the rear. i havent seen 140s on the front but i would imagine for cross it might work because you are not coming to absolute stops or doing long mountain descents. it's kind of awesome to see steam coming off the rotor in a cool/wet climate, this last winter was lots of fun.

the thing about disc brakes is there is a weight penalty. any way you cut it a disc brake set is going to weigh more than a weenie rim brake set - but ATMO the benefits are better. except with bb7s. they're heavy, loud, and they always need adjustment.




i guess whisky makes a 1.125 straight steerer fork but you might as well just buy any old china carbon. i guess wound up but those look funny. or maybe you should buy the steel tange prestige fork i tried to sell you in the other thread. weight penalty vs ride quality, steel fork with good pressure is a pleasure to drive. you wont find a carbon fork with fender/rack mounts and that's always good when you dont actually want to race anymore.

[erslah]

Go with Avid BB7 organics. They don't last quite as long as the metallic version, but I thought they had better grip in our muddy Oregon CX races last year.

--Eric

Originally Posted by ANAO

Mark donated an old beater set (THANKS MARK) of BB7's which need new pads. This will be a race rig, so I figure (based off my copious amounts of internet-research) those will be perfect for my applique.

But they need new pads. What kind should I get?