New CX bike build - advice needed

tgotb

Just picked up a CX frame; plan is to build it up and use for everything from commuting in the snow, to the odd race. Few questions:

1. The frame has attachments for both disk brakes and cantis; which should I fit, and why?
2. What rims do you recommend for a 90+kg rider? Currently commuting on 32-hole Open Pro, will these be up to the job for CX?
3. Do I want to fit cross top levers (if that's what they're called)?
4. I've heard there can be issues using some brakes (eg V-brakes) with road levers. Does this mean I need disk/canti brakes that are specifically designed to work with road levers?
5. Anything I need to know about CX saddles? I've got a Rolls on everything except the TT bike, will one of these do for CX too?

Thanks in advance!

meanredspider

Can't comment on the CX racing itself but I can on the brakes side of things

- I'd definitely fit discs - BB7s seem to be the current favourites - you might still find them cheap.

- Cross top levers I assume are what I know as suicide brakes. I thought I'd find these useful but, TBH, because I have discs on my Boardman CX, I don't. I get plenty of braking force even on the hoods. What I have found is that they get in the way of fitting lights etc on the bars and they are one extra thing to adjust too. Given the choice again (and in future upgrades) I'd do without them. CXers and other might disagree.

veronese68

Try riding my bike with cantis down Richmond hill in the dry. Then buy discs. Road levers don't have enough cable pull for V brakes. I believe Avid do discs for road levers, not sure why you can't use normal ones. I believe Hope do a cable pull hydraulic pump so you can use hydraulic discs. Decent hydraulic discs are better as the push both pistons. Cable brakes pull on one side and have a sliding caliper to exert pressure on the other side.
Don't know much about CX saddles. Soft enough to cope with a rushed re-mount sounds like a sensible choice to prevent numb nuts. I'm sure others will advise.

61Sigs

I'm currently in the process of getting a cx, for what it's worth:

Now they're legal I'd go for discs, they work better and collect less mud etc.

Suicide levers, probably nice to have on the road, but you're still going to have to move further down to change gears, so just get in the way.

cjcp

As you want it for commuting, I'd go for disc brakes - as 61sigs says, they're now race-legal. My cantis worked fine (to the extent that cantis "work fine") with my Ultegra STIs.

Re wheels: check what width tyres the rims can take. I've got 30mm tyres and do the job. I used 32-h CXP33s, so the Open Pros should be fine.

Re tubes - get tubes to fit the wider tyres.

ride_whenever

Most mtb mechanical disc brakes are designed for v-brake pull so don't work well with STI's. The avid bb5 road and bb7 road are designed for STI pull so work, and do so really well.

Cross-top levers aren't the same as suicide levers (suicide levers were the ones built into the hood of the old weinmann brake and were lethal hence the name, crosstops are in-line levers) crosstops are great on commuters for really sketchy days and heavy traffic as they bring your weight a bit more central.

On the rims, personally I don't like the mavic rims too much. I'm currently running halos, but for large riders like us, the build is way more important than the actual parts. So get a good builder to make them.

For saddles ride what you'd like but you might want something a bit more durable than a rolls for CX.

mudcovered

TGOTB wrote:

Just picked up a CX frame; plan is to build it up and use for everything from commuting in the snow, to the odd race. Few questions:

1. The frame has attachments for both disk brakes and cantis; which should I fit, and why?
2. What rims do you recommend for a 90+kg rider? Currently commuting on 32-hole Open Pro, will these be up to the job for CX?
3. Do I want to fit cross top levers (if that's what they're called)?
Thanks in advance!

Road compatible discs would be my preference on the braking front. I've got a CX bike with cantis fitted and I don't have any performance issues with them now but I had to do a lot of tweaking to get them to that state.

On the rims front I'm also around 90kg and commute 20 miles a day with half of that being on mud and gravel towpath. I used to run Mavic Aksiums. After a truing tweak about 3 months after I got them they ran just fine until I wore out the braking surface after about 600miles. I'm currently running on 32h OpenPro rims built around hope hubs. Had to get the rear wheel rebuilt after about 5000miles as it had started popping spokes every couple of months. Rim was still fine though and is now going strong again after my LBS replaced all the spokes with slightly beefier ones.

I've got the cross interrupter levers on my bike. They do limit the amount of space on the bars for lights/computers etc but they are useful on occasion. However I could easily live without them.

Mike

tgotb

Thanks guys, that seems pretty clear. I've had enough of brakes that "just about" work on the TT bike, so disks it is.

Next question: On a road bike, 8/9/10 speed hubs are all compatible (sometimes with spacers). Will an MTB hub advertised as 8/9 speed take a 10-speed road cassette? I assume MTBs don't have 10-speed yet...

howards

9 speed Deore MTB hubs fit a 10 speed road cassette no problem.

I have SRAM X9 MTB hubs running 10 speed road cassettes, again, no problem.

bails87

Lots of MTBs (even with 'entry level' Deore kit) are 10 speed nowadays I'm sure all 8/9/10 speed freehubs are the same size, as people put 10 speed road cassettes on MTB hubs with no problems.

Aidy

TGOTB wrote:

Thanks guys, that seems pretty clear. I've had enough of brakes that "just about" work on the TT bike, so disks it is.

Next question: On a road bike, 8/9/10 speed hubs are all compatible (sometimes with spacers). Will an MTB hub advertised as 8/9 speed take a 10-speed road cassette? I assume MTBs don't have 10-speed yet...

You assume wrong, 10 speed is widely available now. (Although, I'm stubbornly sticking to 9 speed).

Obviously you'll want Shimano fitting cassettes, though.

Out of interest, what frame is it?

tgotb

Frame is a Voodoo Wazoo; arrived yesterday. Curiously, the forks have the same sticker as my road and TT bikes, with a warning that they're unsuitable for off-road use. Must be a legal thing, they certainly look like they're up to the job...

Rest of the stable is on Shimano/SRAM, so cassettes aren't a problem...