Trying to build a super cheap disc cross bike - how's this look?

[Dead Man]

Traitor Ruben steel disc - $250 used excellent condition
RSX 7 speed group - already have
160mm TRP hy/rd - $204/two at Merlin
Wheels - need some inexpensive hubs and rotors.. Have rims.. $150? Rwcently gave away some EC90 Aeros that would have been perfect ... Didn't know I was gonna do cross! So maybe I just roll some box section clinchers for now.

I THINK the 7 speed freehub cassette will work on 8/9/10 freehubs...? Or at least I am banking on that. Otherwise this whole plan is gonna fall apart on me, and I might as well just try to find a cheap rim brake CX bike on Craig's..

Gearing I have is 13-26 and 42/52... Cranks are 170, and I like 175s.. So I might just find a cheap 36/46 somewhere.. But my thought was I could probably get away with just treating that 42 like a 1x and cross chain it

Thoughts? See any potential issues or incompatibility I am missing?

$600 out of pocket for what I think should be a pretty damn bomb proof disc cross bike!

[weisan]

http://www.nashbar.com/bikes/Product_10053_10052_574097_-1___204687

$599

[Dead Man]

That ain't disc though

[gdw]

You'll need a spacer to run a 7 speed cassette on a 8+ speed freehub, they're cheap. What is the rear spacing on your frame, 130 or 135?

[kramnnim]

Spyres would make it a lot cheaper...

[Dead Man]

Are the hy/rds not significantly better, though? Looking for the best braking I can get without going full hydro and therefor full new group)

Kind of a delicate balance between "super cheap" and "super rad" I guess.

Spacing - I was sort of assuming 135, but it's a few years old so maybe not - I'll need to double check that.

Eta- it's 135.

[kramnnim]

I went from Spyres to Shimano hydro and the Spyres are fine.

[Dead Man]

I went from Spyres to Shimano hydro and the Spyres are fine.

Does that mean you've got a righteous deal on them for me?

:)

[kramnnim]

Mine are SLCs, and I don't have rotors to go with them, so not ideal.

[John H.]

I think you will have exactly $600 worth-

[oldfatslow]

I went from Spyres to Shimano hydro and the Spyres are fine.

If Spyres can stop my 350lb tandem on a 10 mile descent they will work for a single racing cross. They are super easy to adjust and perform really well.

[Dead Man]

I think you will have exactly $600 worth-

Is that enough to win races?

[oldpotatoe]

Traitor Ruben steel disc - $250 used excellent condition
RSX 7 speed group - already have
160mm TRP hy/rd - $204/two at Merlin
Wheels - need some inexpensive hubs and rotors.. Have rims.. $150? Rwcently gave away some EC90 Aeros that would have been perfect ... Didn't know I was gonna do cross! So maybe I just roll some box section clinchers for now.

I THINK the 7 speed freehub cassette will work on 8/9/10 freehubs...? Or at least I am banking on that. Otherwise this whole plan is gonna fall apart on me, and I might as well just try to find a cheap rim brake CX bike on Craig's..

Gearing I have is 13-26 and 42/52... Cranks are 170, and I like 175s.. So I might just find a cheap 36/46 somewhere.. But my thought was I could probably get away with just treating that 42 like a 1x and cross chain it

Thoughts? See any potential issues or incompatibility I am missing?

$600 out of pocket for what I think should be a pretty damn bomb proof disc cross bike!

XT or Deore disc hubs are really cheap..like in the $60-$90 range for the hubset.

[eBAUMANN]

I have a complete 9s ultegra group with 175mm 48/38 crankset I'd sell real cheap if you're interested. 12-27 caseette, 28.6 fd...just an idea.

Also would definitely recommend spyres, they are fantastic brakes, I doubt hy/rd are THAT much better.

[John H.]

Do you win races now?

Is that enough to win races?

[Dead Man]

Do you win races now?



I haven't done CX in about 3 years .. And no, wasn't winning. Which is why I quit. But my fast twitch twitches much faster these days, and I sorta missed the road season this year, so I'm gonna give it a try.

I don't think the bike is gonna hold me back, man. And if I do well, and upgrade out of beginner cat quick, I'll know it's really for me.. And build something nice.

[dustyrider]

Some of the early Rubens were a bit tight in the tire range department. You looking at the newer ones?

I see crusades pop up pretty regularly on eBay or pink bike for a bit more money. I don't race cross for anything but fun and not all that often. I would most likely want a flat bar with mtb hydros and either 1x or SS. One of these days...

[Dead Man]

55mm in the back, 44 in the front. Widest I'll run is 34, so should be good.

[ikecycke]

I've ridden Spyres and Hy/Rd, you're not really giving up anything with the Spyres and saving a lot of money.

[sandyrs]

I have a complete 9s ultegra group with 175mm 48/38 crankset I'd sell real cheap if you're interested. 12-27 caseette, 28.6 fd...just an idea.

Also would definitely recommend spyres, they are fantastic brakes, I doubt hy/rd are THAT much better.

I would take Eric up on this just because RSX shifters have proven unreliable for me in the past, and a quick Google search makes it clear I'm not the only one whose shifters have gummed up and been rendered useless.

[Dead Man]

Word.. happens to be I did go with Spyres, and will probably even go 6500 instead of the RSX, since my realization that I need a top-pull front der and a 115mm BB. Just doesn't really "save" me any money to use the RSX, factoring those. Eric's group is sold, but I'm talking with another Paceliner about his 6500 shifters, and then I'd just need to score a cheap 6500 rear der. Gotta make sure 6500 left will work with the CX70 der though (anybody know if the pull ratios change between 6500 and 6700?)

This RSX group has been good to me in wet and dry conditions, though.. have no reason to think it'd give me problems on the CX bike, but who knows?

[benb]

Go buy a $600 hardtail MTB and ride that. As long as you're racing at a level where it's allowed it will be very very competitive and will have fully Hydro Shimano brakes if you're lucky.

A cross course is just a really easy X/C MTB course in the end.. if they don't have a ban on flat bars they work great.

Example: Specialized RockHopper Sport for $625. Comes with shimano hydraulic brakes and 29x2.1" tires. Probably not a terrible tire for Cross.

[sandyrs]

Word.. happens to be I did go with Spyres, and will probably even go 6500 instead of the RSX, since my realization that I need a top-pull front der and a 115mm BB. Just doesn't really "save" me any money to use the RSX, factoring those. Eric's group is sold, but I'm talking with another Paceliner about his 6500 shifters, and then I'd just need to score a cheap 6500 rear der. Gotta make sure 6500 left will work with the CX70 der though (anybody know if the pull ratios change between 6500 and 6700?)

This RSX group has been good to me in wet and dry conditions, though.. have no reason to think it'd give me problems on the CX bike, but who knows?

I could be wrong, the ones I had came very well used so if they're well cared for I'm sure they'd be fine on the cross bike!

[Dead Man]

https://scontent-sea1-1.xx.fbcdn.net/v/t1.0-0/p526x296/14237600_323708267972437_5402285113252362319_n.jpg ?oh=bb3eb223e3680255712445fa17466046&oe=584C9427

Got the rear caliper on today (a IS>PM +20mm adapter isn't super hard to find, but everything is when you live 40 miles from the nearest bike shop), and took 'er for a quick ride before tonight's race.

It's heavy at 24lbs... but that's pretty much what I was expecting

Changed some build parts up, as usually happens...

Traitor Ruben frame/fork
600 crankset, with 115mm UN55 BB (as per Traitor's suggestion, but man... I have a ton of crank clearance. Not really convinced I needed to go square taper)
6500 group
Spyre mechanical with 160mm front and back
Kinlin rx240 rims on X9 hubs

Saddle is some gushy Serfas thing that came on another bike... its big and heavy, but I might just keep that sucker on there till I get my remounts down pat. All that gel is soft to land on

Rides good, brakes are kind of a PITA to get dialed in, but when they're dialed in they work good - rear fully locks up, seated, with road tires on dry pavement, so I guess I can't ask for much more than that

Bike FEELS slow af, but it's only 10lbs heavier than my road bike, and having been 10+lbs heavier myself last time I tried cross (and on a 21ishlbs bike), I'm just going to try to ignore the weight and focus on crushing.

Total out of pocket cost... stopped counting somewhere around $500... probably went over my $600 target cost, but it was well worth it to broaden my experience.