I want to do some cyclocross this fall and seeing as I have more junk than money I might as well try and build a bike. I set my budget at $150.
First off I dragged this late 80's/early 90's Specialized Crossroads home. It has a chromoly frame and canti brakes. And it has Shimano 100GS parts and 700C wheels. And a super funky suspension seat post.
I paid $50 for the bike.


So I stripped off pounds worth of junk in the kick stand, rear rack and fender.


The BB looks like it came from the Titanic. I am going to a cheap Shimano cartridge anyway so its no big loss.


Now the crank has decent gearing at 48/38/28 but it weighs a ton. I have a nice vintage Tourney GS crank that has the same gearing but I can't decide if I want to thrash this nice old touring crank on a cross bike. Hmmmm




Now the bar. Should I keep the riser stem or swap to an old shorter stem that I can raise? Should I be running the widest drop bar I have or keep it narrow? I want to use bar end shifters.
If anyone has done a similar build please feel free to offer any suggestions.

No meaningful suggestions, but I like the idea. I happened to see a very similar (?something)Cross in my mother-in-law's garage this weekend, but it looks almost new except for rotted tires.
Make sure you keep the thread updated with how it goes! I'm starting to get curious about CX myself; maybe next year after I get some level of fitness back...
About the crank, are those steel chainrings? That would probably save some lbs right there.

Find someone with a Trek 520 set up for cyclocross and copy whatever they did.
Around here, it's the frame of choice for that...

That's a good find for that purpose. Pull the 48 off the GS crank and use that. Some guys would also get rid of the 28 and front derailleur and just run 38 + rear gears. Single front ring is getting pretty popular and around here (midwest) where you see fronts between 38-42. You'll get style points for using a crappy crank on your race bike.

Stem and bars are personal preference depending on how you ride, but I would start by copying your road position. Many ride cross entirely up on the lever hoods. I move between hoods and drops regularly. Put new brake pads on and you'll be ready.

I like that idea of pulling the big ring off. I don't know if its possible but I am going to have a look at that. I may ditch the entire bar and stem and use the widest bar I have with a short 60mm stem that has a lot of rise.

The cheap 100 GS crank does not come apart. To Bad.
I could cut the big wheel off but that is even a bit to hillbilly for me. So I installed a cheap Shimano sealed BB and put it back together. The beater looks nasty and that crank is like a boat anchor.


The cassette is hardly worn. But now that I find the original tires still on the bike I guess thats why. The pulleys on the RD were like new under mounds of crap. The cassette is 13-30 so that's decent gearing.


The rear bearing races and cones were in excellent shape. I was worried when the skewer was rusty but all is good to go in these early "sealed" units.

So is this a hybrid that your converting to cyclocross? That is sweet, keep us posted.

I think you will want a road stem. I tried something similar once... put drop bars on my mountain bike when I converted it to a commuter. I found the position on the drops to be extremely stretched out. A shorter reach on the stem will probably feel better with the drop bars. YMMV

You might consider cutting/grinding the teeth off the 48 chainring, just leaving it in place as a outer guard. You shouln't need the inner 28 ring, if you are on hills/conditions steep enough to warrant using the 28 then faster to get off and run.

I am having trouble deciding on the stem length. With the original bars stem length wasn't an issue but with drop bars the hoods are a long reach. The top tube is a bit longer than my other bikes of similar size but only by 7-13mm.
I swapped in a short stem with lots of rise. It sharpened the feel considerably and made the reach feel better for off-road conditions. Does it look goofy? I guess thats a moot point because the bike does look a bit awkward.
So I took it for a spin without brakes and it rides very nicely. Doesn't feel like a race bike though.
Here is where I am so far. Seat post about 1 cm lower than I usually ride and the bars up high.


I want to use these old 105 aero levers but I need to figure out how to hook up the front brake without the bar stop it had with the old bars.
And I got 2 nearly new Ritchie cross tires from a buddy for $20. 700x32C


I am going to tuck the cables in but I could till run them out the top. Would they bind with such an extreme bend?

I don't have any pictures right now...but I did a VERY similar build on a Cross Roads. I was planning to use it as a beginner cross bike myself but the frame was a little small so I ended up giving it to my girlfriend. I was looking for a Cross Roads (or similar) in my size but came across a good deal on a proper cross bike so I went with that.

Your builds looks pretty good. Try it out...if you find you want something lighter/different then adapt accordingly.

Here's a pic of my Cross bike (05? Raleigh Team Cross) just because. It's a Raleigh and wears a Brooks Pro...sounds vintage even if it doesn't look the part

I notice your bike has a triple. I won't feel so bad running a triple then.
I want to do a few races before I dive into the deep end. I'm not going to win any but I want to have some fun and its a good way to extend the season.
After riding it for a bit I can already see the bike would be ideal for riding around campgrounds or on the gravel roads that surround my small town. The long wheel base steers slow but seems very stable.
I want to get it done tonight if time permits.

Finished it up tonight and took it for a 15km gravel road ride. Over all it works very well. Its so stable I can ride with no hands and watch the bar move around finding its line. Must be all that rake in this long wheelbase.
The only thing I didn't like was the bars. They feel narrow compared to my newer bikes even though they are wider than whats on my Marinoni.
Lots of mud clearance but the bottle got so dirty I couldn't drink from it anyway. I don't even know if cross racers use bottles.


Must be 1.5 inches of clearance between the fork and the tire.
Rear brake is now on the left, have to remember that! And the bar end shifters are left with a little "give" so they don't bust off in a crash. Brakes are also set up a bit soft.

Looks awesome! I always wonder why more people don't use these old hybrids as cross bikes. I guess changing out bars is maybe beyond what most people want to do.

Personally, I would put the largest tires I could fit on there.

The bike came with 700x38 and I was planning on 700x35 but these used tires were so cheap I couldn't pass them up. And these 700x32 tires are as big as the 700x35's on my Sherpa for some reason.
I can't wait to race it next week. I can see the other riders faces already.
Here we go again.....

Nice conversion! That top tube does look awfully long. Might be the angle of the shot. IIRC, the 100GS and 200GS cranks are steel crank arms covered in plastic. That's why it feels like a boat anchor.

I hope to build a cross style bike out of a Diamondback mtb rigid frame some day. Very similar config, a Suntour XCE triple, 8-spd shimano ultegra bar-ends, and Tektro aero brake levers.

that bike looks way fun to ride! good job

I really like it. Well done. MTB's are usually only good for one thing as they are setup -- off pavement. On pavement they ride like pigs. However, when tricked out, they make good commuters, trail bikes, tourers, etc. I have tricked out a few, including, years ago, a rigid fork Specialized Rockhopper with an elliptical Scott aero MTB bar and 32mm Avocet Cross tires. It was a bullet proof ride almost anything bike. Change in tires alone increased average speed by 3 mph. And, the ability to get in a semi aero tuck meant I could build up some speed on pavement. I strapped it to the top of my car for a 7 week vacation (a grace period I allowed myself between jobs) across the country to Ocracoke where I rode the hell out of it on the Islands.

I have an old Fisher Procaliber I might have to experiment with.

Frankenbike thread coming.

very nice build, thinking about doing the same to my schwinn crosscut. And what year is your fj40? me and my dad love them to death, heres a pic of the '78

The 40 is a 76'. Its the cyclocross version of a 4 seat vehicle.

Awesome build! I'm working on building a singlespeed 'cross frame for myself.

Looks great! Have fun in the race!

No need for a bottle as cross races are so short. + they get in the way when you shoulder the bike.

No that you need to... but if you remove or cover the decals, hardly anybody would notice that it started its life as a hybrid.

Here is the one I built. Originally destined as a starter cross bike but was too small so I repurposed it as a commuter for my girlfriend.

Very nice build, ricohman! Enjoy!

how is the length on that? WIth a saddle height that low I would imagine the reach is pretty long?