Disc Brake Conversion/Upgrade On Mountain Bike

I show the process of converting from V-Brakes to Disc Brakes on a mountain bike.
I bought this Specialized Rockhopper Comp a few years ago. It was in rough shape, but it had promise. What I liked about it was the frame & forks and had disc brake mounts, and the wheels were set up to mount disc brake rotors. It was screaming for this upgrade. I finally got around to doing it. The disc brake calipers I installed were Avid BB5’s. The rotors were 160mm.

Some people have asked me about the locking adjustable wrench I used in the video. The wrench is made by Craftsman:

Though there are other brands.


👍 And please give my video a thumbs up 👍





Hey viewers I picked up this bike a Couple years ago it was in really rough Shape I’m still working on it but one of The things that had jumped out at me was That it was a great candidate for an Upgrade to disc brakes let me show you What I mean First it’s got mounts for the disc brake Calipers both on the back And on the front Now having the mouse on the frame of the Fork is not that uncommon uh lots of Bikes will have them but if you don’t Have them then you might as well forget The upgrade it’s just not worthwhile but What made this a great candidate was the Wheels Both the wheels front and back were Already disc brake ready they have the Mounts here for the rotors this is Something you generally don’t see unless The brake already has disc brakes Um if you have the mounts but not the Wheels for the rotors you can buy a new Pair of wheels and you’ll be paying a 50 100 or more dollars uh for a pair of Wheels that are disc brake ready but This already had the wheels that are Just break ready so I’ve got the mouse I Got the wheels so all I need to do is Get the rotor and the calipers and get Everything all installed and so like I Said this is a perfect candidate to Upgrade to disc brake so I’m gonna go

Ahead and do that and I’m going to show You the whole process So I’m gonna start off by removing the Old v-brakes cables and housings the old Cables are junk and they’re too short And the housings are too short they’re Just not going to work but I’m gonna put Brand new cables and housings on there Anyway I mean if you’re going to spend The time and the money to upgrade to Disc brakes use new cables and housings Foreign [Music] Got that done So these are the rotors I’m going to use They’re 160 millimeter which is probably The most common size you can find them Bigger you know for like heavier Duty Like downhill mountain bikes and stuff But 160 is a good size so these ones I’m Going to use I want to clean them to get Any oil off of them and I’m wearing Gloves because even the uh oils from Your fingers can get on these and then Gets on the the pads and can degrade the Pads and I know a lot of people go oh Well I ride my bike through mud yeah That’s water water evaporates oil really Doesn’t it’ll get in the pads and just Stay there so what I’m gonna use to Clean them off is isopropyl alcohol you Can find this in the first aid section At your local grocery store usually or a Pharmacy drugstore and so this one we

Use and I use some paper towels here so I’m just going to go ahead and pour some On the paper towel and wipe these down Really well Uh if they’re brand new rotors these are Used rotors but you can get brand new Rotors a lot of times they’ll put oil on Them to uh keep them from uh rusting or Anything like that in you know in Storage and shipment stuff so Um you definitely want to clean those But even these used ones I want to clean Them just make sure that they’re nice And clean And just wipe them down and let them dry And they should be good Now I’m ready to install the rotors I’m Gonna start off on this wheel by Removing the skewer And then I’ll put it aside Again I’m using gloves to handle the Rotor now the rotors are direction we Want to make sure you install them the Correct way if there’s printing on the Rotor that generally faces out but you Can also look for arrows and the arrows Should be pointing in the direction of The rotation which uh with the side that The the rotor fits on should be pointing Counterclockwise so I’m going to go Ahead and set this into place and now You want to use uh screws that are Specifically made for mounting rotors They will generally be uh Torx head

Screws to fit like a T25 Torx driver so What I want to do is I’m going to start Screwing these screws in and I’m only Going to tighten them down to where I Start feeling resistance when it hits The rotor so when it kind of bottoms out I start feeling resistance go ahead and Stop right there because we’re going to Tighten them up more because we want to Torque them down to a a very specific Torque now that all six screws are in There kind of just tighten just a little Bit I want to go ahead and tighten them Down just a little bit more so I’m going To do this in a star pattern so I’m Going to go like one two three four five Six so just tighten this down a little Bit more Tighten this one down a little bit more Like that so now once they’re all tied In kind of by hand I’m gonna go ahead And use a torque wrench I’m going to use A beam style torque wrench with a T25 Torx socket on there and so again I’m Gonna still use that same star pattern But I’m going to go up in two steps I’m Gonna go uh up to 30 inch pounds and Then I’m gonna go around again it could Take up to 55 inch pounds 55 is inch Pounds is the most common uh torque Setting for rotors there are some rotors That use a different torque setting so Check yours but 55 is the most common so I’m going to take this up to

30 inch pounds [Laughter] And then I’m gonna go around again take Up to 55 inch pounds And they’re all torqued down to 55 inch Pounds Now that all the screws are torqued down To 55 inch pounds I’m gonna go ahead and Give it another wipe down with the Isopropyl alcohol just around the outer Edge of here where it the braking Surface of the rotor wipe that down And then I’m going to reinstall The skewer the lever should go on the Side of the wheel that the rotor is on And then just go ahead and do the other Wheel the exact same way as I did this One So now I want to go ahead and reinstall The wheels And you want to make sure that they’re Fully seated So to guarantee that the wheels are Fully seated in the dropouts what I’m Going to do is with the bike out of the Rack sitting on the ground I’m gonna go Ahead release the skewers and then clamp Them back in again Foreign Like that These are the calipers I’m going to be Using they’re Avid bb5s they’re a Mechanical caliper meaning mechanical Meaning that they use cables as opposed

To Hydraulics and they already come with The adapters made for the 160 millimeter Rotors there’s a 20 millimeter adapter For the rear and a zero millimeter Adapter for the front Um they’re nothing real fancy but They’re a solid little calipers I’ve Used them before I like them I’m going to start off by installing the Rear caliper first the first thing I Need to do is loosen these two bolts Here they go into the adapter these are Called CPS bolts and they’re a five Millimeter Uh bolt so I’m just going to loosen These a little bit these are used to Kind of adjust the angle of the caliper So I want them to a little bit loose So that way it can move around a little Bit and then this wheel here I want to Go ahead and turn this all the way Counterclockwise this is going to open Up the uh the brake pads in here Answered now I can go ahead and set this Over here Um there’s an arrow on the adapter here The arrow should be pointing in the uh Direction of the rotation of the wheel So this is it’s already on there it’s Already in the correct position so I can Slide this over The uh rotor like this and line up these Holes here with the adapter And then I can use the these other bolts

That came With there and get them all fitted in And they all cut they already came with Uh the Loctite pre-installed on there So that’s good so I get these in here And I’m gonna tighten these in And they’re also a five millimeter Hex fitting I’m gonna tighten these in But not clamp them down quite yet Foreign A little bit tight here and then I need To torque them down to about 80 to 90 Inch pounds And then I have my beam torque wrench Here and I’m going to take it up to About 80 to 90 inch pounds here [Music] Foreign There Now for the fork there’s a couple Different ways that the caliber could be Mounted one is is mounts similar to what Was on the rear of the frame and you’ll Use the zero millimeter uh adapter for Like a 160 millimeter rotor and it will Just bolt on the same way as it did in The back just like that The other method is post mount in which The caliper bolts directly to the fork Without the use of the adapter which is What this bike has I need to remove These little plugs here uh that are Protecting the threads

Like that So what I need to do is remove this Adapter here from the caliper but I want To leave all these little washers on There because I’m going to need those So Like that Now slide this over the rotor And slide this into place like this And start screwing these screws in And we don’t want to tighten them all The way down because we’re going to need To use these to adjust it later So leave it a little bit loose And I wanted to turn this little red Dial here fully counterclockwise an Earlier step and I forgot to do that but I can do that now so no big deal Like that okay so in the next step I’m Going to be uh cutting new housings and Stuff before I do that I want to go Ahead and screw these little Adjusters In so screw that little lock out there And what I’m going to do is I’m going to Line up these little slots here and then Screw this in and having the slots lined Up with the slot there is going to make It easier to install the cables Like that next I need to start cutting My cable housings I need a piece of Cable housing to go from here back to Here and long enough so that I can turn The handlebars without it getting bound Up so let me see figure out the routing

Here Um if I go from here And turn the handlebars and bring it Right back to about here And so that should be good so go ahead And cut the cable right here And then double check it And that looks like it will be good I Can even cut a little bit off maybe but We’ll see So now I need to cut a piece of cable to Go from here down along here to the Caliper and so I’m going to do is I’m Going to shove this into the little Cable stop there run this along down Here and run it down to the caliber here And I want to leave just a little bit Extra on there because I just in case I Need to trim a little bit off it’s Easier to trim a little bit off than it Is to add so I’ll cut that like that Now I clean up the ends of the housings Here you can see they’re a little uneven So it’ll just use this to kind of Clean these little bits up here So that they’re as flat as possible [Music] And do that on both sides Like that And then I’ll take a skewer and stick it Down in to open up the ends of the Linings in there so that the cable will Slide through smoothly Like that so now I’m going to install

The cable into the brake lever here so Put that in there slide that through This slot I got those slots lined up There so the cable goes in there and so Now I got my uh housing here I’m going To put a ferrule on the end of this Housing here like that and then I can Slide the cable Into the end of the housing And push it through And then get the cable housing seated in There like that So this Frame here the little holders Here are actually designed uh for like You know to adapt to a hydraulic uh Brake lines on here uh but since I’m not Doing hydraulic I’m doing cable there’s Like a little adapter here that fits in There that works as a cable stop in There so I’m going to slide this and It’s tight enough that I don’t need a Ferrule on this end of the cable because The cable housing fits like right in There nice and snuggly so I’ll slide That in there like that And then there’s also another little Adapter on this side so I’ll slide the Cable in through there And then I got the end of the cable here So I’m going to slide That into there and then push the cable In through there And I’m going to need a ferrule on this End of the cable housing where it goes

Into the barrel adjuster on the caliper So Slide the ferrule on there like this Push it on and then I’ll slide the cable Through like this and get this all Seated in there like that So now I want to take this cable and Slide it down through this like clamp Here And I’m going to pull the cable tight But I don’t want to have it the arm come Up at all I want to keep the arm fully Down but have the cable tight And then I’m going to go ahead and Tighten this little uh bolt here down on The cable Like that in this next step I’m going to Adjust the pads inside the caliber here What I’m going to do is I’m going to Take a T25 driver I’m going to stick it Inside this little screw here inside This red dial on the side there and I’m Going to push the caliper over And so what I’m going to do is I turn This Clockwise a pad is going to start to Come out from the side uh where the dial Is The pad will come up against the side of The rotor and what I want to do is I Want to adjust that pad out Until it pushes the rotor right into the Center of that slot When the pad is up against the rotor and This the rotor is right in the center of

That slot Then I’m done adjusting it Now they have the pads adjusted I need To tighten this down into place what I’m Going to do is I’m going to clamp the Hand brake down so that the it the pads Are clamped down on the rotor when I Have that done I’m going to go ahead and Tighten these CPS bolts Here and it’s a five millimeter Allen So just tighten these down And then that’ll lock the caliper in Place where it’s supposed to be And then I’m going to torque them down To about 70 to 90 inch pounds Thank you And then done with that so now when we Adjust this the inside pad was pushed up Against the inside of the rotor and it’s Rubbing a little bit and that’s to be Expected so what we’re going to do is We’re going to back off that inside pad Just a little bit so I have my T25 Driver here I’m just going to go ahead And turn this dial counterclockwise Just a little bit Until it turns freely And it’s not rubbing anymore just like That Now to finish this one up I’m going to Go ahead and trim off this cable here I have a little uh crimp end slide this Onto here like this and crimp it into Place

Now I’m gonna zip tie this cable into Place right here Foreign Like that And then I can use some nail clippers Here to clip that nice and flush And then I can just push this around Like that And to test it Works Okay so now I need to cut a piece of Cable housing for the front uh brake so How I’m going to Route this is from the Caliper come up to the back side of the Fork to the outside of the fork Bridge Here then go to the inside uh between The tubes there and then come up to the Brake lever here so I want a nice kind Of smooth curve out here go in there and Then come down to the caliper here and I Want to leave a little bit of extra Housing here to play with so I’ll go Ahead and cut it down here Okay clean up the ends of the cable this One looks pretty good It’s got like a little bit of Peace There Cut that off And then use the skewer to open up the Lining And then you skew it up the lining over Here Looks good So now I’ll install the brake cable here

Into the brake lever so I slide this in There go through this slot I have these Lined up down here And I turn those in like that And then I have the cable housing here I Want to put ferrules on to both ends of This one And then slide the cable through Get that seated in there And then route it down through here and Around behind there like that And then down through the barrel Adjuster in the Brake caliper like that then I can Loosen this little clamping screw down Here Slide the cable through Pull the cable tight And then tighten this little clamping Screw back down here again Making sure that the lever is not being Pulled up And I’m going to adjust the pads on this Caliper here so I’m going to rotate this Dial clockwise Until that uh pad comes over And the rotor is in the center of the Slot I think that’s about it there And something else that you also check To see if the pads are just right is try The brake lever if it bottoms out then It’s it’s too loose you should move the Pads in if there’s just not enough

Movement then it’s too tight you should Probably move the pad out but you should Have a nice good brake movement So now that I have the pads adjusted I Want to tighten the two CPS bolts that Hold the caliper to the fork so I’m Going to clamp the brake lever down and Then use a five millimeter Allen wrench To go ahead and tighten them down And then use my torque wrench to torque Them down to about 70 to 90 inch pounds Like that Okay so the inside brake pad is rubbing A little bit so I want to back that off And just do like a couple clicks one two Let me three Turn it I think it’s still a little bit Another click This seems pretty good but I’ll maybe One more You might have to play with this a Little bit just a little click and until You get it turning nice and smoothly That seems pretty good but I’ll maybe go One more click And if it rubs a little bit it’s not too Big of a deal because it’s going to wear Down pretty quickly and then it won’t be Rubbing So I think that works out pretty well Okay I want to trim the cable here And then put a crimp on on Right there

And crimp on the crimp on Like that Someone would zip tie the cable into Place so I’m gonna put one around the Lower uh Fork tube right here This kind of tightened down And I’m gonna put a zip tie up here on The fork Bridge Up here like this this will help keep The K the cable out of the way and away From the tire And then I’ll use some nail clippers to Cut these off Nice and flush Like that And then to test the brake And it works Now for a cosmetic purposes I’m going to Go ahead and remove these brake studs Off the forks they have flats on there So I’m pretty sure they’re removable now The best tool to remove these kind of Things is I like is a a clamping Adjustable wrench uh that these things If you try to use a regular uh flat you Know open end wrench on there A lot of Times they’ll just like uh round off Those Flats on there so anyway get this On here get this tightened down on there And then clamp it on And then Start unscrewing them They can be very tight There’s one

And there’s two Now to cover up these holes kind of Protect them in case they need to be Reused I bought these little plugs They’re uh M8 by 1.25 millimeter plugs And so just screw them in they’ve just Barely go in so I don’t want to go in Real tight because I don’t want to strip Them because they don’t go into too many Threads For just a little bit [Laughter] Like that and those will cover up the Holes Now I don’t think these rear uh studs Are removable so I got these like little Covers for them so just kind of press These over there like that I mean I Could always just cut these things off But I’ll leave these on there for right Now And done Um I think it’s a definite Improvement To the bike what do you guys think let Me know down in the comments uh this Bike was just screaming for this upgrade It had the mounts on the frame and the Fork it had the wheels already for the Rotors and I already had the parts here I have the rotors the calipers already Sitting around in boxes so it was just An obvious project and it was a lot of Fun so hopefully you guys found it Interesting as well if you found it this

Video useful and interesting click that Uh like button down there give the Thumbs up uh if you’re uh not to try my Channel click that subscribe button down There make sure you click the Bell so You get notified when new videos come Out I’m over on Facebook RJ the bike guy Go over there like that page over there I lost a lot of stuff over there anyway Thank you guys very much for watching

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