tenors

I've decided to post progress of my rebuilding / conversion of a mid 90s Specialized Rockhopper into a functional city bike. This is a work-in-progress, and over the course of the next months (years?) I hope to learn a lot about building bikes. For this reason, I invite any comments or criticisms of an aesthetic, functional or personal nature.

First thing's first - what do I mean "city bike"?

• I want a really comfortable bike that isn't afraid of bad roads
• I want a decently fast bike with gearing similar to a road bike
• I want it to look cool but also undesirable - not a problem since my taste is contrarian by nature
• Some racks would be cool

It seems to me that an old school mountain bike is ideal for this purpose. I live in Austin, and so my first move was to get an old Rockhopper frame from Yellow Bike Project. It has a long, road like geometry which I thought would suit me (top tube is c. 24"). It is not without problems, however:

• No fork! No idea what sort of fork I need!
• Slight rust in BB, dropouts, steerer tube!

My first step was to address the rust. I used naval jelly, toothbrushes and wire brushes to get the rust out of all the threaded areas. This stuff worked great, and I highly recommend it. The bottom bracket is now decently clean, as is the head tube.

Next, I decided to strip the paint. I used aircraft stripper, which didn't work that great. However, in the process of doing this, I noticed that the combination of gray paint, black primer and bare metal looked pretty cool. So - I decided to leave it semi-stripped, wet-sanding the frame with 400-600 grit and some steel wool.

I especially liked the brass-color of the brazed-on bits. Picking up on this, I added some gold leaf chevrons to various parts of the frame.




Note that the reddish-colored metal on the frame is not rust, but rather some copper colored paint I rubbed on the finish in different places.

Since there is now a lot of exposed metal and relatively fragile gold leaf, my next step will be to clear coat the frame quite heavily with Rustoleum "Stops Rust" enamel. I will probably then knock the shine off of it with some steel wool, to maintain a more metallic looking finish.

tenors

Addressing the mechanical side of things - issues I am still working out in my mind
Fork
Since I don't know what year this Rockhopper was (serial number is not helpful), I am unable to determine whether it had a rigid fork or a suspension fork. In addition, if it did have a rigid fork, it may indeed have been one corrected for suspension travel. I plan on going back to YBP and putting the bike on some 26" wheels, substituting different forks until I get a geometry that makes sense to me. I suspect that an 80mm-travel adjusted fork is what I will end up with.

Headset
YBP probably has the tools I need to install any sort of headset. Obviously I can go threaded or threadless - the former being more 'authentic', but presenting some difficulty in fork allocation, since threaded 1 1/8" forks are somewhat rare. I prefer the look of quill stems, but there may be technical disadvantages to this route.

Bottom Bracket area
This part of the bike will probably present the most problems. I know from this site that these bikes had cranks with 48T rings, which seems sufficient for fast gearing given a 11T-12T cassette. However, being very new to this process, I am really at a loss as to what crank to buy - should I get a (cheap) old crank, or a (cheap) new crank? JIS or ISIS or what have you? The downtube is around 31mm in diameter, and the BB is 73mm - pretty standard. I understand how all the parts work together to produce a straight chainline, but I am sort of bewildered as to the order of operations needed to accomplish this. I will probably start with a JIS crank I like and work backwards from there.

Drive train in general
I like grip-shifts, which seem to necessitate some kind of 1:1 pull ratio SRAM derailleur. However, I am not sure how many speeds I will go ahead with. I am leaning towards an 8 speed set up with SRAM x5 components.

Economically sourced parts
I am fortunate to have access to a local charity that provides bike parts for either a small monetary donation or time spent volunteering. I am trying to build this bike as cheaply as possible, but I am not sure which parts are worth spending a little money on. I am thinking I could get a good second hand v-brake system there, but I am reluctant to use second-hand shifters. New cranks are expensive, so I hope I can find something workable there.

Wheels are another issue - I don't know anything about them. I'm attracted to the bargain wheelsets (around $100) sold by Nashbar or Jenson USA, but they have aero spokes and obnoxious decals.

There are, of course, a hundred other issues to be dealt with, but these are the ones most prominent in my mind.

BCRider

Instead of a spray on clear I'd suggest using the oil based version of satin Varathane. Put on two coats with a brush but thin the varnish slightly with mineral spirits. The thinning combined with a nice brush will let the varnish lay flat as you could wish for and the satin sheen will achieve the look you're after while hiding any dust specs that occur. Apply to or three coats and allow to dry for a week before starting to assemble. After a week the varnish will be tough enough to withstand most abuse. It'll continue to harden over the following two weeks even more. And it's pretty tough stuff when fully hard.


With the chain stays level you sould be able to measure up a pretty close approximation of the fork length needed for an axle to crown measurement. Align the tape measure or yardstick with the steering head angle and see where the axis touches the floor. Allow a few mm's for the headset cup and the axle rise from the tip of the dropouts and you've got a number to go shopping with.

And if you can look up how to "antique" that gold paint you applied. I like the look but it's too garish as it sits right now. An antiqued treatment of it to tone down the bightness a little would make it blend in far better and be more in line with the distressed junk yard dog look you're after.

Also keep in mind that you may be starting a whole new trend of funky looking high end "distressed" bike frame finishes. As such you may be developing your own theft risk...

tenors

Hey BC rider, thanks for the tips. I took the measurement you suggested, which gave me roughly 19.5", or 495mm.

Looking at some rigid forks from around the internet, I get axle-crown lengths of
Tange - 394
Dimension - 410
Dimension - 395
Surly - 413
Salsa - 425

I noticed that when the chainstays were level with the ground, the top tube angled up a bit more than is typical with the 90's Rockhoppers that I have seen. When I tilt the top tube down to a more conservative angle, it takes about an inch off the measurement in question, giving me 469mm.

I was expecting to have to use a short fork on this bike, but there is almost a 3" difference in the axle-crown measurement of the short Dimension fork I found and the measurement I took, I believe I have to look into longer forks to achieve something close to reasonable geometry. Long story short - I am going to have to test a bunch of forks out.

As for the finish, the gold is meant to be a bit garish - in fact I may clean the edges on it by spraying a 5mm line of white on some of the gold edges. We'll see. I appreciate the tip about the Varathane, but the Rustoleum enamel seems more suitable given its rust-stopping properties. I think it will look pretty good after it hardens up and is steel-wooled.

**edit**
Scratch that, did another visualization. 395mm fork actually gives a gentle rising top tube, just as hoped.

Mondoman

Frame:

I like your look, too. Before you start assembling anything, treat the inside of the whole frame with JP Weigle Frame Saver, especially as you've had some rust issues.

Crankset and BB:

I like decent quality (replaceable rings is an indicator) w/pins and ramps, and steel rings for durability.
Here's a truvativ 48t one at a good price: $34 before shipping
https://www.outsideoutfitters.com/ps-...-crankset.aspx

It uses the powerspline BB, which is cheap but has some advantages as a splined system.
$14 before shipping for 73mm, choose either 113mm or 118mm for your chainline:
https://www.outsideoutfitters.com/p-5...m-bracket.aspx

Cassette:

I'd choose an 8-speed as cheaper and more robust than 9 speed, but with an extra gear over 7 speed.
SRAM and Shimano are the good quality ones, and SRAM's PG-830 will run you $13 before shipping here:
https://www.blueskycycling.com/view_product.php?pid=947 (pick 11t-28t, 11t-30t or 11t-32t)

Chain:

Again, SRAM and Shimano are the big ones, with SRAM you get an included reusable master link, so I'd go with:
Less than $9 before shipping for PC-830 here: https://www.speedgoat.com/Catalog.aspx/Browse?Prod=8547

Brakes:

Your V-brake strategy sounds fine, but also consider that you can find new cartridge-pad Shimano V brakes for $14 each before shipping:
https://www.bikesomewhere.com/bikesom.../18/4300/41928

Make sure your brake levers have the pull ratio for V brakes (linear pull brakes), not for the older cantilever brakes.

Shifters:

I also like grip shifters. SRAM has certain models that have the Shimano pull ratio, and are used with Shimano RD's. I find the cheaper Shimano RD's to be more robust than the cheaper SRAMs.
The MRX are the low-end models; you can get an 8-speed rear and a "micro" front for about $20 total before shipping here:
https://www.jensonusa.com/store/produ...x?SSAID=189896
or here: https://www.rei.com/product/737409
or here: https://www.niagaracycle.com/product_...oducts_id=4997
The "Attack" line are higher end grip shifters with Shimano-compatible pull ratio on rear, but cost roughly double.

Front Derailleur:

This Shimano LX looks good, as long as you have a 1 1/4 or 1 3/8 seat tube:
$16 before shipping. https://www.cambriabike.com/shopexd.asp?id=91007

Rear Derailleur:

Here's a Shimano long-cage rear derailleur for $21 before shipping:
https://directbicycleparts.com/page.c...ils&sku=RD8792
I tend to think that the Shimano metal cages are more robust than the SRAM plastic ones on the lower end.

Wheels:

Don't skimp on these. They will be absorbing the shocks and bumps, and you want them to be robust.
Skip the el cheapos. I've been happy with wheelsets with Rhyno Lite (heavy-duty!) rims and Shimano XT hubs:
$150 for the wheelset (you'll need rim tape, too): https://www.jensonusa.com/store/produ...+Wheelset.aspx

fietsbob

If there is a Head tube for 1" forks , it increases the likelihood it was a rigid fork, , tig joints puts it in the could be either lands.

garage sale GT

Aren't you supposed to heat the gold leaf so it melts onto the metal?

Member Miamijim posts on here & especially c&v a lot. He's got a photo of a gold leafed Peugeot fork. I think THAT'S how it should look!

tenors

A couple of quick points: no, gold leaf isn't heated to stick to anything. To use gold leaf, you basically spray glue onto a masked off area, then smoosh the leaf onto it. After a bit of burnishing and brushing, it sticks to that area pretty precisely.

Also I forgot to mention that I need a 1 1/8" fork. That limits my options a bit.

Big thanks to Mondoman for his help. The argument for an 8 speed system is pretty strong I think, and that crank looks fantastic for the money. My only worry is your recommendation of 113 or 118 spindle...that seems like a pretty big difference. Replaceable chain-rings is a big plus, though, and most cheaper cranks do not offer that.

tenors

Also, I forum member was kind enough to PM me and offer some wheels for the build. Unfortunately, I cannot respond as I don't have 50 posts yet. I left a message on your user page, though, with my email address.

fietsbob

Well the piece at a time approach is a long road.. You may find a short suspension corrected fork in threadless.
whether you like the Trail that results from putting that fork on there is a separate issue,

Bikelist,org crowd goes on and on and on about high trail and low trail, front loading /rear loading/
porteur/Randoneer, francophillic necropsy of old builders, , flop, plane ing ..
and all sort of esoteric stuff that the publisher of BQ
makes his business out of writing about.

and the young flush with cash computer programmers buy.

BCRider

Well since 1 1/8 is the standard these days you should be able to find lots of options.

You did take away a bit to allow for the headset cup and the height of your axle above the ground when you measured? 495mm seems like it is very long. My 100mm travel suspension fork only has an axle to crown of 500mm. So I suspect that you didn't allow for the axle or perhaps the axle and headset cup but instead just measured right to the floor.

I just checked my very old school bike that originally came with a rigid fork and has a very old school nearly horizontal top tube. The axle to crown for it is 415mm. And as I say it is very obviously more old school by far than your frame. So to make your frame sit properly I suspect you're looking for something more in a 430 to 450 mm A-C length. There are Kona Project 2 forks on Ebay when I checked that are 440mm long that I suspect would be a nice fit for your frame. And the "look" would certainly be there with those once you distress them the same way.

Going back to the coating. Using anything abrasive to flat out the shine means you're risking the chance of going thru the coating at some points such as around edges. It's pretty hard to remove the shine from inside corners without working the material around it too much and going through the coating. If you want a flat or low shine finish I seriously recomend using a product that produces that sort of finish in the first place. Not to mention that it would be a lot of work to properly remove all the shine in all the nooks and crannies of a bike frame. All in all you'd still have some glossy spots as well as likely some spots that develop rust blooms later on. Just go with a low sheen product in the first place and be done with it.

531phile 

Better get rid of that gold leaf, some thug might think that is real gold and want it for his teeth.

tenors

BCRider, thanks again for the tips. I will look into another finish, or at least do a test of the enamel before I do the whole bike. I don't think I risk going through the finish if I use steel wool, it tends not to abrade unevenly like sandpaper can. I will look for the stuff you recommended and give it a shot.

I do think I futzed the measurements - I did another visualization yesterday using my floorboards as a guide, and got results similar to yours. Before I buy a new fork I am going to test a couple out, probably on monday.

tenors

OK mini update: BC rider turns out I had some Varathane at hand. I thinned it out a bit and it appears to be working quite well. We will see what the satin finish looks like.

Here are some pictures of the process:

Mondoman

Regarding your questions about the BB spindle length:
Remember, the 113 vs 118 is total length, so actual chainline diff is 1/2, or 2.5mm. The crank entry mentions: "113/118mm for 48.5/51mm chainline".
Sheldon's article on chainline is here: https://www.sheldonbrown.com/chainline.html Based on that, and since you'll probably be using the 48t a lot more than the 28t, the 113mm spindle for a 48.5mm chainline is probably what I'd choose.

BCRider

When it's "free" it's always worth trying it out. I'm pretty darn sure you'll like it but be sure to let us know how it works out. Remember that any paint or varnish will continue to harden and become tougher over about a two week period. So don't stick a fingernail into it the next day, see a mark and give up right away. This stuff was good enough for bowling alleys at one time before the two part catylized finishes. So you know it has to be pretty decent.

tenors

Oh I get it now - thanks for the clarification. I had read Sheldon's page before but the topic is a little unclear to me still.

tenors

OK a quick update is due -

Firstly
The finish is going quite well. Sometime around Wednesday the finish will hopefully be hard enough for a slight sanding and buffing out with steel wool. Despite saying "Satin" on the can, the stuff I used is very very glossy.

Secondly
I went down to my local bike co-op and looked for some parts. I thought that I could find some brakes, and maybe a fork that hadn't been cut down too short for me, but I was resigned to having to buy derailleurs and cranks new. I was completely mistaken - there weren't any v-brakes, but there were other parts:

1. My fork. Not a fork that fits, but I found the original fork for my bike - same color, and the painted part of the steer tube is the same length as the tube on my bike. Not bad, right? It's a very light tange chromoly fork with cantilever bosses as you would imagine.

2. Rear Derailleur - I saw some nice shimano derailleurs, but I decided on a sram x7. This locks me down to grip shifters of course. One problem with it is that there does not appear to be a barrel adjuster, or threads for one. I am not sure if this is going to be a problem, but I may be able to find one I can drop in.

3. Front Derailleur - Shimano XTR, circa 1995. Not much to say about it, but it seems nicely made.

4. Crankset - a bit rusty, a bit janky, a bit old, but still cool - Shimano Exage, with Biopace chainrings. 48T on top. I will probably get some replacement chainrings.

The price? It is donation based, so I gave them 40 bucks. This is great news for the budgetary side of things, because I was about to spend more than that on the fork alone, and probably 60 on derailleurs and 60 for a crank of some kind.

mobaar

SRAM makes trigger shifters too, so you're not locked to grip shift if you prefer triggers.

surreal

are you gonna run cantis or Vbrakes? I can probably toss some cane creek cantis in the box with the wheels without significantly affecting weight. you'll need to find shortpull levers and cable guides, though. I like v-brakes more, which is why i have unused cantis lying around.

-rob

ps-it's awesome that you found the original fork. scores style points, takes all the geometry guesswork out of the equation.

531phile 

SRAM makes trigger style shifters too and grip shifters also usually come with big oval plastic barrel adjusters.

tenors

First surreal/rob- thanks for the offer. I am pretty sure I am going with V-brakes, though, seems easier/neater to set up. The bike originally came with v's too - however if you want to get rid of them, I can donate them.

also - thanks for pointing out that SRAM makes ESP trigger shifters. I think I'm going to find some NOS 8-speed x7 shifters if available though, they're the only type I can use that are all-black and decent looking.

I have to say I really like the integrated brake/trigger shifters that shimano makes, I would be tempted to use something similar of SRAM made them, but they don't seem to make anything comparable.

Wordbiker

Be thankful they don't. They may seem like an elegant solution, but the necessity to replace the whole unit once the shift mechanism gives out kills the appeal for me.

tenors

OK, here are the rest of the components (almost)
SRAM x.7 Gripshifts, 8x3 Speed
SRAM pc830 Chain
SRAM pg830 Cassette, 11-30
Tektro 839 V-brakes
Avid fr-5 Levers
Geax Roadster Tires, 1.5x26
Shimano UN-26 BB, 73x122
Round Cork Grips

Will put some progress pictures up soon. Things are moving along!

tenors

OK - more parts have been purchased. This is prettttty much everything.

1. Headset. I got a silver FSA pig.
2. Cables - Jagwire Hyper (Gray)
3. Another crank - for about 18 dollars I picked up an 48T Acera - it should fit my BB perfectly, and it should index better than the biopace.

Today I received the parts I ordered before. I have installed the brakes - silver looks okay.

One thing I am concerned about is the handlebar setup:

With those grips I have 8.5" worth of stuff on the bar (216mm). I can trim the cork grips down quite a bit, say an inch, which would bring me down to 190mm - but this is still pretty long, and I wanted to use non-mountainbike type handlebars. I wanted to use a North-Road type setup. Hopefully I can find a handlebar which will fit all that stuff.