Painting a bicycle

Factual Questions
1

My son has a slight coordination problem, and still hasn’t learned to ride a bicycle, so I’m building a tandem for us to ride with him. I figure we get him used to riding on the back, then we can let him try the pilot seat, and when he can do that, he can try riding a bike on his own again. Anyway, since all the tandems I’ve looked at are upwards of $600, including used ones, I’ve located a frame in good shape for $45, and I’m planning on scouring Craigslist and garage sales until I fine a regular bike for cheap that I can scrap for the wheels, brakes, seat, pilot handlebars, gears, etc., and the few other things I need, like the second pedals and axle and gear set, and seat, I should be able to get on eBay or Craigslist, total budget will be about $175.

I’ve built bikes from scrap before, so I know what I’m doing, and I even already own specialized bike tools, like the axle tools, and the cable “fourth hand,” plus a full set of metric wrenches down to a 5mm, and a digital caliper. I have plenty of confidence in my ability to build the bike.

But I also want it to look good, and I’ve never painted a bike before. Does anyone here have experience painting a bike, who might be able to offer advice? Can I use auto paint? I haven’t seen specialty bike paint, other than touch-up paint. I own a dremel tool, and a drill with sander and buffer attachments, so I can get rid of small rust spots.

Do I need to sand off all the old paint, or just paint over it? Obviously, I’d prefer not to sand off the old paint, just because it’s a big job, but also because I’ll end up taking some of the metal off. There’s nothing really wrong with the current paint, except it’s gunpowder gray, and I want something that will show up better, like a bright primary color, or a shiny metallic color (or some combination); I even thought that if reflective paint exists, I’d use it for some kind of trim.

I have a little bit of experience painting military vehicles, but it was mostly sergeants saying “Spray that way.” I’m willing to try anything, though. Maybe there are even good Youtube videos someone can point me to.

I realize I’m asking for some advice, but my main question is really “What paint do I use?” and if that is all that gets answered, I’ll be happy; this is why I posted under GQ.

2

I think that in the long run, buying a complete bike will be much cheaper and a lot less hassle. BTW: I’m looking at tandems on Craigslist also, but haven’t found the right one yet.

I’ve painted one bike years ago. I sanded down the paint especially where there was any rust. Where I didn’t go down to the metal, I made sure that the old paint was roughed up some. Then I applied a coat of primer. Next I sprayed the frame with some Rustolem (spel?) from a can. I held the bike from a tree branch with a rope through the bottom bracket. It wasn’t the best job, but it certainly looked better than before and lasted a few years.

BTW: Putting a small rider, such as your son, in the pilot seat is a bad idea. It can throw off the balance of the bike and make it steer badly.

If you have an existing bike, have you considered something like a clip-on bike trailer?

https://stlouis.craigslist.org/bid/4998975073.html

3

I wonder if a small independent auto-body shop might be able to help you out.

4

I haven’t found one that doesn’t “need word” for under $450, and I’m sure any used bike needs some work. New bikes go for close to $1000, and used bikes from shops are all upwards of $600. The frame I found, which I checked really carefully with some tricks I know from working on engines, to look for cracks in the weld, and found none, and checks carefully for misalignment, and it was good, was $45. I already know that I can get a good parts bike for about $25. I bought a bike for $25 at a yard sale for myself, and I put about 6 hours of work into it, but only about $40, and it’s a great bike now-- I ride all over town (Indianapolis) on it.

All great advice, but what was the paint? automotive?

Well, he is 4’9, and 110lbs (yes, he’s 8, but he wears clothes from the teenage section of the store, and sometimes men’s small shirts; I know; he is huge. His doctor isn’t concerned, though, because his growth has been following a normal pattern, and slowed a little each year, and also, my husband was almost as big at the same age), and I am 5’5 and 150lbs. The front seat will have a quick-release so both my husband and I can ride it, and can adjust the height without needing a wrench, but if we try it and he has terrible trouble, we may give up the idea.

I wish we’d known about those four years ago. Right now, he is too big for one.

I am planning on putting 24" wheels on the bike. It can take 26", but I asked around, and it will be safe with 24", and I will be fine with the seat raised a little (I ride my 26" with the seat in the lowest position, because I have very short legs). If he still wants to ride it for fun, or we want to sell it, or he still hasn’t mastered the two-wheeler on his own when he is taller, we can switch it to 26".

5

I second this: these clip on trailors are also sometimes called “Tag Alongs”. I used one with both my kids. It’s a great way to learn to ride. It’s also a great way to do family bike rides at decent speed with a child who otherwise couldn’t keep up with a group.

They securely attach to the seat stem of the main (adult) bike. Thsi part is articulated, and detaches and reattaches easily for storage and transport of the tag-along, or use of the main bike independantly.

This is a great family solution. IMHO, well worth it even if you have to buy a main bike, too.

BTW- this does change the handling of the bike, so ride carefully, esp at first.

Lastly, although I’ve not taught my kids this way, when it does come time to teach independant riding without training wheels, I’ve heard wonderful things about the method where one removes the pedals and sets the seat low- the kid propels the bike by scooting the feet and safely gains a good sense of balance and steering.

6

I should add, this depends somewhat on the size and weight of the child and parent. The child needs to be significantly lighter than the adult.

7

Surely if you do this, the brakes will no longer line up with the rims? Unless you are planning to use disc brakes of course.

8

A few thoughts on the painting.

Preparation is king. Really careful prep of the existing paint is what will ensure a really good result. It needs to be rubbed down with wet and dry to a uniform perfectly smooth surface. Don’t imagine that the new paint will cover up any defects in the surface finish - it won’t. Even a slight scratch will come through. You may need to prime and cut any defects. A spray can of filling primer is good.

Years up years ago I helped and old g/f repaint a frame with auto paint. The result was OK, but using touch up cans was a seriously expensive way of doing it, and the results whilst OK were not stellar. Getting a good result with any sort of spraying requires experience. Even the slightest hesitation will lead to runs and a depressing result. Working around the more complex angles and joints in a frame won’t be trivial, and the potential for runs is great. At very disciplined wet on wet technique with very light coats may be the best answer. But practising on something else is going to help enormously.

It is probably worth talking to an auto repair place. You might find a friendly one that is prepared to spray the frame if you have done all the surface prep first. The trick is to find a time when they are spraying with a colour you want. If you want them to mix up a colour just for you it will increase the cost lots, but you may be able to cut a deal with them if they are repairing a car with a colour you like. Given the popularity of silver grey, you may be waiting a bit for something bright. I know this trick has worked for people in the past. A nice clear coat will make big difference too.

9

Just by the way, I believe typically tandems use extra-strong wheels, and extra brakes. You might want to check and make sure your parts are suitable for a tandem. Remember bicycles are not as over-engineered as military trucks; they’re as light as possible for their expected loads, so a double-load will be too much for a lot of parts.

I’m sure you can use Google yourself, but it never hurts to start with (the late) Sheldon Brown’s pages: to https://www.sheldonbrown.com/tandems.html
also a couple here, including building your own tandem crankset in detail: Bicycling Articles by John Allen and guests

10

I already read all of Sheldon Brown’s stuff. One advantage to using the 24" wheels is that I can use mountain bike wheels, which are sturdier-- I read his page on prepping a bike for slightly wider wheels, but this tandem frame already had fairly wide wheels, and the axles were pretty wide: it’s the taper that would be a problem if I used 26" mountain bike wheels. Also, I checked, and BMX side-pull calipers will work if they are adjusted all the way down, and they are pretty heavy duty, because they stop bikes going at high speeds.

I double-checked all this with a guy who has been building bicycle “choppers” for more than 20 years, as well as a guy who works at a bike shop, who is going to sell me the few parts I want to have new: the tires and tubes, and the calipers and cables.

Unfortunately, neither of them has much experience painting. The rebuild guy doesn’t paint except touch-up, because people who buy his bikes usually want to do some of their own customizing, and the guy who works at the shop doesn’t paint, because it isn’t something the shop does, and they sell only touch-up paint.

I dunno. Maybe I’ll try to figure out a design, like lightening bolts or flames, or even just stars, and get some Day-Glo touch-up paint and a stencil. Or I could even just put some stripes on it in primary colors. I’m mostly interested in visibility. Actually, designs on a gray background might be more eye-catching than a solid color. We don’t plan to ride on the street, mostly on paved biking trails, but some of them cross streets, and we’ll be traveling with other bikers, joggers, etc.

I really did look at those trailers, but he is way too big for them. You can’t raise the seat high enough: his knees would be in his ears. I wish I’d known about them when he was four.

11

I’d probably be satisfied with filling in any chips and scratches then sand them down and prime. You may want a more professional job. I know my spray painting skills are far from perfection so I would rather emphasis fun. Hardware store paint may outlive your interest in the bike.
Have you ever seen “The Muppet Movie” where they paint the Studebaker? You may be able to find the clip on Youtube since it is part of the “Can You Picture That” song.

12

As mentioned above, prep is key. When I repainted my 85 Bianchi MTB I sanded with 220/400 until all the rough spots were gone, and then two cots of primer and two coats of automotive paint (GM Quasar blue, which looks fantastic with the Celeste Green graphics). Getting an even coat is the real hassle because of the fact you’re painting a round surface and all the intersecting tubes. I used my air compressor and an hvlp gun, so if you have them you can save a bit. I suspended the frame with broomstick, sandbags,and an old rim so I could spin the frame around as needed. If you’re good with a rattlecan you can go that way as well although it won’t be quite as pretty up close.
Is there a powder coating place where you live? That would also be a really good option and not overly pricy ($100-200).

13

One other thought if you want quick and funky, you could try dipping the frame…

14

yes use car paint, if you do rub down any rust use a metal primer otherwise just rub it down to key the paint.

Tandem wise, i’ve built a couple out of wreckers and its pretty easy (and real fun to ride) In the past tandems have heaver duty wheels and even freewheels but now its usually standard mountain bike stuff that’s used (and i used the very cheapest parts and it was fine) One thing you really need to be aware of is tandems go fast and take some slowing down, (40mph is quite easy to get to!) and going down hill can be a fraught experience. So V brakes if you can and sturdy cables (saves stretch in the long run to the back) and a very good idea is a “drag brake” a separate brake that can be run from a friction leaver so one can put it on to slow downhill descents (usually they are drums) with speed being controlled with the hand brakes too.

Another thing, tandems can be more challenging to up up hill too, (not so easy to stand on the pedals) so it is usual but not really needed to have a very low gear fro hill starts.

Best bit of riding advice we got was “start on the flat” at first otherwise that first ride can seem impossible.

15

I’d imagine automotive paint would work just fine. Are there any custom motorcycle shops in your area? They’d probably know someone who paints their frames for them who would do a tandem bicycle.

16

Thanks for the advice, but we are probably not going to do much hilly riding. I was planning on doing a 5-speed, with the BMX caliper brakes front an back. We won’t be riding on the street, or anywhere where there will be any really steep hills. The bike shop I’m going to for the cables sells cables specifically for tandems, that cost a little more (not a lot, but brake cables aren’t a huge expense anyway), and are made out of some kind of combination fiber that is resistant to stretch.

I was figuring on riding the thing around a bit just by myself to get used to it, and then when my son and I start riding it, my husband will have to help us get started, maybe with a push, like when you are teaching someone to ride in the first place. The whole point is that it should be a little challenging for him, just easier than riding alone. He’s been trying to ride with training wheels, and can’t get the hand of it, and is getting discouraged, and at eight years old, doesn’t like being seen with them anymore. He also hasn’t built up the muscles to move onto a bigger bike, since he hasn’t gotten good at riding the little one with the training wheels he’s had for a while. I’m hoping he’ll enjoy this more. I know he’s excited about the idea of it.

I can ride my bike with him sitting on my carrier, so I think I have the balance for both of us.

I guess I have my answer that automotive paint will work-- thanks for the idea to use a coat of primer. However, I may just go with some bright stripes or trim the more I think about the difficulty of painting the whole thing. I just want it to be visible. Maybe some pin-striping from the auto store, plus something stenciled in bright colors.

I can upload a picture of it to the computer and try Photoshopping some different designs on it.

17

I started painting my bike a new color each summer when I was 11 so I’m sure you can do it. I just painted over each year but if you really want the best results have the frame sandblasted. I have recently done this with car parts and it shouldn’t cost much more than $25. Check for a local powder coating shop if you can’t find a sandblaster.

You can get good results with rattle can paints. Krylon is a decent brand and an epoxy paint will be the most durable. Pay attention to the cautions with expoxy paint though.

18

A few people mentioned powder coating. That’s what I would do. If you can get it down to bare metal, look into that option. A few years ago I had a Kitchen Aid mixer powder coated and it was only $60. I asked (for a friend) and car rims were only like $15 each. It’s really not that expensive. As long as your frame fits in their oven, I’d bet it’s less than $100.
You’ll probably want to bring it to them in a few smaller parts. Just remember that since the process adds a very small bit of thickness, make sure they mask off any holes that will have another piece sliding into it if there isn’t room for a little play.

If the parts are already painted, bring it to them ahead of time and ask if they can go over it. With my mixer, they went right over it. They could tell by looking at it that the original finish was powder coated, so it was find to go over it again. If it had been other types of paint, it would have melted. If it had an enamel finish on it, I think they said they could sandblast it for me.
Also (not that this isn’t obvious), you can’t sent it to them with anything non-mental. Any rubber bushings will melts, grease will drip off. Just the frame, nothing else. So you’ll be sending it to them fairly early in the process.

19

Right now it’s just the frame with a fender and two sets of handlebars, but there are LOTS of screw holes. I’m changing the pilot handlebars, and I will probable change the stem of the stoker handlebars, if I can’t get them adjusted satisfactorily. One thing I want to buy from eBay is a banana seat with the sissy bar it needs. I already measured, and it will work, and I think it will be “cool” for the boychik, in addition to being more comfortable. So, I probably won’t end up using the fender.

Right now, both sets of handlebars are “ape” bars-- the Stingray style, which can’t be the original bars. I want to drop them in the back at an angle, and I think they’ll work for the boychick, but in the front, I want to use either a straight bar (mountain bike style), or a BMX style. One of my two parts bikes has mountain bike bars, so I’ll probably use those. The other parts bike is incomplete, but it only cost $10, and it has gears, chain, pedals, and derailleur (the derailleur is broken on the otherwise complete parts bike). Altogether, the tandem frame, and the two parts bikes have cost me $95, so I’m not anxious to spend more than that on the paint job. I want it done right, but it’s more of a safety consideration-- making the bike visible-- than purely aesthetic, but I do appreciate all the advice, it’s given me plenty to think about.

I might post another thread in MPSIMS about bike restoration in general, but I got my “general answer” regarding using automotive paint, or Krylon.

Thanks to everyone who responded.

20

I understand that you don’t want to spend too much, just keep in mind that taking it to an auto body shop or getting it powder coated will mean that it’ll probably never get scratched or rust, ever. If you get it powder coated, even dropping it on the concrete will chip it, if anything (as opposed to scratching it down to the metal). If you spray paint it, you’ll have to make sure you touch up any spots that get scratched since they’ll begin to rust right away. I’m sure your frame, if it’s bare metal, shows signs of oxidation just from one day to the next.
At the very least, you’ll probably want to make sure you put a few coats on. Just watch your cost.
Also, just for kicks, you might want to at least ask a powder coating or body shop for a quote. You might find out it’s not that expensive. If one of those options is $50 or $60, it might be worth it to make it look nicer and hold up much better than $15 worth of spray paint.