Drilling chrome Handlebars

[Mike_H]

I've got an idea that involves running my control wires through the handlebars...problem is, I gotta make four holes to do so. Anyone know how to drill through the bars, w/o mucking up the surrounding chrome. I'm thinking duct tape, but I also think the chrome will flake after the edges are exposed. Any other thoughts?

P.S. this idea is actually for my warrior, but this forum is SO much better with the technical stuff. I think it comes from keeping 25 year old bikes on the road. Most of the guys on my warrior forum don't know how to change their own oil.

[havoc]

I've got an idea that involves running my control wires through the handlebars...problem is, I gotta make four holes to do so. Anyone know how to drill through the bars, w/o mucking up the surrounding chrome. I'm thinking duct tape, but I also think the chrome will flake after the edges are exposed. Any other thoughts?

P.S. this idea is actually for my warrior, but this forum is SO much better with the technical stuff. I think it comes from keeping 25 year old bikes on the road. Most of the guys on my warrior forum don't know how to change their own oil.

I'm not sure what the impact on the chrome would be. I've considered this on my project as well. Haven't made up my mind as yet; but, I'm not sure I like the idea of changing the controls after it's done. I am interested in what you find out though

[t3rmin]

Maybe coat the edges with a clear epoxy after drilling to stop it from flaking? Make sure your holes aren't so big they compromise the strength of the bars... It'd suck to have them bend under hard braking or something.

[8trackmind]

Use masking tape, and a Unibit. (step drill bit) The chrome shouldn't flake because the edge will be Chamfered somewhat by the Unibit.

[BlackStar]

From a fellow RSWarrior forum member, use a good sharp bit then paint the inside of the hole or use epoxy as mentioned above. I have found that a uni-bit usually raises a burr around the edge of the hole, which may actually be a good thing for the chrome not flaking, but not so good for running wires through.

[JHawkins]

when I drilled mine I used a small pilot hole and then finished with a nice sharp bit, went through like butter.

I have one of those spring loaded punches to make a dimple in the metal and they make getting the pilot hole in the correct spot a breeze.

[Mike_H]

Make sure your holes aren't so big they compromise the strength of the bars... It'd suck to have them bend under hard braking or something.

Definitely right about that. If I go through with it, I'll drill the holes 90 degrees from the bending axis (essentially drilling the in the same plane as the axis of rotation). This will minimize the stress around the hole...

[jtolbert]

I've never seen well-chromed parts flake. The cheap stuff tends to be the stuff that flakes. I guess it doesn't help much to say, "buy parts with good chrome," though.

[Zooks]

As a metal fabricator I would say - don't do it, bad plan, step away from the bike and put your hands on your head.
The handlebars carry an ENORMOUS amount of weight, particularly in an emergency. It is illegal to compromise (in any way) the steering wheel of a car, what makes your handle bars any different?

[Mike_H]

Well, they make handlebars with holes in them, predrilled. These are used for internal wire routing. I just don't wanna spend the 140 dollars, when I have bars that would work just fine for this, if I can get a hole through them. While I agree with Zooks in as much as drilling holes in bars all willie-nillie would be a bad idea, as long as I engineer the holes properly on my end (which I am very qualified to do) there shouldn't be any problem. I have not decided to do this yet, as it is a fair amount of work. I just asked about the first hurdle I would run into..

[beergood]

I think most decent handlebars are over-engineered
(unless you get into crazy weight saving race bars or exotic materials like carbon fiber). I've had a couple of accidental tip overs, and more often than not, the bars were able to take the force of the bike landing on them without bending. Also, steel tends to fail over time, not catastrophically, so you should see some fatigue cracks long before you find yourself holding a control that isn't attached to the rest of your bike.

I would follow the advice about using a pilot hole, a sharp bit and perhaps clean and touch up the hole to stop chrome from flaking.

And you are on a safe track with putting the hole at a lower stress point in the bar, away from a bend. Assuming you aren't drilling a crazy big hole.

Besides, if you are in a situation where you are going to be putting the bars to the limit of their elastic strength, I submit that you are already screwed. Kinda like making sure your seatbacks are up, your tray tables are folded up, and your seatbelt is snug, as you plunge into the ocean at 500mph

As a side story, two years ago a cousin of mine fell 50 feet straight down off a trail on his Honda 4-wheeler. A few pins in the right arm, and a thumb sewn back on and he was mostly fine. His bars (which are comparable) were bent forward, where he put most of his weight on them in the face first crash with the ground. So even with a little deflection, they were still stronger than a forearm and a thumb (which they found in his glove when they got to the hospital).

Of course, modify your bars at your own risk.

[argonsagas]

You already know the risks involved, and some good ideas on how to drill.

You could tape the area before drilling, but this would act against something you MUST do, which is to use a centre punch and mark the position for hole.

This gives the drill bit more metal surface to grip and cut, instead of allowing it to wander over the surface, and possibly damage the chrome.

Use a small bit for a pilot hole, then a larger one to suit your needs. Last, use a still larger one to chamfer the hole edge, but do this very lightly and use high speed.

I would use a tiny round file to smooth off the lower edges, as the drill bit tends to leave that area ragged when it penetrates.

Epoxy on the edge is a good idea, but it is awkward to use, whereas you could use lacquer and get the same effect. Borrow some clear nail polish for the job and you will find the little brush will allow you to get the liquid on both the top and bottom edges of the hole.