All right, so not so long ago I wrote about performing a valve adjustment on my motorcycle and oil changes on both that and my wife’s car. This is all within the last year, and for someone who has never performed any mechanical maintenance beyond filling power steering fluid prior to that, I feel I’m allowed to be a little impressed with myself.
The first time I changed the oil in the wife’s car, it was something like a 7 hour job. Like I said, not mechanically experienced. Once the weather warmed up a bit, I changed oil and filter on both the car and the bike in around 6 hours. Hardly professional mechanic level, but I was bolstered by it.
As an aside, prior to changing the oil on a motorcycle, you’re supposed to take it on a short ride to get the oil flowing. So I did that, and discovered that while the bike will start at 28 degrees, my gear is not good enough to actually ride at that temperature. In particular, I need different gloves for winter and some manner of neck warmer. I also got to find out what cold tires mean. No harm done.
Emboldened by my success with the oil change, I began to look into a brake problem I’d been having. I would get an occasional pulsating when depressing the brakes gently, usually from a fairly low speed. I started by hoping it would go away, but instead it got worse. So I looked it up, and it’s an issue caused by a warped brake rotor.
Now here’s where things start to balloon. See, a motorcycle rotor is too thin to safely machine flat, so it has to be replaced. When replacing the rotor, you should replace the brake pads as well. As I’m checking the manual and the walkthrough at ninja250.org, I see the mention of a possibility of having to replace the brake fluid, and figure I might as well do that while I’m at it. That leads me to checking the service schedule in my Haynes manual and seeing that the rubber brake lines themselves are supposed to be replaced every four years. This bike is from 2002, and I’m pretty sure those lines are original. Yeah, time to replace those, and while I’m at it I can make the upgrade to braided stainless steel brake lines for roughly the cost of questionable eBay new-old-stock parts.
So what I thought was going to be a fairly small job had grown somewhat. No matter: everything finally came in the mail, I have a Sunday set aside, and off I go. I started with draining the brake fluid. Did you know that DOT-4 brake fluid is clear? Because what was in the sight glass on the handlebar was yellow, but I put that to aged plastic. That plastic was fine: what drained out of the lines & reservoir was something between generic American beer and piss-weak office coffee in color once it was in the bottle. Hmm.
But I disconnected everything, took the wheel off, and got the old rotor off with several soaks of WD40, some swearing, and almost breaking a loaner Allen wrench. I’d forgotten those are put on there with thread-locker, in spite of my having actually bought some to put the new one on. Eh, go me. I get the old pads out of the caliper as well, and put the new ones in. This presents some trouble, and once they are in, they’re almost touching. That’s a problem, they’re supposed to be able to have that rotor in between them and then some, and I can’t even shove the old rotor in there. The new one’s even thicker than stock.
When all else fails, either lubricate or clean and hope something comes up. This is where my wife abandons her duty of moral support/mockery and bails; brake cleaner smell was a bit much for her. Fair enough, though I’ll admit to liking the smell.
Now I’m cleaning the caliper and having some trouble. See, there are two posts that shove the brake pad against the rotor, with the other pad as a backer. I can only get one post to move, the other one is stuck out a good half centimeter. The one won’t come out, the other won’t move a bit. Repeated soakings and scrapings do nothing, and I’m starting to get frustrated enough that my hands are shaking. So I take a research break.
Apparently the trick is to blow them out with an air compressor. But carefully. Ya huh. So I wrap the whole thing as best I can, stick the compressor nozzle in the hole where the hose end was and BLAM! Only the moving post came out. Great. So I make a shim out of a paint stir stick to hold the now-free post in its place just enough to maintain pressure, wrap everything, and hit it again. Success! In this case, success means I get to scrape dried brake whatsit off everything with a screwdriver. Satisfying, though.
I put everything back together and this time it fits with some room to spare. Plus, you know, the entire brake should work now. The brake line replacement itself was no big deal, just paying attention to torque values. Putting the front wheel on was its own ordeal, but not an entertaining one; there are some tabs that have to line up from the wheel to the speedometer hub that are identical to some other tabs that are a 90 degree angle from them. When you line up the wrong ones and tighten the front axle at all, the front wheel locks up. I got the wrong ones four times in a row and freaked out a little. Also filling & bleeding the new brake lines took longer than I’d expected until I realized I was also having to fill every cavity on the caliper, duh.
But I’m finally on the home stretch. Everything is going well right up until I go to put the correct amount of torque on the front axle and realize that the torque wrench is 3/8″. The socket is 1/2″. Also this wrench doesn’t even get close to the 88 newton-meters the book says I need for this. I’d just go to the store and get one, but torque wrenches are expensive and it’s past 11:00 PM, everything has been closed for a good while, and I’d been at this for nearly 12 hours. Did a walkaround for the torque values I could complete, cleaned up the work space, put the bike away and went home.
I managed to borrow an appropriate-to-the-task torque wrench from a friend of a friend and yesterday I was able to tighten the front axle, put in the cotter pin and take it out for the first proper ride since … last September, I think.
Was an interesting ride. Aside from the usual post-mechanical “oh man, what if I messed something up and it spews fluid all over everything and I die” tension, there’s the addition of bedding in the new brake pads to the new rotor. See, the rotor is machined flat, and to get grip the pads have to scratch the hell out of it, which they’ll do in their own way that is unique to this bike, how the caliper is resting, and a bunch of other voodoo I don’t understand. So it’s a process, and for the first 300 miles the brakes are of questionable utility. You start out at a walk and check them, then at a jog and check them, then you actually start the bike and check the brakes very gradually and at low speeds, slowly building up.
I went on a fairly leisurely 30 mile ride, going easy and avoiding the freeway. I’d forgotten how fast a bike feels, even at low speeds. Feel for it comes back fairly quickly, even if I did kill the bike at a stoplight. My nose itches? I’ll just lift the visor with my left hand and hey why’d the bike die?
All that and I completely forgot to replace the old, grody brake fluid in the rear lines. Ah well, that can wait. I don’t much use the rear lines anyhow.
P.S. I’m quite pleased so far, so I should probably call them out: Venhill Stainless Steel Braided Brake Line and Galfer HH Sintered Metal Pads and Wave Rotor. And a Pitbull stand to hold the bike up with the front wheel off.