I have a 2002 Yamaha FZ1 with about 43,000 miles. Great bike. Recently I noticed head shake if I took my hand off the bars when going straight down a smooth road. I didn’t used to have this at all. The front tires where pretty shot with some minor uneven wear so I figured this might be the cause. I put a brand new tire on and still have the issue. Any suggestions on what to troubleshoot?
Check your steering head bearings for wear or looseness. Have you had your forks serviced? In an odd case, uneven fork wear can make it where one side is not providing enough suspension that can cause the uneven wear on the tire which can contribute. How is the rear shock, is it worn? If the rear is sagging more, it may have changed the geometry of the bike. Did you balance the wheel when you put new tires on? Have you made any other suspension changes at all recently since this has occurred?
-head bearings/ stem tension -has the bike been crashed? -does the wheel spin freely on a front stand -caliper drag? -tweaked rotor -bad wheel bearings?
No suspension changes but neither the forks nor shock have been service in a long time and are stock. No crashes. I changed and balanced the tires myself which I’ve done multiple times with no issues. The wheel spun easily and smoothly so I don’t thin wheel bearings are the problem. Rotors appeared straight when I checked them visually while balancing. No unusual caliper drag. I’m thinking I need to check the head bearings. I had a bad crash about 10 years ago at Nelson Ledges racing an R6 that went onto a tank slapper coming out of turn 3. Turned out the head bearings were loose.
Install All Balls tapered head bearings. Service the forks. Put the fork tubes in a lathe, check runout, and polish them while they’re in there. Install new upper and lower bushings, as well as new oil and dust seals. Service the shock. Pull the swingarm and check/service/replace the pivot bearings. Likewise, do the same with the shock linkage. Double-check tire balance on both ends. They should be of matching brand/model. Certain tire construction types are not compatible with each other. Beyond all this, double-check the FZ1 forums to see if the tires you’re using are a known problem for that bike.
When I bought my '02 few years back, the PO had similar complaint as he just installed new tires. I'm not a "hands off the bars" rider, but tried it to verify and yup, shook like he said. I started by re-torquing the steering head bearing nut. Reassembled the top clamps and tightened top stuff. Then loosened front axle, fork pinch bolts and calipers, then did the fork bouncy thing, retightened in sequence. No shakes and wobbles since, so not sure if was steering bearing nut retorque of something was bound up from his tire swap.
If you rode it too long with the steering bearing not adjusted, re-greased, etc, they can sometimes wear a 'notch' in the bearing race, in which they will need to be replaced. I have cured many wobbly bikes with careful steering head bearing maintenance.
A LOT of the negative reputation of All Balls comes from the offroad crowd who ride it hard and put it away wet, perform zero maintenance, and judiciously use a pressure washer/car wash. Those guys are the worst and can potentially kill a business with their stories of blame, which is never their fault. I’ve used All Balls tapered head bearings in my last four bikes, 3 of which I still have, and have had zero problems.
We started using them when they first came out. They were fine back then. Most rodrace bike would last at least 2-3 year without needing new ones. Now you are lucky to get a year out of them.
Fortunately, i'm not one of those guys. I'm still running, original belt, wheel bearings, axles, u-joints, carrier bearing....I was running original ball joints and tie rods until i put 2" forward A-Arms on it this year and it was just easier to install new BJs and I had to use an upgraded tie rod kit with the A-Arms...'18 RZR XP Turbo.
The All Ballz tapered bearings I do NOT recommend for an R6. There is no channel for a punch like on a Suzuki, so if they ever need to come back out you're cutting the race.
A friend just bought a <1 yr old dirtbike with less than 10hrs that had the stem bearing rusted stiff. He noticed the front felt "stiff" on the test ride but figured the tire had lost air. After getting it home & doing the standard prep he took the triples apart to find the seized bearing. He called the prev owner and they had used a pressure washer & put the bike up.
Run a small bead around the inside surface with a TIG welder and they come right out..everyone has a TIG in the garage right??
