Yamaha FZ-09 Forum banner

1 - 20 of 37 Posts

·
Registered
Joined
·
34 Posts
Discussion Starter #1
About 3 weeks ago I hit a rock a bit larger than the size of a fist at about 40mph on the left side of my front wheel. It put an almost unnoticeable bend on the lip of the wheel on the left side.

I dont know if the bike always handled like this or not, but when I let go of the handlebars the bikes starts going left, enough that i have to lean my body to the right to keep it straight.

Did something get misaligned or do all these bikes handle that way?

Sent from my SM-G975U1 using Tapatalk
 

·
Registered
Joined
·
4,482 Posts
Could be the dent or front alignment. Mine always pulled sightly to the right away from the camber of the road (higher in the center). Left lane riders in the U.K. said their bikes pulled to the left, again, away from the center line.

Checking front to wear wheel alignment sounds like a good plan.
 

·
Registered
2016 XSR900 60th Anniv. Edition
Joined
·
1,646 Posts
...an almost unnoticeable bend on the lip of the wheel on the left side.
That's not going to make a difference at all.

If you think the whole rim might be out of whack, you can check it. Lift the front end a bit, either with a stand, or even a block of wood under the right fork leg while it's on the sidestand. Once you can spin the front wheel freely, wrap a zip tie around the fender support and adjust it to where the little"tail" is pointed right at the wheel rim, with a sliver of daylight between them. Rotate the wheel and you'll see if there's any change in the runout.

Most likely causes of the bike pulling:

- Crown of the road. Check different sections of road and see if it's any different.

- Wheels are not aligned. Fix this with the chain adjuster. (Several methods can be found all over the internet)

- Your own riding style. Make sure you're centered. Equipment is symmetrical. (Even running a single bar-end mirror can steer your bike off center above certain speeds)

- Serious damage to the frame or suspension. Much more than a minor wheel ding before you'd notice anything.
 

·
Registered
Joined
·
34 Posts
Discussion Starter #4
I thought I had the rear wheel properly aligned but might need to redo that. I live in the US so the bike should naturally go to the right correct?

Is it possible the impact caused a misalignment with the handlebars and wheel? How would I correct that?


Sent from my iPad using Tapatalk
 

·
Registered
2016 XSR900 60th Anniv. Edition
Joined
·
1,646 Posts
When the road is crowned (in the US), it's generally higher on the left. So the contact patch of the tire is left-of-center, which makes the tire veer left. However, because of the countersteering effect, the bike itself wants to lean right. To correct, you'd be pushing slightly on the left handlebar.

Sometimes, on divided highways, the road can drop on both sides, so the left lane will affect you in the opposite manner of the right lane.. In any case, the bike will always try to go "downhill" on its own, so you have to steer into the high ground...
 

·
Registered
Joined
·
34 Posts
Discussion Starter #6
When the road is crowned (in the US), it's generally higher on the left. So the contact patch of the tire is left-of-center, which makes the tire veer left. However, because of the countersteering effect, the bike itself wants to lean right. To correct, you'd be pushing slightly on the left handlebar.

Sometimes, on divided highways, the road can drop on both sides, so the left lane will affect you in the opposite manner of the right lane.. In any case, the bike will always try to go "downhill" on its own, so you have to steer into the high ground...
I see, it might also be my posture. I tend to carry a large bag for school on one side and my body leans to the left when relaxed but im not sure if thats the main cause.

Whats your preferred method to align the rear wheel if you dont mind me asking?

Sent from my SM-G975U1 using Tapatalk
 

·
Registered
2016 XSR900 60th Anniv. Edition
Joined
·
1,646 Posts
I have a lift, and a fancy caliper-like tool that measures between the swingarm pivot and the axle on both sides. I'm not normal. ?

If you have a rear stand, you can get a pair of straight-edges (Aluminum angle works well, as it's usually very straight), and using some wood blocks to raise the straight edges up above the sidewalls, you can measure the gap between the front tire and the straight edges. I can give you more detail if you want to try this method.

Other people use string to do it, but that seems pretty fidgety to me.

An easy way to get a quick visual check of your alignment is to have a buddy follow you, maybe 100 feet back, on as flat a road as you can find, and just spot your front tire. As they move left and right in the lane behind you, if they can see the front tire more easily on one side than the other, it's out of alignment. I've seen this on friends' bikes when foolowing them, and it's pretty obvious if it's not tracking straight.
 

·
Registered
Joined
·
34 Posts
Discussion Starter #8
I have a lift, and a fancy caliper-like tool that measures between the swingarm pivot and the axle on both sides. I'm not normal.

If you have a rear stand, you can get a pair of straight-edges (Aluminum angle works well, as it's usually very straight), and using some wood blocks to raise the straight edges up above the sidewalls, you can measure the gap between the front tire and the straight edges. I can give you more detail if you want to try this method.

Other people use string to do it, but that seems pretty fidgety to me.

An easy way to get a quick visual check of your alignment is to have a buddy follow you, maybe 100 feet back, on as flat a road as you can find, and just spot your front tire. As they move left and right in the lane behind you, if they can see the front tire more easily on one side than the other, it's out of alignment. I've seen this on friends' bikes when foolowing them, and it's pretty obvious if it's not tracking straight.
I see ill have to do my research sounds complicated .

My method for alignment was using a small digiter caliper and measuring the distance from the center of the swingarm spool bolt to the edge of the little alignment plate on the axle. Not sure if this method is accurate but for the most part the marking on the swingarm appeared to align on both sides.

What do you think would be a good method to see if the handlebars align with the front wheel?

Sent from my SM-G975U1 using Tapatalk
 

·
Registered
2016 XSR900 60th Anniv. Edition
Joined
·
1,646 Posts
157414

Here's a rough diagram (using my finger on my iPad, so cut me some artistic slack! ?). The blue lines are the straight edges, sitting on blocks. The bike needs to be as vertical as possible, which is why a rear stand is best. Align the straight edges along the sides of the rear tire so they're perfectly parallel. Then measure the gaps between the front tire and the straight edges, seen here in green. All four gaps should be the same, within a couple mm of each other, at least. If not, use the chain adjusters on the swingarm to realign the rear wheel until they match...
 

·
Registered
Joined
·
34 Posts
Discussion Starter #12
View attachment 157414
Here's a rough diagram (using my finger on my iPad, so cut me some artistic slack! ). The blue lines are the straight edges, sitting on blocks. The bike needs to be as vertical as possible, which is why a rear stand is best. Align the straight edges along the sides of the rear tire so they're perfectly parallel. Then measure the gaps between the front tire and the straight edges, seen here in green. All four gaps should be the same, within a couple mm of each other, at least. If not, use the chain adjusters on the swingarm to realign the rear wheel until they match...
Interesting ill try that out . Just gotta get some straight edges from home depot

Sent from my SM-G975U1 using Tapatalk
 

·
Premium Member
Joined
·
2,429 Posts
I guess the only issue is getting the front wheel perfectly straight for you dont get incorrect results

Sent from my SM-G975U1 using Tapatalk
Not really because if you measure at the center of the front wheel, well it's the center.
Obviously you need to eyeball it as close as you can and if it's a few millimeters off, well this isn't Moto GP.
 

·
Registered
Joined
·
34 Posts
Discussion Starter #16
Not really because if you measure at the center of the front wheel, well it's the center.
Obviously you need to eyeball it as close as you can and a few millimeters off, well this isn't Moto GP.
Any idea how I would detect if by chance the rock impact twisted the forks a bit or misaligned them from the handlebars?

Sent from my SM-G975U1 using Tapatalk
 

·
Registered
2016 XSR900 60th Anniv. Edition
Joined
·
1,646 Posts
I guess the only issue is getting the front wheel perfectly straight for you dont get incorrect results
Just measure one side at a time. Twist the front wheel, if necessary, until the forward and rear measurements are the same, then check the other side.


Any idea how I would detect if by chance the rock impact twisted the forks a bit or misaligned them from the handlebars?
Again, it's very unlikely. Especially if you can't see any obvious damage to the front wheel...
 

·
Premium Member
Joined
·
2,429 Posts
Teddy, if the forks got tweaked in the headstock you would notice the handlebars being crooked when you're riding.
 

·
Registered
Joined
·
34 Posts
Discussion Starter #19
Just measure one side at a time. Twist the front wheel, if necessary, until the forward and rear measurements are the same, then check the other side.




Again, it's very unlikely. Especially if you can't see any obvious damage to the front wheel...
Thanks, my bad just paranoid since its a new bike haha

Sent from my SM-G975U1 using Tapatalk
 
1 - 20 of 37 Posts
Top