[Vicc]

Hello everyone, I just got a brand new 2013 CBR250 and I'm a complete noob to riding. I have the bike sitting in my living room and has not been ridden at all yet, still at 0kms.

I have one concern, I looked at the rear wheel alignment marks on both sides and they are not the same. So what I'm wondering is if I should try to align them or if I should leave them as they came. Please feel free to suggest what the best course of action would be.

The first pic is of the left side of the bike, as if you were sitting on it. I highlighted the mark with a black line, and the red arrow pointing to it.

In the second pic you can see there is no space between the mark and the black casing as in the first pic.

 

[Giko]

Check your manual for instructions. It's quite simple to do.

 

[MotoMike]

... I have one concern, I looked at the rear wheel alignment marks on both sides and they are not the same. So what I'm wondering is if I should try to align them or if I should leave them as they came. Please feel free to suggest what the best course of action would be...

Using a tape measure, take a measurement between the center of the swing arm pivot bolt, and the center of the axle bolt on each side and compare the measurements. Obviously you want the measurement to be the same on each side. It's possible to have the rear wheel in alignment, even though the adjuster hash marks are not quite the same from side to side. The key is to measure as accurately as possible. If you need to make an adjustment, follow the instructions in the Owner's Manual.

 

[shisoshin]

well done spotting it anyway, this is the beginning of
a fruitful and beneficial habit of mind..
curiosity and interest in 'how things work' etc
can help you develop motorcycling skills..

this is a good example of where you cant be
too precise, where going for accuracy is not
a waste of time or energy..
bear in mind then that alignment marks
are there for general alignments and for
easy convenience, which has a value..
but there are other methods available
[good eg above by motomike]
if you want to get into it..

you can also do fairly easy checks
of wheel rim to inner swing arm..
when you loosen retaining nuts
play around with moving parts
both sides, going for equality of
both sides, not just the marks,
then set it, then tighten..

note any differnce between careful
measurements [as per motomike etc]
and your stamped alignment marks..

bear in mind also that even small movements
of wheel via axle via adjustment nuts can
cause movement in the chain, as you look
along it from the rear,, like sighting a rifle..
if youre within reasonable adjustment range
and notice your use of adjustment nut
causing the chain to bow outward a bit,
try to find alignment which keeps
the chain straight and not bowed..

with the bike inside your house
this is something you need not
get perfect first time but can start
over again and investigate as often
as you like

 

[efoo]

I agree with shisoshin; nice job recognizing it! I would also suggest getting a service manual if you are interested in becoming familiar with your bike. I've already saved hundreds by doing things myself, with the help of my manual, rather than going to a dealership. And I have learned A LOT about the bike in the process

 

[roadster]

The discrepancy shown in your photos is quite small but the advice to look along the top chain run and make sure its absolutely straight is good. You may need to move the chain guard to do this.

The purist would say that what matters is that the front and rear wheels are in line when the bike is upright (see my simple diagram showing plan view of wheels). This really needs a paddock stand to hold the bike upright. Several methods can be used including a long straight edge or a length of string. But it can also be done by eye if you lay on the ground in front of the bike.

Regards Roadster

 

[Vicc]

Thank you all for your replies
I have followed MotoMike's advice and measured it with a tape measure and found the difference to be very tiny, about 1mm.
I'm also going to look at the chain when I have more time to make sure it is straight as Shisoshin mentioned.
roadster, thanks for your explanation and your pic, I saw this process mentioned in some videos on youtube but I wasn't sure how or what exactly to do. But your diagram explains it perfectly.

 

[jsonder]

If you roll the bike forward and back, and then look at whether the chain is centered on the rear sprocket, you will have another way to note if it is not aligned. I try to look at that before starting the bike, but, it sometimes is forgotten.

 

[pooder7]

For chain alignment, I have this simple and quite effective tool:
Motion Pro Chain Alignment Tool - Street Motorcycle - Motorcycle Superstore

 

[CBR_Dave]

Using a tape measure, take a measurement between the center of the swing arm pivot bolt, and the center of the axle bolt on each side and compare the measurements. Obviously you want the measurement to be the same on each side. It's possible to have the rear wheel in alignment, even though the adjuster hash marks are not quite the same from side to side. The key is to measure as accurately as possible. If you need to make an adjustment, follow the instructions in the Owner's Manual.

Thanks Mike - genius!

I tried that on mine, but the rear sets are a little in the way - the tape measure touches them slightly. In any case, I measured and and my left side measurment is 22 3/4" while the right is about 1/16" shorter than this.

Is 1/16th" (say 1.6mm) difference okay? However, I still can't help thinking that any slight difference in rear set positioning/tolerance between the sides is partly at fault...

EDIT: I have re-measured a little more, and carefully avoiding touching the rear set on the right (the left is okayish). I reckon its maybe 1/32nd of an inch.

Dave

 

[MotoMike]

Thanks Mike - genius!

I tried that on mine, but the rear sets are a little in the way - the tape measure touches them slightly. In any case, I measured and and my left side measurment is 22 3/4" while the left is about 1/16" shorter than this.

Is 1/16th" (say 1.6mm) difference okay? However, I still can't help thinking that any slight difference in rear set positioning/tolerance between the sides is partly at fault...

Dave

1/16th" is pretty close. From there you can really dial it in... you should look at the drive chain side to side runout on the rear sprocket. You'll need the bike up on a rear paddock stand, then while spinning the tire/wheel by hand, look to see if the chain is running centered on the rear sprocket, as viewed from the rear. If the inside of the chain side plates are equidistant to the sides of the rear sprocket, your alignment is golden. If the chain is running tight against one side of the rear sprocket, make small adjustments to the chain adjuster nuts until the chain runs centered on the sprocket. The key here is to make small adjustments for alignment, so as not to throw off your chain free play (deflection) setting. Setting free play should be done first, then final alignment... after you've done this a few times, you'll find that you can actually do both free play & alignment at the same time.

 

[CBR_Dave]

1/16th" is pretty close. From there you can really dial it in... you should look at the drive chain side to side runout on the rear sprocket. You'll need the bike up on a rear paddock stand, then while spinning the tire/wheel by hand, look to see if the chain is running centered on the rear sprocket, as viewed from the rear. If the inside of the chain side plates are equidistant to the sides of the rear sprocket, your alignment is golden. If the chain is running tight against one side of the rear sprocket, make small adjustments to the chain adjuster nuts until the chain runs centered on the sprocket. The key here is to make small adjustments for alignment, so as not to throw off your chain free play (deflection) setting. Setting free play should be done first, then final alignment... after you've done this a few times, you'll find that you can actually do both free play & alignment at the same time.

Cheers Mike,

Ive re-measured and its probably more like 1/32nd. I have had it up on a paddock stand when lubing the chain, and looked at the rear sprocket while rotating the wheel. Although this was just me pawing over my bike, and not looking for the "side to side runout", I didn't notice the chain not being centered (and I think I would have). So hopefully its fine

I'm going to have the bike looked at a service centre in the next few weeks (fix my speedo issue: http://www.cbr250.net/forum/cbr250-problems-issues/8724-speedo-reading-jumps-around.html#post119104), and have the rear brake checked out (there must be something stuck in the pad - I can hear a slight scrape when rotating the wheel slowly, and there is some light scoring on the rotor). So I'll have them check the chain alignment to be sure as well.

Thanks again,

Dave

 

[efoo]

and have the rear brake checked out (there must be something stuck in the pad - I can hear a slight scrape when rotating the wheel slowly, and there is some light scoring on the rotor). So I'll have them check the chain alignment to be sure as well.

"I'm no expert", but I think that a light scraping sound is normal. You don't want it so much that the wheel cant spin, but at least enough for a couple revolutions. I would guess that you don't want a gap between the rotor and the pads because it would be easier for particles to get in there, and you may not get the same braking power when the pads are further away.

I also have some light scuffing on the rotor face from installing the rear wheel myself but it is superficial and doesn't seem to affect the braking power.

 

[CBR_Dave]

"I'm no expert", but I think that a light scraping sound is normal. You don't want it so much that the wheel cant spin, but at least enough for a couple revolutions. I would guess that you don't want a gap between the rotor and the pads because it would be easier for particles to get in there, and you may not get the same braking power when the pads are further away.

I also have some light scuffing on the rotor face from installing the rear wheel myself but it is superficial and doesn't seem to affect the braking power.

Its not the normal pad dragging on the rotor. Its a distinct scraping (not dragging/rubbing), and there is a light score mark on the rotor . It's not "normal".

Dave

 

[MotoMike]

Yeah, it's completely normal to hear that light scraping sound when rotating a wheel by hand with disc brakes. The brake pads ride so close to the rotor, that even the slightest amount of side to side runout in the rotor will cause it... no worries.