chain tensioner blocks

just noticed last night the brake side has 11 alignment marks and the sprocket side only has 9, which way are you meant to count the marks.

my dirt wheel have the marks at the end of the block (furthest away from the engine) and ,my road wheels sit on the 1st mark on the blocks ( closer to the engine) when i swapped my wheel i noticed the brake side looks to be sitting further back, the bike seems to ride fine.  

I forget now, but the blocks may be marked on both sides. I wonder if the side against the swingarm has a matching set of marks.

Regardless, I'd measure from the leading edge of the blocks and see if you can find some common measurements.

You can use a chain alignment tool then punch your own marks.

Don't worry about the marks so much as wether or not the chain/tire looks straight.
their just guidlines.
I switched to the no longer made SME sliders with rear blocks a long time ago.
Noticed right away they had more acurate marks.

I measure with a tape from the axial to the centerpoint of the pegs. I think this works well as long as the pegs aren't bent. I need to find a better point on the frame to do this.

mordicai wrote:

I measure with a tape from the axial to the centerpoint of the pegs. I think this works well as long as the pegs aren't bent. I need to find a better point on the frame to do this.

I have a similar approach, but I run dowels through the swing arm pivot and the axle.  Then measure (c-c) on both sides of the bike.

DragonNester wrote:

mordicai wrote:

I measure with a tape from the axial to the centerpoint of the pegs. I think this works well as long as the pegs aren't bent. I need to find a better point on the frame to do this.

I have a similar approach, but I run dowels through the swing arm pivot and the axle.  Then measure (c-c) on both sides of the bike.

Thats a good solution. I will buy some dowels and try it.

Has anyone used one of those "Laser" chain alignment tools? The one I saw online had a magnetic back that would attach onto the rear sprocket. rotate the wheel to get tension on the chain and see how it aligns with the laser.

I have the Motion Pro clamp on thing with the rod. Cheap, simple, works great.

One word of caution about using the MP alignment tool. Since we are supposed to set the slack with the bike on the side stand, I don't know, but it seems to me you need to have your bike on a lift and vertical for this tool to be accurate. My thinking is, if there is slack in the chain it could swing off center to the left and give a false alignment reading. The official video by Motion Pro does show the demo bike on a lift, back wheel off the deck and vertical.

I simply measure the distance from the tire to the swingarm on each side by the front of the tire to check alignment.

The zeta axle blocks I have also seam to have accurate marks so I just go by them now.

Sorry guys, You can measure, count marks,do anything you wish but the only true way is to end up with the rear sprocket running down the center of the chain while rotating the wheel in the forward direction. Berwyn

Berwyn Henderson wrote:

Sorry guys, You can measure, count marks,do anything you wish but the only true way is to end up with the rear sprocket running down the center of the chain while rotating the wheel in the forward direction. Berwyn

+100  


Spin rear wheel....watch how chain tracks over sprocket, and between sprockets. Done.

For those of you that use the "observe the sprocket teeth to the chain center while spinning the rear wheel - align as necessary method", have you checked it against the measurement methods to see if there is any noticeable difference in the results.  Just wondering how little misalignment would be noticed with this method.  In other words, can the alignment be off and not noticeable using that method.  Can't imagine it as accurate as long length side per side measuring.

Talk to me.

It is the only sure way to do it. If the wrong spacers are used this will tell. If one runs the chain to one side or the other you will get chain and sprocket ware. Remember that one needs to rotate the wheel in the forward direction. Never checked the marks afterward but do use them to get in the ball park to begin with like when installing a new chain or gearing change. Berwyn

OK, let's say you have the right spacers on the axle and the chain is within the recommended slack range.  What you are trying to do now is ensure the axle and swing arm bolt are parallel...being the two sprockets are in the same plane (directly behind each other).   Or, in other words, the axle is (as precisely as possible) 90 degrees to the center line (front to back) of the swing arm. Any little difference in alignment will show up when measuring each side (c-c) between the two.  We're talking fractions of a degree.   All I'm wondering is if you use the eyeball method can you be sure you are as precise?  Measurements can't lie.  Just double check to see if you got it right next time to see if you're really running true.

Guys, I didn't know we were building a WATCH !! Berwyn

There's a great micro-brewery 10 miles away. We both want to go there because they're having a huge party and giving away free beer and shirts and stuff.

You decide to jump on the intestate and blast straight there at about 70 mph.

I decide to take the back roads where the top speed is only about 45 mph, but the curves and twists and hills and dips make for a smashing good time.

Bottom line - we both get there.

Are either of us "wrong" on how we got there?

I think not.  

   

thanks for all of your methods, wheel is now aligned, as for the alignment marks, count them from the rear of the bike.

motokid wrote:

There's a great micro-brewery 10 miles away. We both want to go there because they're having a huge party and giving away free beer and shirts and stuff.

You decide to jump on the intestate and blast straight there at about 70 mph.

I decide to take the back roads where the top speed is only about 45 mph, but the curves and twists and hills and dips make for a smashing good time.

Bottom line - we both get there.

Are either of us "wrong" on how we got there?

I think not.  

   

All I asked, using your method, does it get you to the front door of the micro-brewery or just to the neighborhood?  A quick check would tell.

Don't know if you'll ever get it truly perfect. The best way to make sure its equal is to measure from the swing arm to the axle.

What I do is,  I start on the left side and get the chain where I want it, tighten the bolt and then take a Digital caliper http://www.harborfreight.com/6-inch-digital-caliper-47257.html and measure (A) the left side screw and adjust the right side so that they are the same exact length from the bolt.

DON'T MIND THE BENT AXLE BLOCK. OLD PICTURE, BUT IT WAS THE BEST TO ILLUSTRATE THE MEASURING POINTS.


Then i measure the axle blocks from the edge to the end of the swing arm (B) Tighten the axle a bit and remeasure to ensure things have stayed equal.

I'm happy with a  +/- .02 on each side. (My engineering side comes out =p ) That .02 won't be noticeable unless you hit some ridiculous speeds and forces

The best way is to make sure the chain is straight regardless of how far the adjusting bolts are out. The little Motion Pro gizmo works very well. Pretty easy to get it perfect with that.

bluzharp wrote:

The best way is to make sure the chain is straight regardless of how far the adjusting bolts are out. The little Motion Pro gizmo works very well. Pretty easy to get it perfect with that.

How do you know that the Motion Pro gauge is perfectly straight?