Home-made chain adjustment tool

[CB750TOM_imp]

While brainstorming for an easy way to measure chain slack, I came up with this. Scroll down to the last image on the page.

http://faq.ninja250.org/wiki/How_do_I_measure_chain_slack?

 

[the Ferret]

Great idea. Think I will make one.. Why is the dowel on an angle and not straight up and down ?

 

[meowguy_imp]

A carpenters combination square placed on the ground works for me. You slide the gauge down to the bottom to form a right angle. Place it on the floor with ruler facing up. Read slack. And you can use it for a lot of other stuff in the workshop. You may already have one in your kit.

Like this:
Combination Square

 

[CB750TOM_imp]

Great idea. Think I will make one.. Why is the dowel on an angle and not straight up and down ?

Only thing I can figure out is that this is a sport bike forum and the bike is at a different angle.

 

[The Spaceman_imp]

A carpenters combination square placed on the ground works for me. You slide the gauge down to the bottom to form a right angle. Place it on the floor with ruler facing up. Read slack. And you can use it for a lot of other stuff in the workshop. You may already have one in your kit.

Like this:
Combination Square

This is a great idea. I have the tool, just need to see if its tall enough to do the job when the bike is up on the centerstand.

While we're on the topic; does anyone else find the CB more sensitive to chain slack than other bikes? I hardly ever adjusted the chain on my Suzuki or Harley, but if I let the CB chain get just a tad too much slack, I really feel it. Especially off-throttle or downshifting.

 

[rboe]

For combination squares sometimes you can get 18" rulers for them.

An alternative is the old Stanley Odd Job (http://www.garrettwade.com/product.asp?pn=23n02.01) that can be found in larger formats.

 

[the Ferret]

Great idea. Think I will make one.. Why is the dowel on an angle and not straight up and down ?

Only thing I can figure out is that this is a sport bike forum and the bike is at a different angle.

Only thing I can figure out is that this is a sport bike forum and the bike is at a different angle.
Maybe on the side stand?

Since ours gets adjusted on the center stand, the distance from ground to swing arm will always be the same. Easy to make a piece that slides right under there. Just make the straw piece an inch an a quarter long. It will have to be moved up the dowel with each slight adjustment though.
Ok took some quick measurements...from center of swing arm pivot to center of rear axle is approx 22 inches, so mid way between would be 11 inches. At that point, while on the center stand I have 14 inches of clearance between ground and swing arm. As long as the dowel sticks up no further than that i'd be good to go.

And yes Spaceman I find my CB extremely sensitive to chain adjustment, but still in 6300 miles I've adjusted it twice I think... But it's due again I can tell.

 

[Deanohh_imp]

Great idea. Think I will make one.. Why is the dowel on an angle and not straight up and down ?

perhaps so that the stick is perpendicular to the run of the chain. Put a couple of small o-rings on the stick and you can roll them up and down for your ref points.

 

[AzBob_imp]

I just use my hand and my eyeballs. It's actually not that critical in my experience (the chain was ridiculously loose when I got it and rode it for 700 miles, didn't really notice much of a difference when I tightened to within spec). Once you get used to what it's supposed to be, eyeballing it is quite easy, IMO. You just don't want it so tight that you snap the chain, nor so loose that it flies all over the place, hitting things. Kind of reminds me of the elaborate apparatus people use to align their rear tire (not that this is elaborate by any means, just that it seems unnecessary to me).

 

[rboe]

I tend to grab the chain and wiggle it up and down to get a feel for it. Once it seems a bit loose I tighten it up.

 

[the Ferret]

Yea you don't have to be super critical, but on the day I'm working on the bike, I think its kinda cool to have a little homemade gauge to play with while Im doing it.

 

[CB750TOM_imp]

A carpenters combination square placed on the ground works for me. You slide the gauge down to the bottom to form a right angle. Place it on the floor with ruler facing up. Read slack. And you can use it for a lot of other stuff in the workshop. You may already have one in your kit.

Like this:
Combination Square

This is a great idea. I have the tool, just need to see if its tall enough to do the job when the bike is up on the centerstand.

While we're on the topic; does anyone else find the CB more sensitive to chain slack than other bikes? I hardly ever adjusted the chain on my Suzuki or Harley, but if I let the CB chain get just a tad too much slack, I really feel it. Especially off-throttle or downshifting.

This is a great idea. I have the tool, just need to see if its tall enough to do the job when the bike is up on the centerstand.

While we're on the topic; does anyone else find the CB more sensitive to chain slack than other bikes? I hardly ever adjusted the chain on my Suzuki or Harley, but if I let the CB chain get just a tad too much slack, I really feel it. Especially off-throttle or downshifting.
250 miles on mine and I have adjusted it twice. ???

 

[meowguy_imp]

Quote:This is a great idea (Combination Square). I have the tool, just need to see if its tall enough to do the job when the bike is up on the centerstand.
The 16" that I linked to will absolutely be tall enough. My standard 12" is not. So I put a small block of wood under it to raise it up. I am too cheap to buy to a new square.

 

[dailyrider_imp]

I just use my hand and my eyeballs. It's actually not that critical in my experience (the chain was ridiculously loose when I got it and rode it for 700 miles, didn't really notice much of a difference when I tightened to within spec). Once you get used to what it's supposed to be, eyeballing it is quite easy, IMO. You just don't want it so tight that you snap the chain, nor so loose that it flies all over the place, hitting things. Kind of reminds me of the elaborate apparatus people use to align their rear tire (not that this is elaborate by any means, just that it seems unnecessary to me).

I never did understand that elaborate craziness of aligning the rear to the front. Your rear needs to be in alignment with the swing arm pivot. I just measure center of pivot to rear axle center on both sides with a tape measure and you're done. If it does not align with the front after this then you have other problems like a tweeked frame or forks.

 

[CIP57_imp]

I tend to grab the chain and wiggle it up and down to get a feel for it. Once it seems a bit loose I tighten it up.

I with you, been doing it long enough to feel the proper tension.

 

[rboe]

If you align the rear wheel with the front then the bike will track properly. That is the rear wheel will follow the front and the bike won't crab down the road like it has a bent frame. Worst case it will handle wonky and go through tires faster.

If you align with the front wheel then the sprockets (drive and driven) should also align and you won't have excessive chain wear (a "fix" that some XR650L owners do is replace the drive sprocket with one from an R model which has more surface area for the splines to register on to reduce the wear on the splines caused by a lack of a cush drive in the rear rim; this causes about a 3mm offset between the sprockets can causes excessive chair wear because the chain goes at an angle between the two sprocket - just like on a ten speed bicycle). Sprockets and chains for our bike are not cheap.

Now I also strongly suspect that most bikes are assembled properly with good parts so that aligning with the swing arm is good enough.

But to align the wheel with the swing arm is false confidence since the swing arm really does not care how it aligns with your drive sprocket or the front wheel and the wheel can be quite cocked in the swing arm and still function properly. Naturally things will only be pretty wonky if the swing arm was defective or your bike suffered a crash and it was bent (or the frame or both).

Now if you did align with the front tire and kept your chain aligned properly with the sprockets you can note where the adjusts end up on the swing arm which can tell you if the swing arm has issues. If things are really off then you should look to see where the problem is. Could be bent forks, frame, swing arm or messed up swing arm markings.

Kinda a twist of the "trust but verify" theme here.

 

[CB750TOM_imp]

For wheel alignment, here's a neat trick. Though, it could be done with 2x4's if they are straight

motorcyclemetal.com

 

[The Spaceman_imp]

I've been reading for years about different methods to align the sprockets, the front and rear wheels, the forks, etc. And how "you can't trust the factory alignment marks on the bike because they're wrong," which is usually followed by some Byzantine alignment process involving fluorescent tubes, the phase of the Moon, and gravimeters. Horsecrap. Unless your bike has been wrecked and the frame is bent, or you've been pounding the forks into a pretzel with poorly done wheelies, in my experience the only "alignment" needed is to line up the rear axle side to side using the marks the factory put on the swingarm.

The local mega dealer got a laser motorcycle alignment system in their shop a couple years ago. VStrom are notorious for headshake at higher speeds (90+) and on decel, so I thought I'd see if they could fix it on my bike with their new toy. After an hour of tweaking and adjusting they declared the bike perfectly aligned. I took it up on I-95, and damn, no headshake! I was amazed. I exited the highway, cut under the overpass and headed back the other way, and by the time I got back to the dealer's exit, the headshake was right back like it always was.

 

[the Ferret]

Just made my chain adjustment measuring tool. Took all of 5 mins since I had everything on hand, a piece of 2x4, a wooden dowel and a straw. I even painted the vertical dowel black to make the straw easier to see. Waiting for paint to dry then I'll put up a pic.

Agree not necessary, but a fun little project for a retired guy with nothing to do. Raining outside so I don't feel like riding. Do have a couple melons to cut up, a cantaloupe and an Indiana melon (grandson likes fruit and it's my day to watch him tomorrow). Watching deer feed out the back window, and playing on the internet lol.

 

[rboe]

Oil threads, torque wrenches and chain alignment. Things to avoid on a forum. :celebrate: