I get asked all the time “How often should I check my drive chain?”.
The answer is: probably way more often than any of us currently are. I’m guilty of it too. The thing is, with proper care and feeding, your drive chain can last well over 10,000 miles. If neglected, you can look forward to sloppy performance, and having to replace both your chain and sprockets (easily a $200 expenditure) way more often. So, if the chain slap and lackluster performance doesn’t motivate you, how about you tackle the task for your wallet?
Maintaining your own drive chain is the sort of task that gets quicker and easier every time you do it. If you stay on top of it, only minor adjustments need to be made. Properly maintained chains just chains run quieter. Dialing in the recommended drive chain slack improves performance (making the bike feel much more responsive to throttle). A clean, lubed and adjusted chain is a happy chain!
So, let’s get on with it.
Clean & Lube
All that road grime and grit that accumulates on your chain ends up acting very much like valve grinding compound on the teeth of your sprockets and links of your chain. An unfortunate side effect of chain lube is that while it’s sticky nature adheres to the chain well, it also captures dirt, grit and grime. Regularly, we need to clean that sucker up and keep the grinding at bay.
There’s no doubt that keeping your chain clean will extend its service life, but there is some controversy as to what product to use when cleaning your chain. The issue here is specifically concerning O-ring chains. Those little “O” or “X” rings are designed to keep grease where it’s needed (the pins of your chain) and dirt out. The trick is to find a solvent that is good at removing grime, but doesn’t penetrate past the O-rings and remove that grease.
There are several products out there that are for cleaning chains that are specifically “O-ring safe”. (My lawyer want’s me to stress that you should always use an “O-ring safe” product!) Myself, I’ve had great luck with WD-40. One, it’s a great de-greaser (the main ingredient is Kerosene), and 2nd; it’s availability. There always seems to be a can of it within reach. In my experience, chains seem to last much longer if I keep them clean, regardless of the product I choose to clean them with. I guess this is a case of do as I say, not as I do. J
First, we need to get your rear wheel off the ground. Those of us with super lame center stands installed, this is the moment you’ve been waiting for! For the rest of us, we got some finagling to do.
With the rear wheel propped up just high enough to be able to freely spin the wheel, you may begin.
My technique? While your left hand holds your cleaner of choice, the right hand is free to spin the wheel. I recommend rotating the wheel counter clockwise and focusing all cleaning on the lower span of the chain.
Pick an area on the chain where overspray will not hit your rear tire. Yes, this is going to be a bit messy. Best put a drip pan under the bike, or a scrap piece of cardboard. I highly recommend latex gloves for this operation.
Give the chain a good soaking with the de-greaser, and start wiping off the grime with paper towels or mechanics rags. Be careful with your hands! It’s surprising easy to lose focus for a second and get your fingers (or rag) caught up in the rear sprocket of a moving chain (Ouch!). Rotating the rear wheel clockwise minimizes this risk as it keeps the chain moving away from the rear sprocket.
Take note of any loose or tight sections of your drive chain. Sometimes your chain will wear unevenly, and you’ll want to adjust your chain slack on the tightest section of chain later. A “loose/tight” chain accelerates wear to your sprockets, so if you find that this is the case, best plan on replacing your chain and sprockets in the near future.
Once your chain is significantly cleaner (don’t expect to get it back to “like new” condition), using the same technique, apply a liberal amount of chain lube to the drive chain. Again, pick a good location on the chain where over-spray from the lube will not hit an unintended target. The object here is to lube your chain, not your rear tire.
The object here is to give it a light coating of lube, not a soaking. If you over-lube your chain, most of the lube will fling off and create an oily mess on your chain guard, rear fender and left pant leg. Not sexy.
Wipe off any excess lube and call it cleaned & Lubed.
The goal here is to properly measure your chain’s slack, and adjust if necessary.
Your bike will need to be back on the ground to properly measure chain slack. (on the kickstand is fine) Whatever sketchy method you used to prop up the rear wheel for cleaning needs to be removed. The full weight of the bike needs to be on the rear wheel to measure and adjust chain slack accurately.
Refer to your owner’s manual for your bikes recommended chain slack specifications. Manufacturers often list a range of acceptable chain slack, like “25 to 35mm”. Having your chain adjusted to anywhere within that specification is the goal. There is no real performance benefit to adjusting your chain to either side of that specification, so don’t over think it! This isn’t rocket science. You’ll be doing this adjustment on the side of the road without a ruler when you get really accustomed to it. J
You’ll want to pick a measuring spot on the chain approximately in-between the front and rear sprocket, where the greatest amount of movement is possible. If you noticed a tight section of chain while cleaning, rotate the rear wheel so the tightest section runs along the bottom.
Pick a spot on a single link of the chain from which to base your measurements off of.
With your left hand, hold the ruler. With your right hand, put a single finger’s pressure on the chain and find it’s lowest point. (we don’t need a lot of pressure for this measurement, just light pressure)
This is your starting point. Now with the same single finger’s pressure, lift the chain and find it’s upper limit.
Again, measuring from that specific point on the link, find the difference between the lower and upper measurements. In this case the difference between 40mm and 20mm = 20mm.
This is your total chain slack.
If you are within specifications, it’s Miller time! Otherwise, we have some adjusting to do.
Chain Tension Adjustment
The procedure that follows applies specifically for traditional style (dual sided) swingarms. If you have a super swanky single-sided swingarm, Nice. That’s some next level ish! The techniques below will apply in theory, but the means of adjustment will be very different. Definitely read on, but consult your owner’s manual for the finer points of single sided swingarm adjustments.
To adjust your chain’s slack, we will be using the axle adjusters on your swing arm. Axle adjusters come in several varieties, but most often that the form of a locknut and adjusting bolt on the very end of the swingarm.
To increase tension on the chain, we will be moving the axle back(This is most typically what you will be doing, as chains stretch as they wear). If your goal is to introduce slack into the chain, we will want to move the axle forward. Take a minute to visualize in your mind what it is you want to accomplish (do I need more tension, or less??). It’s easy to go in circles if you don’t fully visualize the end goal.
Now, look at your bike’s adjusters and decide how they operate. Some axle adjusters push and pull the axle into position, and others just make room for you to manually move your axle to a different position.
While making these adjustments, we also want to make sure and adjust each side of the axle the same amount, keeping the axle perpendicular in the frame. There are little markings on your adjusters to help you judge this.
Again, relax. If this adjustment had to be down the molecule, they would have made the marks a lot closer together. 🙂 Close is close enough.
OK, enough technical and theoretical prep. No worries, you will learn quickly by doing. Let’s just dive right in.
Start by loosening your rear axle nut.
The axle needs to be loose enough to be able to make your adjustments, not so loosey goosey that it won’t stay where it’s just been adjusted to.
Loosen the lock nut on your adjusters.
Slacken the lock nuts off so they are well out of the way, giving you room to freely adjust.
All that mental preparation and High school physics 101 flashbacks have brought you to this very moment. You’ve taken measurements, checked specifications, visualized exactly what you want to accomplish. Let’s adjust.
Make small (equal) adjustments to each side of the swingarm’s axle adjuster! You will be surprised how little adjustments translate into a big difference in chain tension.
You might only need a small tweak to be within spec.
Making equal adjustments on both sides, and check your chain tension after every adjustment.
Once you have your chain’s tension within acceptable range, double check your axle’s alignment. The adjusters on both side of the swingarm should be in the same position.
If your axle’s alignment is off, even up the axle with the adjusters and adjust for tension again. (here’s where the adjusting in circles can come in). I find if you first start with the axle perpendicular in the frame, and make small / equal adjustments to each side… you won’t be very far off.
Once the chain slack is within spec, and you’ve confirmed that your axle is indeed perpendicular in the frame…. we can start buttoning up.
I suggest snugging down the axle nut first (we’ll do a final torque later), and then confirming again that nothing has moved. If you are happy with both the chain slack and the axle adjustment, do the final torque on the axle, and then snug down the lock nuts on your both of your axle’s adjusters.
With one wrench, hold the adjuster in position, with the other wrench, tighten up the locknut. Resist overtighteing the adjusters lock nuts! They strip easy. Besides, if you over tighten them.. think about the next poor schmuck who’ll have to loosen them up next adjustment…. you!
Do your final check on both the axle alignment and chain slack to make sure you are happy with your work.
Don’t forget the cotter pin on the axle’s castle nut if you have one! If you bike’s axle nut is a lock nut, torquing it is all you need.
Congratulations, you have reached yet another milestone in your quest to be one with the wrench! (And I’m pretty darn proud of you!)
If you’d like to get some real world experience on this procedure, Moto Republic offers a “Chain & Sprockets Workshop" monthly, and private one-on-one instruction is available as well.
Check out our current Workshop and Class listings here: Workshops & Classes