With the popularity of old school aesthetics, a growing number of Harley-Davidson owners keep asking about Sportster chain conversions. Will converting a Sportster to chain drive help increase performance? Are there any other benefits? What are the pros and cons of converting a Sportster to chain drive? Can I fit a bigger rear tire with a Sportster conversion kit?
We’ll cover everything you need to decide what’s best for you.
A Sportster chain drive conversion can potentially give you some performance benefit, though you probably won’t ever notice it. Switching to chain drive could also help you fit a larger rear tire too. Other than that it’s primarily an aesthetic modification. Converting your Sportster to chain drive comes with some downsides, including a lot of extra maintenance.
Watch the video or check out the rest of the article to get the full picture of what exactly to expect from a Sportster chain conversion.
7 Advantages of a Sportster chain drive conversion
There are several advantages to converting your Sportster to a chain drive. Let’s review what we stand to gain from this potential final drive conversion.
More space for fatter tires
For decades, Sportsters came from factory with a narrower tire than many other Harley-Davidson models, and a lot of riders like the fat tire look. One of the problems with belt drive is that you only have so much clearance to work with. That means you only have so much room to increase the tire size.
Riders who want to put a fat tire on their Sportster might want to consider a Sportster chain drive conversion as it could give them more room to fit a fatter tire. How fat will depend on what year their motorcycle is from.
Do chain drive Sportsters look better?
Some motorcyclists believe that, even without a fatter tire, chain drive Sportsters just look better. The Sportster is an old school motorcycle, that first came out in 1957. Putting a chain drive on a Sportster keeps the motorcycle a little more true to its origins.
Of course, there have plenty of upgrades since 1957, and plenty of different models of Sportsters over the years as well. Not every upgrade over the years has options available for going back in time. You’ll have to decide on whether chain drive looks better for yourself.
Are motorcycle chains stronger than belts?
Chains are stronger than belts, but for most riders the difference in strength doesn’t matter because a belt is strong enough for their use. For example, you’re running a 120+ horsepower special-purpose Harley-Davidson that has been heavily customized for drag racing, chain strength is an advantage you should take seriously.
For the rest of us, even those with an S&S Cycle 1,250cc big bore kit, a belt is plenty strong. Sure you’ll have people who will chime in that a belt left them stranded. This has definitely happened to people and the experience will leave you bitter, or worse, but when you think about the millions of belt-driven motorcycles out there, some are unfortunately bound to fail. Likewise, because there are millions of chain-driven motorcycles on the roads, many chains also fail.
Still, we should point out, that one-in-a-million stone bouncing into the wrong place at the wrong angle could do same damage to a belt, but a chain’s strength makes it more likely to survive.
Can motorcycle chains be repaired roadside?
One solid advantage of a chain drive conversion on your Sportster is that motorcycle chains can sometimes be repaired or even replaced roadside. Generally you’ll want to have a motorcycle chain master clip and pins that fit your sized chain, and a couple wrenches. You can’t repair a chain from every type of damage, but there are some things that you can fix roadside with relative ease.
On a belt drive things are a little different. You can’t safely repair a belt that’s damaged. You would have to have with you not just some wrenches, but also a spare belt, to make a roadside repair possible. In other words, roadside repairs are more possible with a chain.
What can we do with Sportster final drive ratios?
One of the reasons to consider switching to chain drive are the endless possibilities of final drive ratios. That’s because chain sprockets are a lot more widely available and in-stock than belt pulleys, due to how much more popular chain drive is.
You can change motorcycle chain sprockets to adjust the final gear ratio. Final drive ratio effects your motorcycle’s torque and horsepower. A lower final drive will make less torque at the rear wheel but give better top speed. A higher final drive ratio will make more torque at the rear wheel at the cost of greater top speed. It all depends on what land speed record you’re going for: top speed, or acceleration.
Gearing-Commander is a website dedicated to showing riders what the effects of their gearing ratio changes can have on their motorcycles. Sprockets of different sizes are very easy to source compared to the pulleys that belts run.
If you’re into customizing your gear ratios for specific purposes, like racing or setting a land speed record for either acceleration or top speed, this is excellent. Realistically, most Sportster owners aren’t looking to set any land speed records. If you aren’t likely to ever take your Sportster to the track, messing around with your final drive ratio is probably redundant.
Does a chain drive conversion weigh less than belt drive?
A chain drive conversion will save a few pounds over a stock belt drive setup. Despite a chain weighing more than a belt, the pulleys a belt runs on weigh much more than sprockets. The net difference is a few pounds saved.
This is one area that’s a clear win for the chain drive conversion, although a rider could always just lose a few pounds and save themselves the cost of converting to chain drive.
Does a chain drive conversion make my Sportster faster?
There is a belief that converting a Sportster to a chain driven final will give better performance. This is circumstantial at best, and it depends on what kind of performance you’re looking for. As mentioned, you may save a few pounds, cutting our beer for a month would give you the same result too.
What even is “faster”, anyway? Are we talking about acceleration, or about all-out top speed? Either way, your final drive ratio will play a bigger role than your final drive type in determining your motorcycle’s performance. Your motor isn’t too concerned with whether it’s turning a chain or a belt to spin the back tire, what the ratio of the pulleys or sprockets are will play more of a role.
5 Advantages of keeping belt drive over a chain drive conversion on a Sportster
Chain drive has many advantages over a traditional Harley-Davidson belt drive setup. Several of the advantages aren’t substantially beneficial to most riders though! There are also some key advantages to belt drive over chain drive including ease of maintenance and longevity. Let’s take a look at those.
How long does a Harley-Davidson drive belt last?
It’s not unusual for a Harley-Davidson drive belt to last over 60,000 to 100,000 miles. If properly tensioned throughout their life, a drivebelt can last the lifetime of a motorcycle. This isn’t to say that drive belts never fail. Any time there are millions of a product out there, thousands will fail, unfortunately. Often though, drive belts are known to be a set-it-and-forget-it item that you only check on every oil change.
That brings the question of how often a motorcycle chain lasts. There are many variables including chain type and maintenance schedule. Generally, a diligent owner with a well-cared for chain could last 10,000 to 15,000 miles. A less diligent owner with a more relaxed chain maintenance schedule could get as little as 10,000 km of life from the same chain.
What is maintenance like on a drive belt versus chain drive?
If your Harley-Davidson drive belt was a house plant, it would be a cactus. You could almost forget about it completely, and it would probably be just fine. You set the tension and you can forget about it for several thousand miles. Most riders will simply check it out every oil change and rarely need to adjust it.
Your chain’s house plant equivalent is an orchid. You’ll notice a big increase in routine maintenance after a Sportster chain drive conversion. Chains have a reputation for being high maintenance, and for good reason. They need to be checked, cleaned, lubricated, and adjusted, repeatedly, forever. Most riders will check their chain every time they fill up their tank, and clean and relubricate the chain every two fill ups. By being diligent like this you can go 1,000-2,000 miles between adjustments. However, those who are less diligent about cleaning and lubricating their chains could end up needing to do chain adjustments every 800 miles or so.
It’s important to know that chain wear isn’t just a product of how much you’re riding, and how well you’re cleaning and lubricating your chain, but also of how you’re riding. For example, if you’re aggressively on and off the throttle, it’ll stretch out your chain a lot sooner. The takeaway is that belts are much less maintenance.
Is belt drive cleaner than chain drive?
Belt drive is very clean compared to chain drive. Belt drive doesn’t require any lubrication which can fling everywhere, or any cleaner which can spray or drip everywhere. Neat freaks who keep a clean machine might want to shy away from a Sportster chain drive conversion.
Chain drive is messy. You can buy more expensive chain lubricants and cleaners to help. You can also clean and lubricate your chain after your rides instead of before to try to help. Ultimately though, all of the products you’re adding, being spun at a hundred miles per hour, are going to fling and create some mess. That’s not something you have to worry about with belt drive, which gives you a cleaner more modern look.
Is belt drive smoother than chain drive?
Belt drive is smoother than chain drive because belt drive has less driveline lash. Driveline lash is a jerky feeling when you’re going from on the throttle to off the throttle, and vice versa.
Belts tend to be smoother and quieter than chains for several reasons including no kinks in a belt like you can get on a chain, and less play on a belt as on a chain. Belts are arbitrarily more likely to be within spec compared to many neglected chains on the average rider’s motorcycles.
What are some other considerations?
- Belt drive may be safer than than chain drive, in that a breaking chain is known to cause damage and injury, but there are very few reports of damage or injury from a broken belt.
- It would cost less to replace a belt just a belt, than to switch over to a full chain drive conversion kit.
Sportster Chain Conversion Conclusions
For people putting a lot of money into their motorcycle’s motor looking for track level performance, this Sportster chain conversion kit would make a lot of sense. For other riders, who care more about the look than about performance, a chain conversion will make their motorcycle look more traditional and allow them to fit a fatter tire. The cost is a lot more maintenance.
For the practical everyday motorcyclist, there are a lot of utilitarian benefits to sticking with the belt drive. Is it the most efficient final drive? No. But there is little to no maintenance, you don’t have to clean up after it, and it is likely to last you longer than you’ll keep your motorcycle for.
At the time I did my belt to chain conversion the belt was only marginally cheaper than the chain conversion.
This was back in 2005. 200 USD vs 184 USD and either one had to be ordered. In the. long run a belt may be cheaper (if it doesn’t break) as most folks get 2 chains out of every set of sprockets before new sprockets are required. which could be anywhere from 60,000 miles or more if the chain is taken care of religiously. Also a chain does not/rarely break if taken care of properly.
MOST IMPORTANT!!!!: Do NOT cheap out on the chain as it will not last as long as a good reputable brand and it will eat sprockets up like they are candy! And run a sealed chain whenever possible )-ring, X ring, W ring, Z ring doomahickey ring whatever as long as its a “sealed”chain. Lasts longer. You can run a standard chain in a pinch and they may be cheaper but last only half as long (if you’re lucky) as a sealed chain.
All in all its a matter of preference.
Well said. If you plan on keeping your motorcycle a long time, a cheap chain is a luxury you can’t afford. Better to get a quality one and pay a little more up front. if you take care of it you’ll be very happy.
Will a 136 teeth belt fit on a 137teerh is required to be
I would just get a kit (like this one: https://amzn.to/31Hqsbe ) where everything you need comes in one kit so you aren’t having to worry about whether or not everything is going to be compatible.