The basic set up: New progressively wound Hagon springs, and one liter of fork oil.
OEM suspensions generally work fairly well, however, they are designed (and priced) to perform within certain parameters, and once you exceed those parameters, as we all do from time to time, handling and comfort can get a little wonky. They are also subject to normal wear and tear, so in time, springs sag, shocks lose their damping and before too long your formerly fine-handling cruiser has become the world’s fastest mattress. Fortunately, most suspension issues, whether caused by design or deterioration, can be resolved without bottoming out your wallet or your weekend.
Choosing the right components
An ounce of prevention is...
An ounce of prevention is worth a trip to the paint shop any day.
Selecting the right springs and shocks is the first order of business, and the choices can be daunting. Fortunately, every suspension manufacturer has a catalogue that provides specific recommendations along with the available options and prices.
Prices vary greatly, and for many of us that’s a prime consideration. For example, shocks for the Triumph Bonneville range from Hagon’s no-frills Classics at $199, to the high-tech Öhlins Type 36PL at $899.95. What’s the difference? The Hagons are a basic spring preload-adjustable shock; they work very well, are solidly made, and will noticeably improve the handling of your motorcycle, but they’re not fancy. The Öhlins have all the bells and whistles, including an adjustable ride height provision and adjustable rebound and compression damping, as well as being re-buildable. They also look expensive, which is a consideration to some. That being said, I’ve used the Hagon Classics on everything from the bike in this article to my vintage dirt trackers with excellent results. The bottom line here is that even “affordable” shocks offer a substantial improvement over the OEM versions, so there’s no need to bust the bank.
Cost aside, what criteria should you use? As someone famous once said, “If you want to know what works, look at what the guys on the podium are using.” In this instance, you might want to check out internet forums and see what shocks and springs are most popular for your brand of bike. If everyone riding a Yamaguchi swears by Sag-No-More shocks, it’s a safe bet they’re the hot setup for your Yamaguchi ThunderThigh 1200.
I’d also recommend contacting the manufacturer’s tech line. In fact, some manufacturers won’t ship the shock until you do. They’ll help you select the correct spring rate and shock length and answer any technical questions you might have, greatly short-cutting the selection process.
Loosen the axle nut before...
Loosen the axle nut before lifting the bike.
Loosen the upper clamp bolt,...
Loosen the upper clamp bolt, then loosen the fork nut.
Make sure the bike is firmly...
Make sure the bike is firmly supported before removing the front wheel, and forks.
Remove only one fork leg at...
Remove only one fork leg at a time.
Everyone’s spring kit is slightly different. Some include any new pre-load spacers you may need but some don’t, so read through the installation instructions before opening your toolbox. It’s one thing if new spacers aren’t required and another if you have to run out halfway through the job to buy a hunk of PVC pipe to fabricate them. Likewise, check the fork oil specs; you’ll need at least a quart and possibly more, so make sure you’ve got the right stuff before you disable the bike.
The basic procedure requires draining the fork, removing the old spring(s), installing the new one(s) and refilling the forks with oil. If you’re riding an older bike with fork drain screws you’re way ahead of the game, and you’ll be able to do the job in an hour or two without removing the forks. Most of us won’t be that lucky, and will have to remove the forks to drain them.