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2011 RaceTech Suspension Upgrade Review

by Jeff on June 27, 2011

We evaluate RaceTech’s high-performance motorcycle springs, Gold Valves, and personalized tuning and rebuilding service.

By Jeff Cobb
Motorcycle Safety News

Any rider who wants more safety, control – and fun – can easily benefit from suspension tuning for his or her body weight and riding style.

This is true whether you buy a new motorcycle, have had one for a while, or acquire a used bike. It also applies regardless what kind of street or dirt bike you ride – you will be happier if your suspension is dialed.

A lot of bikes – from brand new to quite old – can be made to ride and handle better than new.

Recently this point was brought home to me when I sent the stock forks and shock from my ’98 Yamaha R1 to RaceTech in Corona, Calif. for a complete overhaul with new springs, seals, bushings, oil and custom valving by way of RaceTech’s Gold Valves.

What I got back made my bike feel better than new because it was now custom tailored for me, which I will tell you more about shortly.

Why RaceTech?

Stock bikes are a compromise. Depending on adjustability, you may be OK with stock, but if you are lighter or heavier than average, carrying a passenger or extra load, or looking for more control and safety, some degree of custom tuning may be well worth it.

Many have heard of RaceTech, but in case you have not, the company founded in 1984 by Paul Thede is one of the original motorcycle suspension innovators in modern times.

Former motorcycle journalist and advanced motorcycle skills trainer Lee Parks says of Thede, “Paul has forgotten more about suspension than most people will ever know.”

I know Lee from taking a few of his classes in California. He is highly skilled and somewhat of a quality control maven himself. He also co-authored RaceTech’s Motorcycle Suspension Bible with Thede, and I know he is careful in his word choice, so his endorsements mean a lot.

Control and safety

Although your safety will be enhanced when your tires properly track what ever pavement you ride over, so will your control.

Suspension performance and safety are actually opposite sides of the same coin. While sometimes overlooked, suspension setup can be worth more than extra horsepower.

Yes, you read correctly: if offered the choice for 5-10 more horsepower or a dialed suspension, I will take the dialed suspension every time.

Disassembling a cartridge fork.

Most riders understand upgrades like bolt-on exhausts, ECU or carb tuning, intake tweaks, etc. – but what is the point of all that go-power if your suspension cannot manage it?

This is true on the street or track for any size bike. A supple suspension will let you put more power down everywhere. It will also enhance your confidence, and we all know the value of a mental edge.

This helps on the safety side of things as well. Even if you take great care, if your suspension bottoms, wallows, is poorly damped, your chances are greater of one day being caught off guard.

The need

My ’98 R1 is a clean, well-tuned machine. I love the bike, but the suspension was ideal for someone weighing maybe 140-150 pounds or so, and I weigh about 185 pounds (about 205 pounds with gear) and ride aggressively.

As such, I had my front and rear spring preload set stiff to try to compensate for under-rated springs, and inadequate compression and rebound damping settings.

RaceTech uses straight springs for most applications. Air volume in the fork compresses to create a progressive effect. Increasing oil level increases progressiveness and vice versa.

RaceTech has found external damping in some cases make less than a 3-percent difference. They are good for fine tuning, but depending on your situation, you may need as much as 200-percent damping changes.

The set-up

Basically, I got the top-of-the-range on this Web page showing parts and service options for my older R1.

Possibly the single most important thing for me was getting the correct front and rear spring rates. What this did was level the load front and rear without needing to jack the preload up.

RaceTech uses high-quality silicon steel, shot-peens and heat treats every spring to stress-relieve it. The result is light but durable, and every single spring is tested for spring rate accuracy that will not “sack” like a stock spring can.

Perhaps second most, if not equally important, was the installation of RaceTech’s Gold Valves in my cartridge-type fork. These replace the stock piston with larger tunable ports that allow dramatically more oil flow and reduce harshness for a more plush ride.

A typical “upside down” cartridge fork. Besides this style, RaceTech tunes all kinds of suspension.

In fact there is interplay between compression damping rates and spring stiffness. Having a balanced system is key to creating the ride you want.

RaceTech’s newest G2-R Gold Valve was used on the fork’s compression damping side and original Gold Valves were used elsewhere. My old bike did not have the G2-R spec available for front rebound and rear applications. RaceTech’s original Gold Valve is still a huge improvement over stock, and it keeps these on hand due to popular demand.

The Gold Valves uses a “shim stack” of high-tensile flexible shims that are stackable in any number of combinations to allow just the right oil flow under certain load conditions. There is a lot to this, but in short, by making the stack stiffer or less stiff, a tuner can adjust the flow rate to fine tune the ride much better than stock.

This graphic shows Gold Valve shim stacks – the shims bend with damping movement.

RaceTech’s computer generated Digital Valve System is used to custom tune an individual bike according to actual bike and rider weight, level of expertise, how he rides it, and more. Thousands of variable combinations are considered which is why this service is so valuable.

Click picture to enlarge: These are the spec sheets RaceTech returned for the R1′s Digital Valving System setup.

The end-goal is a combination of plushness and bottoming resistance as needed.

While RaceTech was at it, the tech replaced all the wear items including bushings, seals, bump-stop, and replaced the shock nitrogen bladder with an over-sized one, and used its own synthetic oil.

The ride

Upon re-installation, I soon noticed my headlights were now pointing lower which means my old rear spring had been letting the bike squash under my weight even though it was fully preloaded.

With RaceTech’s new straight-rate springs, I was finally able to achieve correct ride height, and it was no hardship to adjust the lights.

This gave me more cornering clearance also, although that will only help on the track for this high-clearance bike.

Note replacement nitrogen reservoir and cap. Original springs were yellow, by the way.

One thing I did first was set front and rear sag to 32 mm. With the help of a friend, we had to turn up front and rear preload a little bit, but the new stiffer springs did not need nearly as much preload much as before.

RaceTech had set the compression and rebound settings where it had thought I would like them, and they were right on.

Measuring fork oil level.

Riding down a flat road there was naturally little difference to be felt, but the second I hit any kind of bump, the difference was immediately noticeable.

Essentially small cracks, sharp edges, manhole covers and railroad tracks were absorbed with more plushness.

Getting the feel for the bike, I began exploring back country roads, and looking for corners. The bike feels so much more planted, like a rolling scalpel that lets me place the front wheel on any line I want.

In riding over rougher surfaces, compression damping is controlled, and the system rebounds back on time adding to a more confidence-inspiring experience.

Tuning a freshly rebuilt fork.

A few times I found myself on roads bombed out so bad they should have been dug up and replaced. On the East Coast, frost heaving and low state budgets do nothing for some road surfaces that wear out and are endured by car and truck drivers, but which can be a real hazard for riders.

Naturally I did not fly like a banshee through these sections, but no where have I bottomed out hard. Previously, the stock suspension would bottom hard sometimes. Ironically, it had been harsher with the softer suspension.

I have not yet track tested the bike, but it was set up with track days in mind. I am absolutely sure this bike will be better at high speeds as well.

Overall, my bike handles highways, secondary roads – every road – with more control. It is more confidence inspiring knowing my tires are tracking and the experience has made a good bike even better.


RaceTech has a saying: “The best you’ve ridden is the best you know.”

With this I have to completely agree.

After having experienced what can be done even with stock suspension, I will never go back to owning as-delivered stock suspended bikes again.

If you are on a budget, you can do less than a complete overhaul. Aside from in-house service, RaceTech also sell springs and kits for do-it-yourselfers, and offers any level of tech advice via phone to help decide what you may really need.

RaceTech has engineered higher-tech solutions as well, such as its GS-3 totally built-for-you shock and G2-R drop-in replacement kits for cartridge forks. It has a fix for a staggeringly broad range of street and dirt bikes.

For street use, optimizing stock pieces will almost surely be more cost effective, and potentially better than installing some aftermarket high performance suspenders. If one did get another brand of aftermarket shock and fork, it might still have to be completely dialed in.

Optimizing your existing suspension makes it quasi-custom, and improves safety and control. If you have an older bike, or one with uncertain history, it could very well already be due for service.

Even new bikes can also benefit. Anytime is good for these improvements, or if your bike is due for normal service, that would also be ideal.

Sending your suspension to RaceTech or one of its authorized service centers can be better money spent than on something like a new exhaust; they can service and improve vital components, and add performance all at the same time.

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