Some Questions about the S4RS

[Timmy Tucker]

Hi all,

I just pulled the trigger on an S4RS and have a few questions about it. My previous bike was a '99 M750 that took a massive electrical shit on me 5 years ago. Life got in the way and I never got my old Monster running again. I also haven't really ridden at all since then, maybe 1-2 times a year. When I quit riding, I was kinda bored with the M750 and was wanting something bigger. I'm picking the S4RS up this weekend, but won't be able to do anything with it for a few weeks due to my work schedule. Thus, I have a few questions...

Assuming both suspensions are still set up stock from the factory, is there a big difference in feel and/or handling between the two (aside from the extra HP)?

The gas tank is not swollen. Is it safe to assume that if it hasn't done it by now, that it probably won't? Also, I remember someone here was working on a metal tank for them years ago. Did that ever come to fruition? Are there any other tank replacement options?

Any other gremlins to be aware of? Also, are there any must-have mods?

What's hot for tires right now? I always ran PR3's due to the bike being used for both twisties and quite a bit of travel. The bike won't really be used for travel anymore, so I think I might prefer a sportier tire.


Thanks in advance!

(Also, I'm sure you guys don't remember me, but I used to hang out here (and the old board) a little about 8-10 years ago. Hope you guys have all been doing well!)

[koko64]

Welcome back

I would recommend a Michelin Road 5 up back and a Power RS up front. Or if the miles are real low each year an RS at both ends.

[Speeddog]

Stock S4Rs suspension is better than stock M750, but well short of it's potential.

Gas tank will swell, the only thing I've correlated with reduced swelling is keeping it full when the bike sits.
Some folks have had success with coating them.

The only metal tank that's worth getting is an aluminum one from Beater in Japan.
It's a rare case of getting what you pay for, in a good way.

They run hot enough and the packaging is tight enough that the VR's tend to die.

I'd recommend some less grabby pads for the front brakes, there's plenty of power and milder pads treat the rotors better.
Footpegs are kinda slippery.

Get the shock revalved.

[Howie]

About sums it up.  Regulator can be moved (pretty big mod) or Mosfet regulators work better.

I like the Bridgestone S21.  Good turn in, resists squaring off.  Only thing is it is now replaced with the S22, which  I know nothing about.

[Timmy Tucker]

I didn’t know that the VR’s were an issue. I thought that was only a problem with the older bikes. I’ll change that out asap, as that’s what happened to my m750. Damn thing went out on a road trip across the state and took a big chunk of the electric system with it.

[Howie]

Actually, my old 750, sold to a friend a few years ago with 8?K miles still has the original regulator.  The problem with the newer bikes is it is under the seat, out of the air stream.

[S21FOLGORE]

Yup. Happened to me (2005 S4R), and that's the only time I got stranded on my bike.

[Timmy Tucker]

Actually, my old 750, sold to a friend a few years ago with 8?K miles still has the original regulator.  The problem with the newer bikes is it is under the seat, out of the air stream.

Mine was somewhere around 35k. And it left me stranded more times than I could count. Once it got up to temperature, if I got in stop and go traffic or stopped without letting it cool down completely, it would vapor lock and stop running for about 45 mins. Happened several times a month.

[Moronic]

Speeddog and Koko have the lowdown, from my perspective.

My sig line links to a thread on here with my experiences setting up the suspension. I worked with Rick at Cogent Dynamics, but I've no doubt other shops could help.

On tyres, I've used the PR3s and several sets of the previous sportier Michelin, the PP3, which I loved.

Now have Michelin Road 5s at each end and am very happy. Longer life than the PP3 and similar steering, through a carcass that seems a bit stiffer but for the street still offers plenty. Interesting idea to run the sportier Power RS up front, since the weight bias seems a bit light on the front and I'm told the profiles for Power RS and Road 5 are the same. Steering on the Road 5s feels way sharper than on the Road 3s, which felt somewhat truck-like by comparison with the Pilot Power or Power 3.

Couple of extra bits that might help.

I've fitted an aftermarket cable kit from the battery, and added a second earth point. Starting became much more immediate. And you really don't want to push-start these things: they will lock the rear tyre in second gear, so you need third and a hill.

Extending the rear suspension linkage four turns helps the steering. Stock mine tended to run a little wide, which you can sort out with body position. Kicking up the rear a bit leaves her neutral with your body in line.

Stock preload adjustment on the shock was via twin lock rings, one of them nylon. The nylon ring on mine cross-threaded, either because it came that way or because couldn't compress the spring with weight on the tyre. Doing the adjustment with Ohlins C-spanners is painful - with care, you can get about an eighth of a turn done for each engagement of the spanner. Adding a hydraulic adjuster is a great mod, and the stock spring should be short enough to leave room for that - it's the same length as the spring that comes with the aftermarket Ohlins DU 333, which has a hydraulic adjuster.

The throttle position sensor on mine went bad, and the diagnostics won't show that. Symptoms are rough running at steady throttle and poor fuel consumption. Replacement is a bit tricky and I won't go into detail here - with any luck, yours will be fine. Just a heads-up.

Mine went through two radiators in about 30,000 miles. The left mount connects with the core at the upper tube, and they develop a fatigue tear. Symptom is white deposits from coolant blowing back onto hoses etc on that side. A shop called Race Radiators in Dandenong, Victoria, Australia, can repair them cheaply and very effectively.

In stock form the front mudguard - fender for you folk in the US - will strike the bottom of the radiator on full compression of the front suspension. Ducati's fix was to add some fluid to the fork, reducing the air gap. That's worked for me.

Use the proper Ohlins fork fluid when replacing seals, for best performance, and replace the lower bushes as well, which will extend the life of the new seals.

One of my favourite mods has been a more comfortable seat, from a custom builder.

Set up right it's a spectacular bike. I've had mine since new, and at 60,000 miles I lust after no other ride. The S4Rs satisfies on so many levels.

[JonS2R]

The gas tank is not swollen. Is it safe to assume that if it hasn't done it by now, that it probably won't? Also, I remember someone here was working on a metal tank for them years ago. Did that ever come to fruition? Are there any other tank replacement options?

S2R owner here with the same kind of plastic tank. I've had my bike around a year and use ethanol free gas almost exclusively and it has no issues.

[dbran1949]

S2R owner here with the same kind of plastic tank. I've had my bike around a year and use ethanol free gas almost exclusively and it has no issues.

I'm on my third tank. I had this one coated and so far it is holding up well. The consensus is that the ethanol absorbs water, and it is the water that deforms the tank. so if you are lucky enough to find fuel without it you are better off. My only issue with the bike is that will the full Ducati DP termi kit, pipes and ECU. I can only get about 75 miles on a tank. It means i have to plan my rides carefully. But nothing beats that feeling of that front wheel getting lite in third gear

[Timmy Tucker]

Thanks for all the advice! I picked the bike up this weekend and now I have I have about 2 million more questions.

I'm super happy with it so far, it's in better shape than I thought and has lots of aftermarket bits. I can't wait to ride this thing.

[koko64]

Very nice. Good score👍

[Howie]

Looks great. Love the exhaust.    and enjoy!

[Heath]

I didn’t know that the VR’s were an issue. I thought that was only a problem with the older bikes. I’ll change that out asap, as that’s what happened to my m750. Damn thing went out on a road trip across the state and took a big chunk of the electric system with it.

Mine went out on my S4RT and took out the gauges and an aftermarket chinese headlight (that was actually a blessing). Be sure to upgrade that to a MOSFET unit if it hasn't been done already.


Moronic covered a lot of what I have went through too.

I had a Timing sensor go out which caused a lot of issues starting. It bench tested fine but failed a test under an oscilloscope.  Unfortunately for me the shop didn't have one and it took them forever to find one to borrow.

That exhaust is awesome, I want to hear it!.