Modern Vespa

Has anyone any experience of the Kubler Speedring? I’m contemplating having one fitted at the first service but would like feedback from anyone who’s got one fitted or experienced riding with one fitted.

Few that have it like it. I have one sitting on the shelf to be installed at the first rear tire change.

Edited so it makes sense
Damn I need to reread before hitting submit.

Last edited by WEB-Tech on Wed Jun 24, 2020 9:46 am; edited 2 times in total

You can use the search function to find previous MV discussions here,

Robot video Increase Top Speed to 85 MPH
http://modernvespa.com/forum/topic169374

Kübler speedwheel (+10 km/h) for HPE - anybody tried it yet?
http://modernvespa.com/forum/topic166917

New Product From Germany Increases Speed
http://modernvespa.com/forum/topic166512

I finally installed mine last night. But I have yet to use the scooter today. And I found that Robot's video about torching the wheel wasn't necessary to remove the factory ring. Must be the Super's problem.

+1

Thanks for the links chaps. As I’m undecided I’m leaving it. I’ll see how the scooter performs when I can finally open her up after the service and take it from there.

Higher top speed is nice, I am getting for the speed-o correction myself.

and the lower odometer recording also.

I had mine installed by Robot when I bought the scooter, so I don't know what it would be like without it. I prefer to know the actual speed when I look at the speedometer. The top end power might be nice once I get used to the machine and feel comfortable going faster than 50 mph.

Seeing the actual speed as opposed to Vespa speed is a massive bonus, fair point.

Jim, did robot explain that it voids the warranty on your brand new scooter?

I have two of the sitting here, one for each scoot and they will go on with the next tire change. Not an HPE but I bought them for the speedo correction promised. Can you explain to me why you think it would void the warranty?
Magnauson Moss Warranty Act allows you to use third party parts without voiding your warranty. https://www.bing.com/search?q=magnuson%20moss%20warranty%20third%20party%20parts&qs=n&form=QBRE&sp=-1&pq=magnuson%20moss%20warranty%20third%20party%20p&sc=5-36&sk=&cvid=42270E0173894D8595640582F20D6316

According to the FTC, using aftermarket or recycled/re-manufactured parts doesn’t void a vehicle warranty. The Magnuson-Moss Warranty Act makes it illegal for companies to void a warranty or deny coverage under the warranty because an aftermarket or recycled part was used.

In Robot's tire change video he actually mentions that it doesn't: https://youtu.be/Ux6cLiy2buo.

The change only adjusts the speed reported to the system and doesn't affect any other operating parameters. So it's hard to understand how it could affect the warranty directly.

Yeah but your gas mileage is going to suffer.... (just kidding) I have one I'll install on my first rear tire change as well.

Odometer doesn't seem to be affected by the inaccurate speedo.

Interesting. I would guess then that the odometer is controlled by the number of holes in the ring and the speed display is a function of the hole size (pulse width as the hole passes the sensor). I assume the number of holes is the same in the new ring, they're just a little larger (or smaller).

I was quoting my dealer up here in Santa Rosa who told me it would void the factory warranty. I think he might be misinformed, but I'll probably wait until first tire change.

The reality is that there's not alot of information about this ring change that we really know. Likely because it was reverse engineered.

But I can state that the Kubler ring has 44 slots, and the original Vespa ring has 48. So it's most likely just a function of the number of slots. However when you lay the Kubler on the Vespa ring you will note that some of the slots are offset in a way which is unclear to me.

I'll generate a 3d print that is more regularly spaced at a future time, and try that to see if that works as well. Plus I'm also interested in dropping the number of holes to 43 for a 10% decrease (as a test), rather than the 8% as it is now.

What they said: If I filed a warranty claim that was a product defect because of or closely associated with the speed ring, the warranty would not cover it. Every other kind of defect would be covered.

If I file a claim based on a defect of the Falco folding luggage rack, the Vespa warranty would not cover it. Likewise, any problem caused by or closely associated with any modification or an aftermarket product installed on the scooter would not be covered by the Vespa warranty.

Not in the US. Manufacture would have to prove the replacement tone ring caused the problem. And just changing a tone ring, it would be REALLY hard to prove it caused a problem.

And if you didn't tell the servicing dealer, how the hell would they know, it looks EXACTLY the same as the OEM one?

Find another dealer if you can, HATE dealers with the IT will VOID warranty attitudes.
What is a tone ring going to change that would void the warranty? IT can't change the air/fuel mixture. All it does it work with the ABS and tells the speed-o how fast you are going. Has no affect on how the engine runs.

It's no different than putting a larger diameter tire on. Will the manufacture void your warranty for a larger a tire?

I also changed my HPE over to this speed ring. It did three things:
1) It fixed the speedometer so it now displays the speed accurately.
2) Increased the speed limiter speed to ~85 mph.
3) The odometer now shows mileage that is 7.5% lower than actual.

I have installed it on a 2020 GTS 300 HPE with 13inch rims
still testing it
up to 80kph was running in parallel with the gps
at full gas it was stuck at 105 kph the gps was showing 126kph
had to stop it was a windy day
wondering if the 13" rims give crazy readings

What tires do you have? Did your ABS get recalibrated when it was installed?

front 120/70/13. rear 130/70/13
yes I did the recalibration procedure

The thing is, it can causes the bike to over rev which could potentially cause damage to the motor. Top speed of the bike is 75mph. With the ring it's more because the motor revs higher and beyond what the manufacturer designed it to do. Yeah, I know there is built in redundancy to some extent but that gets eroded over time as you use that performance more and more. That's why it will invalidate your warranty in some circumstances. It is a modification to the bike that is not factory approved. It's not the same as using after market service parts. Personally, I'd go for it, but with the understanding of the above.

I'm certain the rev limiter is not affected by the Kubler ring, only the speed limiter. If the variator has reached its limit at the speed limit, then extra speed will come at the expense of higher revs, but then the rev limiter will still protect the engine. Anyway, higher revving could be offset by using heavier rollers.

For the Kubler ring to affect the rev limiter, the engine would have to be calculating the wheel speed, gear ratios and variator belt position to work out the engine speed. But it has no way of knowing the belt position. So I don't believe the ring makes any difference to rev limits, only speed limits (and odometer readings).

The ECU knows how often it is firing the spark plug and the injectors, so it doesn't need any other device to tell it the engine revs.

As usual you say it simple direct and right. That’s also why I won’t install it on my racing sixties. I read that the new HPE already revs higher than the former for a same speed. Want to it keep for long.

Are these just for the HPE or can they be installed on the rear of any GTS with ABS?

I believe on every vehicle you must be prudent and understand the limits of it.
Full throttle constantly will break any engine.
For me the extra 10kph is needed to overpass safely a truck for example, maintain safe distance and return to the normal operating speed.
The vespa has a limiter of 120kph for stability reasons.

On any pre-HPE ABS GTS it will just make the speedometer more accurate. No performance benefit.

Does anybody else have experience of fitting?

I've got mine arriving tomorrow. Going to fit to a 2020 Touring. If others have needed to heat the rim then I'll probably pass it onto the guy who will do my first service - otherwise I'll pop it on when I change the exhaust.

I've done 2 so far, quite easy once you get access to the ring.

I've found that you can't always rely on what Robot mentions. So I have no idea where he came up with that flame thrower idea.

I think you need to analyze this over-rev idea a bit more. It doesn't make any sense that the ring itself is going to put the engine into an over-rev situation; one for instance that a long fast downhill ride, without a Kubler ring, would somehow have a similar potential to do using that logic.

Certainly though, a dealership if they notice it could deny you warranty repairs because it's not factory standard. But to suggest it's going to allow the engine to always over-rev isn't considering all the design data.

It never seems to me safety wise to be all that smart to be pushing along at a high speed anyway. I prefer anything under 50 mph much better, even though the scooter does well enough at those faster rates when required.

It's more dangerous here to not know your actual speed and thus going slower on the roadways than the traffic wishes. Having a better direct read-out on one's actual speed is an improvement that the tone ring provides.

I plan to have my dealer fit one at my first GTS300HPE service - it was his suggestion, mostly for speedo accuracy. I understand (on advice and a little web sleuthing) that the ring only affects the speed limiter, and speedo - ABS etc will adjust, and the rev limiter is separate.

I'm still running mine in, but have found the motor seems to run out of puff at indicated 120kph/75mph (probably 110kph actual), which seems to be the speed limiter.

My reason is to be able to briefly exceed that speed - particularly on freeways. I don't often ride on 110kph speed limit freeways (our city freeways are 100kph max), but when I do the ability to get out of trouble with (e.g.) drivers on cruise control at just over 110, and trucks sitting bang-on 110, sometimes requires a spurt of speed. At little more speed for overtaking on two-lane won't go stray, either. I don't want or need to ride at 120kph for any extended period.

And the accuracy won't hurt around our multiple speed limits ..

Ignore his advice at your own peril. Clearly he's encountered screws that were red loctited in. It can be almost impossible to remove them without stripping, or even breaking off the heads. Yours must have been made on a Friday when they were in a hurry to get to the bar.

Heat (via torch or air gun) is a tried-and-true method of loosening up the grip and making them easy to remove.

Hi bosco, nice to talk with you. I understand where you are coming from.

Yeah what I am saying is if the engine is going past the 75mph mark the engine is over revving and going past the engineers designed speed. The rev limiter is preventing the motor going faster at 75mph because the design engineers have altered the rev limit ceiling so it's lower. Lower than on the earlier motors. Earlier motors have the rev limiter coming into play at around 81-83mph indicated (I've seen both those speeds trigger the rev limiter) and it will vary from bike to bike due to lots of variables. On the HPE they have done this to maintain long term mechanical reliability. This is needed when you produce a mass produced engine with substantially increased power based upon an older design (although it's perfectly good to do this). Don't forget the HPE has 18% more torque (the engines actual power) and 12% more horsepower (a measure of how quickly the engine can produce that power). That is substantially more than the euro3/4 motors. But it comes at the cost of less top speed to protect the motor.

If you fit the ring it fools the ecu into thinking you are going slower than you actually are so it continues to let the revs build and therefore the bike goes faster. The gearing of the variator, belt position etc etc is not affected and cannot be affected by the ring. The HPE is running in it's highest gear position at 75mph so the only way it can go faster is for the motor to rev past it's designed set speed as set by the design engineers. This means it is over revving, the rev limiter speed restriction has been raised.

I've not had the HPE on the dyno yet or seen one being dyno'd and I haven't had the chance to take one flat out yet, but I bet at 75mph the motor seems to tighten and then doesn't want to go faster. That's because the "Rev Limiter" is reducing fuel to the injector and retarding the ignition. It also eventually probably starts to cut out shortly after in bursts to let you know to back off the throttle to prevent engine damage. The rev limiter on the HPE is much more subtle than on the earlier bikes which almost straight away go to engine cut out mode. That's how rev limiters work. There is no speed limiter as such, only the rev limiter. Folks often confuse the two. Trucks have speed limiters and these can work a bit differently and can even apply the brakes to maintain the correct speed even downhill.

Fitting the ring! It's a bonus if it makes the speedo a bit more accurate, but you should take that with a pinch of salt as it's impossible to make a completely accurate speedo for everyday use because of all the variable that affect speedos and talked about endlessly in other threads. But no doubt it is more accurate but at the expense that you may end up going faster than the speedo is registering because you have lost the under read safety zone specified by manufacturers.

That said and as I mention in an earlier post, I don't think the ring will do any actual harm if one is not using that top end performance too regularly. I'd fit one if I had the HPE, but then maybe I wouldn't. Little point in my opinion. If you want to go above 75mph on a regular basis, get a bigger bike!

Hundreds (thousands?) of GTS owners have fitted the Malossi V4 kit which makes their scooters slightly more powerful than the HPE. Hundreds have also fitted the Malossi ForceMaster ECU override which pushes the rev limit up by another 1000 rpm.

I have never heard of any problems caused by over-revving as a result of these mods.

Stromrider - I generally find your posts about engines to be interesting and thought provoking. I’ve been building engines and transmissions (and a host of other things) since the early ‘80’s and am a six time certified Master Tech, though no longer professionally. Based on that, unless design engineers at Piaggio have specifically told you the speed limiter was put in place because the engine can’t handle higher revs i think your post is highly speculative. As you know, even with the Kubler ring installed the engine still has a rev limiter. It is not reliant upon the speed limiter to protect the engine from over rev. Furthermore, due to variance in RPM at any fixed speed based solely on throttle input and angle of climb or descent (characteristics inherent in the CVT design) attempting to protect an engine from over rev based on vehicle speed instead of engine speed would be both ineffective and silly.

I’d like to see some proof to back up your theory. Otherwise I remain convinced the speed limiter has nothing to do with engine protection, and has more to do with the fact that large frame Vespas have always had a top speed in the neighborhood of 75 mph. Realizing this version had enough power to go significantly faster Piaggio programmed in a speed limiting function.

Piaggio has decided that as a mass produced scooter engine that is often ridden flat out by it's owners, the HPE engine is at risk if it is allowed to rev out to the same extent as the lower powered euro3/4 GTS bikes. So giving it more power, but lowering the rev ceiling to make sure of avoiding problems down the road is quite normal. I've done this myself when revising and developing some types of engine designs for manufacturers. This is quite common. Manufacturers don't want their bikes to get a bad reputation for unreliability. I haven't checked the final drive gears to see if they are the same as the previous bikes but even if the HPE has the same gearing engineers have in my opinion taken a prudent step to protect the engine.

They have decided not to let the engine rev out to the same extent as the previous versions for one reason only, reliability. Retaining that on a mass produced engine is vital. The rev limiter (the HPE does not have a speed limiter) is reached very quickly on the HPE and that is a signal that is important to take note of. Manufacturers don't do that without reason. Some of that reasoning is no doubt due to the small wheels but the engine will be the most important factor here.

With the Kubler ring fitted, the engine still has it's rev limiter but it will be coming in to play much later when the engine is well beyond it's designed and intended revs. Now on the older euro3/4 bikes this is clearly not an issue as the motors are very robust in that format. The HPE, maybe not so much.

The Malossified euro3/4 bikes are fun, but eventually will have a shorter overall life if ridden with gusto. They put out much much more power and at much higher rpm. Something the engines were never intended to do. It will shorten the engines life, but by how much we are not sure just yet.

Piaggio don't take risks. They cannot afford to do so. They won't go for big power and big speed figures on an engine such as the GTS bikes have. It's not suitable. But the HPE is only 1mph slower than the earlier bikes. It's just the earlier bikes can rev out more with that rev limiter set very high by comparison to the HPE. Remember though, the HPE is a totally revised engine and is not designed to rev out as much as the earlier bikes.

Not trying to pour cold water on the Kubler ring, but just making sure everyone understands how this thing works. It's ok to fit one in my opinion but care is needed. Understand what the consequences are for warranty and maybe engine life into the future.