Upgrading the ‘23 V4R front end

[Spooky]

I expect the braking system on the V4R is more than adequate but I would like to get some thoughts on this.

It comes with a 16mm master cylinder and M4.30 calipers. My understanding is that Brembo recommend a 17mm master cylinder.

I am not sure why Ducati chose a 16mm master but I guess they would have their reasons.

I thought it might be beneficial to move to a 17mm master cylinder and was going to get the 17RCS Corsa Corta but the RR is supposed to be available very soon and I’m tempted to go with that. Thoughts on this?

This change requires buttons and I’m looking at Jetprime. This made me consider the Jetprime QA, although the throttle on the bike is far better than the previous version and has no slop and appears to have 60 degrees throw, which would be the same as the Jetprime. Is it worth changing the throttle or should I just get the buttons that replace the throttle cover and stick with the original throttle.

I thought while doing this that I might as well get some longer bars and started looking at clip-ons (disappearing down the rabbit hole). Spider seem popular but I also thought the IMA ones looked interesting or perhaps Extreme Components as they also have the steering damper mount built in. Thoughts?

Lastly, the calipers. GP4-MS are highly regarded but would there be a noticeable difference between these and the M4.30 that are on the bike? Thoughts on how the calipers compare?

I’m not expecting this to instantly take time off laps - that’s down to me and I don’t expect upgrading parts to make any difference, although perhaps it will change the feel, maybe give confidence, etc. The bike is used almost exclusively on track.

So, I’d appreciate your thoughts on all of this.

As an aside, on some forums these types of questions are usually met with a response along the lines of “you’re better off spending the money on track time, tyres, tuition”, etc. Spending money on upgrades doesn’t prevent this.

 

[BMW Alpina]

Hello Spooky,

I always thought the Panigale V4R came with the Stylema R caliper from factory, however after reading your post and check at Ducati website, it looks like they use the standard Stylema (NON-R) front caliper.

The GP4-MS is still primarily design for road use.
The first version of GP4-MS is just the Stylema with the same piston diameter but machined from block of aluminum while the Stylema was CAST (not machined). In theory the differences will be rigidity, that the GP4-MS should have more, and maybe lighter because they can be machined strategically to further optimized weight reduction.
Since the stock Stylema already quite a good design, I really doubt the first version of GP4-MS will make much difference.

However, there is a newer version of GP4-MS with cooling fins, and this should help improve brake cooling at track speed. So if you buy a GP4-MS, try to buy the second version with improved cooling.

Having said that both version of GP4-MS still came with aluminum piston, which is a good heat conductor (and you want less heat conducting properties for your brake piston, to reduce the heat transfer from brake pads to brake fluid).
You can upgrade the GP4-MS with either Braketech stainless steel piston (lower cost but heavier weight) or the after market Titanium Piston (lower weight, but more expensive).
Most of the Brembo more track oriented brake caliper use Titanium piston for less heat transfer and lighter weight reason.

Brembo has different caliper design more for track use such as the GP4-RR (I am trying to sell mine) or the GP4-LM (I want to buy this after I can sell my GP4-RR) or the GP4-PR. There are other older models that I am not remember on top of my head now.
They all came with Titanium piston from factory. The problem is, some of them only with 108mm spacing and different offset, meaning you need to replace your lower fork bracket. But even if they came in 100mm spacing like the GP4-RR, they still require different brake rotor offset.
Beside a full brake rotor upgrade to the Pistabassa low band but thicker rotors also required (for safety so the brake pads would not slide out when they worn out)

If it is my money, I think the easiest and best upgrade will be using Brembo track design caliper. You just need to purchase Motocorse Lower Fork bracket for 108mm spacing, then use the GP4-LM with 108mm spacing and use Pistabassa rotor for Panigale V4.
If there is a need to adjust the offset, then it's just adding thin aluminum spacer to adjust the Pistabassa rotor offset. But my feeling is you don't even have to add spacer since Motocorse design their caliper bracket for stock offset. (I could be wrong, since I applied this on my 998 instead of my Panigale). You can look on the step by step instruction I provided when I was upgrading my Panigale V4S Ohlins forks with Motocorse fork bottom for my 998 build.

Regarding the 16mm vs 17mm, you will feel very slightly less lever travel and firmer with the 17mm if you are using GP4-MS. But if you are using larger piston caliper such as GP4-LM or GP4-RR, then you need the 19mm version.
But 16mm should still work with GP4-MS.

I think the throttle change from stock to Jetprime or Domino will be great either way, but I don't think the stock Ducati throttle (eventhough it is improve with no slack) will still have Quick Action or Faster response such as the Domino... If someone know differently since this is the new V4R, please correct me.

The ImA also have steering damper mounting on their clip-on (for stock steering damper). I myself use the longer clip-on bar from Melotti Racing which don't have provision for stock steering damper, thus I need to customize.
However Melotti Racing did make a side mounted steering damper bracket (originally develop for Barni Racing Team), in case you don't mind changing your stock steering damper to side mounted.

Last regarding your statement: As an aside, on some forums these types of questions are usually met with a response along the lines of “you’re better off spending the money on track time, tyres, tuition”, etc. Spending money on upgrades doesn’t prevent this.
I couldn't agree more with you. A lot of poster on other forums like to say this mainly because they feel jealous that they cannot afford the cost or they don't know how to perform the upgrade. Or sometimes, they just like to argue with other forum members (to compensate for something in their real life).
This is why I started this forum a few years ago. It's for people who want to share experience modifying their bike without the worry of "the typical discouraging negative comments".

It is true, that you can improve the rider by spending money on track time, but if you can also improve the bike in parallel, why not? So totally agree with you.

 

[Spooky]

Thanks for the detailed reply.

Regarding clip-ons, I like a lot about the Melotti clip-ons and with the top triple it would be a nice setup and easy to set the angle correctly due to the markings, but they are sold up to 52mm and I believe the forks on the 2023 V4R are 53mm. That’s confused me a bit. Also, how is the angle of the bars changed?

If using this setup then I could use a steering damper support such as the ones from Extreme Components, Spider or Bonamici (there are probably others). As long as there is enough of the widest part of the upper fork left to attach it then it should work. I think the Melotti clamps are 45mm tall.

Extreme Components do clip-ons with the steering damper support built in and I’m thinking they might be a good solution. I haven’t seen a huge amount about them but what I have seen seems to say they make quality stuff.

I don’t think there would be a problem using the Extreme Components with the OEM top triple - I realise it would be a few mm lower because of the locating tab but I can’t see that this would really matter. This seems like the simplest and cleanest solution.

Overall, I like the Melotti stuff but I am a bit concerned that it’s for 52mm forks and mine are apparently 53mm (this is the size that the ones from Extreme Components are).

Regarding the throttle, as far as I can tell the OEM throttle seems to have about 60 degrees throw, which is the same as the Jetprime. I’d guess quality of the Jetprime would be better and there’s the metal housing as well. I think I’m likely to go for this even though I think any benefit may well be marginal to non-existent…

I was interested by your comments about the calipers. I thought Stylema were above M4? The specs say ‘M4.30’ for my bike and I didn’t think that was the same caliper as Another bike I have came with Stylema R and MSC master cylinder and I thought it was good (still 16mm though - it’s interesting that Ducati choose 16mm when Brembo recommend 17mm - perhaps safer for someone on the road grabbing a handful of brake).

I am going to stay with 100mm for the time being and so it’s a case of deciding if the GP4-MS is a worthwhile upgrade from the M4.30. It’s certainly a lot more expensive and I don’t think I’d want to spend more than that at this time (the next step up is quite a bit more and would be more involved than I want to get).

The only GP4-MS I have seen with fins is 108mm.

Regarding the master cylinder, 17mm sounds like it might be good as I wouldn’t mind just a bit less lever travel before getting some bite and of course it is what Brembo recommend for a 30mm piston. Timing is interesting because I am told that the RR really, really, definitely should be arriving very soon… I wonder if it’s worth holding on for it or just get the 17RCS Corsa Corta. If the RR was definitely going to be deliverable in April then I’d wait as it looks great but I wouldn’t want to wait until the end of the season. Then again, I guess I could use the OEM 16mm master cylinder and upgrade that later if I wanted. It’s not like the OEM setup is poor and it certainly stops the bike.

 

[bp_SFV4]

I think the throttle change from stock to Jetprime or Domino will be great either way, but I don't think the stock Ducati throttle (eventhough it is improve with no slack) will still have Quick Action or Faster response such as the Domino... If someone know differently since this is the new V4R, please correct me.

I've read quite a few reports that the new V4R throttle has the same throw and feel of the Domino.

 

[BMW Alpina]

Thanks for the detailed reply.

Regarding clip-ons, I like a lot about the Melotti clip-ons and with the top triple it would be a nice setup and easy to set the angle correctly due to the markings, but they are sold up to 52mm and I believe the forks on the 2023 V4R are 53mm. That’s confused me a bit. Also, how is the angle of the bars changed?

If using this setup then I could use a steering damper support such as the ones from Extreme Components, Spider or Bonamici (there are probably others). As long as there is enough of the widest part of the upper fork left to attach it then it should work. I think the Melotti clamps are 45mm tall.

Extreme Components do clip-ons with the steering damper support built in and I’m thinking they might be a good solution. I haven’t seen a huge amount about them but what I have seen seems to say they make quality stuff.

I don’t think there would be a problem using the Extreme Components with the OEM top triple - I realise it would be a few mm lower because of the locating tab but I can’t see that this would really matter. This seems like the simplest and cleanest solution.

Overall, I like the Melotti stuff but I am a bit concerned that it’s for 52mm forks and mine are apparently 53mm (this is the size that the ones from Extreme Components are).

Regarding the throttle, as far as I can tell the OEM throttle seems to have about 60 degrees throw, which is the same as the Jetprime. I’d guess quality of the Jetprime would be better and there’s the metal housing as well. I think I’m likely to go for this even though I think any benefit may well be marginal to non-existent…

I was interested by your comments about the calipers. I thought Stylema were above M4? The specs say ‘M4.30’ for my bike and I didn’t think that was the same caliper as Another bike I have came with Stylema R and MSC master cylinder and I thought it was good (still 16mm though - it’s interesting that Ducati choose 16mm when Brembo recommend 17mm - perhaps safer for someone on the road grabbing a handful of brake).

I am going to stay with 100mm for the time being and so it’s a case of deciding if the GP4-MS is a worthwhile upgrade from the M4.30. It’s certainly a lot more expensive and I don’t think I’d want to spend more than that at this time (the next step up is quite a bit more and would be more involved than I want to get).

The only GP4-MS I have seen with fins is 108mm.

Regarding the master cylinder, 17mm sounds like it might be good as I wouldn’t mind just a bit less lever travel before getting some bite and of course it is what Brembo recommend for a 30mm piston. Timing is interesting because I am told that the RR really, really, definitely should be arriving very soon… I wonder if it’s worth holding on for it or just get the 17RCS Corsa Corta. If the RR was definitely going to be deliverable in April then I’d wait as it looks great but I wouldn’t want to wait until the end of the season. Then again, I guess I could use the OEM 16mm master cylinder and upgrade that later if I wanted. It’s not like the OEM setup is poor and it certainly stops the bike.

Hello Spooky,
You can order the Melotti clip-on handlebars with custom diameters. You can specify 53mm. Just contact them by email. Clara usually answers your email, and from time to time, Diego Melotti will also respond if the discussion becomes very technical. They are all super nice team.
I special ordered a pair of 54.5mm diameter clip-ons for my RVP-25 WSBK forks, and it's a PERFECT fit.
For angle adjustment, do you mean vertically or horizontally? Vertically, it's fixed, but horizontally you can adjust freely and if you purchase Melotti Racing upper triple clamp, they even have some matching laser marking between the triple clamp and handle bar to make it easy for you.
I installed my Melotti racing clip-on on my build to the RVP-25 fork, so you can review the pictures in my build thread for reference. I just have not had a chance to install all the button/throttle/MC yet because I am busy with my 998.
AELLA Japan also make a clip on handle bar with build in mounting provision for stock Ohlins steering damper. Their product also super nice, but more for road use. The Melotti Racing clip-on is significantly longer handle bar than the stock Ducati.

I take the screenshot below from the Ducati website for the V4R tech spec. You can see that the Stylema is the same as M4.30. I believe M4.30 means Monoblock 4 piston, 30mm diameter.


Regarding GP4-MS, Brembo USA (Race Technology) confirmed to me that the GP4-MS 100mm will also come with cooling fins in the future (I asked this question more than 1 year ago).... so hopefully it will be release soon

Last, are you sure the brake MC on V4R is 16mm from what I know (and again, I might not be up to date), the 16mm is for the Clutch MC. Where did you see that it say 16mm for V4R?

 

[BMW Alpina]

I've read quite a few reports that the new V4R throttle has the same throw and feel of the Domino.

Wow, that must be by design and make the R more suitable for track use. Very nice for Ducati to pay attention to this.

 

[Spooky]

Wow, that must be by design and make the R more suitable for track use. Very nice for Ducati to pay attention to this.

It definitely feels like it has a stronger return spring and the throw is shorter. I’ve not used a Domino so I can’t compare. This does give the option of using the OEM throttle with the Jetprime switches that replace the cover on the throttle.

I was very surprised when I collected the V4R and found zero slop in the throttle. It’s a definite improvement and I’m surprised it’s not mentioned more.

 

[Spooky]

Hello Spooky,
You can order the Melotti clip-on handlebars with custom diameters. You can specify 53mm. Just contact them by email. Clara usually answers your email, and from time to time, Diego Melotti will also respond if the discussion becomes very technical. They are all super nice team.
I special ordered a pair of 54.5mm diameter clip-ons for my RVP-25 WSBK forks, and it's a PERFECT fit.
For angle adjustment, do you mean vertically or horizontally? Vertically, it's fixed, but horizontally you can adjust freely and if you purchase Melotti Racing upper triple clamp, they even have some matching laser marking between the triple clamp and handle bar to make it easy for you.
I installed my Melotti racing clip-on on my build to the RVP-25 fork, so you can review the pictures in my build thread for reference. I just have not had a chance to install all the button/throttle/MC yet because I am busy with my 998.
AELLA Japan also make a clip on handle bar with build in mounting provision for stock Ohlins steering damper. Their product also super nice, but more for road use. The Melotti Racing clip-on is significantly longer handle bar than the stock Ducati.

I take the screenshot below from the Ducati website for the V4R tech spec. You can see that the Stylema is the same as M4.30. I believe M4.30 means Monoblock 4 piston, 30mm diameter.
View attachment 13647

Regarding GP4-MS, Brembo USA (Race Technology) confirmed to me that the GP4-MS 100mm will also come with cooling fins in the future (I asked this question more than 1 year ago).... so hopefully it will be release soon

Last, are you sure the brake MC on V4R is 16mm from what I know (and again, I might not be up to date), the 16mm is for the Clutch MC. Where did you see that it say 16mm for V4R?

It’s stated in the owner’s manual as being 16mm for the brake (16/21).

Next to that in the manual it confirms Stylema. I saw M4 advertised and thought it was a different caliper.

Is the GP4-MS with cooling fins the GP4-MotoGP that’s supposed to come out ‘soon’?

Thanks for the information on the Melotti bars. If I go with Melotti then I’ll probably get the upper triple due to the markings for easy alignment. Extreme Components are in the running as well and have vertical adjustment available and the built-in steering damper support.

Regarding calipers, it seems I would not find much difference between my existing Stylema and the GP4-MS? I had read that there was improved feel. Perhaps not enough to justify the price?

I might spend less than I was planning!

 

[Spooky]

I’ve been trying to research this a bit more. It looks like the GP4-MS with fins was announced quite some time ago and that 100mm was supposed to be released as well but still no sign of them being available and they have since announced the GP4-MotoGP, which will be available in 100mm. I wonder if the GP4-MS with fins will actually arrive in 100mm and, if it does, when this might happen.

It’s odd how Brembo announce products and then take a year or two (or more) to release them for sale… It seems daft from a marketing point of view as the buzz from the announcement is lost by the time people can actually buy them.

I expect the GP4-MotoGP is going to cost more than the GP4-MS, if for no other reason than ‘MotoGP’ being in the product name.

The fins look very cool and no doubt have a technical benefit but I expect it would be of zero performance benefit for trackday use. I can easily wait as the Stylema are excellent calipers. I get the feeling that there’s no real performance difference between the Stylema and GP4-MS and it is simply down to a different feel?

 

[BMW Alpina]

I am not sure when the GP4-MS 100mm with cooling fins will ever be released because even the 108mm is still on backorder. However, they are different designs. The GP4-MS is a road caliper first, while the GP4-MotoGP is a track caliper first but can be used on the road.
However, please note that the GP4-MotoGP still uses aluminum pistons, so they should still be in the lower price range of track calipers.
I think you will get more feel improvement with a Corsa Corta or the Billet Master Cylinder from Brembo, since it is directly in contact with your hand.
I think you can only feel the more rigid billet design of the GP4-MS when you squeeze the brake super hard and when the caliper is already super hot. (because aluminum will be less rigid when hot, so any mechanical design that improve rigidity should help).
Feel can also be more readily feel-able with different pad compounds.

However, the GP-MS with cooling fins does look much nicer than the Stylema, though

 

[Spooky]

The one with fins definitely looks more trick.

The GP4-MotoGP will probably be a good amount of money more than the MS and I’m sure it will be a very long time before it’s actually available to buy. Brembo still describe it as being for the road.

I think the decision about buying the GP4-MS might depend on how many glasses of wine I have had when I order parts…

As for the RR master cylinder, I’ve seen online shops with text saying it will be in stock in August… 2023… I have spoken to a couple of suppliers who say they hope to start getting them in April but based on previous expectations they wouldn’t be suprised if it’s not closer to the end of summer. I might just get the 17RCS Corsa Corta, but I’d definitely prefer to get the RR if it was available.

 

[Spooky]

I’ll definitely be going for the non-RR Corsa Corta - I can’t see it being available for quite some time based on what I’m hearing from suppliers, combined with the number of pre-orders they already have for them.

A few people have recommended the 19RCS. Another person is using the expensive GP one but still went for 19x18. I find this rather interesting. Obviously the Brembo recommendation is 17mm. Ducati supply with 16mm. Two of the people recommending 19mm have said that the calipers are extremely capable and that the 19mm really helps to exploit this. One said that the Corsa Corta lets you dial in the feel you want and another seemed to suggest that the MS calipers have a slightly softer initial feel and the 19mm works well with this.

Thoughts?

I’ve decided on the Jetprime throttle and switches. I’m waiting for confirmation regarding Melotti stuff but leaning toward Extreme Components, maybe with a Melotti upper-triple.

 

[bp_SFV4]

I'd be interested to try a 19, but would probably go with a 17 first. I think I wrote it on the other forum, but Ducati going with 16 is likely their test riders preference. They are going for the ability to better modulate the brake at the expense of lever feel. If you bought either and didn't like it I'm quite sure you could recover some of the expense selling it.

I'd only go 19 if ABS was still intact though.

On that note, the ABS system can detect the fluid pressure at the master side of the line and IIRC the caliper side of the line. So a 17 or 19 would not affect the ABS system. I just think since the 19 can offer more braking force, being able to lean on the ABS is beneficial.

If I were to red man this reply, it would be that, in the words on YCRS, you have to load the tire to work the tire. Smaller piston sizes would lead to a more gradual increase of load under heavy braking on the front tire. So maybe 17?

 

[BMW Alpina]

I'd be interested to try a 19, but would probably go with a 17 first. I think I wrote it on the other forum, but Ducati going with 16 is likely their test riders preference. They are going for the ability to better modulate the brake at the expense of lever feel. If you bought either and didn't like it I'm quite sure you could recover some of the expense selling it.

I'd only go 19 if ABS was still intact though.

On that note, the ABS system can detect the fluid pressure at the master side of the line and IIRC the caliper side of the line. So a 17 or 19 would not affect the ABS system. I just think since the 19 can offer more braking force, being able to lean on the ABS is beneficial.

If I were to red man this reply, it would be that, in the words on YCRS, you have to load the tire to work the tire. Smaller piston sizes would lead to a more gradual increase of load under heavy braking on the front tire. So maybe 17?

@bp_SFV4 , The larger your master cylinder diameter is, the harder you need to pull to create the same braking pressure on the caliper, meaning the larger the master cylinder bore diameter, the less braking force (to the caliper piston) it will provide with the finger power being constant.

Let's say you want to exert X pressure by the piston in your caliper to your disk brake.
A 19mm master cylinder requires you to pull the lever harder (with more force) for the piston in your caliper to exert the same X pressure on your disk brake. (But The lever will have less travel compare to 17mm)
A 17mm master cylinder requires you to pull the lever softer (with less force) so that the piston in your caliper can exert the same X pressure on your disk brake. (But The lever will have more travel compare to 19mm)

Again, the 19mm master cylinder lever will travel LESS than the 17mm master cylinder to push the same amount of piston travel in your brake caliper.
This is the analogy of front and rear sprocket. If you have a larger front sprocket, you will have to turn that sprocket less and create more travel for the rear sprocket, but the effort to turn that front sprocket will be harder.

This also mean, if you apply the maximum force your finger muscle can apply, the 17mm master cylinder will actually be able to push the piston on your caliper at HIGHER force than the 19mm master cylinder (as long as the piston inside the 17 mm master cylinder has not bottom-up)
So 17mm master cylinder actually can provide you with more braking power than the 19mm with the same finger power.

Here is a good quick video about this:

and

I’ll definitely be going for the non-RR Corsa Corta - I can’t see it being available for quite some time based on what I’m hearing from suppliers, combined with the number of pre-orders they already have for them.
A few people have recommended the 19RCS. Another person is using the expensive GP one but still went for 19x18. I find this rather interesting. Obviously the Brembo recommendation is 17mm. Ducati supply with 16mm. Two of the people recommending 19mm have said that the calipers are extremely capable and that the 19mm really helps to exploit this. One said that the Corsa Corta lets you dial in the feel you want and another seemed to suggest that the MS calipers have a slightly softer initial feel and the 19mm works well with this.
Thoughts?
I’ve decided on the Jetprime throttle and switches. I’m waiting for confirmation regarding Melotti stuff but leaning toward Extreme Components, maybe with a Melotti upper-triple.

@Spooky, if you plan to buy the GP4-MS, definitely buy the 17 mm RCS.
This way, you will still have some lever travel to "easily modulate." The 19mm RCS will not have enough travel, plus it will be harder to pull, which not only makes it harder for you to modulate (less travel distance to modulate) but also requires your finger to be much stronger to modulate the same amount of power to your piston in the caliper.
Follow what the Brembo official recommends: use the 17RCS for GP4-MS with a 4 x 30mm piston caliper.
I don't know what the "2 people" mean about GP4-MS as a very capable caliper thus recommend the 19mm. Because this is basic hydraulic. If they mean the GP4-MS is a very rigid caliper (thus capable), that actually means you do NOT need a larger diameter MC, because the GP4-MS won't flex under high pressure.
The GP4-MS is just a PASSIVE device. It can only transfer the pressure to disk rotor from the pressure you pull at the master cylinder lever. GP4-MS does not add or subtract hydraulic power. (It is not self-powered).

 

[Spooky]

@bp_SFV4 , The larger your master cylinder diameter is, the harder you need to pull to create the same braking pressure on the caliper, meaning the larger the master cylinder bore diameter, the less braking force (to the caliper piston) it will provide with the finger power being constant.

Let's say you want to exert X pressure by the piston in your caliper to your disk brake.
A 19mm master cylinder requires you to pull the lever harder (with more force) for the piston in your caliper to exert the same X pressure on your disk brake. (But The lever will have less travel compare to 17mm)
A 17mm master cylinder requires you to pull the lever softer (with less force) so that the piston in your caliper can exert the same X pressure on your disk brake. (But The lever will have more travel compare to 19mm)

Again, the 19mm master cylinder lever will travel LESS than the 17mm master cylinder to push the same amount of piston travel in your brake caliper.
This is the analogy of front and rear sprocket. If you have a larger front sprocket, you will have to turn that sprocket less and create more travel for the rear sprocket, but the effort to turn that front sprocket will be harder.

This also mean, if you apply the maximum force your finger muscle can apply, the 17mm master cylinder will actually be able to push the piston on your caliper at HIGHER force than the 19mm master cylinder (as long as the piston inside the 17 mm master cylinder has not bottom-up)
So 17mm master cylinder actually can provide you with more braking power than the 19mm with the same finger power.

Here is a good quick video about this:

and

@Spooky, if you plan to buy the GP4-MS, definitely buy the 17 mm RCS.
This way, you will still have some lever travel to "easily modulate." The 19mm RCS will not have enough travel, plus it will be harder to pull, which not only makes it harder for you to modulate (less travel distance to modulate) but also requires your finger to be much stronger to modulate the same amount of power to your piston in the caliper.
Follow what the Brembo official recommends: use the 17RCS for GP4-MS with a 4 x 30mm piston caliper.
I don't know what the "2 people" mean about GP4-MS as a very capable caliper thus recommend the 19mm. Because this is basic hydraulic. If they mean the GP4-MS is a very rigid caliper (thus capable), that actually means you do NOT need a larger diameter MC, because the GP4-MS won't flex under high pressure.
The GP4-MS is just a PASSIVE device. It can only transfer the pressure to disk rotor from the pressure you pull at the master cylinder lever. GP4-MS does not add or subtract hydraulic power. (It is not self-powered).

I certainly wouldn’t like a lever that’s not easy to modulate. The comment made about braking capability wasn’t about the MS - the comment that was made to me was that the 19 allows you to more fully exploit the braking ability that these bikes have (it’s not like they come with rubbish brakes). I’m not sure why that would be as the pressure exerted on the discs would presumably be the same and all that changes is effort and feel?

The comment made to me about the MS caliper was that it has a softer initial feel - no idea if there’s anything in that or it was just in those particular systems and could be attributed to something else. People often make changes and attribute a difference to component x when it might have been component y, hence I would generally change one thing at a time (but not always).

I find it interesting that the KTM RC8 C has Stylema brake calipers and comes with the 19RCS Corsa Corta. It’s fully aimed at track and has the 19. The V4R is obviously a homologated road bike, has Stylema calipers and comes with the 16. Both use the same calipers yet they use quite different master cylinder sizes (a smaller disc size on the KTM and it weighs a lot less and has a lot less power). Brembo recommend 17 and they both ignore ignore that and make different choices.

 

[Spooky]

@BMW Alpina

I’ve tried emailing Melotti twice and got no response.

You mentioned that they can produce 53m clip-ons but I noticed that the upper triple, which I am more interested in than the clip-ons, does not mention fork size. Is this not important for the upper triple?

Sorry for all the questions but bviously all of this is quite new to me…

 

[BMW Alpina]

I certainly wouldn’t like a lever that’s not easy to modulate. The comment made about braking capability wasn’t about the MS - the comment that was made to me was that the 19 allows you to more fully exploit the braking ability that these bikes have (it’s not like they come with rubbish brakes). I’m not sure why that would be as the pressure exerted on the discs would presumably be the same and all that changes is effort and feel?

The comment made to me about the MS caliper was that it has a softer initial feel - no idea if there’s anything in that or it was just in those particular systems and could be attributed to something else. People often make changes and attribute a difference to component x when it might have been component y, hence I would generally change one thing at a time (but not always).

I find it interesting that the KTM RC8 C has Stylema brake calipers and comes with the 19RCS Corsa Corta. It’s fully aimed at track and has the 19. The V4R is obviously a homologated road bike, has Stylema calipers and comes with the 16. Both use the same calipers yet they use quite different master cylinder sizes (a smaller disc size on the KTM and it weighs a lot less and has a lot less power). Brembo recommend 17 and they both ignore ignore that and make different choices.

I am not sure why KTM RC8 C has 19RCS, but unless somehow they have more hydraulic fluid to move somewhere in the front brake circuit, that means, they will have less clamping power compare if they are using 17RCS. It could be by design, so it won't be as easy to lock up their front tires with the same finger power.
The 16 on the V4R might be designed to make it easier for regular riders to brake harder, and in some way, the longer travel can always be compensated by slightly changing the pivot point and lever attachment to the shaft.

@BMW Alpina

I’ve tried emailing Melotti twice and got no response.

You mentioned that they can produce 53m clip-ons but I noticed that the upper triple, which I am more interested in than the clip-ons, does not mention fork size. Is this not important for the upper triple?

Sorry for all the questions but bviously all of this is quite new to me…

This is the email to Melotti, and sometimes when they are busy with the racing season, it could take a bit longer for them to respond: sales@melottiracing.com
The upper triple will come standard with 53mm, which I what I bought the first time when I still have my stock Ohlins on my V4.
Then I custom order the second triple with 54.5mm for my RVP-25 WSBK Ohlins.
Both have custom laser marking done by Melotti.

Melotti also offer a replica design of their Barni Racing WSBK upper triple. This version can come with any diameter forks you specify. I posted here about this a while ago.
Diego offer me this Barni design, but I still prefer the style of their original street design, so I purchase the street design.

 

[Spooky]

I am not sure why KTM RC8 C has 19RCS, but unless somehow they have more hydraulic fluid to move somewhere in the front brake circuit, that means, they will have less clamping power compare if they are using 17RCS. It could be by design, so it won't be as easy to lock up their front tires with the same finger power.
The 16 on the V4R might be designed to make it easier for regular riders to brake harder, and in some way, the longer travel can always be compensated by slightly changing the pivot point and lever attachment to the shaft.



This is the email to Melotti, and sometimes when they are busy with the racing season, it could take a bit longer for them to respond: sales@melottiracing.com
The upper triple will come standard with 53mm, which I what I bought the first time when I still have my stock Ohlins on my V4.
Then I custom order the second triple with 54.5mm for my RVP-25 WSBK Ohlins.
Both have custom laser marking done by Melotti.

Melotti also offer a replica design of their Barni Racing WSBK upper triple. This version can come with any diameter forks you specify. I posted here about this a while ago.
Diego offer me this Barni design, but I still prefer the style of their original street design, so I purchase the street design.

I don't think the KTM has the ABS stuff to deal with but I'd have thought that would mean less fluid to push and a more direct feel, in addition to less mass to slow down. I was just going to get the 17mm as it's what Brembo recommend but I do find it interesting that a few people have recommended the 19mm and KTM are also using it with the Stylema calipers.

That's good news about the Melotti upper-triple being 53mm. Thanks for confirming.

I saw your post about the Barni upper triple - looks all business... quite interesting but I think they said around the beginning of January 2023 that they would release it in a few months and I've not seen it. It would certainly be a different look than most V4s at the track!

 

[BMW Alpina]

I don't think the KTM has the ABS stuff to deal with but I'd have thought that would mean less fluid to push and a more direct feel, in addition to less mass to slow down. I was just going to get the 17mm as it's what Brembo recommend but I do find it interesting that a few people have recommended the 19mm and KTM are also using it with the Stylema calipers.

That's good news about the Melotti upper-triple being 53mm. Thanks for confirming.

I saw your post about the Barni upper triple - looks all business... quite interesting but I think they said around the beginning of January 2023 that they would release it in a few months and I've not seen it. It would certainly be a different look than most V4s at the track!

Melotti Racing is a small operation, many things they offer might not be listed on the website. The best way is to talk directly to them. They even sourced me the RVP-25 specific front mud guard bracket and speed sensor as used by Barni Racing Team for their WSBK bike, (which they do not listed anywhere) and it works for my application.

 

[Spooky]

Melotti Racing is a small operation, many things they offer might not be listed on the website. The best way is to talk directly to them. They even sourced me the RVP-25 specific front mud guard bracket and speed sensor as used by Barni Racing Team for their WSBK bike, (which they do not listed anywhere) and it works for my application.

Good to know and I did get a response from them shortly after I posted here to say that their technical team would be in touch shortly, sorry for the delay, etc.