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Old July 6th, 2017, 04:52 PM   #41
DannoXYZ
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Originally Posted by tgold View Post
There is nothing inherent in the 140 profile that makes it a better match than a 150 for the 110 front . That is a matter of using the correct rim width and as I mentioned before, I put the 300 ninja 4" wide rim on the rear so that I wouldn't have a pinched profile. That is the rim width that Dunlop recommends for the A13 150.
When I switch back to the Pirellis I will use the 140 rear as I did before and go back to the stock 3.5" rim width.
The 140 rear Pirelli never gave me issues with grip, so there is no advantage to using the 150. In fact there is a disadvantage because the 150 tire weighs more which adversely affects acceleration.
If you're already on the edge of 110mm front, wouldn't another 5-degrees lean put it off the edge?

Wouldn't putting 150 on 3.5" rim not perform as well as 140 on same 3.5" rim?

I suppose there's a reason Dunlop recommends 4.0" rim for 150 tyre?
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Old July 6th, 2017, 05:55 PM   #42
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#$*!@# it!!! Damn greedy monopolistic filthy capitalist pigs!!!!

I think large part of "issues" people report with front-end is that 110/150 tyre combo has mismatched profiles. You're at edge of front-tyre while rounded rear has more room to lean. A 140/70 rear would be better match for 110/70 front. I've found lowering front-pressure and having just 1-2 psi difference F/R really improves balance. Still would be best to get 140/70 rear.

Horrible bastards! I'm switching to Pirelli !!!
the dunlop race tire vendor at the afm races, sells the a13 in 110/70-150/60 as a set. 250 a set
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Old July 6th, 2017, 08:13 PM   #43
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The biggest thing to me is that the A 13 front will slide earlier than the Pirelli. I was working on my line on a fairly tricky low speed corner and I hit some bumps at the apex which produced a chatter-slide-chatter. Biggest front end slide I’ve had in a while.
I'd agree that overall Supercorsas are better than the Dunlop A13's. I'd also agree that when you get to the point where you are shooting for the top step on the podium, it's probably time to move to the Pirellis. But at that point you're probably blowing big bucks on supersport engine builds, refreshes, 2 cans of MR12 every weekend and a fresh set of tires for every race. Everyone has got to realize their place and spend accordingly. I think the majority of the grid could run A13's just fine.

Something to note that I have found - The amount of chatter from the front of the Dunlops can be reduced when you realize that suspension settings that work for Supercorsas will not work as well for Dunlops. You have to make changes because the carcases are so different. I fought that with Dunlops years ago. Back then is was the Unbeaten 02s, but the A13's have a similar carcass.

One more comment for this thread: There is discussion about tire widths. EVERYONE has to say whether they have a 300 with a 4" rim or a 250 with a 3.5" rim. (or a 250 retrofitted with a 4" rim too) To add to the confusion, people have reported that a certain width doesn't work well but not saying the rim width. IMHO: 300's need a 150 and 250's need the 140.

300's with a 140 on them can run out of edge. (very quickly if your body position sucks) 250's with a 150 pinched on the rim will run out of friction coefficient before the edge can touch down and enlarge the contact patch. Both of these situations limit the maximum lean angle.
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Old July 6th, 2017, 10:45 PM   #44
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the dunlop race tire vendor at the afm races, sells the a13 in 110/70-150/60 as a set. 250 a set
Thanks, I talked to Jose at Thunderhill last weekend about a set for AFM-round4. He can't get the 140/70 tyre unfortunately. Maybe I'll move up to 250 Superbike next year and get the 300 rear-rim. Along with high-comp pistons... and cams... and Ohlins forks...
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Old July 7th, 2017, 12:05 AM   #45
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Originally Posted by JacRyann View Post
If you're already on the edge of 110mm front, wouldn't another 5-degrees lean put it off the edge?

Wouldn't putting 150 on 3.5" rim not perform as well as 140 on same 3.5" rim?

I suppose there's a reason Dunlop recommends 4.0" rim for 150 tyre?
No, a 150 compresses the edges raising the tire profile, you will never reach the edge of the tire as it starts to round away from the surface when leaned over, like a muffin.
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Old July 7th, 2017, 06:23 AM   #46
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Originally Posted by JacRyann View Post
Thanks, I talked to Jose at Thunderhill last weekend about a set for AFM-round4. He can't get the 140/70 tyre unfortunately. Maybe I'll move up to 250 Superbike next year and get the 300 rear-rim. Along with high-comp pistons... and cams... and Ohlins forks...
Jack, i forget your on a 250
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Old July 16th, 2017, 02:10 PM   #47
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First day out on the Michelin RS 150 rear for my 300. It felt just as good as the Alphas, but there again new tires always feel great! I'll keep you updated as it wears, right now it's only got about 110 miles on it. Even though it was pretty damn hot out there today, it did not slide or squirm much at all. I'll have to try and push it a little harder next time.
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Old July 16th, 2017, 03:32 PM   #48
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I'm running Bridgestone RS10s, 110 and 140 on my 250 and have noticed that I need to run pretty low pressures, 24 front and 25 rear cold. This was on a 100º day and they weren't overheating. I've heard of others running these same pressures coming off warmers.
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Old July 16th, 2017, 04:55 PM   #49
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I'm running Bridgestone RS10s, 110 and 140 on my 250 and have noticed that I need to run pretty low pressures, 24 front and 25 rear cold. This was on a 100º day and they weren't overheating. I've heard of others running these same pressures coming off warmers.
races today were 100 deg 23front 25 rear, hot off the warmers.
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Old July 17th, 2017, 10:21 AM   #50
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So apparently Photobucket is now requiring you to pay direct linking. What other alternatives are people using, because I sure as hell am not going to pay $400 for hosting
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Old July 17th, 2017, 11:09 AM   #51
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so apparently photobucket is now requiring you to pay direct linking. What other alternatives are people using, because i sure as hell am not going to pay $400 for hosting
direct upload from the computer or phone still works
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Old July 17th, 2017, 12:56 PM   #52
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So apparently Photobucket is now requiring you to pay direct linking. What other alternatives are people using, because I sure as hell am not going to pay $400 for hosting
Yup. Any linked images are gone now unless you pay the ransom.

I don't negotiate with Opportunists, so many of my posts and threads are dead now.

I went to Imgur, but haven't figured out how to transfer images from Photo****it to Imgur. I've tried, but was not successful. If anyone knows, please chime in.
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Old July 17th, 2017, 01:14 PM   #53
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You can download entire folders from Photobucket as ZIP file. Save to local drive and expand. Then batch upload entire folder to Imgur.
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Old August 4th, 2017, 05:24 PM   #54
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Here in NZ in our 300 class, we were limited in tyre option we could use, due to our rule book provisions (the 250's were open DOT).
DR11/3's
RS10's
Alpha 13's
BT003RS Street
Conti Attack and SM
M7RR's

Were the bulk of the homologated list. No SC's no Alpha 13 SP's, No slicks, no wets, no warmers, No 120 fronts. 140/150 rears only.

The tyre combo that ended up being the most favoured ws RS10 front and DR11 rear.

A few guys were using DR111 fronts and DR11 rears or DR11 fronts, but the Dr11 front was not seen as a great choice. hard and not a lot of feedback, prone to slide and chatter, but noted as "controllable".

As usual, I took an alternative route an ran Alpha 13's. I was the only one....well almost - bit no one at a national level ran them. I was quite surprised as I would have thought they would have been the tyre of choice out of the list (given no SC's etc), especially against the DR11's.

I ran the last race meeting and 2 ride days on RS10 front and rear. Set a new PB at the local club circuit on these. the RS10 front was seen as the best option available in terms of grip/feel/warm up of the options. I found it didn't seem to warm up as fast as the SC's on guys I was racing with on 250's who could use them, but gave plenty of warning, where as the Alpha 13 didn't - makes me wonder how close I was to the edge on coldish tyres on the Alpha's!

The RS10 rear 140/70 seemed to work okay for me. A couple of guys have used them - but most people are just following the crowd and listening to other's feedback without doing any testing themselves. The comment belief was the RS10 rear had a narrow window for pressure and a couple of riders thought it was flattish profile, therefore they would ride off the edge. I didn't....and playing with tyre pressures based upon circuit and conditions is a given. I got it working okay at my pace pretty quickly (3 sessions), and one of the top guys was using a 150/60 rear, though he did low jump off on the last corner of a race....not sure what the background was, I should ask).

Our rules have opened up a a little - still no wets, but we can have warmers and we can have an DOT tyre, but still basically 110 and 140/150. We have not previously really had the 140/701 SC2's here available (no market).

I suspect that we will see most people jump to thee SC1 front (retail is $100 NZD more than an RS10 front) and probably the DR11 140/70 rear, unless 140/70 SC2's are brought in by the distributor (we cannot use the SC2 unless they are generally available, so no mail order versions allowed from offshore...).

I have a tyre "durometer" which measures rubber hardness.....that was interesting walking around the pits and noting tyre rubber hardness. Though obviously this is only part of the overall dynamic as construction and pressure will have a big bearing). The DR11 front was way hard The lower the number, the softer the rubber:
Alphas 56 front rear
DR11 65 front , 53 rear
Conti Attack Front 64
RS10 front 55
D212 GP pro 3 120/70 front (on my TZ750 and OW01) 60
D211 GP Racer rear 160/60 rear (on my TZ750 and 180/55 rear on my OW01) 60
Avon AM22 soft compound 18 inch race tyre (off my TZ350F) 55, AM23 Rear medium 65. (these are the gold standard 18 inch Bias ply race tyres for TZ's)

The SC's will by guestimate be about 50.

Conti soft front slick was 45.

So given the above, I was really surprised that no one used the Alpha's and favoured the DR11's etc. Can only think it was a feel / feedback thing, or some one had a bad experience and said "don't use" - in fact I had a message sent to me on facebook to that effect....that they were "terrible" ! I think set up had something to do with that and in fact the actual rider (not the person who told me, confirmed that later!).

The big question I have and Vulgr from Aussie may be able to help - is how do the new Alpha 13SP compare to the SC's - Dunlop specifically as best I can tell did the update to compete with the Pirelli. In Aussie they have had them (we have not yet here in NZ) and there have been sporadic sightings of top guys with them, but still the SC's look to be dominant. Dunlop tout them as a full on DOT race tyre and are used the the Asia cup and also the RC390 cup there in the US. The Vid I saw seemed to indicate softer carcass too.

We are possibly getting the SP's here - but not sure. I need to talk to my mate at the Dunlop Importer to find out - I have out of preference run Dunlops but am being swayed by the Pirelli. My ultimate preference would be to use the Dunlop knowing they similar performance to the Pirelli in terms of grip and feel, but just to be "different" and make everyone else wonder - as I can see the Pirelli being ubiquitous.....

I did that for years on my TZ350 - Ran 18 inch KR Dunlops,when every one else ran Avons....until Dunlop stuffed the front tyre and then stopped production! (I gave in and bought Avons at that point!)

So the big question I am getting to after all this typing - is how good are the Alpha 13SP vs the Pirelli SC? Anyone know?

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Old August 4th, 2017, 06:49 PM   #55
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I have a tyre "durometer" which measures rubber hardness.....
I have a shore A durometer also. Let me tell you something, it's only good for one thing and it's not judging a tire for stickiness. Tires change state at operating temperature and their hardness is only one component of what makes them stick. It's more about their composition. Also some race tires measure hard when cool, then soften up a lot when at temp.

The durometer is good for checking tires for their age or heat cycles. Know what a new tire measures then check during it's lifespan for an increasing number. Note that mounted/inflated often measures differently than unmounted, so be sure to standardize.

Hmmm, never heard of the Alpha 13SP, what is that?
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Old August 4th, 2017, 09:58 PM   #56
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Quote:
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I have a shore A durometer also. Let me tell you something, it's only good for one thing and it's not judging a tire for stickiness. Tires change state at operating temperature and their hardness is only one component of what makes them stick. It's more about their composition. Also some race tires measure hard when cool, then soften up a lot when at temp.

The durometer is good for checking tires for their age or heat cycles. Know what a new tire measures then check during it's lifespan for an increasing number. Note that mounted/inflated often measures differently than unmounted, so be sure to standardize.

Hmmm, never heard of the Alpha 13SP, what is that?
In 32 years of racing, I've yet to see a tyre which is hard relative to another tyre, become softer and essentially grippier than a tyre that is already soft....but hey it could happen.

BUT; We're using it (the durometer) for base lining tyres mostly and interestingly, what we are seeing is consistent with where the tyres are falling on the relativity scale in terms of grip etc. It's not something I'd hanging my hat on....but we are seeing consistent results relative to grip, at this level. In this case as you have probably found, its trying to (badly!) get some objective testing into a very subjective world...

DR11 front at 65 measurement, RS10 and Alpha 13 at 53-55 and DR11 rear at 53....let's face it the Dr11 is a competent tyre, but not at a level of of the Alpha 13's etc for grip.

As I said also, there's a lot of variables which can create different grip levels. Case in point. Years ago Bridgestone said the difference between a BT50 and BT50SS was NOT compound and in fact they made the tyres with the same compound, the difference was construction.

Good point about fitted etc!

The durometer has been great for a bit of piss taking in the pits....chat to the guys, show them the durometer, measure their tyre, give a slight shake of the head and suck a bit of breathe....irrespective of whatever it shows!



Alpha 13sp:
1) is the control tyre for MA RC Cup in 2017
2) An updated Alpha 13

There's now an Alpha 14 out too just recently as well.
http://ridersnavi.com/encyclopedia/index.html
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Old August 5th, 2017, 05:51 AM   #57
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Having worked in the urethane casting industry I can tell you that durometer readings are not directly related to grip. Case I point: Many race tires are harder at cooler ambient temperatures than street tires, yet they get considerably gripper when brought up to temperature. Yes, they get softer, but that is when they are heated by warmers or use. So checking durometer readings of various tires at ambient temps is of no value. By the way, you do know that the A13 is a multi compound tire right? So where you take your durometer readings would make a difference in the result.

As for the A13 SPs I am using them on my endurance bike. They work ok, but they aren't as good as the Pirelli Supercorsas. We are winning on the A13s but if the competition got tougher I'd go to the Pirellis in a heartbeat. They are a more confidence inspiring tire for me. And absolutely no need to run the 150 width on a 250. 140 works great.
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Old August 5th, 2017, 01:47 PM   #58
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Where are you getting 140 Alpha-13? I want some!

How does the 13-SP feel compared to the 13 regular? It's certainly has much more flexible casing.
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Old August 5th, 2017, 04:27 PM   #59
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Quote:
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Having worked in the urethane casting industry I can tell you that durometer readings are not directly related to grip. Case I point: Many race tires are harder at cooler ambient temperatures than street tires, yet they get considerably gripper when brought up to temperature. Yes, they get softer, but that is when they are heated by warmers or use. So checking durometer readings of various tires at ambient temps is of no value. By the way, you do know that the A13 is a multi compound tire right? So where you take your durometer readings would make a difference in the result.

As for the A13 SPs I am using them on my endurance bike. They work ok, but they aren't as good as the Pirelli Supercorsas. We are winning on the A13s but if the competition got tougher I'd go to the Pirellis in a heartbeat. They are a more confidence inspiring tire for me. And absolutely no need to run the 150 width on a 250. 140 works great.
Thanks for the feedback on the 13SP's. One of the things that I know about my riding is that when I have confidence in the front end, I go okay. No confidence, no speed....

Was it a better feel of what is happening that gave the confidence? As well as I found the 13's (non sp) to grip, the feedback just wasn't there the same as the RS10 front had.

Interestingy, Avalon Biddle (kiwi lady who is running in 300 SuperSport world championship on a Ninja). Before she headed off to Europe she rode a few laps on my 300 to get a few miles on one (never ridden a Ex300 before, but lots of little bike racing experience). While she weighs probably 50kg vs my 85+ and my bike is sprung for me, her immediate comments were:
1) what a great motor
2) more tellingly, "the feeling from the front end is like the tyre is cold"

Yours and Zaph's comments about durometers noted. The more data you have I think the more you can understand and we are still early on in the game. Will keep logging but also note hot measurements - especially also on the bigger bikes in the stable (The TZ750 and OW on their Dunlop GP's) as to how they shape up when warm.
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Old August 5th, 2017, 07:35 PM   #60
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Where are you getting 140 Alpha-13? I want some!

How does the 13-SP feel compared to the 13 regular? It's certainly has much more flexible casing.
Sorry, I am using the A13 in the 150 width. I meant that there is no need for the 150 Pirelli on the 250 Ninja.
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Old August 5th, 2017, 10:11 PM   #61
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Originally Posted by Twinshock750 View Post
As I said also, there's a lot of variables which can create different grip levels. Case in point. Years ago Bridgestone said the difference between a BT50 and BT50SS was NOT compound and in fact they made the tyres with the same compound, the difference was construction.

Good point about fitted etc!

The durometer has been great for a bit of piss taking in the pits....chat to the guys, show them the durometer, measure their tyre, give a slight shake of the head and suck a bit of breathe....irrespective of whatever it shows!
Quote:
Originally Posted by tgold View Post
Having worked in the urethane casting industry I can tell you that durometer readings are not directly related to grip. Case I point: Many race tires are harder at cooler ambient temperatures than street tires, yet they get considerably gripper when brought up to temperature. Yes, they get softer, but that is when they are heated by warmers or use. So checking durometer readings of various tires at ambient temps is of no value. By the way, you do know that the A13 is a multi compound tire right? So where you take your durometer readings would make a difference in the result.
Yeah, there's more than just rubber compound. Casing construction makes HUGE difference, but neither Pirelli nor Dunlop is giving us much information about their construction. About all we know is there's nylon threads involved, and some steel belting, but nothing specific that we can correlate with performance behavior.

I just happen to have three of tyre models we're talking about: Pirelli Supercorsa, Dunlop Alpha 13, and Alpha 13-SP.


Did a quick test of casing stiffness at room temperature.

Link to original page on YouTube.

Pirellis are closer to race-tyres, they require warmers and take a long time to soften up. At which point, casing's and rubber's more flexible than Alpha 13?

Alpha 13s are more DOT-R tyres that warm up quickly, but doesn't change flexibility or rubber grip as dramatically as the Pirellis.

Alpha 13 SPs, I guess... are an attempt to bridge that divide? It has softer rubber than Alpha 13 regular. The casing is much softer at room-temp and probably won't get that much softer when warmed up. It was designed to not need warmers, thus the "pre-warmed" flexible casing at room-temp. But is it as flexible as the Pirellis @ operating temp?

Anyone have lap-time comparisons of these tyres? With same bike & riders?

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Old August 6th, 2017, 04:19 AM   #62
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I'm still intrigued by those A13 SP's. Where do you buy them?

Are they still dual compound?

Are they still the type of race tire that will get damaged if you freeze them?

Does Dunlop list anywhere a comparison on the base A13 to the SP?

I think a softer carcass is a good thing, especially on a bike like this with a high unsprung weight.
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Old August 6th, 2017, 08:47 AM   #63
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Dunlop Alpha SP
https://www.youtube.com/watch?v=wcpNwAoHwsY

Comparison of Pirelli SC and the A13 and A13SP
https://www.youtube.com/watch?v=J3rZEr8FKwg
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Old August 6th, 2017, 10:38 AM   #64
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I'm still intrigued by those A13 SP's. Where do you buy them?

Are they still dual compound?

Are they still the type of race tire that will get damaged if you freeze them?

Does Dunlop list anywhere a comparison on the base A13 to the SP?

I think a softer carcass is a good thing, especially on a bike like this with a high unsprung weight.
From what I've heard, you have to know somebody in the Cup series. There is a guy at our track that just got some, I'll ask him and let you know
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Old August 10th, 2017, 07:04 AM   #65
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From what I've heard, you have to know somebody in the Cup series. There is a guy at our track that just got some, I'll ask him and let you know
seems odd since its on website in Japan for purchase. maybe they aren't importing them?
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Old August 10th, 2017, 07:24 AM   #66
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It's a monopoly with single importer selling them. No way to get them from anyone else and they only bring in one set of sizes. I'm checking with family in Europe to send me some in 250 sizes. Will cost more in shipping than tyres themselves.
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Old August 10th, 2017, 08:13 AM   #67
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It's a monopoly with single importer selling them. No way to get them from anyone else and they only bring in one set of sizes. I'm checking with family in Europe to send me some in 250 sizes. Will cost more in shipping than tyres themselves.
has anyone checked with Race Tire Service?
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Old August 10th, 2017, 08:45 AM   #68
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has anyone checked with Race Tire Service?
Yep, that's the monopoly, no one else is allowed to sell Alpha-13 tyres. They will only sell you regular Alpha-13 in 110/70-17 & 150/60-17 combo. None of other available sizes. No A-13 SP, zip, nada. That's it.
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Old August 10th, 2017, 08:46 AM   #69
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Yep, that's the monopoly. They will only sell you regular Alpha-13 in 110/70-17 & 150/60-17 combo. None of other available sizes. No A-13 SP, zip, nada. That's it.
yeah I notice there is a 140 rear. I would rather do that on my 250.
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Old August 11th, 2017, 08:52 AM   #70
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Originally Posted by JacRyann View Post
It's a monopoly with single importer selling them. No way to get them from anyone else and they only bring in one set of sizes. I'm checking with family in Europe to send me some in 250 sizes. Will cost more in shipping than tyres themselves.
Why go through all that hassle and expense for a tire that frankly isn't as good as the Pirelli Supercorsa that you can get in a 140 width?
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Old August 11th, 2017, 10:02 AM   #71
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Why go through all that hassle and expense for a tire that frankly isn't as good as the Pirelli Supercorsa that you can get in a 140 width?
What's the time difference on each track between Pirelli SC and Dunlops? From looking at laptimes of recent RC Cup @ Laguna Seca, Alpha-13 SP is just as fast as Pirelli SC.

Problem for me is Pirellis take more skill at their limits and to reach those limits. They grip great, to a high-limit, but break-away is more sudden than with the Apha-13, which tends to be "slipperier" at limit. Alpha-13 start sliding more gradually rather than all-of-a-sudden. So even though they may not reach as high of limit for me, penalty for going over that limit is less severe than with Pirellis.
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Old August 11th, 2017, 03:33 PM   #72
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Yep, that's the monopoly, no one else is allowed to sell Alpha-13 tyres. They will only sell you regular Alpha-13 in 110/70-17 & 150/60-17 combo. None of other available sizes. No A-13 SP, zip, nada. That's it.
Yeah this is pissing me off. The SP is available in other countries, so why the heck can't we get them here. Also, while I like the prices on the Alphas the shipping costs are ridiculous. I'm hoping these Michelin RS tires work out, so I can skip Race Tire Service.
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Old August 11th, 2017, 08:49 PM   #73
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well I am all loaded up for tomorrow, takeoff A13's mounted that I got from Bruce. going to be about 100 deg here in TX, going to try 32/32 off warmers. Me being heavier I prob need to run at the recommended PSI. Ill report back! thanks!
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Old August 12th, 2017, 01:10 PM   #74
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well I am all loaded up for tomorrow, takeoff A13's mounted that I got from Bruce. going to be about 100 deg here in TX, going to try 32/32 off warmers. Me being heavier I prob need to run at the recommended PSI. Ill report back! thanks!
Bruce is da man!!! So you got Alpha-13 SPs? Looking forward to your report, have fun!!!!
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Old August 12th, 2017, 01:53 PM   #75
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Problem for me is Pirellis take more skill at their limits and to reach those limits. They grip great, to a high-limit, but break-away is more sudden than with the Apha-13, which tends to be "slipperier" at limit. Alpha-13 start sliding more gradually rather than all-of-a-sudden. So even though they may not reach as high of limit for me, penalty for going over that limit is less severe than with Pirellis.
That mirrors my experience also. The A13 front does start to slide earlier, but I've done it about 10 times and have managed to recover it without sliding.

That said I'm not sure which tire I would prefer overall. Supercorsa SC do stick to a great lean angle.
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Old August 12th, 2017, 02:45 PM   #76
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Bruce is da man!!! So you got Alpha-13 SPs? Looking forward to your report, have fun!!!!
no I got the non-SP

I lowsided in a chicane 2nd session in. I don't have any reason to think it was the tire. I made a late tip in on the 2nd turn, and just lost the front. I could have grabbed the brake, I dont really know.
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Old August 13th, 2017, 08:13 AM   #77
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looks like I borked up the entry and then when I tipped over for the left hander I ran over a diagonal seam/sealer that some of the local racers says will cause you to lose the front. Lesson learned. I will be able to fix the bike for about $50.

https://www.youtube.com/watch?v=L23ShGoezq0

my previous line through there was better

https://www.youtube.com/watch?v=WzSZkMLqfww
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Old August 13th, 2017, 08:45 AM   #78
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looks pretty bumpy over the seam also. i would probably adj my line.
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Old August 14th, 2017, 07:57 AM   #79
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Originally Posted by daverdfw View Post
looks like I borked up the entry and then when I tipped over for the left hander I ran over a diagonal seam/sealer that some of the local racers says will cause you to lose the front. Lesson learned. I will be able to fix the bike for about $50.

https://www.youtube.com/watch?v=L23ShGoezq0

my previous line through there was better

https://www.youtube.com/watch?v=WzSZkMLqfww
Not playing with words, but IMO it's important to recognize that the seam/sealer was not what caused you to crash. It was how you rode over it that caused you to crash. As racers I think that it is very important to be as objective as possible when assessing events that happen along with our role in them.

Also speaking of sealer and Pirelli vs. Dunlop. I did little brake-check test rides along the sealer covered drive behind my townhouse last year on the Pirellis and noticed nothing unusual. Did the same thing this year (actually more gently) on the Dunlop A 13 SP and the front immediately started to slide at not much more than a walking pace. Now some of that is because of the harder center section on the A-13, but the point: There is still a compromise that may cost you when you make a choice such as feel at the expense of grip.

Another note: Dropping the hot pressure about 1 psi (to 32) seemed to help reduce the chatter I was running into at the previous race weekend.
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Old August 14th, 2017, 08:22 AM   #80
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Not playing with words, but IMO it's important to recognize that the seam/sealer was not what caused you to crash. It was how you rode over it that caused you to crash. As racers I think that it is very important to be as objective as possible when assessing events that happen along with our role in them.

Also speaking of sealer and Pirelli vs. Dunlop. I did little brake-check test rides along the sealer covered drive behind my townhouse last year on the Pirellis and noticed nothing unusual. Did the same thing this year (actually more gently) on the Dunlop A 13 SP and the front immediately started to slide at not much more than a walking pace. Now some of that is because of the harder center section on the A-13, but the point: There is still a compromise that may cost you when you make a choice such as feel at the expense of grip.

Another note: Dropping the hot pressure about 1 psi (to 32) seemed to help reduce the chatter I was running into at the previous race weekend.

oh for sure, its because I didn't cross over it and ran into it. It was a poor line choice on my end. I think I am probably to the pace and point of my riding where Pirelli's might have saved me there. IN the end it was rider error. I was running 32/30 hot off warmers. I had 0 warning, I hit that spot and immediately lost the front.
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