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Old 08-10-2007, 11:11 PM   #76
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I love the 26mm tires. Haven't broken one yet. After breaking 8, yes 8, 28mm 2-stage in one race night I'll never go back to the dish rim. Now I don't have to Can't wait till the new rims come out.
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Old 08-14-2007, 12:01 AM   #77
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We discovered something interesting over the last few months. Many local shops have claimed that our double pink and double pink/orange combo was too aggressive. They said "magenta" rears and "cyan" fronts from another brand were much easier for the locals to hook up with. So we went out and bought some of these tires from a number of sources and discovered that the "magenta" was not a 35 like our double pink, but was a 32 instead. The "cyan" was, in fact, our purple/orange. This explains a lot. We are now offering these two compounds in addition to our current line.

Regarding the strength of the wheel....our spoked wheel is much stronger than our dish wheel was. It has more to do with the plastic and rib design than whether it is a dish or a spoke. The new wheel is made from the same material we use on our 1/8 wheel. These will be VERY strong.

I hate to dodge the question about how hard the orange is, but the hardness depends on what they send us at the time. And it can vary A LOT. We have no control over that process, however if it comes in too soft, we use it for a non-R/C application.
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Old 08-14-2007, 05:00 PM   #78
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Just for those wondering.... Jack and I spoke extensively about the main factors and combinations we wanted to create into the Prism line of wheels. Here's a little insight on the whole project:

#1 - Durability was the #1 item Jack wanted. He told me this was the top priority over everything else as he wanted a solid, dependable product for the customer that would not break or fail for any level racer. We've gone over several plastics that we could have used to slightly reduce weight/increase stiffnes and greatly reduce the cost but in the end Jack choose to use an extremely durable (and expensive) plastic to ensure we had the best rim possible.

#2 - A distinct look was the next item on the list. Jack wanted something to set his wheel a part from any other tire on the market. This way there was no question what a driver was using when his/her car hit the track.

From the engineering side, it was my job to make sure the rims were strong, light, true and maximized whatever offset and rim flex I could to increase traction and consistancy:

#3 - The 1/12 rear rim went from a 0mm back face offset to the Prism's 3mm offset. This allows the hubs to mount closer to the center line of the wheel which helps the wheel run more true and will allow for the expansion of the rear pod to allow more room/easier access for brushless motors. The front off-set was left nearly the same but the use of flanged bearings means a much truer running front wheel. The 28mm TC wheel uses the same offset as our current 26mm 2-Stage wheel. The 1/8 wheels use the same offset at the current Kyosho/Mugen wheels Jaco produces.

#4 - The large back cut in the wheel was created for several reasons. One was to reduce weight from a design that used effectively 12 spokes rather than the standard 6 spokes that most others use. Also, the back cut allows the wheel to flex very evenly - Take a normal wheel and roll it across the table while pushing some pressure, next try a Prism. With the Prism, you can not feel the spokes as there is even flex/pressure across the contact/compression patch. With the others, you can feel hard and soft spots which will reduce traction and consistancy.

I hope this sheds a little light on the creation of the new Jaco Prism line of rims and tires. I really want to thank Jack for giving me the oppertunity to have some fun learning and designing these rims for Jaco. I look forward to seeing the cars running at the tracks this year... I think we'll be seeing a lot of Prism's leading the way!!
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Old 08-14-2007, 06:55 PM   #79
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cool,that answers my question on the 1/12th offset perfectly.i will be trying them out next weekend and should be placing an order with jack to stock up next week.i really do like the new look and i already pretty much saw the reasoning for the new design.i really like the design and look forward to running and selling them
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Old 08-15-2007, 09:14 PM   #80
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Interesting observation today... the new wheel is lighter than our old dish style wheel. Even more interesting is the fact that our new wheel is 3.5 grams lighter PER WHEEL than the other "big" wheel on the market. That adds up to 14 grams per set, less rotating mass! Wow. Here are some numbers:
4- the number of dollars cheaper retail per pair these tires are than our major competitor.
3.5- the number of grams lighter each wheel is than the other big rim on the market.
7- the number of different compounds offered.
60- the size, in millimeters, they will come pre-trued.

There will be a quiz on this on Friday.
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Old 08-15-2007, 09:17 PM   #81
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Quote:
Originally Posted by Jack Rimer View Post
Interesting observation today... the new wheel is lighter than our old dish style wheel. Even more interesting is the fact that our new wheel is 3.5 grams lighter PER WHEEL than the other "big" wheel on the market. That adds up to 14 grams per set, less rotating mass! Wow. Here are some numbers:
4- the number of dollars cheaper retail per pair these tires are than our major competitor.
3.5- the number of grams lighter each wheel is than the other big rim on the market.
7- the number of different compounds offered.
60- the size, in millimeters, they will come pre-trued.

There will be a quiz on this on Friday.
Dont you ever sleep? LOL

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Old 08-15-2007, 09:40 PM   #82
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Too much cool stuff going on. How is Florida?
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Old 08-15-2007, 10:32 PM   #83
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Quote:
Originally Posted by Jack Rimer View Post
Here are some numbers:
4- the number of dollars cheaper retail per pair these tires are than our major competitor.
3.5- the number of grams lighter each wheel is than the other big rim on the market.
7- the number of different compounds offered.
60- the size, in millimeters, they will come pre-trued.

There will be a quiz on this on Friday.
??- the number of weeks, better yet, days till we can have some in our hot little hands

(This is the bonus question on the quiz)
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Old 08-15-2007, 11:07 PM   #84
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Originally Posted by Jack Rimer View Post
Too much cool stuff going on. How is Florida?
He said there are a lot of cute guys down there.... not sure what that meant...

Josh- changing the rear offset so the 12th scale designers can make the pod as little wider for B/L motors is very smart- not just making a product better for now, but for the future as well. That's an example of what sets a good engineer apart from a great engineer. [/buttkissingsession]

Race on!!
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Old 08-16-2007, 06:48 AM   #85
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Quote:
Originally Posted by Jack Rimer View Post
We discovered something interesting over the last few months. Many local shops have claimed that our double pink and double pink/orange combo was too aggressive. They said "magenta" rears and "cyan" fronts from another brand were much easier for the locals to hook up with. So we went out and bought some of these tires from a number of sources and discovered that the "magenta" was not a 35 like our double pink, but was a 32 instead. The "cyan" was, in fact, our purple/orange. This explains a lot. We are now offering these two compounds in addition to our current line.
I'm glad you agree that there is some confusion in the marketplace.

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Originally Posted by Jack Rimer View Post
I hate to dodge the question about how hard the orange is, but the hardness depends on what they send us at the time. And it can vary A LOT. We have no control over that process, however if it comes in too soft, we use it for a non-R/C application.

Jack,

On your website you say that you have "total control over the process", and that the batches of rubber are "consistant and true". Obviously actually producing the rubber foam is one part that you dont have control over. So could you please post a chart that depicts what shore ratings the colors are supposed to be.

thanks,
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Old 08-16-2007, 07:07 AM   #86
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We have total control over the selecting, laminating, cutting, glueing, mounting, truing, and packaging process. No one in the industry has control over the foam production process. We are one of only a few companies in the United States who actually produce their own foam tires so in that sense we do have total control over the tire manufacturing process. Just like a car manufacturer does not control the production of aluminum or graphite, we cannot regulate the production of the raw materials.
Pink-30
Magenta-32
Double pink-35
Lilac-38
Purple-40
Double pink/orange-35/45
Cyan-40/45

White-25
Yellow-30
Gray-35
Black-40

All these numbers represent a Shore Type C Asker scale. If you have a Maxmod or similar durometer you will probably get a 5-10 point higher reading. This is fine, as long as you use the durometer to COMPARE the tires YOU run. Do not try to compare to other drivers or to our numbering system. The Maxmod is not consistent or accurate enough compared to a $600 Shore Type C. It does, however, serve it's purpose of grading your own tires in relation to each other very well.
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Old 08-16-2007, 09:44 AM   #87
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[Pink-30
Magenta-32
Double pink-35
Lilac-38
Purple-40
Double pink/orange-35/45
Cyan-40/45

White-25
Yellow-30
Gray-35
Black-40

.[/QUOTE]

I didn't know that the black and the purple are the same hardness, when I use the purple on my 1/12 the car would push but with the black the car don't push why is that? the black I use is the 2 stage so not sure if that make the difference.
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Old 08-16-2007, 10:34 AM   #88
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Black and purple are completely different types of rubber. As I have said before, a durometer is only good to compare rubber in similar "families". I can show you 5 different types of rubber that durometer 30, yet some would hook up and others would spin out before you went two feet. People overemphasize the relevance of a durometer. This is why I hesitate to give durometer readings...I always have to explain why two tires that read the same on a durometer behave very differently.
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Old 08-16-2007, 10:56 AM   #89
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Black and purple are completely different types of rubber.that read the same on a durometer behave very differently.
I got it thank you.
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Old 08-16-2007, 12:15 PM   #90
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Ramyuras,

(Jack/Paul, correct me if I'm wrong) The two main foam families for carpet use vary depending on their rubber content.

Black, Grey and White have very little rubber content. This family of tire wears rather fast. Another characteristic of this family of tire is that it greatly depends on traction compound in the carpet for grip. Since there is not much rubber in these tires, their grip isn't dependent on heat very much. This often makes the tires feel very consistent over a run.

Purple, Magenta, Double Pink, and Pink have quite a bit more rubber in them, although not as much as gas car foam tires. These tires do not wear as fast as the above family. Their grip depends on both traction compound and the heat in the tire. This is sometimes why you'll often find that, for instance, purple fronts will feel different throughout a run.

Another aspect of the differences between these families is pore density. The Black/Grey/White family is much denser than the Purple/Pink family and because of that, they tend to have less grip (smoother surface, less friction against the carpet) for the same shore rating.
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