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Old 04-05-2008, 08:04 PM   #25726
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Are you actually CA'ing the contact patch or just up the side wall?
He just does the sidewalls Jon
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Old 04-05-2008, 08:42 PM   #25727
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Are you actually CA'ing the contact patch or just up the side wall?

just the side wall, i still have all the steering i can use, it just doesn't roll anymore
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Old 04-05-2008, 08:46 PM   #25728
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He just does the sidewalls Jon

yea what he said,

JB, mike and mikey are going to SIR tomorrow if its raining, i'm THINKING i may go to TRCR

Last edited by skypilot; 04-05-2008 at 08:57 PM.
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Old 04-05-2008, 08:49 PM   #25729
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yea what he said,

JB mike and mikey are going to SIR tomorrow if its raining, i'm THINKING i may go to TRCR
Forget the dirt!! Come munch some carpet with us
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Old 04-06-2008, 12:09 AM   #25730
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I was only asking because I remember at the 2005 IIC when I ran rubber they were very strict about not getting any glue past the crest of the side wall and gluing the outer edge of the contact patch. I wasn't sure if that was a Scotty thing or a common rule on the rug.
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Old 04-06-2008, 01:50 PM   #25731
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Hey Adam thanks for the motor my car was really good today too bad for the rain!
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Old 04-06-2008, 03:58 PM   #25732
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checked out the schumacher uk site, they have black schumacher jumpers any chance schumacher usa will bring them in or should i order from england?
cheers
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Old 04-06-2008, 06:29 PM   #25733
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Now, for those of us that don't know (me), if you'd had the option, could you have run the same tire with a thicker insert to get less tire roll in corners, and stopped the traction rolling that way, or am I guessing wrong as usual?
As far as I know I believe the insert serves two purposes. One is to change the stiffness of the wheel / tire combination - hence soft, medium, and hard inserts. The softer the insert the more traction. This is achieved by the tire being allowed to rollover more with a softer insert. The second purpose is to provide an air-gap, which will effect traction. The larger the airgap - the warmer the tire gets and the more traction you have going around the track. As you increase the "thickness" of the insert - you reduce the airgap and decrease the temperature of the tire hence reducing traction.
So you ask "what if I use a thicker insert?" Well it depends on if the thicker insert is softer or harder or the same. Lets say the insert is the same stiffness - you go thicker therefore reducing the airgap - you should decrese traction and reduce the chances of the car rolling. If the insert was thicker and harder - then I would say you would also reduce the chances of the car traction rolling.
Now - I have to ask because no matter what level of racing you are at you have to ask a few questions. Is the car tweaked? Is the setup proven to yeild fast laps at your local track? Have you checked the car for any broken parts? Does the car traction roll only to the one side and not the other? Are you using the correct tire for your conditions? Have you tried saucing the tires differently? How old are you tires?
So remember to check ride height and droop even with rubber tires. The tires wear differently at each corner and so do the inserts, so your ride height and droop will change. You might be slightly off and once you enter the corners the car now reacts differently and might even traction roll on you. Check these things, let me know what you find and we can go from there or if what I gave you here helped. I hope this gets you started in the right direction.
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Old 04-06-2008, 08:16 PM   #25734
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Old 04-06-2008, 09:15 PM   #25735
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Hey Josh?

Did you end up trying the set-up i posted for you a while back?
Try ringing Metro to see if they can post you a jumper, (they have some in stock)
Phone: 9890 1144
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Old 04-06-2008, 10:03 PM   #25736
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Please tell me a jumper isn't like what we in the US call a "one-sie"!!

If it is like a one-sie someone judt go ahead and ship one to seaball now! lol
I bet they even have plastic feet and a "drawbridge" Chris!
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Old 04-07-2008, 05:44 AM   #25737
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Originally Posted by MagicMarker View Post
As far as I know I believe the insert serves two purposes. One is to change the stiffness of the wheel / tire combination - hence soft, medium, and hard inserts. The softer the insert the more traction. This is achieved by the tire being allowed to rollover more with a softer insert. The second purpose is to provide an air-gap, which will effect traction. The larger the airgap - the warmer the tire gets and the more traction you have going around the track. As you increase the "thickness" of the insert - you reduce the airgap and decrease the temperature of the tire hence reducing traction.
So you ask "what if I use a thicker insert?" Well it depends on if the thicker insert is softer or harder or the same. Lets say the insert is the same stiffness - you go thicker therefore reducing the airgap - you should decrese traction and reduce the chances of the car rolling. If the insert was thicker and harder - then I would say you would also reduce the chances of the car traction rolling.
Steve I donít think this is 100% accurate....a thicker insert will make the tire run hotter and cause the tires to build heat and then possibly get too hot and over heat. A thinner insert with the same stiffness will keep the same tire cooler. When you are dealing with rubber tires you also have to think about how that insert is going to heat up during that run not just the tire. Thicker and harder inserts hold more heat inside them then thinner and softer inserts. For what HVAC is asking a thinner insert or just a softer one of the same thickness might helpÖ.or even just a change to the front shocks like lighter spring with heavier oil would help...less castor too. When you have too much traction and are traction rolling going stiffer on anything suspension or tire wise isnít really the answer. If he were to build his tires with thicker insert then the car might not flip over as soon into the run but once the temp comes up they will be uncontrollable. Think about inserts like tire pressure on a real car they build pressure when you run them and they heat up and if you start with too much pressure you end up with a funky tire that wears all weird and gets too hot and degrades.
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Old 04-07-2008, 09:57 AM   #25738
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This is just what I found from a few years running at SoCal and having to mount up new tires every race day. There weren't any premounts out there that worked on that track so we ran Sorex 36's or 32's and there were a variety of insert and wheel combo's guys were always trying and changing with changing weather conditions. Even though it was an indoor track, it changed dramatically with the temperature outside.

The way I've always looked at inserts are, again, firmness and air gap. Firmness tends to effect the overall grip. Airgap effects temperature and how quickly they heat up. More air gap will get to temperature quicker, but will stay lower due to more air flowing in the tires, cooling everything off a bit and remaining more consistent through a 5 minute run. Where a more full insert will take longer to heat up as there's more material to heat, but it will continue to heat up to a higher temp than a thinner insert due to a lack of ventilation.

I tested this back at SoCal with 2 minute and 5 minute runs and a temp gun. Thinner inserts were up to full temp when I checked at 2 minutes and after 5 minutes were within a few degrees of where they were at 2 minutes. Full inserts were hotter than thin at five minutes, but cooler at 2 minutes. They started loosing grip toward the 3-4 minute mark consistently from overheating. So generally what we'd do is run a thinner insert on warmer days/nights and a fuller insert on the nights we could see our breath while we were sitting at our pit tables. Throw in all the different saucing and warming strategies, and you can see how frustrating and expensive trying to be really fast at SoCal could be.

As for firmness, generally the softer the insert, the more grip unless it was a soft full insert, then it usually overheated and lost grip after the halfway point. I tend to like a thin, medium to firm insert. Gives more consistent temps and also lets the tires work without being too stuck.

It could be very different with rubber tires on the rug though. I never did get the hang of rubbers on the rug and didn't run it with anything but RP30's or CS27 premounts so I never messed with tires.

Last edited by Jon Kerr; 04-07-2008 at 10:16 AM.
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Old 04-07-2008, 10:48 AM   #25739
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Originally Posted by TC3MIKE View Post
That was a 5000mah correct? Well, running over 21 minutes I guess that answered my question!
Core 5000 (which I have) is 23.5mm tall....SMC 5000 is 24.5mm tall.
On my Mi3...fitting Core 5000 is perfect..with probably 1mm or less gap between the bulkhead and the cell, I can still tilt the battery up and slide out with 2 battery slot plastic (that custom cutted to mount the lipo in a fixed area without sliding left and right or forward and backward)...however, if SMC is really 1mm taller......I think griding a bulkhead off a little is a MUST. Core 5000 is perfect fit with a little gap to play with...but still, around 1mm or less.

Yesterday I ran the Core 5000 (fully charged) with SP speedo and 13.5 on Mi3...I think I quit running after 11 minutes because the tire/motor just got too hot (start getting loose), but they are still running....except, I can't stand on the driver stand after 10 plus minute, I have to sit down and need some coffee with Paragon fast...

I bet it will go easily 15 minutes on HARD carpet running with 13.5 system...thats my guess only, may be even more.
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Old 04-07-2008, 10:51 AM   #25740
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Steve I donít think this is 100% accurate....a thicker insert will make the tire run hotter and cause the tires to build heat and then possibly get too hot and over heat. A thinner insert with the same stiffness will keep the same tire cooler. When you are dealing with rubber tires you also have to think about how that insert is going to heat up during that run not just the tire. Thicker and harder inserts hold more heat inside them then thinner and softer inserts. For what HVAC is asking a thinner insert or just a softer one of the same thickness might helpÖ.or even just a change to the front shocks like lighter spring with heavier oil would help...less castor too. When you have too much traction and are traction rolling going stiffer on anything suspension or tire wise isnít really the answer. If he were to build his tires with thicker insert then the car might not flip over as soon into the run but once the temp comes up they will be uncontrollable. Think about inserts like tire pressure on a real car they build pressure when you run them and they heat up and if you start with too much pressure you end up with a funky tire that wears all weird and gets too hot and degrades.
KK...where were you yesterday? Rich and I've got the Mi3 dialed......and my Schumacher TA just gave the STEGAN a woop ass, with ZERO PRACTICE and ZERO SETUP...just cannot out pass the Ryan Phi....we need you to step it up SAT for Schumacher...
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