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jim rogero
Joined: 18 Jun 2005 Posts: 1030 Location: United States, Florida, naples
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Posted: Thu Aug 05, 2010 4:34 am Post subject: |
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| angus hunt wrote: | ihor, you need to go to work with ron from Engine Services. he's got it figured out, but you and him will have to do some engine testing getting your motor right ($). or better yet, just come to jrs with us!
like jim said, it's very important the time it takes in building rpm's. that's the big difference in a 'minimax' motor compared to a stock one. our really good one jumps 100 rpm's in fractions of a second after 12000 rpm's. and remember what i showed you (from what i learned from OGP)at new castle with it on the stand. you gotta get that jump almost instantly or your jetting isn't right.
jim, i haven't heard that before about turbo in jrs, but if so, then ihor and i are totally wrong. if that's the case, then it's just part of it, just like learning to tune the chassis. but i was under the impression it was only a minimax thing, and others who i assumed know have supported that thought. and with jrs not being fixed gears, i wouldn't think it would make such a huge difference. but i'll be the first to say i don't know much. hope to meet you at the track some time, jim and see the kids race, richie (angus' dad) |
Angus, There are alot of things in Jr. that are easier than minimax. The more HP you have, the mistakes made are more "forgiving". If you follow some of the good drivers in the past that did well in the cadet and less HP classes, you will see that when they move up they tend to do well.
I think this is also due to the fact that the faster karts are easier for the dads or tuners to tune. |
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Bill Wright
Joined: 27 Jul 2001 Posts: 1004 Location: United States, Florida, Panama City
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Posted: Thu Aug 05, 2010 8:09 pm Post subject: |
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Spec Gear. Spec jet? That's how the Canadians handle it........ _________________ Bill Wright
Formula Kart Productions, Inc "SERIOUS FUN!"
Exclusive Promoter / Owner of the Florida Winter Tour
www.floridawintertour.com
Lo Rider Casual Kart Apparel |
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Tony Tesoro
Joined: 21 Aug 2007 Posts: 81 Location: United States, Florida, tampa
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Posted: Fri Aug 06, 2010 4:34 am Post subject: |
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Or the easiest answer would be test, test, test and seat time, seat time, seat time  |
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Scott G Evans
Joined: 27 Jul 2001 Posts: 101 Location: United States, Palo Alto, CA,
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Posted: Fri Aug 06, 2010 6:56 am Post subject: |
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| Bill Wright wrote: | | Spec Gear. Spec jet? That's how the Canadians handle it........ |
Used to be that way in the US as I recall...
So now you have carb doctors and master tuners holding rein on the Minimax class. The newbie racers are dead meat and the class will turn into the big team racers. Silly. Spec the gear, spec the minimum jet and check it often.
Scott |
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Mark French
Joined: 28 Jun 2004 Posts: 122 Location: United States, Texas, Sachse
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Posted: Fri Aug 06, 2010 9:06 am Post subject: |
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I totally agree Bill and Scott. Two things I wish Rotax would look at. The first is to simplify the national motor package. I think the motors should be run as is from the factory. If you want to change squish then ok but make it one carb (8.5), one air box, one needle and one set of floats. Also consider a minimum jet for each class. Second is to narrow down the amount of time spent a Nationals. Rotax has done an awesome job moving the nationals to the summer but consider one practice day and go straight to racing. I know the days prior to the nationals are “unofficial” but consider having the track closed to all rotax and only allow rentals and maybe track club members only.
Just my two cents. Sorry didn’t mean to high jack the “turbo” issue. Down here in Texas we call it boost  |
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Ted Murphy
Joined: 17 May 2010 Posts: 40 Location: Canada, ontario,
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Posted: Fri Aug 06, 2010 4:15 pm Post subject: |
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| Bill Wright wrote: | | Spec Gear. Spec jet? That's how the Canadians handle it........ |
Being a Canadian, I can attest to what Bill is quoting. I have not witnessed any "turbo" effect up here and with spec'd jetting (rich with a 155) I doubt we'll ever see it. While I was initially pissed upon hearing of spec jetting up here - I love the science of set-up - it sure levels the playing field. Now it's up to the driver and chassis set-up (ala lot's of seat time). |
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Alan Dove
Joined: 10 Jun 2005 Posts: 983 Location: United Kingdom (Great Britain), not usa state,
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Posted: Sat Aug 07, 2010 4:50 am Post subject: |
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Having seen the investment that teams make in getting a Rotax engine working including part matching, endless hours on the dyno, and actual testing it's hard to argue that the class offers 'equal' performance. Performance is being found within the engines, and it's the same in any class.
I think in reality what single-make racing can promise is a consistent set of rules and equipment that can last year on year and brings together professional and hobby karters within the same program. Once the words 'equal' and 'fairness' get brought into the equation the waters are muddied. And if Rotax were 100% confident no time can be found in the engine they wouldn't require the rotax world finals to use factory selected motors. Even if the engines are relatively equal it does take a lot of investment going to test to find the sweet spot. That all costs money which many don't have. This isn;t Rotax specific, it's the same in all classes.
Slight off-topic I know  _________________ Karting1.com - Home of the most awesome karting stuff on the net. |
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angus hunt
Joined: 03 Nov 2009 Posts: 76 Location: United States, Georgia,
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Posted: Sat Aug 07, 2010 5:20 am Post subject: |
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hey jim, just got back for a couple days at OGP getting hooked up with our new tony and junior package and you are right, there is turbo in juniors for sure! BUT it's not the same, and it's easy for the driver to get. angus could get turbo whenever he had enough room to get to about the right rpm to then make the jump. it's a burst, but not nearly as drastic as the minimax burst.
i think the only way to limit the minimax turbo is with a rev-limiter. we can get turbo with a 148 main jet, so limiting that isn't the fix.
someone in canada will get it soon. i'm sure stoll is getting it. _________________ www.angushunt.com |
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Ronnie Warbington
Joined: 26 Jan 2010 Posts: 6 Location: United States, Georgia, Atlanta
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Posted: Sat Aug 07, 2010 7:32 am Post subject: |
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If you need some help with Turbo give me a call 404-556-5507 _________________ Engine Service Motorsports |
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Mark Spikes
Joined: 24 Sep 2003 Posts: 223 Location: United States, Washington, Fox Island
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Posted: Mon Aug 09, 2010 3:59 pm Post subject: |
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MF: >> one carb (8.5), one air box, one needle and one set of floats<<
I totally agree.
When I started in the Rotax 10 years ago it seemed to me all we tuned was just main jet, needle....um, that was about it engine wise (SR. Motor). Only TUNE.
Now, one has to CHOOSE the correct performance product and, hope for the best, and then TUNE that. Now it is Choose AND Tune.
CHOOSE, one or the other, or combination of:
2 airboxes, 2 clutches, 2 needles, 2 float types, 2 venturis, pipes with different bends, green plug or white plug coil, old vs new, endless range of float heights by the bend method, endless range of slide heights, different types of restrictors, old vs new motor due to differences either inherent or built in, big squish or little. I know I am forgetting some.
The above, giving some type of advantage - based on atmospherics, track, driving style, chassis, pull of gravity from the moon/sun. To opinions that none of the choices make ANY differences to the choices make HUGE differences - and ranges in between.
THEN (in some cases):
If you have a Spec Gear (MiniMax). Instead of adapting the gear to the track, by simply selecting an appropriate gear, one has to adapt the track (ie via chassis/motor/carb/driving style) to the gear by working around the gear as it has now become an obstacle to performance instead of a component of performance.
I'm glad flying airplanes (737) is a lot simpler.
MHO(s),
mark |
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Michael Maurini
Joined: 11 Jan 2003 Posts: 286 Location: United States, Indiana, Indianapolis
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Posted: Tue Aug 10, 2010 5:43 am Post subject: |
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| Phillip J. Arscott wrote: | | Michael Maurini wrote: |
It is hard to out drive someone in a Rotax.....You need to out tune them.
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I hope you are joking.
In Rotax driving and chassis tuning are much more important than engine tuning.
I've seen countless people complain about their engine, myself included, (mainly complaining about bottom-end), when in reality their chassis is not set up correctly or they have the wrong driving style/line.
In order to be fast on the straights you must come out of the corners fast.
Also don't forget about the huge affect of the draft in the mini and junior classes. |
Phillip,
I meant that you need to out tune them in regards to the overall package....Kart has to be perfect as well as the motor. I wasn't pertaining to one more than the other. Sorry for the confusion. _________________ Mike Maurini
317.270.8723
Mike@RaceTechDevelopment.com
www.RaceTechDevelopment.com
_______________________________________
My opinions and thoughts are my own, and are not shared by any organizations or companies that I may be associated with. |
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jim rogero
Joined: 18 Jun 2005 Posts: 1030 Location: United States, Florida, naples
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Posted: Tue Aug 10, 2010 8:19 pm Post subject: |
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| Michael Maurini wrote: | | Phillip J. Arscott wrote: | | Michael Maurini wrote: |
It is hard to out drive someone in a Rotax.....You need to out tune them.
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I hope you are joking.
In Rotax driving and chassis tuning are much more important than engine tuning.
I've seen countless people complain about their engine, myself included, (mainly complaining about bottom-end), when in reality their chassis is not set up correctly or they have the wrong driving style/line.
In order to be fast on the straights you must come out of the corners fast.
Also don't forget about the huge affect of the draft in the mini and junior classes. |
Phillip,
I meant that you need to out tune them in regards to the overall package....Kart has to be perfect as well as the motor. I wasn't pertaining to one more than the other. Sorry for the confusion. |
I have "over tuned" and wanted them to run the race Monday morning.  |
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jim rogero
Joined: 18 Jun 2005 Posts: 1030 Location: United States, Florida, naples
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Posted: Thu Aug 12, 2010 10:37 am Post subject: |
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| Scott G Evans wrote: | | Bill Wright wrote: | | Spec Gear. Spec jet? That's how the Canadians handle it........ |
Used to be that way in the US as I recall...
So now you have carb doctors and master tuners holding rein on the Minimax class. The newbie racers are dead meat and the class will turn into the big team racers. Silly. Spec the gear, spec the minimum jet and check it often.
Scott |
Scott, Rotax mini max has a "Spec Gear" and always has had... Checked often.... now the spec. jet?? will there be spec on how far you can or cannot open the carb slide?  |
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Rob Lewis
Joined: 22 Aug 2007 Posts: 32 Location: United States, Texas, Cedar Park
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Posted: Thu Aug 12, 2010 11:20 am Post subject: |
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| jim rogero wrote: | Scott, Rotax mini max has a "Spec Gear" and always has had... Checked often.... now the spec. jet?? will there be spec on how far you can or cannot open the carb slide?  |
They already do, it's called MicroMax.....
-Rob |
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jim rogero
Joined: 18 Jun 2005 Posts: 1030 Location: United States, Florida, naples
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Posted: Thu Aug 12, 2010 5:34 pm Post subject: |
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| Rob Lewis wrote: | | jim rogero wrote: | Scott, Rotax mini max has a "Spec Gear" and always has had... Checked often.... now the spec. jet?? will there be spec on how far you can or cannot open the carb slide?  |
They already do, it's called MicroMax.....
-Rob |
Maybe alittle "micro" in your "mini"  |
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