[Jim Derrig]

Two observations:  1.  What you want is what is being run at your local track, not the coolest thing available on the internet.

2.  Kids have a knack for finding out what they want to do and can do well, which often doesn’t conform to their parent’s desires.  My dad was an all-state football and hockey player.  I sucked at both sports, but was pretty good at basketball and not terrible at auto racing, sports my dad cares not one wit about.  My daughter is a 4-year letterman in softball, a sport I find only slightly less boring that golf, and my son is deeply into ultimate frisbee (yes, it exists).  If you go out and buy a fancy toy be prepared for your son to hop in and be totally untalented, totally uninterested, or totally terrified, and be prepared to accept that without pressuring him to do what you want.

[Jim Derrig]

My WAG is that you’ve flipped the relationship between the gaskets and the diaphragms on the carb.  The gaskets go on the bottom (closer to the ground when carb is installed) and the diaphragms go on top.  If that’s not it, there could be an air leak, such as from a bad mixture screw gasket.

Once you’re convinced that the fuel path is rock solid, the next culprit is a weak spark from a bad stator (though my experience is with Leopards and not PRD’s)

[Jim Derrig]

In my experience “binding” is related more to mid-corner speed than to entry speed.  My guess is that you are entering the corner, getting axle hop and lifting, and then finding that your exist speed sucks.  Concentrate very hard on maintaing speed after entry, getting on the throttle early and keeping the kart right on the edge of the traction circle.

Also, I’ve had some success decreasing the air pressure in the outside rear tire (drivers left for counterclockwise circuits, right for clockwise) by as little as ¼ psi.  Check your pressure immediately after your next run.  If the outside rear tire pressure is higher than the inside, reduce the psi to make it more even.  I started doing this when I noticed that my axle binding problem was much more pronounced on turns corresponding to the track direction.

[Jim Derrig]

To answer your question, IAME motors were designed from the ground up to be kart racing motors, so they don’t have nearly the room for improvement through blueprinting that the KT-100 has.  You can run competitively right out of the box, and a lot of people do.  Certainly at a local-and-occassional-regional level.

Not sure why you can’t run the PRD where ever you plan to run a Leopard.  The PRD is basically a Leopard clone, and I’ve watched decent drivers in PRD’s have good local success against Leopards.

The Leopard is being phased out so if you are buying new, the X-30 is the way to go.  Neither should be more expensive to run than a PRD.  The X-30 should have a longer rebuild cycle than the Leopard (30 hours versus 20, depending on how hard you drive).

However, there are a couple of new Leopards on sale here: http://www.italianmotorsusa.com/products/leopard-my09

 

[Jim Derrig]

No answer can be universally valid across the entire U.S., so you’ll have to tell us where you are located, where you race, and whether you intend to compete on a local, regional, or national scale.

[Jim Derrig]

I did the skippy 3-day school and that is how I heard about karting.  Basically, everyone who showed up with karting experience kicked butt on everyone else.

There were more students than cars, so we went out in shifts.  During one interval of downtime I was standing next to one instructor when the fastest drivers in the other group went by, all packed together and racing.  The instructor radios another instructor and says “I see the karters have all found each other as usual.”

I asked a few question and was told (1) seat time, i.e., practice, is just as critical in auto racing as in any other sport, you don’t expect to pick up a basketball for the first time and go straight to the NBA and you shouldn’t expect to get in a race car and be ready to driver it correctly, (2) the best way to get seat time is karting, and (3) by the time you progress up to a shifter kart, the next performance step is an Indy car, i.e., a shifter is harrier than an Indy Light.

On top of it all, karting is WAY cheaper than the alternatives. No wonder the F1, Indy and even NASCAR drivers drive them in the off season.  It’a really a no-brainer to start with karting.

 

 

[Jim Derrig]

My very recent experience (2015 Italkart Rapido) is the same as TJ’s:  raising the spindle (lowering the frame closer to the ground) decreased front grip.  Raising the rear axle decreased rear grip.  Basically, if you have too much grip try lowering the ride height.

Why does it work this way?  The laws of physics apply, though the application is self-evident.  My personal theory is that the driver is like a big, inverted pendulum sitting on top of the frame.  The pendulum moves in the opposite direction of the turn (the pendulum has a velocity/vector that is not the same as the kart’s)  This movement transfers weight to the outside of the kart and creates grip.

This effect is particularly pronounced with 6’2″ me.  As you raise the driver relative to the tires, you cause more weight transfer as you turn.  More weight transfer = more grip at the outside tires, particularly the front on turn in and the then more to the rear by mid corner.  Lower the “pendulum’s” height relative to the tire, and the weight stays more centered in the vehicle during the turn and does not create as much grip.

[Jim Derrig]

Before last year’s importer switch, the SIMA track at Italian Motors included a “direct drive” class that featured the IAME Nordam engine.  It’s a direct drive version of the Dragon (a Leopard with a modified cylinder).  I’m guessing from Marc’s description that the OIK might be the Nordam with a power valve.  If so, it will be one fast mo-fo of a motor.

After watching that class for a season, I don’t see any direct drive class catching on any time soon.  And it will not be a replacement for the X-30.

Just starting the things is a PIA, as you have to lift the back end, run with the kart, drop it to “bump” start it, and then jump in before it drives away from you.  So it’s even worse than a shifter (which at least can be started on the stand and then put in neutral).  The IM factory drivers all got one and had fun, but only a couple of privateers showed interest.

Engines like this fill the gap between a shifter and a standard TaG kart.  Rotax tried that with the DD2 and it didn’t get far.  I don’t see much of a market in the US for this motor.

 

 

[Jim Derrig]

jets most certainly can add 2000 rpm if you’re off enough.  start with the simple stuff:  Too rich; fouled plug; dirt in the carb or fuel pump.

[Jim Derrig]

“I’m new to karting and I hope this is going to be a candidate to get started racing. I know its not up to date but is there anything that would prevent me from racing with it?”

The short answer is “no, but don’t set your expectations too high.”

The link below is to a pre-race tech sheet.  Make sure you can check off all of the boxes.

I assume you just want to race at your local track right now and don’t have illusions about jumping straight into a national or even regional racing series.  Your local track probably will require you to have a full-width rear bumper, which most definitely didn’t come standard in 1998.  Also, your local track may or may not have a class for a modified shifter (sometimes called “formula 125”) as that class is not the flavor-of-the-month and you might be the only entry.  My experience is that if you show up with entry money they will not turn you away, though you might not qualify for points in whatever racing series they run.  If you’re just looking for seat time, you shouldn’t care (this is part of what I meant by “funzies” and not competition–you’re not in this for a trophy, at least not yet).

The YZ has not been the engine of choice, but I understand it can be very competitive when properly built and operated.  Main problem will be lack of parts and experienced help from others at the track when things go wrong (and they will).

If your prior racing and 2-stroke experience is at or near zero, you definitely are teaching yourself to swim by jumping into the deep end of the pool.  I followed a very similar path and there were a couple of times I almost quit out of frustration, but I stuck it out and am happy I did.

Tech form:   http://simaracing.com/sites/default/files/pre-tech-certification-sheet.pdf

 

[Jim Derrig]

Some people like it you know–I think of that scene in Talladega Nights–“ooh, the vibrations . . .”  Seriously, you get used to it but it’s never fun.  A fully carpeted Tillet (T7?) takes a lot of it way if you fit in that seat.

The X30 is pretty much vibration free and the X125t is smooth as a turbine.

[Jim Derrig]

You do not need to re-grease the bearing often if at all.  I seem to remember reading somewhere that this was a good idea on the Rotax, but with the leopard, grease it when you install it and then you can pretty much forget it.  You might have random reasons for pulling the drum (e.g., changing the counter sprocket or inspecting the clutch itself).  At that point, throw some more grease on the bearing ’cause what the heck, it can’t hurt.  But in 4 years of running the Leopard I never regularly serviced that bearing, never saw a failure or anything close to one, and never met anyone who had a failure.  The Leopard’s weaknesses are elsewhere.

[Jim Derrig]

I think 35mm is real standard for master’s, so you shouldn’t have trouble finding a replacement.  Try to find one with a reservoir, as this will make your system partially self adjusting.

As for the rear caliper, there is another option beside trying to find another caliper that bolts to the frame.  Current rear caliper design is to bolt it to the axle bearing cassette instead.  Among other things, this lets you adjust axle height easily, as the caliper moves up and down with the axle.

So, you could buy a new, current cassette, a caliper adaptor and the corresponding caliper.  This also would allow you to run a current, self-adjusting rear caliper.  See:

http://www.italianmotorsusa.com/collections/calipers-1/products/italkart-brake-caliper-support

One possible problem:  That old kart runs a 40mm axle and you’d have to change over to a 50mm?  Since it’s a 1999 kart with a YZ, I assume its for funzies and recreation and not serious competition, so this solution might cost more than you want to spend.

[Jim Derrig]

It’s hard to tell without running a finger along the bore, but those bores look pretty much shot to me.  I’d toss ’em, especially since it’s a shifter kart and not a slow poke.

I doubt the calipers are specific to Haase; they likely are generic from SKM or other outside manufacturer.  The Haase importer might be able to hook you up with a replacement.  If not, measure the mounting bolt spacing and try to find something else that will bolt on, maybe something generic by MCP.  The good news is that your disc diameter is probably standard and you can slide it along the axle, so if you can fit something to the mounting holes it should fit to the disc.  The only other issue will be whether the hydraulic lines fit (I had an old Top Kart from that era that used british standard pipe thread fittings-????).  If not, you might have to find adaptors or make new lines.

[Jim Derrig]

The round thing inside the stator is the crank trigger magnet and it can demagnetize, but that is extremely rare and does not describe your situation.

[Jim Derrig]

Do you use an in-line fuel filter?  Cause it sounds like a carb issue to me.  Not really sounding like electronics, especially since you swapped out the obvious pieces.

Incidentally, the IAME coil is almost indestructible, so save your money there. The e-box also is extremely reliable.  The stator not so much, but you swapped it out.  I’d go with fuel and then with mechanical check.

[Jim Derrig]

These are comparatively light and work surprisingly well if you’re willing to pick up the front end yourself.  It breaks apart into the top and bottom halves too, it you need to lift it over the sides of your pick up:

IM Stiletto One Man Kart Stand – Stainless Steel **$50 Flat Rate Shipping**

[Jim Derrig]

see my response to “iame leopard starting issues” close to this topic you just started.

I don’t think the coolant leak is the issue.  As a boat owner I’ve literally drowned motors, pulled them off the bottom of the lake, dried them out, started them up and proceeded to run for years with no issues.  You can check the compression, but I’m willing to bet that nothing was significantly harmed.

I think you are back to square one because you never really left it.  You apparently have a weak or intermittent spark and are a bit over your head because you lack familiarity with the motor, and you need to pull in some outside HANDS ON help beyond diagnosis by internet remove control.  Presently you are in “throw parts at it and hope” mode, and that seldom is cheap or effective.

Walt has offered to help and here is the email for the iame dealer in NJ:

p1-karting@hotmail.com

 

[Jim Derrig]

The answer to your last question is “no.”

Clutches can fail and can make many strange sounds, but I’m guessing the problem might be with the connection between the bendix gear that hooks to the starter and the ring gear that fits over the crank and sits between the clutch and the engine case.  Guessing further, you’ve reinstalled the starter incorrectly.  Try pulling it and reinstalling, making sure it is properly connected to the bendix and that when the bendix is activated it meshes smoothly with the ring gear.

[Jim Derrig]

Hate to make the debate more complex, but I’ve driven the X30, the Rotax (not Evo yet, though) and the Leopard, and the X125t will beat them all.

It’s not even a close call.  Power band as broad as the X30 but with that fat midrange like a Rotax with the power valve set just right.  At practice yesterday I was sticking to the tail of a (decent, non-rookie) shifter driver coming off of corners.

Same carb as the X30 or the Leopard (your choice).  TaG USA and IKF legal now too.  Smoothest 125cc 2-stroke motor I’ve ever driven.  No vibration.  None.

Time will tell, but I’m at 12 hours on mine right now and not anywhere near needing top or bottom end maintenance.  And Italian Motors will give you a $1000 trade-in on your old engine.

Only complaints I have is that it drinks a lot more gas than the other motors–almost 6 gallons for a 2-day, single-class gold cup event.  Guess that extra power has to come from somewhere.  And with the built-in water pump and oversized  radiator it takes forever to warm up on cool days (part of the reason for the fuel consumption).  I’ll have to spring for a thermostat next fall.

Seriously, I was an X30 fan until I got ahold of one of these.  If you try it you’ll buy it.

[Jim Derrig]

There was an attempt to race them up here near Seattle when the local zoning guys decided PGP’s permit didn’t allow for 2-stroke karts (there is no sensible explanation, so don’t ask).  It didn’t take off, mainly because of the cost.  Word was that they were close to but not quite as fast as a stock honda and were WAY loud.

[Jim Derrig]

If you’re worried, add Stabil or some other reputable fuel preserver/stabilizer.  Way cheaper than throwing out the gas.

[Jim Derrig]

You’re supposed to use your full real name on this board.

If “some car experience” means you’ve personally overhauled an auto engine, the Leopard shouldn’t present too much of a problem.  As Pat noted, the primary issue is splitting the crank, as the conrod on a 2-cycle is a single piece and has to be slipped on and off the crank pin.  This can be fairly tricky as there are special plates required for different cranks and your local machine shop might not have the correct ones for a Leopard.  You’ll probably need to have the cylinder turned/bored to the next piston size, assuming it still has some meat left.  Rough guess, you’ll be looking at $500-700 for a DIY including parts and shop time, excluding tools you don’t have, and assuming the normally reusable parts are in fact reusable.

You’ll also want a circlip installation tool:  http://www.italianmotorsusa.com/collections/tools-and-machines-specialty-tools/products/125cc-circlip-assembly-tool

Might be out of your price range, but this is killer deal where you trade in your leopard and get a whole new motor including radiator, wiring harness, etc.: http://www.italianmotorsusa.com/products/x125t-mx-engine

[Jim Derrig]

the stuff TJ pictured uses an “egg crate” pattern and is frequently used as sound damper in recording studios.  You can get the pattern in a lighter foam, but the real sound damper foam is denser and probably would make a good side padding.  You can find it online all over.

[Jim Derrig]

Chuck, since I only attend TCKC races for fun and not for championship points, it doesn’t make any difference to me that “TaG” is limited to rotax and PRD, as I just tell everyone up front that I’m DQ’d from any points but I’m the fastest SOB on the track and they’re welcome to prove me wrong. ;)

Which they do. :)

Regarding maintenance and tuning, the pumper carbs used by PRD’s, the X30 and the X125t are very simple to tune:  Two externally adjusted screws and that’s it.  One fuel line.  The Tryton carb on the X30 and the X125t (“heavy” version) seems more reliable than the Tilotson–stick in a rebuild kit about every 8 hours.

The X125t also comes with an upgrade radiator suitable for those hot summer day in the Tri Cities.  And the one-piece exhaust doesn’t spurt goo all over your suit (yeah!).

I’d definitely pump Jerry for info on his experience with the X30.

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