Leopard wont rev

[Samir Shah]

pre-09 Leopard converted to digital key start.

Has anyone seen this problem and know what caused it, and have a solution?

Engine was running great all day in practice. Near the end of the day my son turned it off to have a chat. When he went to restart it, a) the onboard starter did nothing b) when started with an outboard starter, it did not sound good, and then would not rev beyond 7000-7500 rpm.

A new battery did nothing. I changed the coil, the stator, and the spark plug. No difference. Still would not rev well.

Any thoughts anyone?

Do the digital electronics go bad?

Thanks, Samir.

 

[Sean S]

I haven’t tried to switch electronic sources on a Leopard, so hard to troubleshoot. Check the grounds and check the rubber bumpers that hold the coil off of the chain/hub guard. Mine backed of a bit one time and was arching across to the small coil wire. Check for compression. Was going 2-wide into a corner off the straight, stuck it and didn’t realize and went off track. Started it again in the pits to warm up for next race and it would not run or rev unless hand/foot was on the throttle to hold any kind of rpm. Later found out that a small piece of the ring broke when it stuck and would hold just enough compression to run at low rpm. I cringed pretty hard when I saw it. From what I saw over the past few months, it looks like you were running it pretty long on the same piston and looking for a DIY or builder. Maybe something to check into.

The name escapes me at the moment, but you can send your electronics off and get them tested as everyone suggests… Russell? Try swapping back to the 07 power packs and see if that helps.

Tony Kart / Leopard

[Samir Shah]

I am going to swap the engines and see if that does the trick first. If it still does not work, then the problem is the electronics. Otherwise the problem is with whatever is bolted to the engine. Maybe the carb?

Samir

[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.

[Samir Shah]

Hi Jim. Yes, I have an inline filter. I just rebuilt the carb, and I checked that the carb was clean under the blue cap. I’ll take it apart and check the popoff again.

Another thing that happened at the same time is that the onboard starter also quit at the same time. So wondering if it is a wiring or ground issue. I did check, and they seemed OK, but I will take a closer look once I get the kart out of the truck – it’s buried under all the stuff (we load it into an Expedition, and then fill up around and on top).

Thanks, Samir.

[Samir Shah]

How about the round thing inside the stator – I forget the name. Does that fail?

Samir.

[Clark Gaynor Sr.]

Check the reeds.

[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.

[Samir Shah]

Solved! (I think).

There were 2 wires that were frayed, 1 was broken, they were also touching each other.

These were the 2 small red wires that are also attached to the larger red wire that goes to the + battery terminal. The broken one was responsible for the intermittent starter problems as well. Once repaired, the engine revved to 10+k rpm in my short test on the stand.

I let them sag and they rubbed against the ground!

Thanks for the input and thoughts.

Samir.

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