Sparking Clutch: Cause for Concern?

Hey all!

Once again, let me say thank you for putting up with my barrage of questions. I got my motor started for the first time in my ownership (and likely in about a year) the other day, and it decided to celebrate the occasion with a small fireworks show emanating from the clutch. Out of concern for that turning into a large fireworks show, I shut the motor off. Extinguisher at the ready, I started the motor two more times, with fewer sparks on the second start, and only a handful on the third on initial start–as I recall they eventually went away completely.

I was told the clutch was brand new and had never been used, and a quick google search seems to indicate that some sparking is normal as the pads are shaved down slightly when they contact the drum. Have any of you experienced this? There’s no obvious metal-on-metal contact visible, and given that the sparks have decreased dramatically, I can’t imagine that was ever the case.

I appreciate your help on this! I’m chomping at the bit to get it out on track. Assuming the clutch isn’t going to spontaneously combust, that could be as soon as tomorrow.

Edit for clarity: the motor is an LO206

Hey Johnny, always a pleasure. Remind us what motor please?

Hey Richard! I’ll edit the original post to add that info. It’s a LO206 motor. Can’t quite remember the name of the clutch, I know it’s the least popular of the three main ones that folks use on the 206 if that’s of any use. The old owner won it in some sort of race or contest and didn’t use it.

I’ve never had a clutch (Stinger or Hilliard flame) spark without something being very wrong. It’s possible it was semi-seized to the drum from sitting for so long. :man_shrugging:t2:

If it stopped doing it and there’s no visible issues, I wouldn’t worry a ton about it. Just keep an eye on it the next few times.

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That would make sense. I don’t think it was raced at all last season by the prior owner, so I’d imagine that’d be enough time for the clutch to seize partially. I’m sure the friction material makes great sparks, as well.

That’s good to hear though. I plan on starting it up a couple of times tomorrow, so I’ll keep an eye on it. I’d imagine serious trouble would come with other symptoms as well? There doesn’t seem to be any unusual noise or vibration, and the motor revs freely. Didn’t test the clutch engagement, but I’ll check that out on the next series of starts.

That sounds like rust to me. I’d make sure the bearing was lubricated. I use Renewable Lubricants #2 Food Grade Calcium Sulfonate Grease because it is long-lasting, dirt-absorbing, and completely waterproof, but anything you’d use on a trailer axle or bicycle bearing will work.

Interesting, that could explain it as well. I did notice that prior to starting the engine, when turning the chain and sprockets by hand, I could hear a metallic, almost bell-like ringing coming from the clutch at regular intervals. I was told that was just the shoes making contact with the drum, but perhaps it was also due to some rust buildup internally? Speaking of which, does lubricating the bearing involve any disassembly? Or can it be done in place?

Rust is larger in volume than steel, so rust spots are high spots and will catch first as the clutch takes off. To remove them, just drive it normally, remembering to go WOT from a standing start to minimize clutch wear due to slippage.

Some clutches can be lubricated externally with oil, but I prefer to grease them just to get the chance to see the internals once in a while.