Eating the Reeds

While watching a YouTube video last night a karter was testing the non SKUSA version of the 175.
He wasn’t happy with the tune and mentioned that the motor was “eating the reeds”
I haven’t heard that before, anyone have an idea what that means?

Maybe destroying reed petals for whatever reason.

When I blew an engine the reed was aspirated into the cylinder and ground up. Maybe that’s what it means.

Kind of a subjective term. They’re either cracking, or cracking and being ingested.
That said driving\shifting style and choking habits make a difference to reed life as well.

Letting the motor rev right to where it falls off the powerband tends to be rough on reeds.
Heavy choking same.

To my ear the engine was still running ok, and I’m pretty sure they didn’t get sucked through the engine.
I’ll try and find the video again and link it.
Engine tuning is usually described as lean or rich and this was a term I hadn’t herd before, in relation to tuning.


The comment is made at 12:45, he then goes on to say that they were eaten up in his first session, but not the second.
Maybe they are cracking, I cant get my head around being able to feel that and identify it over other tuning issues.

i think they’re just just saying that reeds are cracking or small bits are chipping around the edge.

it comes about as an air leak - outwards into the carb. The general feeling would be down on power in the lower revs and hard starting.

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This is a known issue with the Iame 175 shifter. “Eating reeds” refers to the (in this case frequent) cracking/fraying/breaking of the reeds. The added displacement of the 175 seems to be the source of the issue (perhaps due to increased crank case pressure?). The situation is worsened if a driver is rapidly downshifting, creating an engine braking scenario.

Thanks, do you know it effect both versions of the 175? The SSE SKUSA version and the regular Iame?
How long does a set of reeds then last?
I have been toying with the idea of buying one to run in our Open Class, and being in Australia where it is not as common as some places , it hard to get much info like this on it.

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If it’s an open class you can run whatever reeds you like? Thicker reed and or different material might be fine, or massaging the cage.

These just aren’t options for folks running the SSE.

“If it’s an open class you can run whatever reeds you like? Thicker reed and or different material might be fine, or massaging the cage.”

Not necessarily, we have to run engines according to there homogenisation documents provided when they are imported/manufactured.
If its a case of changing them every race meeting, at $80 a time (guessing) that will get expensive pretty quick.

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Oh, that’s interesting for sure.

Yes, similar issue on the SSE, though measures can be taken to prevent. Depends on the track and the driver, but mostly on how hard you’re downshifting. The SSE is a great package once you get it dialed in.

Do you have a estimation on reed life?

Again, all depends on the driver. I’ve seen sets last multiple weekends, and I’ve seen drivers that require much more frequent maintenance. It’s usually just the bottom reed that needs to be replaced. We are not required to run the stock reeds for SKUSA, so maybe that would also carry over to the series you’re running?

Eating the Reeds is a band I’d go see

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Ha! Speed metal, I presume?

Maybe even folk or Americana