Notice for IAME 175cc Shifter owners regarding HB-15A Carb

April 11, 2019

Notice from IAME regarding Tillotson HB-15A Carburetor Adjustment Screw identification.



Thank you for posting this. I see a fair number of carbs come through my shop that have the screws reversed. Older X30 (HW27A) carbs had the high speed screw marked with a tiny “H”, but newer units do not. I always engrave H and L on the screws of any carb I service. I put a note/picture on my website addressing this.

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I did this on mine the first year I ran it and wasted a few sessions trying to figure out why it wouldn’t run right.

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I just got our KA, so I will check it before we run this weekend.

Except my KA100 came with an HW-33A carb.

That’s the carb used in Australia I believe?

@KartingIsLife The HW 33A is the currently used carb in Australia.

HL 388A is the original that was supplied at the very beginning.

I thought the US used the same as we do now. Wonder what the difference is. The HW 33A carb can have the mixture screws mismatched also, so worth a check.

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US is using the same carb now. My motor came directly from IAME USA West and has a release date of February 21, 2019. So it has to be what they are running now. I still checked, and they looked correct.

Is this the 175 SSE carb? image

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At this point I think the only thing I know is there’s a typo somewhere :joy:

The model number matches the 175’s carb, but the picture doesn’t :man_shrugging:

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