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Opinions on these "custom-50m-metering-rods"

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GSP7:

--- Quote from: Kenth on January 19, 2026, 11:35:24 AM ---M4 rods w/suffix J are equivalent of early no-letter rods.
M4 rods w/suffix K are single taper and step to .026".
M4 rods w/suffix L are equivalent of 4M "B" rods.
M4 rods w/suffix M are single taper and step to .036".
M4 rods w/suffix P are single taper (steeper than K rods) and step to .026".
M4 rods w/suffix S are smooth single taper to .036".

--- End quote ---

That's a moot point, and irrelevant to the original question posted

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Kenth:

--- Quote from: GSP7 on January 19, 2026, 04:57:50 PM ---That's a moot point, and irrelevant to the original question posted
--- End quote ---

I posted this info only for "food for thought".

If you think about it a little, if you modify a 50 M rod and remove material to eliminate the step towards .036", it will be richer at the same APT setting.
Hope this answer is useful.

novadude:
I measured a 50M rod out of curiosity.  It looks like the taper goes all the way from 0.050" to 0.038-0.039, and there is only a small step to 0.036".  Does this sound right?  If so, I wouldn't think there would be any major difference between a 50M rod and a custom rod that tapers all the way to 0.036".  As Kenth said, the taper will be steeper, so it will be slightly richer at every point along the taper, but not by any significant amount, IMO.

Kenth:
Here are the specifications on the M rods:

Cliff Ruggles:
The full taper 50 rods don't have a "step" and provide a broader range of adjustment than standard "M" series rods.

I've sold hundreds of sets of them without a single issue.

I recommend going up .001-.002" larger with the jet size with them.  Mostly because of the full taper and the fact that this new fuel requires about 5-7 percent more of it, all else being equal.....hope this helps some.....

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