Stock SM possible carb issue

So I picked up a slightly used (150 mi) all stock SM last week. Had it out for a couple rides.

Two things I've noticed:

- when running hard and coming to a stop, it takes awhile for the idle to come down to normal. A couple of times I've come to a hard stop and I can count 1 or 2 Mississippi before idle returns to normal. Stuck slide?

- Occasionally when I'm between gears and getting ready to accelerate.... if I downshift it runs strong. If I don't downshift (but not really lug either) there's some definite jerky hesitation when I try to go to larger throttle openings. This particularly symptom was much more prevalent at altitude today. I was in SoCal on Angeles Crest and surrounding roads so my alt. was 1500'-6000+ and back again a few times, temps in the 80s/90s. Perhaps I'm asking too much of the jetting -- I've only touched carbs on inline fours.

I have the parts here to do the 3x3 and rejet with stock pipe but I am still breaking it in. It has about 600 miles now. The only thing mechanically different than stock is that the canister has been removed, and I'm pretty well certain that was done correctly as I used the posts here as guidelines and I've done this on other streetbikes without ill effect before.

The air filter looks reasonably clean.

Any suggestions? I hate to proceed with rejetting while there may be other issues.

Other than the above it runs great and my chicken strips are all gone :excuseme:


Sounds like normal lean factory jetting to me.

The hanging idle is just too lean on the mixture screw.

And yes 1500 to 6000+ feet is expecting far to much from any carb, although there

is probably a middle ground where it is at an optimum setting.

You should do the 3x3 as soon as possible, running in or not.

For jetting you need to decide on what altitude you spend most of your time at, and jet for that.

I suppose you could jet it just a little rich for home if you spend time at lower altitudes, bearing

in mind it will get progressively leaner as you climb.

I live and ride at sea level, but I noticed earlier this year while using an Edelbrock carb that even

a climb off 500 feet affected the running, on returning to that area later with the standard BSR 36

that it made no noticeable difference.

Neil. :excuseme::bonk::busted:

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