250RR Jetting

[BassMan]

I am running a 162 Main, needle in the 1st groove, Air Screw at around 2 1/8 depending, Motul 800 at 3 oz/u.s.gal, 93 octane Marathon fuel. Temps have been around 80F on average and 600 ft. FMF Q pipe and power valve at 2 turns in, runs like the proverbial scalded ape. Tad bit of spooge. I won't change a thing till it cools off a bit.

[BassMan]

I am tempted to try 32:1 with Lucas and the BR7ES with the stock settings. I have a sneaky feeling that is what the engineers used and forgot to make changes to account for the rich mix they suggest. I should note that i am currently using a BR8ES as installed by the factory.

[twowheels]

I'm running stock/AmBeta suggested jetting with Amsoil Dominator at 50:1 93-octane pump gas. This past weekend I managed to find some non-ethanol 90 octane gas to run, I dialed in a NGK BR8ECM short plug to make getting the cap on easier.

[Hyde]

I also switched to the BR8ECM short plug, now you can get the plug wire off with out pulling the tank, cheap and easy mod.

[Gibnut]

Just removed NOZK just to see if my favourite needle would change the bottom end characteristics of an already fantastic motor.

NECJ, pos #2, a/s 1.25, 35p, 165m, BR7ES, gapped @ 0.6mm - tan, Motorex full syn/98ron @ 1/50, 0-300m asl, 5-32c riding temps, 15-100% humidity, Sydney, Australia & surrounds. Summer to winter, I usually only need to tweak a/s & clip position to address the climactic variables above.

Bike is stock (0.5mm base gasket) except for previous owner put 13/48 gearing on the bike, which I reckon is a bit tall in the tight stuff.

To counter this, I thought I'd try the Suzuki RM250 needle - I have used it with success in the past to clean up burbly off idle 300's.

The NECJ always smooths out the mid-top, but I was after a tiny bit more response down low for our usual rocky, clutchy hills and log bouncing

Now stronger with quicker throttle response - so far so good.

[Gibnut]

After being advised elsewhere NECJ 2nd pos. could possibly be too lean for a 250, I have gone to NECJ 4th pos.
Everything else is as my previous post above. With the new 13/50 gearing (from 13/48) this setting works beautifully.
More power everywhere & smooth as you like all the way to the usual NECJ top end. Snappy & free revving like a 250 2-t should be, but not light switch-like power. Jeez, I love this bike!

[GMP]

You could also try the NEDJ (1/2 clip richer) to fine tune. Possibly even the W dia. of each as well for when it cools off.

[DaddyTJ]

You could also try the NEDJ (1/2 clip richer) to fine tune. Possibly even the W dia. of each as well for when it cools off.

I have enjoyed the NECJ needle in my 300 this summer!! Knowing that things will cool off at what temperatures do you suggest going to the DJ, CW or DW needles? I have been riding with the NECJ in the 80's and 90's near 600 ft elevation.

[GMP]

You could also try the NEDJ (1/2 clip richer) to fine tune. Possibly even the W dia. of each as well for when it cools off.

I have enjoyed the NECJ needle in my 300 this summer!! Knowing that things will cool off at what temperatures do you suggest going to the DJ, CW or DW needles? I have been riding with the NECJ in the 80's and 90's near 600 ft elevation.

Same conditions here, guess we will find out. I'd say in the 50s and/or any lean signs. Maybe just a pilot change first, just a guess.

[Hammer]

I have used mine in the low 50s with nothing but a pilot and main change.