2014 Berg TE250 (and KTM, Husky) jetting thread

[malcolmzilla]

Changed to a 38 PJ, air screw tuned to 1.5 out.

Much snappier/torquier off the bottom, often carrying a gear taller on sections, also helps the XCW 1st to 2nd gap, less 1st climbing.

So, currently: 38/1.5/n8rj/#2/162

Deleted the thermostat - not sure but if its running cooler that might also assist power? And after 38 hours on the OEM plug, changed it to an Iridium as I was in there. And wanted a look. Yup black and oily! no deposits.

Also did a few other things, not performance related, "tee"d the bowl vents up to airbox (helps pevent stalling in deep water), looped the overflow line up and over the carb, in the event the float and seat bounces a bit, prevents fuel loss, and when my bike lays down for a rest...

93km off ~9litres so economy has improved (gut feel). Could be the riding a gear taller, and maybe the overflow mod - that gave me 2-3 more mpg on the WR.

Dave it winds out ok under load, the powervalve preload and spring are stock, and I don't mind the relative mild "hit". In neutral it seems to rev out cleanly so I think the MJ is sized ok?

Also will repack the muffler, and see how fresh spooge levels go.

[Dobi]

Nice mileage. I gave in and bought the JD kit for my 300SX and am thoroughly impressed. It too suggested a 38PJ and a much leaner main than I was running. might be worth a try.

[malcolmzilla]

An update after 67 hours. OF FREAKIN GOOD TIMES!

Very happy under late summer conditions with the 8/1.5/n8rj/#2/162.
I dont even mess with the air screw...

After lamenting the lack of power for the big loose climbs at Racehorse Creek, SteveO had me try the red spring preload full out (PV action faster, and at lower revs). Seemed too much initially, but now sure helps with the gappy xcw 1-2nd gear climbs. Good at Coulee Springs too.

And a switch to Amsoil Sabre at 75:1 (manufacturer says 100:1) at about 50hrs. Way less spooge and smoke. And quite a bit less $.
Packing was checked at 47 hrs, and looked good not even gooey. Does have a bit sharper note now.

Fuel economy still good around 10km/litre under trail riding, still grumbles nice down low.
Looped the overflow vent up and over the carb body and then out - this may be contributing helping minimize tipover sloshing and bumpy float seating losses.

Could use some advice with the cooler days coming, tho I expect late fall I will switch over to riding the KTM 530.
Upsize pilot and raise needle? Upsize main? KTM carb heater kit in hand to go on shortly.

Also I have not fouled a single plug so far. Only on the iridium now cuz I felt it due after so many hrs... is that telling me something?

Come 90hrs it will get a top end, cometic gasket, water pump reman, clutch check, repack. 85% sure on the SX head then too.

[Shibby!]

You must not trust me.

What have I been saying since you got this bike?

Suspension too soft, red spring, and crappy jetting.

You'll eventually try the NECJ / NEDJ needles and love it (bump the main - 168). Slowly and surely you are moving exactly to where I told you to set the bike up in Moab!

Next time you are out, try mine with the SX head and the above jetting.

I just ordered front springs for mine and will install the progressive spring I already have.

I was amazed at how clicker sensitive the 4CS stuff is.

[dirtyboy]

On my 250 I would keep the same jetting except maybe richen the MJ for those wide open snow runs.

As soon as snow starts hitting the carb it will be running richer than you want.

[malcolmzilla]

Carb heater in, a bit disconcerting drilling into your carb!
Don't know if yesterday was cool enough to trip it: might put the Fluke on it and verify, kinda not very trusting of KTM switches anymore.
Brought my mechanic along he did some trail break tuning to the idle and air screw. Ran well, good economy.
Plan is to bump the main and pilot as temps fall, needle we will see.