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Discussion Starter #1
Hi guys,

Good to e-meet you all! I've just got a 2015 Husky TE250 after a 10 year hiatus (been riding road bikes instead but got sick of playing with traffic!) and having a few problems jetting it.

I've reset the bike to stock as per the manual but it just won't idle nicely and when you're cruising/barely on the throttle it knocks/crackles and splutters like matter! As soon as you crack the throttle open it takes off like an enraged squirrel being chased by my spring spaniel! So good haha! Based on the fact that most of my time is spent on green lanes and single track, it needs to run nice on part throttle!

My other question is I seem to have two idle jets, with 38 written on them but with distinctly different hole sizes! Surely all 38's should be the same no? The 40 is quite a bit bigger, which begs the question 'which 38 is the right 38'? haha

Apologies in advance, I'm sure you are all sick to the back teeth of jetting questions but despite searching, finding someone in a similar situation is always tough.

As such, appreciate any advice you can give. For reference, I may try some JD jetting or Lectron later down the line but I'd really like to get it running as good as I can without, at least initially.

As with many of you, its circa 8 degrees average right now and 90% of my time is spent below 300 metres.

Cheers all ;-)
 

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Discussion Starter #2
Should've noted - it has a Pro Circuit end can on it (too loud for my liking these days, but I guess that'll effect jetting?)
 

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1st thing...why did you "reset" the jetting, what was wrong with it?

What did you reset it to? ie what jets needle, clip position etc

You'll probably find the 38 that's closest to the 40 will be the right one
 

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in my opinion if you are only trail riding as I do a four stroke is far better as I have found out with my first 2 stroke they simply do not like to be ridden at slow speed but when you get on the pipe what a bike.
 

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If you want to put it back to factory order 2 new genuine jets they are under £10 each then you will know for sure, that is the problem with a used bike the previous owner probably been botching.
 

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The 'small' 38 is either crudded up or a copy. Japanese / suzuki needles are well worth a try (shit, now the can of worms is open ........... )
 

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Discussion Starter #12
Good question - I put it back to the manual recommendations because it was running a bit rough, but actually it barely that it any better!

I kept the pilot jet at 38 (smaller of the 2) and the pic attached
 

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Discussion Starter #13
The 'small' 38 is either crudded up or a copy. Japanese / suzuki needles are well worth a try (shit, now the can of worms is open ........... )
Haha - love a can of worms!

Ok so its not crudded up but a copy is possible I guess, can't think of any other reason why it would be so drastically different to the 40?
 

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You might be chasing a unicorn here. Almost everyone that moves from a 4/ o a 2/ complains that it runs rough just off idle on a steady cracked throttle. You can make it better but it will never be like a 4/. Have you got another 2/ bike to compare it to?

Check the float height and replace the pilot as above but then go and find a reasonable hill and run the bike up it at the same sort of throttle position and see what happens. If when the engine is actually under load it runs fine then you do not have a problem. KTM 2 strokes do not like running on tiny throttle openings without load.

Other than that, it could be the reeds (they are important for bottom end) or even the CDI.
 

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Discussion Starter #16
You might be chasing a unicorn here. Almost everyone that moves from a 4/ o a 2/ complains that it runs rough just off idle on a steady cracked throttle. You can make it better but it will never be like a 4/. Have you got another 2/ bike to compare it to?

Check the float height and replace the pilot as above but then go and find a reasonable hill and run the bike up it at the same sort of throttle position and see what happens. If when the engine is actually under load it runs fine then you do not have a problem. KTM 2 strokes do not like running on tiny throttle openings without load.

Other than that, it could be the reeds (they are important for bottom end) or even the CDI.
All great info, thanks dude. I'm gonna put a new plug in her, rest to factory with the 'larger' of the two 38's and see what it's like..... the plug that came out is baked black and 'oily' looking so will drop the needle one clip to position 2 (book says 3).

In terms needing a 4/ for trail riding, whilst they're generally 'easier' to ride, I like the easy serviceability of a 2/ and all the other hooligan'ness that goes with them. Plus, I'm not a big lad and the TE250 is fairly light in comparison!
 

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Yes, most people do run it a clip leaner than the manual for the very reason you've described, but don't expect it to go away completely. Basically, ride it like a 2 stroke and there's no problem.

In terms needing a 4/ for trail riding, whilst they're generally 'easier' to ride, I like the easy serviceability of a 2/ and all the other hooligan'ness that goes with them. Plus, I'm not a big lad and the TE250 is fairly light in comparison!
And it's widely understood that people who ride 4/ generally have a lot in common with Julian Clary or Gary Glitter.
 

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Discussion Starter #18
Yes, most people do run it a clip leaner than the manual for the very reason you've described, but don't expect it to go away completely. Basically, ride it like a 2 stroke and there's no problem.

Yup ok mate, good top hear I'm maybe on the right track then!

And it's widely understood that people who ride 4/ generally have a lot in common with Julian Clary or Gary Glitter.
Oh, no comment hahahaha
 

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The larger "38" may well have been drilled by someone being a cheapskate. The holes in the smaller jets need to be mega accurate if you are ever going to make sense out of your carb, what I mean is that if you buy a 38 and the hole in it is bigger than a 40 due to poor tolerances then that would screw up any form of comparison between them. (Drilling jets for methanol is OK apparently).
 
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