Hi there!
First post here, so a nice hello from Austria to all here!
To sum up my issue as short as possible: I have two bikes and three carbs. Currently I am running a 36mm Lectron in my '17 KTM 150 SX and while it is running nicely, especially middle to top, it definitely lacks some overrev - it just falls flat - and some low-end too. My other bike that I am letting my friend ride is a '05 YZ 250 that features a Keihin 19E, afaik this should be the coveted 38mm PWK Airstryker Short Body (right?). And I am having my Mikuni TMX38 laying around that came stock on the KTM and just sucked balls (hence the move to the Lectron back then).
Then I started reading about STIC and Keihin and how everybody is hyped etc., and while I am quite unwilling to buy a full carb just to try, getting just the STIC metering block wouldn't be an issue, I wouldn't even have to pay import tax as a friend from the states could just bring it when he comes to visit. Soo.. what parts etc. would I need to
- get the STIC installed in the Keihin and move the Keihin on the KTM? Air boot? throttle cable (new KTM stock? running Domino for the Lectron atm). Anything else?
- get the Mikuni sorted (most issues seem to be resolved by modifying or replacing the slide, is that true? it really sucked on the KTM) and throw it on the YZ? It's not really power I am aiming for, the 250 has plenty of anyways, just make it run decent on the Yam. Again, parts?
(- the Lectron is 36mm, so afaik it is said to be somewhat restrictive on the 250 / emphasizing rather the bottom end [is that true?] - so it miiiight be an option to throw it at the Yam if I'd decide to turn into a trail bike, but I'd rather have it as a backup for the KTM. But just in case.. what would I need if I were to throw it on the YZ?)
Oh, both bikes are to be ridden on MX tracks 90%+.
Thanks already, kind regards and have a great year everbody!
The yz250 is such a solid and well trusted platform, I would keep the stock setup and only adjust jetting. No need to mess up a good thing.
On the 150sx, you have theee options... going to the aj jetting thread and get the correct needle, nozzle and cut the slide opening 0.5mm at a time.
Or you could leave the lectron... my 150sx came with the lectron, never like it... it runs ok, just too anemic or lethargic for me, plus, it was an older one and I didn't like the imperial fasteners and choke on the wrong side.
My 150sx 2018 with mikuni dialed was better all around.
For motocross, I think keihin stic 38mm is loads better... it fits perfectly (lectron needed an alternative carb boot) although I do run the 2016 oem manifold... its not needed, but the 2016 did run keihin and it matches perfectly.
You can use oem throttle, just file the little nub off the carb top. I am running a aftermarket domino with a quicker pull cam
The forum STIC guy will be along soon to tell you how great the STIC is. Me, personally, I love the Mikuni AJ jetting specs on my 125, 250, and 300. I tried the STIC on both a YZ125 and my TC125 and could never get it working right. Way too much back and forth with George trying to get it sorted. You are basically a beta tester with that thing. It is in a constant state of refinement and evolution. I could not imagine the hassle of trying to do all that from Austria.
Agreed...
I had a really good setting right off the bat, then I exchanged those parts for the updated settings and the wheels came off the tracks.
Mikuni setup well is a really good carb.
Mass hysteria/programming leads people to believe the Mikuni is a paperweight, then buy aftermarket setups to only end up chasing their tail anyway and due to the expense, believe the new set up is better. A well set up Mikuni is fantastic.
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I‘am also from Austria
I switched from a Mikuni TMX38 to a Lectron , and than to Keihin PWK on a Husquarna TC 300 2021
Did all the Mods to the Mikuni and played with the Metering Rod on the Lectron Never get it Right
The Keihin pwk is simple , set once and forget maybe one Main Jet change when if it gets warmer
What is the STIC Metering Block exactly?
Grüße aus Niederösterreich
Servus aus Wien! Yeah I think I will play with the Lectron first (if I find the damn metering rod adjustment tool..) - seems to be running somewhat rich - i can kick it to life without choke at literally ANY temp, slight spooge.. I'll see how much the parts for the Mikuni would be to make it fit for either bike and if it's less than the STIC metering block (it should enhance the PWK's performance big time, so the say - some big threads on it here and elsewhere) start the swapping from there - if it works ok'ish on the YZ - I would take the jetting advice for the 300 from the big Mikuni thread as a starting point) and see from there. if the Mikuni works nicely (and without big investment) on the YZ, I can still decide if I'd STIC the Keihin for the SX or whatever. Too many options, trying to get sorted..
Wo fährst du so ? (Ich als langsamer Wiedereinsteiger in WoDo und Nursch).
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