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I have been keeping an eye on a few locally…Lower hrs the better for sure…most for sale are ready for a complete overhaul….I had a brand new 22125Sx, put 20hrs on it, with the jetting off this thread….sold it for more than I paid for it, should have kept it, now that I have been riding my 93 Cr125 I feel I would appreciate it more…Vet/+50 125 races seem to be gaining traction in most regions….I”m thinking I may hit the World Vets this fall, they have +50 125 class…..my 2 300sx”s have been magnificent, especially after remaps but that is a different thread…..
Ive ran up to a 480 on my YZ, but took away some over rev. So 460 for summer and 470-480 in the winter.
Also running a richer jet needle s7 (s9 being the richest) you may be able to get away with a leaner main. 420-430 I think is STD main for the YZ.
The setup you describe (42-74 clip 3 with the s7 ) would certainly make it richer in the middle (compared to a 42-74 with an S4). However, with a small-ish 460 main, the S7 makes no difference on the top end as the main jet becomes the constraining factor. As AJ said, the Austrian 125/150 likes a lot more fuel on the extreme top than the YZ125's do. Hence why the specs in this thread are in the 500-540 main jet range.
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Hey all,
Coming back in to see what your guys suggestions are for the mods im about to do. Currently im running the spec thats in this thread on a 2020 ktm 150sx
510 Main
32.5 pilot
42 - 74 needle clip 2
AS 2 turns out
PV 1.75 turns in from all the way out.
Also got the pro circuit r304. Bike run amazing as of now. However I'm thinking of adding the pro circuit platinum and the vforce 4r reeds. Would these require a jetting change? And if so in what direction. Im more concerned with the pipe as i heard the reeds dont need any change. Also as a side note:
- do you guys recomend the rad valve or v force 4r?
Thanks.
The Vforce will likely make no change since they are pretty much identical to the stock reeds. I’ve use many different pipes and never really needed to adjust jetting. But I never tried the PC pipe. Doubt it would require much jetting change.
Never tried the Rad Valve on these bikes. You will have to let us know how that goes.
Thats good to hear, since the bike runs so well right now i didn't want the changes to mess it up haha. I've heard lots of good about the pro circuit system on the 150's so ill try it out and see how it goes. The r304 itself was a big improvement.
Nice bike!.. i have the same 2020 with almost same jetting . sea level 50-65F range temp 520, 35 , 42-74 pos 2, AS 1.75 . PV 1.25 and in few days im gonna try the red spring and Boyesen Super stock reeds .
For the 185-200lbs owners in this thread….if any… rear shock spring rate?
193 nude…
I use a 4.8
Better than the 4.5 and the stock spring (4,2?) way too soft
Excellent… thanks….going to look at a 22 150SX this week…like I need another bike😂
Last year i was on 190lbs and i put on my 150sx a 4.4kg rear spring Race tech with great results and 140psi in front fork , now im 171lbs and i had a hard time getting the right sag without gear, the best i could get is 103mm sag , i think with full gear i reach the 105 mark . Stock spring is 39 NM
Are you guys using a 32.5 pilot in the 150sx ? I am down to a 25 pilot in mine with the cut slide. I could see it working in the125 but what is best for the 150.
Hey, heads up there’s a 4.8 for sale in classified and it’s not me
20+ shipping that’s cheaper than the six beers you’ll drink on the way back from the track
In summer sea level i use 32.5 pilot with the #5 slide , no notch. Below 75-70 temp i change to 35 and my bike when temps reach to 40F my air screw is at 1 turn and maybe i can drop 37.5 but that temp is early in the morning. Usually i set the Air screw at 1.5 turns
Just picked up a 10hr 22 150SX…. Can anyone confirm, looks like it came stock with the S4 nozzle, not the S7 the 125 comes with?
Yes, should be the S-4 in there. Only way to know for sure is t to pull it out and check the stamp.
6hr round trip yesterday for this 22 150 with 10hrs on meter….stoked….already tearing into it and ordering parts😂
Pit Row
Thanks… I will be pulling carb off this afternoon…I”m going straight to the known jetting in this thread…I will cut slide myself, just need to order the correct needle..going to stay with the Aer forks, need to at least get a spring for rear shock…3.9 not going to work for my 190lbs. Unfortunately I gave away all my stock 350 springs from that generation…chassis going to get a greasing while I”m at it….
We”ll what do you know….
I would go with a 45Nm spring for 190 lbs with no gear. I am running a 42 on my 150 and at 185 I am kind of right at the point where I could go with a 45 if I was any heavier.
The specs on page 1 are where I would start on your 150. They are pretty much exactly what I am running in my 150 at the moment. As for the 2022 bog, I ended up needing to go to xx-75 needles to tune that out. Keep that in mind if the xx-74 needle gives you the bog. The specs were developed using 40:1.
Also, double check that your float is 8 - 9mm while you are in there.
Thanks for your input…I planned on running 40:1, so we”ll see how the jetting works for me..just ordered everything I needed for the carb…debating on picking up a used traxx shock, they are priced pretty good being the older chassis…I have no problems with the stock shocks once the proper spring installed…what gearing are you running? I read 14-50 helps the broaden the shift points?…
My bike is a TC125 that I put a 150 kit on. I am still running the stock 13/51 gearing from the 125. I know guys talk about the 150 having the torque to pull taller gearing, but I don't really see it. But I haven't tried to be sure so....
Maybe I should ride it and decide…the stock gearing on this bike is 13-48…I have an MxA mag that states the stock gearing is ok but most preferred the 14-50 as it’s slightly taller…
With the 13/51 I am getting really good 2nd gear starts, can carry 3rd in corners where momentum is up, and drop to 2nd for tight inside ruts, which all seems about right to me. Most jumps are 4th gear with some bigger ones or longer stretches to the corner being 5th. If I was running 13/48 or 14/50 I imagine I might need 1st on starts or 2nd with a lot of clutch slip and then I'd be spending a lot of time on the track trying to stretch out 2nd and 3rd with lots of clutch. For reference, my bike has like 85 hrs and is still on the original clutch! Kinda crazy for a 125/150, so I guess you could say I am riding with a style that is more about lots of shifting and being in the correct gear than it is about hammering the clutch to stretch out taller gearing. So it depends on your track types and riding style preference. I also stayed with the stock 14/49 on my 250 when I converted it to a 300 and some guys say the same thing about running taller gearing on those.
Don't waste your money on a Trax. I had it and a 22 350 and I sold the bike with the trax and put the 22 shock on my 18 250 2 stroke because it was just as good if not better. For this chassis a ride engineering link and the sag set to 103 is the way to go. I have an extra one I'd sell if you're interested. Its been in my gear bag for a few years so it will need the bearings and stuff from your stock one. I noticed it calmed down the rear swap into turns with a lot of braking bumps and made corner exit with sharp square edge bumps not as painful. On the gearing I liked the stock better, the MXA gearing was shift city and having to remember what gear you're in after down shifting 47 times into a turn makes it hard to ride fast lap to lap when you start getting tired.
Ok, appreciate your input…I will leave stock for first few rides & see how it feels… I prefer not to have to use first gear also….
Thanks for input AJ…I never have had a reason to buy the Traxx shock, I have been on KTM”s for 10 years..usually Factory Connection does my suspension…I”m getting old and like to spend $😂…I figure the valving is on the lite side for my 185-190lbs ..I will replace the shock spring with a 45kg and see how it feels…thank for the linkage offer….I will let you know….
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