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So who switched from a carb 300sx to a FI 300sx? Thoughts?
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Buddy has a new one. It had some issues from the programming, kinda had a bog down low and it fluttered up top. Sent the ECU to twisted and now runs on T2 and overall is a much better bike then it was.
I have a 23'. Also had a bad ass mod 17' TC 250 which screamed.
I have about 26hrs on the 23' 300 now, and it's coming around. PC full exhaust. My initial peev was it came on a bit too hard in the aggressive map w/ no over-rev. The White map was just too tame.
Had a guy on the east coast reflash the ECU, and I was not impressed...(killed all of the fun) Had him reflash to stk, but I guess it was an updated flash from KTM cuz it seemed to run a bit better.
Most recent mod is a 7oz flywheel weight which totally helped. Better traction and more over-rev.
It's pretty dang good now, so I'm afraid to try Twisted's reflash.
Steathy will make a custom flywheel weight so I may try a 7.5 or 8oz.
6500 spring conversion is an absolute must.
How did a flywheel weight give more over rev?
24 300sx. Still have a 350 and a 150. Love the bike. However I do wish there were 3 maps. The aggressive map is too much for me. The slower map is great for lap times but not fun enough. I love the forks. I did not like my 19 350 fork . I have ridden a 2013 carbed 300sx. Quite liked it. But this 24 is fantastic. I put a 50 tooth on the rear. I rarely use 2nd . 3rd is the money gear.
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Not a 300 but have had all 3 recent generations of 250SX’s (18, 22 and 24 now), I have to say I don’t think I have a preference of any over each other. I think the 18 was probably the fastest, 22 best handling and best suspended and 24 is the smoothest. If I HAD to rate them? 22>18>24
It didn't
I spent 15 minutes on a FI smoker and I said damn I can't wait to ride my bike again lol.
The white map only allows the PV to open 80%.
I have 65hrs on my 23 300sx. Mostly Mx but some GNCC type riding. First 40 were with stock mapping, FmF fatty pipe and 50 tooth rear. Map 1 was dirty/ rich= safe map… map 2 was much better but I felt what I thought was detonation in deep sand under heavy loads. Started mixing c12 with non ethanol pump 50/50. Engine was crisp in map 2, hit pretty hard for a 50 year old, after a few laps it can be tiring. I had John Ross @tpituning.com remap ECU. Now map 1 is my main map, great setting for all riding conditions, smooth yet strong, great off idle, through the middle & good top end over rev. I asked for a richer settings on map 2 just to be safe for deep sand riding. After the remap, I was tempted to go back to a 49 rear, but stayed with the 50 so I could use 3rd gear more. No opinion on Aer fork as a I have ConeValves, although I have used the newer Aer”s in sand & I got them working decently. The newer generation chassis is stiffer but also more precise, I have no problems with chassis, slight front end push on hard flat turns but that can be mitigated with fork height adjustments. I have owned 3 carbed Xc300”s that I had setup for GNCC/ occasional Mx. The carb adjustments and gearing was always a compromise on those bikes… I still feel my 350sfx is an easier, more consistent bike to ride for longer motos but I think I am faster on my 300SX.
Appreciate the feedback boys.
I remember the hype being DFI with all of it's promise. FI is not that. I hope the majority of bikes are indeed trouble free.
With rebates already considerable, why not go retro and buy a carb airbox boot...etc. Then you can tune the power and avoid all the mapping and electronic (potential) hassles. TPS carb for best outcome, I'd think.
My '24 low hour 300SX came with custom re-flash, PC pipe and hybrid fork kit. It's pretty sweet. But, I immediately found myself wanting to try my YZ front end and STIC Super X carb off of my 200SX. No hope for me. LOL
Sure you could do all that to fit a carb on a tbi bike but how do you deal with the electric power valve? I’m just guessing but, there would have to be a lot of sensor fooling, and you would still need a tps to tell the power valve when, and how fast to open.
There are ppl doing it, some use resistors for the fuel pump and TPS, but there are also degrees of what can stay in place, but not wired up. The PV will still do the same mapping based on rpm.
I guess there are minimal changes, as well as full retro fit, 'Cept for the ePV. More than one way to skin a cat I guess.
I’ve had a 20 and 21 300sx, both were built by twisted with decked heads and minimal porting. I’ve got 69 hours on my 23 300 now, new piston was installed at 55 hours. It looked good but was def a good time to change it. My first 50 hours was stock mapping, in stock trim I like my older motors more but it wasn’t a huge difference. I like to run 3rd as much as possible so I want my bike to light up fast with minimal clutch. I felt my older ones were a tad bit faster and got into the pipe a tad bit faster. The last 19 hours I’ve been on a twisted map and now I rank the efi 300 as way better. The Twisted map got my bike to hit harder which I like, basically giving it the same hard hit down low but with more top end than my 20/21. The efi also runs cleaner at all rpm’s and it’s nice because it’s way more consistent at different tracks/temps. I find they also vibrate less with I absolutely love. Side note, I hopped on a 22 yz250 a couple months ago and literally couldn’t ride it because it vibrated so much, I did two laps and had zero interest in continuing. That really bummed me out because I actually don’t like KTM, I’m just forced to ride them as I find their two strokes to be superior to every other manufacturers.
"Literally" couldn't ride a YZ250 because it vibrated too much? Ohhhh boy...
Why are KTMs superior again? Locked tech that forces you to pay a bunch of money to tune? It sure isn't suspension, horsepower, or even weight anymore.
No joke, it is another member on here’s bike, cclay47. I guess I should’ve said didn’t want to ride it vs couldn’t. Do you own a new Austrian two stroke and have jumped to a yz250? It’s alarming how much those fuckers vibrate and I had no interest in anymore of it.
I've ridden every bike you see at the track (except any electrics) and owned/raced a 450 last year. Back on a YZ250 now. Whatever extra vibration it may have doesn't even register with me.
I've seen vibration mentioned before and folks talking up the counter balancer on KTMs... I don't get it. I've ridden 150, 250, and 300 KTMs and I simply didn't notice that part of it at all. I'll try to spin a couple laps on a KTM this Saturday... It's been awhile.
I don’t ever remember it being an issue on my 2006 rm250 that I rode from 2015-2017, It just seamed normal. I’ve been on the newer ktm two strokes since 2017 and now it’s crazy how much I notice it. Even my 1996 cr125 bugs me with how much it vibrates. Only reason I brought it up was the 23 300sc is noticeable how much less it vibrated than my 21 300sx.
I think you may notice it less when going from a yz or rm to the ktm and more when you go from the ktm to others. I definitely didn’t really notice less vibration when I got on my first 2017 250sx. I think you have to get used to a ktm without vibration and then go back. Or maybe I’m just sensitive to it?
Pit Row
I agree it’s very apparent how much less the ktms vibrate vs non counter balanced 250’s.
How much that yz250 vibrated
Bad cranks will shake your fillings out but a new yz is a butter smooth engine.
Consider also it has solid bar mounts and no ridiculous counter balancer.
The pre balancer ktms would shake your feet off the pegs at low rpm.
I loved my 23 300, had a mind fart and sold it 🤦🏻♂️. I was going to buy a 24 yzf450 but I think I’ve come to my senses and another 300 is going to be in my van soon.
What jetting were you running in the 20 and 21? I ask because the stock jetting (or any variation of stock using the stock slide) clips the top end horribly. The 250 and 300 are all bottom-mid with no overrev with the stock jetting. The jetting from the long thread in Tech and PV adjustments transform the bike.
Stock jetting on both, I did have twisted tailor their motor work for top end after feeling the lack of it in stock trim as a 250. I think twisted did a good job of adding overrev too. The mapped 23 power does feel like it pulls longer though. The biggest point I’d like to make to the op though is that both the carb and efi motors are very close in overall performance. They definitely feel different as the efi is way smoother feeling but still absolutely runs like a hard hitting two stroke and the difference in feel is not a lot to me. I was very happy after my first ride on the 23 300 that it felt similar to my old bike.
The day after I bought my used '24 300SX, there I was so contented at the track. What do I see? The smiling seller already had his new YZ450 across from me at the track. Keep in mind the satisfaction you provided to the new owner. lol No, that's not your purpose?
I got my 24 used with 14/51. Is stock a 13t or 14?
55 hours on mine now. Maybe I'm lucky but mine has been trouble free from the start. Runs super clean and smooth all the time. Kinda sounds like crap when you're blipping the throttle in neutral, but in motion it's always clean and crisp with no spooge. I had a 21' 250SX before this that was very strong, probably a little stronger than the 300. The 300 is smoother and runs the same no matter the temp or humidity which is really nice. If anything, I'd like a little more low end, I've bumped the rear sprocket up +2 and that helped but I'd rather find a little more power and go back to stock gearing. I'll be trying a higher comp head next to see if that's the ticket, and I have access to a vortex ecu to try as well. All in all though, very happy with it.
I've been going back and forth. Sell my 20 YZ250 and get a 300SX? Or keep the YZ? Wait for a new/improved 300?
14/49 is stock
You will regret selling the YZ. Especially if you are not willing to put money into the 300. The YZ is the near perfect power curve
I would just do anything you can to ride one, obviously opinions are subjective and not wrong, but I couldn’t agree less with Stud. That doesn’t mean Stud is wrong and I’m right, hell I liked the 2009 crf450 so I could just be crazy. I rode a 22 yz250 back to back off my 300sx and like my 300 way more. I mentioned in another thread it really caught me off guard the insane amount of vibration from the yz, being that you ride a yz I’m sure you don’t even notice that. The yz was a really good snappy two stroke that came to attention with very little clutch. The reason I liked my 300 better is at every point in the power it felt like it has several HP less on the yz, racing 450’s I’m much closer on power with the 300. Both bikes had pipes and silencers. I don’t know what he means by a bunch of money. You could easily race this bike stock and I did for 50ish hours. With that said spending $400 for an ecu from twisted def make this the best running two stroke I’ve ever ridden.
I find it annoying and confusing that KTM can develop and test their own bike and then a shop like twisted can make it run way better than they can. Of course twisted is a very reputable tuner but KTM should do better. Luckily for us the 300’s only need a little improvement, seems like the 125’s really did shit the bed.
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