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Hi,
This looks to be a copy of a Samco. What is benefit of removing the thermostat?
Stock it had no over rev. (12 hrs on bike)- The PC combo just has good increase everywhere, but up top specifically.. sucker just pulls. Keep it pinned she screams.
Sounds freaking awesome too!
What changed on the suspension?
I was at my local shop yesterday that is a pro components dealer. They did pull one apart and said apart from coatings and lack of preload adjuster that it's the same as the 6500 kit.
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Interesting that these TBI bikes don't just use a coolant temp sensor like 4-stroke EFI bikes do. In other words, they are predictive or assumptive on coolant temp, not responsive to actual temp. That might help explain the wide difference in some people having rich fouling problems and other guys bike being crisp and clean.
I looked at some parts diagrams. The 300XC has a 70C thermostat. The 250/300SX does not list the thermostat separate from the pipe assembly or state its value Is the 55C value on the 250/300 SX bikes?.
If you follow Solid Performance on FB or Insta they took some 24 spring forks apart and posted vids/pics of the internals.
The 125sx has a coolant sensor ontop of the hose right over the head…every site I have seen that offers exploded view diagrams is wrong, every one.
Copy no. There are only 2 manufacturers in the world making this Silicone T hose. Moto Hose in the USA and Samco in the United Kingdom. Benefits? It is not a plastic T that is prone to breaking and leaking.
As a life long mechanic I understand flow characteristics and when I looked inside the very complicated stock OEM aluminum T I knew the Y would flow much more efficiently than the T shape making sharp turns. I worked on changing over to the Y shape design and did it a couple years ago all the way to the original 2008 when the internal frame T hose design started.
In the past the KTM thermostat designs have had a radiator bypass built into it that sends hot coolant right back into the motor without going through the radiators making the motor run hotter.
Weather to remove the KTM thermostat or not discussion has been going on for many many years. Some like it some do not. Moto Hose has never made the stock thermostat design hoses we only made kits that eliminates it.
Lots of people and dealers have been swapping out the new plastic design to fix the leaking issues and so far I have not heard of any problems.
This is where the 250/300 temp sensor goes.
Only the 2 stroke 125/250/300 use the thermostat T hose the 4 strokes do not.
Steve- make that a beefy nice aluminum piece for the sensor, these plastic things break and crack.
SHHHHHH dont tell everyone my secret plans 😂
Hahahaahha
These TBI’s are so awesome, anyone want to trade a 23’ 450SXF for my 250SX?
Has anybody had any issues with the electronic power valve actuator?
I have a 2023 300 XC with 5 hours on it and the actuator "went out of its normal range" according to the dealer. The issue was very noticeable with an immediate lack of low end power along with 5 long flashes of the FI light. The bike has been sitting at the dealer for 2 weeks now waiting for a new actuator. Just curious if this is a one off situation or if anyone else has seen this?
Between the forums and Facebook pretty much any problem imaginable has been documented with these bikes. Some are resetting their pv’s every few hours.
As a long time 250 two stroke rider I can confidently say it is the softest 250 motor I’ve ever owned or rode. I like the chassis but can’t stand the motor. Tempted to put a carb motor in the chassis or just send it down the road.
A new YZ is looking more and more appealing.
XC or SX ? I haven’t ridden the 250, but I have a friend who has the SX250 and he feels the same way about the bike as you do. He’s a 50+ Expert and only rides/ races motocross.
There’s no doubt the motors don’t have that 2-stroke “HIT”, but that has worked in my favor to be honest. The motor has a very strong midrange and I tend to short shift it more than most. it pulls 3rd well, even with the 14/49 gearing.
I didn’t like riding my Sx300 at the track, but I absolutely love my ‘23 XC300 for my OffRoad bike. Sold the SX with under 10 hours on it…
I have reset my power valve setting twice and it has made the bike run more crisp from the crack of the throttle, to the 1/4 throttle position. I absolutely love the XC300 motor !
I’m guessing you tried resetting it ? Mine was kinda sluggish and seemed a little rich on the bottom. I reset the power valve and it cleaned it right up ! I have over 80 hours on mine and I’ve reset it twice now. Not sure why I’ve had to do it twice, but it only takes 5 minutes to do, so it’s not a big deal
Yes, 250SX. It’s has no bottom, weak mid, no snap or drive out of corners. I have to ride it like a 125 to carry the same speed as my 2020. Fouled a plug at 9hrs, it was over gapped from the factory so I’m going to assume my tps is not in spec and squish likely wide. Even if both are off they aren’t going to provide a big enough change to make up for the current short comings with how it runs but I’ll check and adjust them if needed.
I’ve been on these since 2015, yz and rm’s before that. 250 A off-road. I’m running 14/48 which every generation until this one has pulled great but it makes the weakness of this motor truly shine. I don’t see how anyone who’s used to riding MX 250 two strokes could be happy with this motor.
Pit Row
I was in the same position initially. I have owned several carbed 250sx bikes as well as a few YZ250's and I loved them. The ECU mapping along with the PC exhaust woke my bike up. Do you ever come up to Washington to ride, you could try mine out....
Who did your mapping? Noticeable improvement on the bottom and mid? Happy with when the pv opens?
Worked great and saved about $25 over the other brand...thanks!!!!!!!
I'm going to be an "oddball" on the PC setup. I'm more of a lugger than a revver and didn't notice much difference. I really was expecting more but was not blown away by any means. I will get to a track early and swap them out to give myself and others a better heads-up review. That way I'm at the same place with the same conditions. Who knows, maybe back-to-back I'll realize that it is a lot better.
I did notice it seemed to run cleaner without the occasional rich feeling, but I also switched to a 7 plug. So did that have anything to do with it??
A few friends commented on how much better it sounded, so there's that.
We are one step closer to making our production run of Silicone Radiator Hoses when the final OEM hose finally came in yesterday for the 250/300 ….. now if the 125 hoses would finally come in.
I had WMR Motorsports out of Florida do it. At the time they were the only company offering ECU tuning and it was a major improvement. They said they were going to offer an app that connects to your phone so you can adjust the ECU but it still isn't available. I'm way happier with it now and it runs way better across the RPM range. A lot of people have compared the power nature of the new TBI bikes to a 4 stroke since it is so linear and torquey. That sounds "cool" but I didn't like it. With the tuning the bike feels like a 2 stroke again which seems appropriate since that is what I purchased.
This was several months ago and I'm not sure if some other companies are now offering ECU mods/aftermarket options. When I was searching for options several months ago GET/Vortex/Twisted all said they had stuff in development.
I think I cooked a head gasket or a water pump today. I was sweep riding an Enduro today and the tre hundo was running pretty ok. Arrived at the entry of a test and stopped to let everyone go. Bike wouldn’t start. It just turned over and turned over and would not start. It was getting a little loaded up but I chalked that up to the weather. It was 90’s, humid and very stale. Had someone push start me and the thing started right up. Got backed to the pit and let it sit. Thing started right up after about 15 minutes.
We went back out to another test and the old girl was getting pretty loaded up. Rode it with no issues. Got back to the pit and figured I’d check the fluids real quick. Low coolant. She took about a quart and we were back at it.
We went back out to one more test to sweep and she did the crank but no start thing again. Popped the radiator cap and she had no coolant. The bike was knocking pretty bad from the water pump so I’m not 100% sure if the pump has failed or what. We’re hoping to dig into it this week.
30.4 hours.
Well that’s a bummer. I’ve had no issues with mine, other than the start/stop button failure. I’m almost 100 hours and I love the bike. So much so, that I bought a 2nd one that’ll I’ll replace mine with after summer.
I did install a Trail Tech fan that I set at 195, which will kick on if I’m climbing sand hills or into some technical terrain with slow speeds. Haven’t had any issues with battery yet either.
There has been some cracked cylinders/water jackets and cylinders are hard to get. Hopefully not the case.
Has anyone tried 2022 vforce reeds in their 2023 tbi bikes or have a part number for 2023.
Comparing OEM numbers, the 2023 250/300 use the same reed block as the 2022 and prior bikes. So, all the existing Vforce blocks should fit. VForce does not show a new part number for the 2023's on their site. That being said, just because it fits does not mean it will necessarily be an improvement. In the 125 thread that JBone has he installed one on his 125 at one point and might have some thoughts about how it affects the TBI bikes. The 125 uses the same reed blocks as the 250/300.
I read on the FB group that a guy said he didn't notice any difference when he installed the vforce.
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