KTM flywheel weight causing "bog"

opyguy
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opyguy
2017 ktm 250sx.
ran great 4 months ago (last time i rode)
installed a 11oz flywheel weight AND pro circuit PC pipe.
rode yesterday, if I roll on the throttle runs great..however, clutching and dumping out of sharp turns I get a slight bog for a second then comes on the pipe (almost like its too lean)
could the FWW cause such an issue or more related to the PC pipe having less low end?
thanks for your input.
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opyguy
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opyguy 3/21/2019 9:22am
3/21/2019 9:22am
Negative
New main and pilot
Pro circuit specs stock jetting
AJ565
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AJ565 3/21/2019 11:06am
3/21/2019 11:06am
Just the fact that factory jetting sucks can cause the bog along with the weather being different not vs. 4 months ago. It comes to rich from the factory.

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opyguy
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opyguy 3/21/2019 12:44pm
3/21/2019 12:44pm
Honda Man 66 wrote:
Never make 2 changes at once.
winter boredom my man, have to tinker...talked to stealthy, he thinks 11oz could be too heavy in sand (which i was riding).
gonna take it off (5 minute job) and see if it runs fine.
gotta tell you it really smoothed out the power, loved it except for that 1 deep turn....
fourfourone
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fourfourone 3/22/2019 7:43am
3/22/2019 7:43am
my 250sx started to bog before it blew up. Check compression. I had no idea but due to the crappy air filter design on the 2016s the bike ended up eating some sand.
JWACK
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JWACK 3/22/2019 8:46am
3/22/2019 8:46am
I'm a little surprised you felt the need to put a flywheel weight on. I feel like the counter balancer is already a huge flywheel weight on these engines and it bugs the crap out of me! No instant snap at the crack of the throttle.! Kind of a brrrrooooomm instead of a quick Braaapppp!
Then again I lighten the flywheel on my Yz 250s to make them feel more like an RM,so maybe I'm the weird one.
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AJ565
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AJ565 3/22/2019 9:44am
3/22/2019 9:44am
JWACK wrote:
I'm a little surprised you felt the need to put a flywheel weight on. I feel like the counter balancer is already a huge flywheel weight...
I'm a little surprised you felt the need to put a flywheel weight on. I feel like the counter balancer is already a huge flywheel weight on these engines and it bugs the crap out of me! No instant snap at the crack of the throttle.! Kind of a brrrrooooomm instead of a quick Braaapppp!
Then again I lighten the flywheel on my Yz 250s to make them feel more like an RM,so maybe I'm the weird one.
You're not jetted right if your bike does that. Mine is instant and friends that ride it hate it because they are used to theirs not being jetted right (they don't feel like ordering the parts to do it).
JWACK
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JWACK 3/22/2019 9:59am
3/22/2019 9:59am
JWACK wrote:
I'm a little surprised you felt the need to put a flywheel weight on. I feel like the counter balancer is already a huge flywheel weight...
I'm a little surprised you felt the need to put a flywheel weight on. I feel like the counter balancer is already a huge flywheel weight on these engines and it bugs the crap out of me! No instant snap at the crack of the throttle.! Kind of a brrrrooooomm instead of a quick Braaapppp!
Then again I lighten the flywheel on my Yz 250s to make them feel more like an RM,so maybe I'm the weird one.
AJ565 wrote:
You're not jetted right if your bike does that. Mine is instant and friends that ride it hate it because they are used to theirs not...
You're not jetted right if your bike does that. Mine is instant and friends that ride it hate it because they are used to theirs not being jetted right (they don't feel like ordering the parts to do it).
It's not jetting. I have it carbureted perfect. Its more rotating weight being slower to turn over at the snap of the throttle. I notice it big time.
seth505
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seth505 3/22/2019 10:48am
3/22/2019 10:48am
Just my opinion but I'd ditch the flywheel weight and just play with the powervalve spring settings.
AJ565
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AJ565 3/23/2019 8:31am
3/23/2019 8:31am
JWACK wrote:
I'm a little surprised you felt the need to put a flywheel weight on. I feel like the counter balancer is already a huge flywheel weight...
I'm a little surprised you felt the need to put a flywheel weight on. I feel like the counter balancer is already a huge flywheel weight on these engines and it bugs the crap out of me! No instant snap at the crack of the throttle.! Kind of a brrrrooooomm instead of a quick Braaapppp!
Then again I lighten the flywheel on my Yz 250s to make them feel more like an RM,so maybe I'm the weird one.
AJ565 wrote:
You're not jetted right if your bike does that. Mine is instant and friends that ride it hate it because they are used to theirs not...
You're not jetted right if your bike does that. Mine is instant and friends that ride it hate it because they are used to theirs not being jetted right (they don't feel like ordering the parts to do it).
JWACK wrote:
It's not jetting. I have it carbureted perfect. Its more rotating weight being slower to turn over at the snap of the throttle. I notice it...
It's not jetting. I have it carbureted perfect. Its more rotating weight being slower to turn over at the snap of the throttle. I notice it big time.
Something is off then, I have the same bike and it’s instant throttle response with a lot of snap out of turns.
JWACK
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JWACK 3/23/2019 9:05am
3/23/2019 9:05am
AJ565 wrote:
You're not jetted right if your bike does that. Mine is instant and friends that ride it hate it because they are used to theirs not...
You're not jetted right if your bike does that. Mine is instant and friends that ride it hate it because they are used to theirs not being jetted right (they don't feel like ordering the parts to do it).
JWACK wrote:
It's not jetting. I have it carbureted perfect. Its more rotating weight being slower to turn over at the snap of the throttle. I notice it...
It's not jetting. I have it carbureted perfect. Its more rotating weight being slower to turn over at the snap of the throttle. I notice it big time.
AJ565 wrote:
Something is off then, I have the same bike and it’s instant throttle response with a lot of snap out of turns.
17-19 ktm 250s feels like an Rm with a massive flywheel weight. I say this because I own an Rm and really enjoy how they respond. They are very quick to turn over at low RPM.
As for my 250sx. It's working how it was designed and nothing is wrong with it. It's really awesome and I like it but, it's a kinder, gentler 2 stroke IMO.
If I were the op and wanted it to be even smother I would consider a 300 kit and maybe a tooth less on the rear.
AJ565
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AJ565 3/23/2019 3:02pm
3/23/2019 3:02pm
JWACK wrote:
It's not jetting. I have it carbureted perfect. Its more rotating weight being slower to turn over at the snap of the throttle. I notice it...
It's not jetting. I have it carbureted perfect. Its more rotating weight being slower to turn over at the snap of the throttle. I notice it big time.
AJ565 wrote:
Something is off then, I have the same bike and it’s instant throttle response with a lot of snap out of turns.
JWACK wrote:
17-19 ktm 250s feels like an Rm with a massive flywheel weight. I say this because I own an Rm and really enjoy how they respond...
17-19 ktm 250s feels like an Rm with a massive flywheel weight. I say this because I own an Rm and really enjoy how they respond. They are very quick to turn over at low RPM.
As for my 250sx. It's working how it was designed and nothing is wrong with it. It's really awesome and I like it but, it's a kinder, gentler 2 stroke IMO.
If I were the op and wanted it to be even smother I would consider a 300 kit and maybe a tooth less on the rear.
That’s what I’m trying to tell you, these engines rev faster than an RM I’ve ever ridden and in no way is it kind or gentle when tuned correctly. It’s explosive lol
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