Yes you heard that right. After a full engine rebuild on my 2004 KDX200 the power delivery is way off. Power Is very flat at low and mid rpms, even mid high rpms. But if you really let it scream, the power suddenly goes up 300%. Why do you think it's doing this? What are the most likely 5-10 issues to check first in your opinion?
Here is a list of things that changed since it last ran well:
All seals have been replaced
New crank and main bearings
New piston and rings
New Boysen Power Reeds
Stator plate moved about a millimeter CCW (an effort to gain top end power)
Clean air filter
Gas used was 4 month old premixed filled to top in plastic container...its all I had at the time!
Let me know thoughts, thanks!
Flat down low, flat mid, but Rocket at high revs?
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- SS109
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Re: Flat down low, flat mid, but Rocket at high revs?
Check that your powervalve is operating correctly.
Youtube Channel: WildAzzRacing
AZ State Parks & Trails OHV Ambassador - Trail Riders of Southern AZ
Current KDX: '98 KDX220
Old KDX: '90 KDX200 -White/Blue
'11 GasGas EC250R
AZ State Parks & Trails OHV Ambassador - Trail Riders of Southern AZ
Current KDX: '98 KDX220
Old KDX: '90 KDX200 -White/Blue
'11 GasGas EC250R
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Re: Flat down low, flat mid, but Rocket at high revs?
SS109:
What is the best way to go about this?
What is the best way to go about this?
- Molly's 70
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Re: Flat down low, flat mid, but Rocket at high revs?
If you lend someone $20, and never see that person again, it was probably worth it.
- SS109
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Re: Flat down low, flat mid, but Rocket at high revs?
How I would start is to do like in the video above. The gear should move at a certain rpm consistently. If that checks out good. You can then pull your exhaust pipe and operate your powervalve by hand making sure the center and both subvalves fully close and open.
Youtube Channel: WildAzzRacing
AZ State Parks & Trails OHV Ambassador - Trail Riders of Southern AZ
Current KDX: '98 KDX220
Old KDX: '90 KDX200 -White/Blue
'11 GasGas EC250R
AZ State Parks & Trails OHV Ambassador - Trail Riders of Southern AZ
Current KDX: '98 KDX220
Old KDX: '90 KDX200 -White/Blue
'11 GasGas EC250R
- Slick_Nick
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