kitecop917
Cadet
- Joined
- Apr 2, 2015
- Messages
- 13
What would cause an RPM drop at high RPM on a 2 stroke carbed 2003 200XL SWB? Once i hit 5k with a 21p prop or 6200ish with a 19p i get sudden RPM drop.
Fuel issue has been ruled out completely. I have replaced all fuel lines, anti-siphon valves and filters. The tank vent is not clogged, carbs are clean and all feeding fuel evenly at WOT. I am also only getting 32mph with a 19P prop at 6000rpms.
Did some diagnosis today. here is a list of what i did.
-observed carbs with air box off- even and normal fuel flow at WOT.
-ran with gas cap off- no noticeable changes
-ran on an aux tank- no difference
- replaced spark plugs one at a time and did a test run between each change- no changes
- cleaned grounds that are attached to the power pack plate- no change
- did compression check- all cylinders are 120psi or just over
-observed ride plate while at speed. its completely submerged so i will have to raise motor a good 2-3"
Im thinking the motor height is what is creating so much slip and lack of speed but the bogging has got to be an electrical issue. I think my next step is testing power packs... something is failing under load.
Fuel issue has been ruled out completely. I have replaced all fuel lines, anti-siphon valves and filters. The tank vent is not clogged, carbs are clean and all feeding fuel evenly at WOT. I am also only getting 32mph with a 19P prop at 6000rpms.
Did some diagnosis today. here is a list of what i did.
-observed carbs with air box off- even and normal fuel flow at WOT.
-ran with gas cap off- no noticeable changes
-ran on an aux tank- no difference
- replaced spark plugs one at a time and did a test run between each change- no changes
- cleaned grounds that are attached to the power pack plate- no change
- did compression check- all cylinders are 120psi or just over
-observed ride plate while at speed. its completely submerged so i will have to raise motor a good 2-3"
Im thinking the motor height is what is creating so much slip and lack of speed but the bogging has got to be an electrical issue. I think my next step is testing power packs... something is failing under load.
