09 300 missing some mid range power

anyone have jetting or setup tips to get better mid range out for a 09 300 xcw?

it has good low range but when half or wide open throttle it seems slow. took out my buds 250 xcw on the same loop and i had to let off the throttle in areas i had to hold mine wide open.

i just went to a 152 main from a 158, shop said it was too rich up top. this helped things but is still missing something. i would think holding a 300 wide open would want to throw you right of the back, the 250 seemed to hit the powerband with more power.

when i bought it new it seemed to have plenty of power. now not so much. even lifting the front end in rocky technical areas seems lagging now.

stock gearing, 50r 14(?)fr.

AS is 1.25 out (i tried 2 out and 1.5 out)

mj is 152

p is 35

3rd clip

yellow pv spring(liked red but it just made it hit harder down low)

fmf tc 2 muffler, stock up front.

If it ran good at one time, and now you're experiencing a loss of power, you need to figure out what is different. Has the weather changed and your jetting needs to change with it? Is your compression down?

Try playing with the needle and pilot jet. Try putting a 51 or 52 tooth rear sprocket on. Try playing with the power valve. Is your ignition map on the "hot" setting?

i did notice the 250 had a 51 and im running 50. would the one tooth make that big a diff?

the weather is about the same, same time of year as when i picked it up last year. temps are around 50 also.

i was thinking of bringing it in for compression check also, is there an at home method or tool out there? i know with cars they have a guage you thread in and turn over the engine. is there one specific for motos?

ignition is on aggressive, or connected. PV is clean. i did put in the red but it didnt seem to help alot in the mid range. definately hit harder in the low range.

post this here in the rocky mtn regional area


and ask locals what their jetting is on that bike in colorado at your altitude. seems like the pilot jet is small ( most 09 300's go with 38 ) but i dont know about the elevation. use the optional N2ZW needle too for more low to mid hit.


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