WR450 bog w/ low rpm throttle whack
Posted June 28, 2005 - 06:29 PM
Needle from OBEKP #5 to JD Red #5
Main Jet from 145 to 165
Pilot Jet unchanged, 45
Pilot Air Jet unchanged, 70
Starter Jet unchanged, 65
Leak Jet from 70 to 52
fuel screw from 1.5 to 1.75 turns out
Exhaust - from uncorked stock to YZ
Before, it had a slight WOT miss. Now it totally hammers, except if I'm cruising at low RPM in 2nd or 3rd gear and then just whack the throttle open. Unless I kick it down it'll bog for a second or two before catching up and hammering again. I'm having a hard time keeping the front wheel down in all other circumstances, I'm really happy with the changes. I'm at sea level and it's about 85 degrees and humid tonight. Should I go back to the #70 leak jet or is it an AP issue. I believe the delay is still at the stock setting, but I don't think the pump squirt isn't hitting the slide.
Someone please help.
Posted June 29, 2005 - 04:10 AM
"The other part that is often ignored is the adjustment screw that comes on the linkage stock. This is to set the starting point of the accelerator pump. Turning it in delays the start and turning it out advances the pump action to start earlier. At immediate squirt from idle would be zero delay from the "touch point", where the rod just touches the diaphragm. A setting of 1/2 - 1 turn inwards delays it adequately to keep from squirting on the slide. This, I believe, was the .6mm measurement with feeler gauge. The original BK Mod posting from SUnruh also had the pump stroke set to 1 1/4 turns out from touch point to set the flow. This did not say the pitch of the screw being used and so was a little vague."
Posted June 29, 2005 - 05:12 PM
I tried the 48 pilot and the 40 leak jet. The bog got worse. I turned the AP delay 1 full turn in, in 1/4 turn increments, but the bog is still there. I think the 45 pilot may work better because I was getting good idle at 1 turn out or less on the fuel screw, whereas yesterday it was at 1.75 turns out. The bog was never there with the #70 leak jet, but it also didn't have the YZ exhaust, JD needle or main jetting it has now. I also changed from a 65 starter jet to a 70 because I was having a bit of a hard time starting with the E-start, but that shouldn't affect this, should it?
Posted June 29, 2005 - 07:56 PM
Posted June 29, 2005 - 08:01 PM
Posted June 30, 2005 - 10:33 AM
Yep your bike hauls booty When we riding again?
The best thing Ive seen on the 05 WR4.5 is the boysen pump cover and a change of the main and pilot. After seeing how well Endurordr's bike worked I pulled one off the shelf and tried it on the shop bike. All I can say is WOW.
Not gonna say how it works on the 03 ro 04 as the engine dynamics are slightly different. Those bikes accept the 40leak jet well, with a tweak on the APscrew.
Posted June 30, 2005 - 11:33 AM
Posted June 30, 2005 - 01:45 PM
Anyway, where is the fuel screw adjustment at? the response of the fuel screw will give you an indication as to whether your in the right spot on your pilot circuit.
Posted June 30, 2005 - 03:04 PM
Posted June 30, 2005 - 03:11 PM
Posted June 30, 2005 - 05:40 PM
Posted July 01, 2005 - 11:22 AM
Posted July 01, 2005 - 07:16 PM