Rubbermount_EVO keihn setup at Altitude

[Tomcatt]

Originally Posted by Roaddawgie

IMS -3
WOT seemed good
popping / Farting redused 90% popping etc. occurred when coming to a stop w/ speed at 30mph or less....
Better acceleration from a dead stop but still a bit sluggish
Haven't pulled plugs yet (will do that tomorrow)
will also run the same 13 mile loop with IMS @-4

I am wondering what created this improvement ? was it rerounting the oil mist or was it the IMS adjustment????

Im Headed in the right direction.........I think.

Most likely you're seeing an improvement with a richer mixture. Did the idle change at all?

You'll know more after a ride with the IMS at 4 turns and I'll explain more. Not trying to be a jerk, just wanting to keep this as "blind" a test as possible.

[Roaddawgie]

The idle Was good about the same as -2. I think accelerated better out of the hole but still not where it should be imo. I'm hopefully getting a new air filter as the old one needs some help (waiting on usps as the moco doesn't seem to stock parts for an 05 , guess they want me to buy an electric bike for 30k!!!!!
So most parts are courtesy of j&p......

thanks for monitoring "project 883"

[Roaddawgie]

Originally Posted by Tomcatt

Most likely you're seeing an improvement with a richer mixture. Did the idle change at all?

You'll know more after a ride with the IMS at 4 turns and I'll explain more. Not trying to be a jerk, just wanting to keep this as "blind" a test as possible.

Ok Rode today:

2005 XL88sL Hi flow AF w/ Vance and Hine short shots

IMS -4
37 degrees
13 miles
top speed 60

Idled well after warme up

WOT good acceleration

much less popping / farting than w/ IMS @ -3

main pops / farts occurred @40 mph or when I needed to down shift
The pops etc. were much fewer in number and only in the 40mph area on deceleration going into stops.

Accelleration out of a dead stop was better, I think it still could be a little more efficient, ( my frame of reference is a bit skewed due to big twin super e and Mikunis w/cams in them). So I hope my expectation is not too high.

Where should I go from here? Based on this should I be going to a larger Pilot Jet and turning the IMS in to -2 or 2.5?

All input is greatly appreciated

[Tomcatt]

Originally Posted by Roaddawgie

Where should I go from here? Based on this should I be going to a larger Pilot Jet and turning the IMS in to -2 or 2.5?

Put in a 45 pilot jet. Make sure it's a real Keihin jet.

Run your test again, 45 pilot jet, with the IMS out 3 turns, then again at 4 turns.

Just replace the pilot jet, don't change anything else so we're just seeing the effect of the jet change.

As you changed the IMS setting from 2 to 3 to 4 turns (with the 42 pilot jet) did you notice any change in your idle? Idle speed or smoothness?

[wedge]

I agree with changing only one thing at a time.

I would adjust it every time by using the idle drop method rather than randomly playing with 2, 3, and 4 turns. 4 turns is close to or at the point where pressure is not strong enough on the spring and the setting can vibrate back out as you ride.

As you go larger with the pilot jet, yes, the mixture adjustment at idle will require less turns. It's not exactly linear because it all depends on how much the transfer ports are affecting the idle. Using the idle drop method will always get the idle where it belongs, then the difference in the pilot jet will show up in how the transfer feels. If you are over three turns out on the mix, then that's a good sign you need to go larger on the pilot.

As always with idle drop tuning, you need to set the idle speed screw low as possible and once you find the sweet spot for adjustment, try lowering the speed and adjusting again. Once mix is tuned right you can bring the idle up to where it needs to be. Lower idle speed allows you to hear the drops better.

[Roaddawgie]

Originally Posted by Tomcatt

Put in a 45 pilot jet. Make sure it's a reabl Keihin jet.

Run your test again, 45 pilot jet, with the IMS out 3 turns, then again at 4 turns.

Just replace the pilot jet, don't change anything else so we're just seeing the effect of the jet change.

As you changed the IMS setting from 2 to 3 to 4 turns (with the 42 pilot jet) did you notice any change in your idle? Idle speed or smoothness?

Ok I changed the air filter to a SE k&n. Breather routed outside the carb Took her out 13 miles 43 degrees top speed 60 wot good IMS -4 . Idle well .1 carb fart. Acceleration out of the hole was the best yet. It appears this improvement was related to air delivery to the carb.

As wedge noted the idle drop with the new air cleaner and breather routing might be the ticket

[Tomcatt]

Originally Posted by Roaddawgie

Ok I changed the air filter to a SE k&n. Breather routed outside the carb Took her out 13 miles 43 degrees top speed 60 wot good IMS -4 . Idle well .1 carb fart. Acceleration out of the hole was the best yet. It appears this improvement was related to air delivery to the carb.

42 or 45 pilot jet?

[Roaddawgie]

Originally Posted by Tomcatt

42 or 45 pilot jet?

Oh sorry I reran w the 42 jet I will change to 45 and re test

[Tomcatt]

Originally Posted by Roaddawgie

Oh sorry I reran w the 42 jet I will change to 45 and re test

Sounds good. Try 3 turns and 4 turns on the IMS. Change nothing but the pilot jet and the IMS turns. Pay attention to how it idles. In a bassackwards way you're doing an idle drop test by doing these tests.