08 XP jets with flow rites in air box

[Duct tape Doo]

I have a stock 800 XP with a 13.5:1 Terra Alps head, and Y pipe, BMP can and a 2" flow right on the pto side and a 2.5" flow rites on the mag side, I was advised to fatten from the stock 480 jets to 500, It runs crisp enough at colder temps at 3000 ft but feels a bit fat on a warm day at 3000 ft, I am not planning on adding pyros as i have on my other sleds and the spark plugs look ok, A piston wash look is tough to do on an xp so i am wondering what kind of mains others are running with flow rites added to the air box.
I am using about 3 gallons of L100 per tank so i am probably ok to put in 490 jets.

 

[flabbajabba]

What kind of comp. are you getting with your head my buddy has a Terra alps head 13.5 to 1 and he's at 175lbs(EDM). We bumped up the mains and shimmed the needles to what ever Ted said to. I'll try to find the specs. Same as you I miss the days you could just look down the spark plug holes and check piston wash.

 

[bayman]

I have a very similar set up, and found it to be rich with the 500s. Put the 490s in for the last two rides and the plugs are just a touch darker than cardboard. Would take a picture of plugs but the boxer ate my camera, gotta buy a new one for this weekend. Anyone wanna buy an unspad 2 year old boxer?:d

 

[Duct tape Doo]

Ted said to run a .020 shim but our doo dealer only had 0.30 so i decided to stay with stock needle height and just stay out of the mids.
I had the clutch weighted fine at 3000 ft and - 18 C before the air box mods but had to add weight to 16.9 grams on clicker 3 so i know the flow rites make power when the air is good, I really don't want to rejet down from 500's on the mountain if i can help it.

 

[shoppingcart111]

Why different size flowrites?

 

[Duct tape Doo]

Terra Alps sells a package of head, Y pipe and flow rites, The mag side is larger because there is less air flow from the holes and foam pre filter than the pto side that sucks air both through the side panel holes as well as under the triangle side panel that is a loose fit against the tunnel and seat.
I would not have believed that the flow rites would cause the RPM and clicker settings to change that much in the cold prairie air but i added fly weight twice to try and keep my clickers at 3 or 4 to acheive 8150 rpm on analog tach, this was with DJ ramps as well which should have fixed some of the 08 (213 ramps) tendancies, This is why i think i need to go down to 480 or 490 mains as the Terra Alps head plus the full DJ kit pulled very hard with dense air at 3000 ft.

 

[treeboy]

I got a very close set up on mine. With all the extra air coming in when I had stock jetting (480 I think they are) still in and needle seting my egt's would easy be 1300 plus once it got up to 1650. Super lean in the mid range.
Now with 500's in and .20 shims I havent seen any hotter than 1300. Still I can hold the mid range longer, but I would'nt hold it there all day.

 

[bayman]

I got a very close set up on mine. With all the extra air coming in when I had stock jetting (480 I think they are) still in and needle seting my egt's would easy be 1300 plus once it got up to 1650. Super lean in the mid range.
Now with 500's in and .20 shims I havent seen any hotter than 1300. Still I can hold the mid range longer, but I would'nt hold it there all day.

With that set up(500's and shim,'09), I was real rich, plugs were almost black. Changed to 490's with shim and plugs were still dark. Took shim out and ran 490's and plugs are nice and light brown. Hard to check the piston wash on these friggin' things.

 

[Stonehands]

I have an 860 so maybe a little different. 500 mains 07 needles shimmed. Egts 1150 WOT at 3k to 6k plugs and wash just right. Also have a wideband o2 which reads 13 to 13.2/1 a/f which according to dyno numbers is the best a/f for power on the 800r. Could stand to shim a little more in the mids according to a/f as it can get up to 15/1 which is a bit lean. If I only had egts I might want to trim a little fuel in the mains but wash a/f and plugs say otherwise. A/f is a great tool for tuning idle, midrange, and wot. It has helped me tune my carbs perfectly.

 

[OVERKILL 19]

I have an 860 so maybe a little different. 500 mains 07 needles shimmed. Egts 1150 WOT at 3k to 6k plugs and wash just right. Also have a wideband o2 which reads 13 to 13.2/1 a/f which according to dyno numbers is the best a/f for power on the 800r. Could stand to shim a little more in the mids according to a/f as it can get up to 15/1 which is a bit lean. If I only had egts I might want to trim a little fuel in the mains but wash a/f and plugs say otherwise. A/f is a great tool for tuning idle, midrange, and wot. It has helped me tune my carbs perfectly.

Where did you mount your a/f senser? Just curious!

 

[Stonehands]

Where did you mount your a/f senser? Just curious!

End of the pipe just before the can. Top of the pipe of course.