deaner
Active VIP Member
Small world. This is Dean Bala. I done some hunting with your dad. Pretty interesting trip. haha.
My engine is out getting rebuilt right now too. Should hook up for a ride when we get our sleds going again.
2009 800 air box mods
- Thread starter DOAKLEY16
- Start date
Small world. This is Dean Bala. I done some hunting with your dad. Pretty interesting trip. haha.
My engine is out getting rebuilt right now too. Should hook up for a ride when we get our sleds going again.
- Thread starter
- #22
deaner
Active VIP Member
Nothing. Just way too many miles. Crank runout got way way out of spec and it was making me nervous. My own fault though. Should have checked it this summer. Ill drop you a PM when I get her back together.
NWPOWDERBUM
New member
I'm thinking of Modding my lower or upper airbox but still deciding. I bought the sled used with 540 jets and. 030 shims and its running rich, so I want to add some air to lean out a bit. I also have an slp pipe, can and head. I'm not sure how the air sensor will be affected from using an upper vent vs the lower box vent. What's the best option for me to lean out and get it better set up? Also how are you guys gauging lean/rich adjustments?
NWPOWDERBUM
New member
The 500 is the next size down for mains from 540, what are you using for needle shims? What elevation do you ride at,air temps, fuel types? All those factor in to the equation. What did u notice for richness and jetting when you went with the upper vent vs the lower? The whole idea of me venting is not only for powder bog but to lean out WITHOUT rejetting. I can fine tune it later if needed.
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I ride Golden and Revelstoke mostly, up to 8000 ft, give or take. Stage around 1200ft at times. No needle shims, keep an eye on EGT's in mid range and noticed they can run up there. Will add a 20 thousand shim when I get more mobile. Always premium fuel, usually Shell 91. Temps vary of course. Did upper and lower airbox mods at the same time, so cannot comment on the difference. Have never had a bog issue with my sled, but it does draw air from three locations. Good throttle response. Haven't checked the wash yet this season, but the plugs are a dark brown. Right now, I'm ok with this, as I only have a couple hundred miles on the BB and prefer it rich for the time being.
NWPOWDERBUM
New member
Thanks, thats good info! I just changed out my plugs from an ecs-5 to the ecs as well (larger gap), so I'll do one thing at a time to dial everything in. We're probably close on jetting since my altitudes aren't nearly as high, but I'll probably take it out and run some plug testing then modify the box accordingly if needed. Probably put in some flow rite rubber inserts in the lower box, maybe add one to the upper as well. I don't run an egt gauge but I don't think its a must for me at the moment.
what temps do you look for when riding on the trail up, I try not to let it past 1150, is that to high for the lean spot at 6-7 rpm.
I have my egt alarm set at 1200 F. I think you are ok with 1150, mine runs there on the trail all the time. I have to blip the throttle to keep it below 1150. My season is done, but will be shimming the needle or putting an '07 adjustable needle in for next season.
Has anyone tried the timbersled kit on the xp. I'm generally a fan of using the lower air box, but if stock is that restrictive, it may be a good alternative. Not to mention maybe losing a few lbs from the bulky stock airboxes?
Mine will keep climbing in temps, im jetted down to 450's, needle is a 07 needle and the clip is in the 3 spot with my rkt 860 rk porting and and rk y pipe. Ive been reading a bit and now i cant remeber if i tossed the shim that was in there and i im thinking that the needle is in there with just the clip. I could probably move the needle and try get the temps down abit in the mids. i had a couple other problems last week with mine it seemed to have a gurgle when idleing around just above 5k rpms but as soon as i was on the throttle it cleared up, and then on sunday it had a bad snow bog for the first time and i could not keep my vents clean for it to get air.
treeboy
Active VIP Member
Duch do you have etg's? If so what temps you hitting in mid and full out. It does sound like you need to Jet up, those jets you got in there you must be running pretty lean. How's the plugs?
Plugs are golden brown and actually are a little wet looking, WOT in a good long pull its between 1050 and 1150 f on EGTS, running 14:1 domes and 25 % race fuel, ecm is programmed by rk as well and thermo is deleted, 6-7 k rpm on trail the temps sneak up towards 1200 and will go higher if i dont pay attention, but i blurp the throttle or pin it and it goes back down to 1100 's, riding in the trees it stays cool under 1000 f. At 5 k rpms i notice a bit of a gurgle like too much fuel but it never misses when im on the throttle, and i cant remember if it always did that or not. I was running 460's before the 860 kit went in, just with the head and nitrous.
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treeboy
Active VIP Member
With those reading duch your mains sound like your in the perfect safe zone, if you hitting over 1250 or past 1300 in the mid might want to try shimming the needles
pfi572
Active VIP Member
My RKT a few years ago i had to run 480 mains as 450's tightened up. This was a 2009 RKT 860. A few others all blue theres up also running lower jetting. (Mid range problem)
My set up then;
14.1 head with 20% 110
Dyno port y and low elevation pipe
Boyeson reeds
2007 needles raised one clip from middle. (Clip lowered)
17.5 pilots
RKT Programmed ecm
Timber sled intake
My set up then;
14.1 head with 20% 110
Dyno port y and low elevation pipe
Boyeson reeds
2007 needles raised one clip from middle. (Clip lowered)
17.5 pilots
RKT Programmed ecm
Timber sled intake
Running that intake may be the culprit
pfi572
Active VIP Member
Nope i ran it with stock intake with rear holes first so i wasn't chasing gremlins. Changed to other after i had been running it for sometime.
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