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Aftermarket upgrades for 2003 Summit 800HO?

I have a 2003 summit 800HO 151" that is an absolute dog on the bottom end. It has very low miles and is in great shape. It has a hesitation on the bottom end and really needs to be woken up somehow. It already has a can and run nothing but amsoil and high octane fuel. I am thinking about boyesen rage cage but what else can i do?
 
sound to me like you need to have your carbs cleaned really good, start with that. Then you need to check your compression, if that is low you may need new rings, lots of 800s in them early years have problems with rings and may be low on compression, start there.
 
I think you need to look in to it a little more before throwing parts at this thing that might not fix anything IMO. Might wind up throwing a bunch of parts at it only to have the same problem. How many miles? Have the clutches been serviced? Hows the belt look? Lots of things to look at to make sure it is up to par.
 
Brand new belt, 1300 miles. I havent touched the clutches but the guy i bought it from stored it in his heated shop after every ride and would change out the crank case oil every year and grease it every ride. It has been meticulously cared for. Very good compression on both cylinders
 
Here's what I did to my '03 Summit: Drop one size on mains, go up one size on pilots (to 20's), adjust fuel screw out 2 turns (from all the way in), add Boyesen reeds. Thing woke RIGHT up on the bottom end (and yes, they are dogs until you get the reeds). Also, since you have a can, just use stock main jets first until you can run a WOT plug chop on a cold day.

Have FUN!

G MAN
 
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There were many 2003 800 summits that come from factory with the black 160/300 secondary spring. Especially Euro models, they all had that black spring, I have no idea why, what a damn dog.
Pull the secondary apart and see which secondary spring is installed.
If the black is installed, remove it and get a purple secondary spring from any 04~newer 800 summit rev or xp sled and install it.
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check the secondary spring
get the stock skidoo drive belt on there
good belt deflection as mentioned here
...that should give you a good push off the dock to start to recalibrate if needed.
 
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on my 03 zx 800 HO Highmark Extreme with stock 159 I went down 2 jet sizes on main jet and dropped the needles one spot and put two SLP flo-rite filters in the dash. Stock pipe with HPS can. Didnt mess with any of the DPM stuff or any of the stock primary stuff but i often play with the RPM adjustmenter bolts on the primary depending on snow conditions. Secondary is Team LW 04 with (i think) 42 degree straight helix.....cant remember for sure.....also cant remember exact secondary spring specs but I know it was stiffer specs than stock. If I recall the stock secondary was the ancient button style.

I think the biggest thing i did to wake it up was gear it down big time.....i also forget the exact ratio i am at now. Right now i am real satisfied with how it runs.

If i wanted to wake it up any more on low end I would look to tune the primary for slightly higher engagement RPM and probably do it with a spring change.

Good luck.
 
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