My freind sent his jugs to get ported at psi ,we have it together it is running rich in the mid range ,it cleans up at wot ,we dropped the needles all the way down ,still no luck , put in thicker needles from 600 same thing but cleaned up some, don't think its carbs ,should be going fatter with porting , thought it might be clutching, but its loading up even before engagement . stator ? usually on high rpm ? all 3 holes wet , changed plugs 3 times , going to check fuel pump diaphram tonight , any thoughts ? What is weird is another freind sent his 600 twin jugs at the same time and is having a simular problem , I haven't seen it yet .

Changed all electrics with good known parts this thing is still running rich, 150lbs compression, fuel pump good ,float hgt good, if I lean this thing out and my mystery problem disappears this thing will burndown , what have I missed , gas is good , Is it possible port job is bad ? Any ideas would be appreciated .

Try psi for any answers.Also you said that it loads up b-4 engagement ,what about the pilots,and in some cases a ported motor gives you more efficiency.Was the sled running ok b-4 the porting?

Yes sled ran before porting , psi recommends going up two jet sizes richer !

Here's a jetting chart out of AAEN'S carb tuning book. It's for the TMX series. shane

maybe you need to lean down the nozzle's 1or 2 size'sand richen your main's up

we worked on it till 2am , mains up 2 sizes , mains down 2sizes , larger taper needles , timing , going to get different trigger only part we haven't changed , I don't think thats the problem BWTF . Wish I had a set of jugs laying around to prove out bad port job at this point .thanks for reply ! We are outta here this weekend to get some sled time hope your doing the same.

I had a very similar problem with a 97 ultra 680. I bought this fall and rode it for 98 miles and blew a rod through the case. Rebuilt it and the same problem exists, the PTO side cylinder keeps loading up until I hit about 50 mph and it cleans out and takes off. By that time its scary fast. It has SLP pipes and the cylinders were ported when I bought it. I've tried everything to fix it and its still a mystery. replaced stator, cdi box, coils, reeds, bottom end rebuild, and tried many different jets. help

If we come up with a fix I'll let you know .

i have a 2000 700 xc and i seem to have the same problem when i first start my sled after it warms up the problem seems to go away sometimes i have to shut it off for 10 mins after its warmed up when i start up after the 10mins it's good its strange i know but my sled has always been that way

We have it running and dialed in , We had to get a set of pipes , stock pipes didn,t cut it . the engine is over ported for running trails , the power band is very narrow and the engine is a picky ##### needing constant jetting and clutching adjustment . When the jugs were sent in his porting request was for trail/lake porting , well it's a great lake runner but temp. changes require jet changes on the trail . My buddy needs to get tempa-flo .

I have built many XCR based trail motors as well as race motors. I really doubt its overported for trail. The difference in most race engines and trail porting is the head design and compression. Have you checked your squish clearance? What pipes did you have to go to to make it run better? What is your ignition timing set at? What air box are you using? Was the crankcase ported also or just the cylinders? I would be glad to help you out, we are located In Northern Indiana 260-637-7953

are you positive its rich?

You need smaller needle jets and lighter flyweights. I had a '93 750 storm ported with oem pipes,i went from R-O nj to Q-4 nj, clips at #3 and clutching went from 10-64 with blue spr. in pr. & 36° helix to #15 weight(55gr) with red/white spr. in pr. & 46-34 helix. Stock gearing. stock rpm was 7800, ported 8100-8250.