Ride report. I did 74 miles in the high dez yeareday. Bike ran noticeably better, has a good bit more bottom and it is a rocket. As I said before my bike is well sorted, ran very good before and was very happy with it. Now it is simply flawless. I mean it runs absolutely PERFECT. It really is unbelievable. When I say flawless I mean it. Idles perfect, is very snappy, not one hiccup, dead throttle or popping, bogging nothing. Just instant and perfect modulation every single time you hit it. I would have to say this is now the best running bike of any kind I have ever tossed my leg over. Simply flawless how it runs, has huge power, is EZ to control. My buddy with a very good running KTM 350 rode it. His remark on the motor was "beautiful" which is a funny word to describe it but he is right. The kicker for me was he rode it about a mile, said he wanted his bike back and I figured it was to big or there was something he did not like about it. I said "don't like it?" he said... "If I ride this bike any more I'm going to hate my bike". Said the motor was flawless and crazy fast and the ZipTy suspension was out of this world. We nicknamed it the starship enterprise as it just blasted everything. I explained what I had done on the way there and hoped everything was OK for the ride. He said he knew immediately everything was OK as I was exploding every corner exit and was disappearing into the horizon at an alarming speed. The more I rode the bike the more I realized how good it was and how I had been compensating to some extent to ride around it's small flaws. This compensation became less and less as I realized this simple mod eliminated anything I was compensating for. The now absolutely perfect motor, super smooth MWEE clutch lever and amazing ZipTy suspension put me in that zone we all love to find and I could do no wrong. I was hauling ass and it was very EZ. As you can tell I am elated at all this.
Let me back up a little.
As I said my bike ran very good before. I was servicing the air filter and thought to myself, it would not take a lot more digging to get that butterfly out and gave it a go. So I did. When I first started it afterwards I was a little spooked it would be fine. Started right up and ran nice. Rode it around the block and it did feel better but on pavement everything feels faster (hook up) and smoother. My house is at about 75 feet elevation. When we got to the dez staging area which is about 3500 feet and was about 25 degrees colder and I tried to start it it turned over about 5 rotations and nothing. I was like "oops, glad I brought the butterfly with me". Touched the button again and it fired right off and idled nice. Not sure what that was about but was not a big deal and my bike has done this cold before. OK, go for a ride and immediately notice, just like other described, it has more snap and pull right off idle and into the first 1/4 turn of the throttle. Was thinking to myself "is this real or am I imagining it because i read that"? The more I rode the more it was very obvious it is running a good bit better and pulls really hard in that first 1/4 throttle. Then I start to notice it seems to not like huge throttle openings in the mid range where before it did not seem to mind that. I was thinking to myself, this is where the butterfly does its magic. It was EZ to reprogram my wrist to not do that and I was rewarded with a great running bike. Then I thought I would play with my JD tuner some. I left the bottom (green) alone as the bottom end was freaking PERFECT. I leaned out the mid (yellow) 2 clicks and richened the top 2 clicks as it seemed like it ran out of breath slightly. Bingo. Mid range was now 100% back and better than ever, top end gained some pull. I did not touch a thing after that because it literally runs perfect. Not perfect for EFI or carb or whatever but simply flawless and perfect everywhere. So feeling all frisky and gaining more and more confidence with every corner I exploded and rock garden I blasted through I started trying to make it stumble or fart. I was going up loose technical foot deep shale hills that can be the bain of a lean or finicky EFI system and purposely going a gear or two high and letting the RPMs drop dangerously low, holding on for the cough and spit me over the bars. The bike simply chugged up it flawlessly and I felt there was almost no way to stall it. It has an old school carbureted big flywheel unstallable feel to it down low now. I did everything i could to induce a stall or, fart or pop or something and it just kept running flawlessly. I'm seriously in shock. I wheelied up on pretty nasty hill and sat at the top while my buddy on the KTM 350 struggled and crashed.
As you can tell I am giddy about all this. My bike runs absolutely flawless. Has that super forgiving carburator like feel on the bottom but with more snap and simply pulls hard everywhere. Even though all I did to mine was remove the butterfly it seems to come back to idle a lot smoother and perfectly. Again, flawless. It has gained a very noticeable amount of snap and pull in the first 1/4 throttle, has more in the middle and after my JD tweak more on top. I'd say a 15% gain bottom, 10% mid and 10% top. Honestly I was not expecting a lot from this, figured if there were gains it would be small and maybe hard to detect. I have to say I am blown away. Put me in a groove where i could do no wrong. This is semi open dez but has a lot of variety. It had rained some and so we had power robbing deep wet silt. My bike would rip huge 4th and 5th gear 50 mph wheelies though deep whoop fields like nothing. Comes out of loamy deep corners blowing up berms and the front wheel reaching skyward and then jump and wheelie long rows of deep whoops like I knew what I was doing. I felt faster than ever and Travis who I ride with alot said I was absolutely flying. He said he could stay with me for about three corners and then i just faded away into the horizon like I was on a missile. As you can see I couldn't be more happy with this simple mod.
Disclaimer. I'm not saying you will see the same results but for me on my bike it was transformational which is odd because the bike seemed pretty freaking good before. I am not recommending it as it will for sure void any and all warranties and you are messing with a factory EFI system with components you could ruin costing money. What I am saying though is if you don't care about any of that and are the type of person that likes to try stuff and work on things this mod, at least for me, is the real deal. My bike no longer feels like a good runing 450 but now feels like a real 511 firebreathing beast. It has lost none of its user friendly nature and did not become a handful KXF450 like monster just a absolutly flawless running missile.
Thanks Dangermouse for the effort and coming here and letting us all know.