fuel screw ?

[One_Bad_400]

i ordered a quiet core for my sparks exhaust and i've been messaging sparks about re-jetting. he mentioned going down a jet and adjusting the fuel screw. can someone please expain to me how to do the fuel screw. i figured i could talk to ya'll easyer then e-mailing him once a day clueless.

[speedracer350X]

The fuel screw stock is very hard to get at, and I think it's practically non-adustable. You'll have to get an aftermarket one (plenty to choose from) and replace your stock one. I put a Sparks on my '07 ER back in April w/ a quiet tip and Spark arrestor. I have it dialed in pretty good here in PA. I recommend a R@D adjustable fuel screw, Rocky Mountain sells them along with alot of other places. It was like $32 when I bought it last fall, but well worth it, you adjust it w/ you fingers. Invest in a service manual also, well worth it. I found it best just to take the whole carb off the machine to work on installing everthing, now it's just a matter of fine tuning the machine while it's running. I also found alot of good info on trx450r.org for the 450r.

[One_Bad_400]

how are you sure it is running right? what will the bike do when it is running right and when it is running wrong? i dont tune anything, i just run the hell out of it. lol

also, did you get the quiet or the extra quiet. how much did it quiet it down. how much do you think i need to come down on my jetting. i've got a 175 main in right now

[speedracer350X]

Sorry so late on the reply, just got back from vacation. Let me start off w/ my mods. #1 I bought a Sparks pipe last year and didn't actually put it on until this past April when my warranty ran out. So I had time for roughly a year to do my research as far as what and how I wanted to tune my pipe. I'm currently running a K@N air filter with an airbox lid that I cut 2 rectangular 2"x4" holes in the top of the lid. HRC needle a 45 pilot and a 165 main. The extra stuff I ordered from Sparks last year was a spark arrester cage insert and the "quiet" tip, not the "super quiet". After all, besides performance, we all love the sound of a fine tuned exhaust on any machine, be it a quad, truck etc.. But after riding for over 24 years, I personally can't stand an obnoxioulsy loud or poorly tuned exhaust. As far as you asking how do you know if it runs right or not, you'll know, you just have to play with the tuning a little at a time. Like I said, I've been riding since the 3 wheeler days, wish we had the internet back then for information sharing. But again, a lot of this info will get you in the ballpark, you'll still have to be patient and trial and errror your particular machine. Keep records where you start , and if you can't get it right in a day or when you work on it, put it away until the next day, and start over fresh. But like I said earlier, I did my research and listened to what worked for most other people running the same mods, and it put me really close to a tuned pipe, but I was glad I have and adjustable air/fuel screw, that's all I 've had to mess with for now after installing everything else. Hope this helps you out, I know it was kinda length!!!

[One_Bad_400]

did your sparks quiet tip work? i orders the extra quiet tip and i installed it the otehr day and it didnt tune down my exhaust noise AT ALL?!?! it just made it sound like a stock pipe with the baffle pulled out?!?!

[speedracer350X]

To be honest with you, I didn't even run it without the tip to compare a difference. To me, it sounds just right. I can still ride around the yard w/o p****** off the neighbors, but when I get on it, it sounds sweet to me. Trust me, I had a Cobra Jet on my 350X 3 wheeler years ago, it was obnoxiously too loud, gave me a headache while riding. I had a Power Core 4 slip on on my 400EX, that sounded OK, but my Sparks sounds just right. I guess it's just all matter of opinion now.