Currently I use 170 main, 48 pilot, 55 leak for an 07 450er. I also have a dyno jet needle on the third clip. I also live at 40 ft of elev. i do believe 170 is a tad rich and I might bump it down to 168 after a couple more rides. I think Monster is the best pipe out there. It sounds and performs so great.
Tuning for monster pipe and air box lid
I need help tuning my 450r. I just installed a monster pipe and run it without the air box lid. After about 45 seconds of idoling it just shuts off and also shuts off at about 1/4 throttle. Just looking to see what jet sizes are recommended and if I need to adjust the needle etc.
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I need help tuning my 450r. I just installed a monster pipe and run it without the air box lid. After about 45 seconds of idoling it just shuts off and also shuts off at about 1/4 throttle. Just looking to see what jet sizes are recommended and if I need to adjust the needle etc.
did you adjust the needle rings at all?Currently I use 170 main, 48 pilot, 55 leak for an 07 450er. I also have a dyno jet needle on the third clip. I also live at 40 ft of elev. i do believe 170 is a tad rich and I might bump it down to 168 after a couple more rides. I think Monster is the best pipe out there. It sounds and performs so great.
If it just shuts off it might not be jets, I’d first turn up your idle some, then check your TPS on the carb, if it’s not bypassed, I recommend bypassing it cuz they tend to cause the cut out issue your experiencing. Does it start right up after it shuts off?I need help tuning my 450r. I just installed a monster pipe and run it without the air box lid. After about 45 seconds of idoling it just shuts off and also shuts off at about 1/4 throttle. Just looking to see what jet sizes are recommended and if I need to adjust the needle etc.
Did it do this before the exhaust & lid mod?If it just shuts off it might not be jets, I’d first turn up your idle some, then check your TPS on the carb, if it’s not bypassed, I recommend bypassing it cuz they tend to cause the cut out issue your experiencing. Does it start right up after it shuts off?
Have you rejetted at all since you put the pipe on and removed the lid? You can‘t just throw performance mods on there and not add fuel. You are going to be running super lean and causing the engine to run very hot and knock which can cause severe problems and engine damage.
The clip is on 4th ring from the top on a dyno jet needle, not the third as I mentioned previously and I am 1 and 7/8 turns out on the Air fuel mixture screw. Also I changed the timing of the Leak jet using the D screw on the Carb 1/2 turn out. As for that special d screw here is a hack: get a 6.5 brass case smash one end flat and presto perfect fit. If you have 05 or earlier this jetting will be way too lean. This seems to be the setup in my opinion for 07 with an fcr carb. Remember, do your jetting first, then adjust the the air mixture screw and then adjust the idle. There is a really good thread how to do this by a member named 450rrr. I think a good place to start, depending on your elevation, is the main 165 with a 45 pilot and 55 leak. Ride it and adjust as necessary. As for the stalling at 1/4 throttle if you haven't adjusted the jets, My bet is that it will fix itself with the right jetting. As for the idle issues, after it is jetted properly and then if you set the idle it will probably clean up once the jetting and air mixture screw is set correctly if it ran fine before the install.did you adjust the needle rings at all?
Jetting Questions
Just now realized the reason it shut off idling was cause I turned off the fuel to let it run and drain the carb before taking apart 🤦♂️ so I think it’s idoling ok (it’s got a 48 pilot which I assume is perfect) but it still shuts off after giving it gasDid it do this before the exhaust & lid mod?
Yeah that’s why I’m trying to figure out how I should tune the carb for what I have…Have you rejetted at all since you put the pipe on and removed the lid? You can‘t just throw performance mods on there and not add fuel. You are going to be running super lean and causing the engine to run very hot and knock which can cause severe problems and engine damage.
Also completely forgot to mention that I have an 04 model carb so I assume our herrings would be different? And leak jet is not adjustable?
Ahhh so you should be i bit higher on your main then, try a 185-190 main, Keep the pilot the same (48) if it’s starting and idling good and put the clip on middle slot of needle. That should get you in the ball park. 04/05,s run higher mains than 06+. And mr. Lew is right that write up about jetting is very informative. Read it 3 times in a row like I did and youl have better clarity on jetting process.Also completely forgot to mention that I have an 04 model carb so I assume our herrings would be different? And leak jet is not adjustable?
I also find it much easier to do one thing (jet) at a time i.e. the pilot first then your needle last your main jet. Once she’s running good adjust idle and screw. Jmo
Thanks I’ll let you know how it goes.
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