Hey guys I have a 2000 yamah blaster. It has new piston, rings, gaskets, reeds, and air filter. It also has an aftermarket exhaust, but factory pipe or header. It won't hit the power band and bogs at 3/4 to full throttle. I talked to a friend and he said to reject it. Currently I believe its running rich as if I remove the airbox lid, it runs fine, but with it it bogs. I also tried a FMF power up jet kit, and factory jet was a 230. I tried the 350 on the jet kit and it poured smoke. I tried the 210 and it did about the same as the 230 and still bogged. My friend told me I need to rejet the pilot jet, he's stating it as the air jet, but I've been told it doesn't effect 3/4 to full throttle as he said it did. If not, the do I need to go with about a 140-160 or so jet in it? Thanks in advanced guys!!!!
Need help! Driving me nuts!
- Thread starter CHEVY_TRUCKS_72
- Start date
First thing is that unless you use genuine Mikuni jets, others have no clue as to what you really have.
Then your post is a bit confusing
It ran better with the 230 with lid off? What air filter do you have? As to exhaust, you have stock pipe and aftermarket silencer?
Tho a plug chop or plug "read" is only way to confirm jetting, a quick and "dirty" way is when you get to the point it starts to bog, pull the choke half way out. If it gets better, you are lean.
As to the pilot jet, don't think I've ever seen anyone need more than stock, no matter the set-up.
Then your post is a bit confusing
It ran better with the 230 with lid off? What air filter do you have? As to exhaust, you have stock pipe and aftermarket silencer?Tho a plug chop or plug "read" is only way to confirm jetting, a quick and "dirty" way is when you get to the point it starts to bog, pull the choke half way out. If it gets better, you are lean.
As to the pilot jet, don't think I've ever seen anyone need more than stock, no matter the set-up.
The air screw is 1 and 1/2. Twin air air filter. Yea stock pipe aftermarket silencer.First thing is that unless you use genuine Mikuni jets, others have no clue as to what you really have.
Then your post is a bit confusing
Tho a plug chop or plug "read" is only way to confirm jetting, a quick and "dirty" way is when you get to the point it starts to bog, pull the choke half way out. If it gets better, you are lean.
As to the pilot jet, don't think I've ever seen anyone need more than stock, no matter the set-up.
And yes it did indeed run so much better with the lid off.First thing is that unless you use genuine Mikuni jets, others have no clue as to what you really have.
Then your post is a bit confusing
Tho a plug chop or plug "read" is only way to confirm jetting, a quick and "dirty" way is when you get to the point it starts to bog, pull the choke half way out. If it gets better, you are lean.
As to the pilot jet, don't think I've ever seen anyone need more than stock, no matter the set-up.
Leak test!
Set the float level, and make sure the needle and seat is clean and working.
Use genuine jets, with the needle in the middle clip position!
32.5 pilot jet!
Set the idle as per specs!
Plug chop to confirm jetting!
Set the float level, and make sure the needle and seat is clean and working.
Use genuine jets, with the needle in the middle clip position!
32.5 pilot jet!
Set the idle as per specs!
Plug chop to confirm jetting!
The
There are no leaks, I had it tested by a local ATV shop. Only place I could see a leak is in the hose the original oil take hooked up to. I need to set the floats I think but I don't have the tool, my train of thought is I could have sworn I seen on here one day someone said not to go below factory main jet. Well I'm running reallyyyyy rich and all.
Yamaha did supply some with a 220 main. How you are rich with a 210 with air box lid off doesn't sound right. That is unless you have some type of clog or something somewhere that is limiting the total flow of air/fuel through the motor, and or you are flooding it via the float height is incorrect or bad needle and seat..
Ex; something plugging your exhaust either in the silencer or the expansion chamber.
Also if you are no longer running the oil injection than the inlet on the carb where the oil line used to go needs to be plugged/capped
Ex; something plugging your exhaust either in the silencer or the expansion chamber.
Also if you are no longer running the oil injection than the inlet on the carb where the oil line used to go needs to be plugged/capped
Plugged or capped? I'm confused. And no it is perfect on 210 with no lid but I hit some mud sometimes so I don't want no lid I want to keep the lid. 230 without lid is good. With lid it bogs and don't hit power band
I covered that place in rtv silicone. I also pulled the gear from the oil injection. I still have a massive hose like 5 foot long that comes from the side of the crank case. Its a whitish yellowish color
I wouldn't go lower the the stock 230 jet size with ur mods unless u r going to ride on mt Everest
U need to do a leak test before u start jetting
U need to do a leak test before u start jetting
Was the leak test performed like this?
Loose that jet kit, buy some genuine jets, kits seldom can be relied on for the correct sizes.
Set the float level, adjust the idle and plug chop to see where the air fuel ratio is.
What oil and oil ratio are you using?
Have you performed heat cycles and re torqued the nuts?
Loose that jet kit, buy some genuine jets, kits seldom can be relied on for the correct sizes.
Set the float level, adjust the idle and plug chop to see where the air fuel ratio is.
What oil and oil ratio are you using?
Have you performed heat cycles and re torqued the nuts?
Before you make the plug chop run it is important that the float level is correct, the idle is set correctly and there are no air leaks in the system, otherwise the smoke ring may lie about the AFR.
WHEN ALL OF THE ABOVE ARE CORRECT PROCEED WITH THE FOLLOWING.
Warm up motor to operating temp.
Fit new B8ES plug, ride WOT through the gears and hold WOT in 5th or 6th gear for 10 seconds, or as long as you can safely.
Switch off the motor and pull in the clutch, apply brakes to come to a stop quickly.
Take the plug out and replace the old one for the ride home.
Carefully cut the threaded end off the plug to expose the insulator.
There should be a smoke ring of a cardboard or biscuit colour around the insulator.
If it is non existant or a very light colour, you are lean and require a larger main jet.
If it is a lot darker you are rich and may go down a size in main.
I prefer to run a little on the darker side, I may loose a little power but it is worth it for the peace of mind that I won't need a rebuild so soon.
You have to get up a reasonable speed so that you can get the motor to pull strongly.
Then hold it Wide Open Throttle (WOT) for 10 secs or as long as you can.
The idea is not to get speed but to make it pull strong at full throttle to get onto the main jet circuit.
I find I can safely do it on a short run by applying the brakes some.
If you have not enough room you can use 4th or 5th gear with good results.
WHEN ALL OF THE ABOVE ARE CORRECT PROCEED WITH THE FOLLOWING.
Warm up motor to operating temp.
Fit new B8ES plug, ride WOT through the gears and hold WOT in 5th or 6th gear for 10 seconds, or as long as you can safely.
Switch off the motor and pull in the clutch, apply brakes to come to a stop quickly.
Take the plug out and replace the old one for the ride home.
Carefully cut the threaded end off the plug to expose the insulator.
There should be a smoke ring of a cardboard or biscuit colour around the insulator.
If it is non existant or a very light colour, you are lean and require a larger main jet.
If it is a lot darker you are rich and may go down a size in main.
I prefer to run a little on the darker side, I may loose a little power but it is worth it for the peace of mind that I won't need a rebuild so soon.
You have to get up a reasonable speed so that you can get the motor to pull strongly.
Then hold it Wide Open Throttle (WOT) for 10 secs or as long as you can.
The idea is not to get speed but to make it pull strong at full throttle to get onto the main jet circuit.
I find I can safely do it on a short run by applying the brakes some.
If you have not enough room you can use 4th or 5th gear with good results.
Before i buy anything I plan to set floats. Currently I'm running 40-1 with klotz super techniplate. Idle seems to be correct but quad smokes entirely too bad
I can't ride it in first gear. It won't hit the powerband. It just bogs and stalls.
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