ok will do. i will be installing them this weekend then after everything is installed i will do another leakdown to make sure its all air tight!
carb rejetting
- Thread starter 89blaster89
- Start date
ok will do. i will be installing them this weekend then after everything is installed i will do another leakdown to make sure its all air tight!
ok so i just got it idleing, i started with air out 1.5 turns then i got the idle screw to a fast idle its about little less than half way in an the air screw is out 2 turns from all the way in turns does that sound right?
oh and by the way is making like a little gasket for the exhaust flange ok if its outta cardboard
Cardboard will cook and shrink then eventually burn away.
You could use it, but only as a last resort, and not for long term running.
So I guess the leak down test confirmed no leaks.
At 2 turns out on the air screw, you are on the limit, but if it is idling there ok, it is time to plug chop to see if the main is ok.
So I guess the leak down test confirmed no leaks.
At 2 turns out on the air screw, you are on the limit, but if it is idling there ok, it is time to plug chop to see if the main is ok.
Did you do it this way?
Start with air screw 1.5 turns out.
Turn the idle screw in so that you get some revs to warm the motor up.
Warm up motor and then set idle screw for a fast idle.
Adjust air screw either way, in or out, to get the fastest idle.
Re adjust idle screw to desired idle.
yea i did exactly that, and yes no air leaks it held 6 1/2 psi for 10 minutes and i used soapy water
Presuming your sig mods are right and it is not a fresh rebuild.
Pop in a #280 and do a plug chop on a new b8es plug.
Pop in a #280 and do a plug chop on a new b8es plug.
i dont think this is very accurate because ii disint have a big enough space to get in to 6th but i baerely got in to 5th and then i tried doing it again on the same plug and got kinda a gray looking color around the white parti tried to cut itdown but im not so goodat it
, im not able to post pics because i hve no phone currently or camera.
also do you think i could do a plug chopp by just haveing it in 4th WOT gear for around 7 seconds?
update...i was looking on myold plug, ive used it in my blaster just going around in 1st or second gear for about 15 minutes and the white insulater is a little darker then bisuit color (i like it like that color so i can be on the safe side) and the end of my 4th gear WOT plug is like white colored, it says thats normal in my clymers. so i think its good
Plug chop.
You need to do it this way!!!!
If you can only get WOT in 4th gear you should still be able to get enough ring for a good reading!
Warm up motor to operating temp.
Fit new B8ES plug, ride through the gears and hold WOT in 5th or 6th gear for 10 seconds, or as long as you can safely. 4 th gear for you WOT and make the motor really pull!
Switch of the motor and pull in the clutch, roll to a stop.
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.
..............................................................................................
Just going around in 1st or second gear for about 15 minutes, and my plug would be black, and I should like to feel that my jetting is just right.
I am not about to dissagree with the writers of a manual, but in my book, like white coloured aint good enough.
The smoke ring on the insulator should be of a cardboard or biscuit colur, for perfect jetting. I like it slightly darker as I prefer to run richer than the norm.
You need to do it this way!!!!
If you can only get WOT in 4th gear you should still be able to get enough ring for a good reading!
Warm up motor to operating temp.
Fit new B8ES plug, ride through the gears and hold WOT in 5th or 6th gear for 10 seconds, or as long as you can safely. 4 th gear for you WOT and make the motor really pull!
Switch of the motor and pull in the clutch, roll to a stop.
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.
..............................................................................................
Just going around in 1st or second gear for about 15 minutes, and my plug would be black, and I should like to feel that my jetting is just right.
I am not about to dissagree with the writers of a manual, but in my book, like white coloured aint good enough.
The smoke ring on the insulator should be of a cardboard or biscuit colur, for perfect jetting. I like it slightly darker as I prefer to run richer than the norm.
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1989 yamaha blaster fmf fatty pipe
unknown silencer
wiseco piston and rings
twin air air filter, lid removed
32.5 pilot, 280 main jet
ceet racing seat cover
oil injection block off with 32:1 mix ratio
If these are your mods a #290 main, with the needle on the second from bottom clip, should be good to ride, but do not hold me to it as all motors will breathe differently.
unknown silencer
wiseco piston and rings
twin air air filter, lid removed
32.5 pilot, 280 main jet
ceet racing seat cover
oil injection block off with 32:1 mix ratio
If these are your mods a #290 main, with the needle on the second from bottom clip, should be good to ride, but do not hold me to it as all motors will breathe differently.
ok well i will do a 4th gear wot and make the motor pull, and then chop the plug and ifits that right color im runnin good on a 280 main with clipon middle slot right
ok so i did a wot 4th then i tried to get it into 5th for a second or two, i cut the plug and got a somewhat light biscuit color, when i did it i had a 280 jet in withclip on middle, so i was thinking i will do it once again with the saim main and clip position and then if i still dont get that biscuit color i will do 290 with clip on 2nd to bottom like you said. does gas/oil mix ratio change anything?
Most certainly.
MORE OIL= LESS FUEL = Lean mix, and vive versa.
I changed pre mix from 32:1 with Castrol R30 to 25:1, and needed one size bigger main.
well i currently mix 1 quart of oil with 5 gallons of gas and what would youu say about the clor i had after my 4th gear wot plug chop the color is light greyish brown
