my 2000 blaster is awesome from mid to high range but the low end is kind of boggy. what could it be?
sluggish low end
- Thread starter bigred85
- Start date
It could be your pilot jet. It may be a little dirty or the wrong size. I would do a good cleaning on the carb and see if it still does it.
i have reworked the carb several times and it still does it. by the way it is bored 80-over, ported and polished, wiseco piston, boyesen carbon reeds, profilter air filter,DG header with fat boy silencer, if that helps.
the compression is fine, i think it might have something to do with the jets, what jets would you recommend for my setup? and my airscrew is 2 turns out.
^^^^^^^The DG header is very basic and is never going to give you any thing much better than a stock pipe.
You may be able to increase the bottom end some using a reed spacer block in conjunction with a +3-4 deg timing mod.
Was the porting done before or after you bought it? Did you do it or have it done? What "style" is it supposed to be? When did it start acting this way? In general what does your plug look like? Is it when you stab the throttle or cruising at a certain throttle? What throttle setting, 0-1/8 or 1/8-1/4? Is this stock carb? What needle and what clip posistion? Have you actually pulled the pilot jet out when cleaning or do you just spray it and say good? Pull the pilot and actually look at it , make sure the holes on the side of it are clear and you can blow air thru the circut.
There is the possibility that the combination of the porting and pipe may cause the problem, humps and hollows in the power band. I doubt that a reed spacer will make a difference, tho if you can borrow one to try do it. But I wouldn't spend the money unless everything else you try does nothing or you just can't live with the flat spot.
If you can take and cruise at 0-1/8 then 1/8-1/4 then 1/4-3/8 throttle and describe how it runs at each of these throttle openings. Be sure you don't have excess slack in throttle cable for this test.
There is the possibility that the combination of the porting and pipe may cause the problem, humps and hollows in the power band. I doubt that a reed spacer will make a difference, tho if you can borrow one to try do it. But I wouldn't spend the money unless everything else you try does nothing or you just can't live with the flat spot.
If you can take and cruise at 0-1/8 then 1/8-1/4 then 1/4-3/8 throttle and describe how it runs at each of these throttle openings. Be sure you don't have excess slack in throttle cable for this test.
its just at 0-1/4 and yes i took the pilot out, and it is a stock carb and the plug is paper sack brown like it should be.and stock needle and clip position.
it is sputtery at 0-1/4, and just awesome the rest of the way, and it was ported before i bought it.
Try turning air screw up to 1/2 turn each way to see if it gets better. Might need next size larger pilot.
this does sound like an airscrew setting, or needle clip position problem
i always adust the airscrew to what setting gives it the highest rpm's, then adjust idle with the idle screw
have you tried different clip positions on the needle??
and that main does sound lean for a ported motor,
but that should not effect anything under 3/4 throttle postion,
that DG pipe could very well be "hindering" the rest of your mods
heres a good article that describes ways to figure out what your machine is doing at each throttle position (near the bottom if the article)
http://www.blasterforum.com/do-yourself-20/jetting-101-everything-explained-1625/
i've also gotta ask...
is your air filter clean and oiled properly ?
if running mixed fuel/oil....is the injection inlet on the carb plugged off ?
is the float level correct ?
are the reeds in good shape...no cracks/chips, and laying flat/closing comepletely ?
is this motor air leak proof ? heres some info on that........
http://www.blasterforum.com/do-yourself-20/videos-how-perform-air-leakdown-test-31464/
http://www.blasterforum.com/do-yourself-20/build-use-leakdown-tester-10663/
i always adust the airscrew to what setting gives it the highest rpm's, then adjust idle with the idle screw
have you tried different clip positions on the needle??
and that main does sound lean for a ported motor,
but that should not effect anything under 3/4 throttle postion,
that DG pipe could very well be "hindering" the rest of your mods
heres a good article that describes ways to figure out what your machine is doing at each throttle position (near the bottom if the article)
http://www.blasterforum.com/do-yourself-20/jetting-101-everything-explained-1625/
i've also gotta ask...
is your air filter clean and oiled properly ?
if running mixed fuel/oil....is the injection inlet on the carb plugged off ?
is the float level correct ?
are the reeds in good shape...no cracks/chips, and laying flat/closing comepletely ?
is this motor air leak proof ? heres some info on that........
http://www.blasterforum.com/do-yourself-20/videos-how-perform-air-leakdown-test-31464/
http://www.blasterforum.com/do-yourself-20/build-use-leakdown-tester-10663/
Stock jetting with this setup is a recipe for disaster, it is gonna be running lean, especially if it is cold there.
The main should be changed to the region of #260 - #270 and then do a plug chop with a new b8es plug.
A #32.5 pilot is the right jet to use unless the motor is heavily modded.
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