300/440/550 440???????????

[KEVIN26]

so
I got this 440 and it does start and go
but it wont pickup and really go
you know what i mean
up to half throttle it acts normal but if you go past 1/2 it doesn't do anything more
so i was thinking that maybe it is not getting enough fuel
the manual is not at all helpful on anything
so
can some one tell me what pop off pressure they run
and what jet size
and how many turns out
and etc.....

and just incase someone asks
because I thought it was this too
I have replaced the cdi and the stator
but not the relay and volt regulator

any help would be COOL and THANKS ahead of time

 

[the WaTeRhAwK]

what carb?

how heavy are you?

and what prop does it have?

 

[KEVIN26]

what carb?

how heavy are you?

and what prop does it have?

the carb is the OEM 38 Mikuni

i way 250 but another rider waying 180 has the same issue

the oem prop

 

[the WaTeRhAwK]

well, unless you're about 100 lbs, you ain't gettin' anything out of that setup, especially with a stock aluminum prop.

setting to begin with on the bn 38 are both needles set at 1 turn out.


you need a 550 top end, a 44 mm carb, and a stainless AM prop.

 

[Shonuff]

I'm pretty sure it's got the Jetlyne 15* prop in it still.

 

[the WaTeRhAwK]

I'm pretty sure it's got the Jetlyne 15* prop in it still.

that' still too much prop for a 440.

 

[KEVIN26]

well either way
your saying its the weight of the rider
but
the manual talks about a 200 pound rider
so it should handle the 180 rider fine
but
just for kicks
I am going to put a 90 pound rider on it and see what happens
but I wont get those results until summertime
so
until then you think I should just change the prop (what is your suggestions)
and the carb
and
when you say a 550 top end
do you mean put a 550 motor in it????

 

[tj1820]

Not really! u can do that or you can just rebuild the top end on your 440 motor using 550 top end like cylinder, pistons, head and so on! u just use the 440 bottom end! or u could go ahead and just replace the whole motor with a 550 either way! i am in the process of rebuilding the top end of one of my 440s to a 550!! Good Luck and God Bless!

 

[the WaTeRhAwK]

well either way
your saying its the weight of the rider
but
the manual talks about a 200 pound rider
so it should handle the 180 rider fine
but
just for kicks
I am going to put a 90 pound rider on it and see what happens
but I wont get those results until summertime
so
until then you think I should just change the prop (what is your suggestions)
and the carb
and
when you say a 550 top end
do you mean put a 550 motor in it????

the manual can say all kinds of stuff, but what it boils down to is the condition of the motor. if the top end doesn't have a lot of hours on it, and it's basically like a brand new engine up top, you can get decent power out of it (kindof). meager "performance" at best, without tons of top end modifications done to the 440 cylinder.

put a 550 cylinder on it, 13 degree stainless prop, 44mm carb, top-loader intake grate. you will have a performance machine that will "rip" with a 200+lb rider.

yeah, you throw a 90 lb. rider on it like it is and it will probably do pretty good, if the top end is in good shape, and the carb is tuned good, even with the stock crappy aluminum impeller.

to put the 550 top end on it, you'll need to make sure the 550 piston skirts can go down into the cases. post '81 cases will accept up to 1mm overbore pistons without being machined. if they're pre '81 cases, they will need to be machined to allow even stock 550 pistons to fit.

 

[KEVIN26]

Thanks WaterHawk

well Sho,
you ready for this????
and I just got your garage all clean and nice

hey did you finish that turf job?????

 

[agua]

clean the carbs and see how it does