ok now i have a 1990 Yamaha Blaster that i got off my friend for free. yes free.

well i know it has
- 240 wiseco piston kit
- after market reeds
- FMF pipe

now i had a carb on the bike and got it running (one of the reasons why he gave it to me cause it wasn't starting) and after running the bike it stoped in the yard and i noticed that the Air Screw / Idle Screw was missing (Lost) . i went around to all of the places that carry Yamaha ATV's and no one could help me on getting the part that rattled out of the carb (different carb than stock so they said).

so i decided to just BUY a new carb that came with extra jets and the TORS unit to install for after market parts (i removed the TORS box and reinstalled my wrist throttle)

i bought a 2003 Blaster carb and accually didn't touch a thing on the carb just installed it and kicked it and it started right up. but one thing i noticed is that you can't give it full throttle cause it "Bogs down" or like its running really rich. (it smoked alot) so i turned off the bike cause the carb is a bit different from the other carb that was on the bike. and now sold the old carb i can't tell how big the difference was between the two but i can tell there was a big difference in size between the two from the carb i had on it Minkuni ??mm (had a paddle choke) Vs. the 2003 stock 26mm. that i dont know which screw to adjust the idle and A/F Mix ratio.

the extra jets that came with the carb say on the sides of them "250" "260" "270" "280" so i dont know if i need to install one of these jets or not or how i can get this carb tuned right. please someone dont tell me that i need to get a different carb. i really want to get my bike running. please help.... aaaaaaahhhhhhhhhhhh!!!![img]i/expressions/face-icon-small-confused.gif[/img]

 

If you have a 240 kit on your blaster a new, bigger, carb would help you ALOT. You should be looking at somthing of more around a 33mm.
The stock one that you have now will work fortunally. However you can't expect a stock carb to be able to bolt onto a motor that has a extra 40cc, better pipes, and reeds, the jets in the stock carb aren't ment for all this after market stuff. What you are going to have to do is spend some wrench time, get your hands dirty and jet the carb. Its just a matter of trial and error. If it is only running real bad at the top end then you'll be looking to play around with the main jets a little.

Read This If you don't know how to jet already this will make it ALOT easier for you to do.

 

Might want to check the gap on the plug too. Friend's daughter has a lil clutchless 70, and it fouls the plug almost everytime it gets ridden. Increasing the gap seemed to extend the life a bit.

 

thank you both for the help.

i'm already looking in at getting a 33mm or 34mm carb with the proper jets for it.

but i'm having a friend that knows a bit about these carbs to come over and help me out. i'd hate to mess something up on the carb and distroy it, still learning this bike. i had a 1985 yamaha 80cc but that was a little bit ago. so i'm trying to catch up on technology with these new carbs.

the gap on the NGK plugs that i bought were pre-set but i checked that as well and it seems to be fine.

this carb just looks alot different than the other one that i had on the bike in size mostly and some of the mixture screws arent the same.

OLD CARB:
had like i said the paddle choke and a big Idle/Air screw in it. and kinda knew my way around the carb.

NEW CARB:
doesnt have the Idle / Air screw that the old one had it has a place for it but there is no way all the way through.(like it wasn't designed this way) and it seems to have only one screw for adjustment and i have no idea what this screw does on the side where the pull choke is on. (flat faced phillips head screw)

I have about 1 day to get this bike running cause i want to go ridding this saturday, even if it doesnt have the same torque and power.

(before) i could hit 2nd gear and about 3/4 throttle it would pull the front tires off the ground, so even if i dont have that amount of torque / power i would like to get it so that i can RAP this bike out.

THANK YOU ALL AGAIN.

 

no problem dude. Just make sure that if you are going out riding and you havn't got it just right that you are not running tooo leann. If anything you would be better off being a little rich. If your carb is to lean then you might end up having more problems then just the carb

 

yea i know that one atleast... LOL

i also drive a 11. sec 1998 Mustang GT so i know all about the Lean Factor. i'll be sure to not let this happen to the bike.


thanks agian.

 

OK NOW I'M GETTING FRUSTRATED!!!!!!!!!!!!!!!!

ok so i have been reading online about these carbs for 3 days now and still cant seem to get this damn bike to run right.

i broke open the bottom of the bowl and saw that the main jet was a 300 (stock from what i'm told) and i went out and knew i'd have to make a big adjustment on the jetting but i went one at a time starting with 310 then 320 then 330. still it will start after many kicks now but the idle is adjusted through the cable i see as the TORS unit was configured. but still at 3/4 throttle i'm still getting the "poping" on deaceleration and it still will not "RAP" all the way out.


so if there are anyone out there that can just kinda give me a better idea on which jets to install or how much bigger in main jet size i need to buy i will but i'd hate to keep buying jets when they will not work.

i know i need a bigger carb but i want to get this running atleast if i can at all possible. i guess i didnt' know as much as i thought about these carbs.

After changing the Main Jet sizes do i need to install any other Larger Jets anywhere else on the carb?

someone please give me the breakdown in their terms cause i have read and read , and read all the turning FAQ's and such all over.