Need jetting opinions

Smitty jr

Member
Oct 6, 2017
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Hey everyone I’m new to blaster forms but not new to the mechanics world I don’t get to ride much yet but I just got done the majority of my blaster rebuild and am having some jetting issues I think! Here’s what I know off the top of my head!

Exhaust: FMF gold series fatty with powercore2
Airbox: stock box no lid w/ cheap pre oiled filter
Carb: mikuni vm26(pretty sure)
Main Jet: 220
Pilot jet: 32.5
Crank: stock
Cylinder: stock
Head: stock
Reeds: Boysen pro series carbon fiber
Oil pump: stock pump (considering premix)

So it can idle fine with choke off but won’t idle with choke out however it will not really move unless choke is out. The bike just bogs right out when I hit the throttle unless I go extremely slow on the throttle and when I’m at an idle with the choke off and hit the throttle it bogs out unless I nearly touch the throttle so I’m guessing it needs a bigger jet. Any opinions would be appreciated and thanks in advance!!
 

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Look in the carb section for threads on.... float heights, adjust airscrew/pilot, and plug chops for main jetting. And do them in that order......
http://www.blasterforum.com/forums/carburetor.138/


stock 32.5 pilot, airscrew at 1.5 turns out to start, and the needle clip should be in the middle position

Main jetting.....
Buy 270 thru 300 main jets, start large and plug chop down.
 
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Hi thanks for the link I did happen to see that post before I posted but just wasn’t sure the jet size I should go for I forgot to also mention I’m only 150’ - 200’ above sea level is this going to make a huge impact on the jet size??
 
what is sticking out of airbox side boot?
i highly doubt your main jet and pilot jet is your problem
unless you have not taken carb apart and cleaned the jets
with carb cleaner and soaked the pilot jet in container/you should be able to hold it up to a light and see through it .
yes 220 main is to small for fmf but it would not produce your issue
what is the airscrew set at?
what year is it?
everything has been spray painted to make sure
there is no paint where the electrical grounds are on frame.
answer that first lol
 
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what is sticking out of airbox side boot?
i highly doubt your main jet and pilot jet is your problem
yes 220 main is to small for fmf but it would not produce your issue
what is the airscrew set at?
what year is it?
everything has been spray painted to make sure
there is no paint where the electrical grounds are on frame.
answer that first lol

Lol it’s a metal sleeve insert the old owner threw in the airbox tube to connect it to the carb but it had a bigger carb on there I guess but the kid I bought it from had thrown it out cleaning his garage sooo I bought a new stock mikuni carb thinking it would be ok lol but those pics r from the night I got it running I have sense used a rubber boot off another carb to connect the carb to the the sleeve temporarily until I can replace the whole airbox any suggestions on what I should put for an air system if there’s anything better than the stock blaster airbox haven’t done much research on that yet but I made sure I had a good connection to the airbox before I messed with the settings on the carb and the the airscrew I’m not sure off the top of my head what I have it set to at the moment I’m not with my bike unfortunately where I live I can’t keep it here it will be stolen within 48hrs im sure lol but when I go over to it I’ll have to write down the screw turns I think it’s closer to being in but not totally sure yet and all my grounds r good the bikes not shutting down cause of electrical issues it’s not getting enough fuel it seems like but I could be wrong I’m not saying your wrong lol but I would assume with electrical it would just shut right down or not run at all. I can ride it with the choke open but it won’t idle with the choke open and with the choke off it isles but can’t ride with it off cause the motor bogs right down unless I bearly touch the throttle and even then it takes time to build up speed if that makes sense lmao
 
and the truth shall set you free lol
that is a chinese knock off carb looks SHINY
where did you buy it?

I don’t buy that cheap Chinese knock off sh*t it’s a mikuni carb they have always been decent carbs as my experience goes with them I’ll post a exact pic of the carb tomorrow it’s a mikuni vm26 not those $20 Chinese sh*t carbs from eBay I don’t trust knock off sh*t and wouldn’t even waste my money I put a lots of hrs and money into my bike and don’t plan on seizing my motor over a sh*t carb lmao! But regardless most things r foreign made even nice expensive carbs u buy so where it’s made doesn’t have much to do with it but I agree %100 not to waste time or money with cheap carbs
 
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And I’m not done with my build btw I still have lots of work left To do but have been squeezing in hours in between providing for my family and working my ass off 65hrs a week trying to get this rebuilt and running so sorry if everything isn’t up to everyone else’s nice modded blasters but rome wasn’t built in a day lmao jk but seriously I have been rebuilding it for the past six months sense I first bought the bike I didn’t even try to get it going first I just ripped it down and put even dime I had into it for parts (not cheap parts but not overpriced parts either) and I just have been sandblasting every things and painting it all again except fenders and shocks and handlebars and front hubs other than that I think I touched every single nut bolt on it! Just wanted to throw that out there I’m not one of those people who r like hey I rebuilt my bike I spray painted everything look how nice it looks now I hate people like that they have no respect for machines n shouldn’t waste there time
 
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you would half to list everything
you had to do to get it running
check the tors system as well
have you seen this or checked it out??
if it is a 88-02 just unplug the connector under front nose
http://www.blasterforum.com/threads/how-to-remove-your-tors-88-02-models.655/
or 03-06
http://www.blasterforum.com/threads/03-06-tors-removal-diy.41973/

Thanks for the info! I didn’t have to mess with the wiring when I got the bike it already had the tors system properly disconnected I made sure it was removed before I started putting the bike together, the only tors wires left are in the throttle housing but they r not hooked up nothing to do with the tors is connected. I truly believe it’s just a main jet being to small but I wanted to make sure I ordered the right sizes so I’m not wasting money lol and yes the entire rebuild was not the best because I simply don’t have the cash to build it the way I wanted to but I enjoy doing the build myself but I still have tons of stuff to do it’s far from being done lol so back to the topic if this was a tors problem what would cause it to only bog down when at half throttle to full throttle?
 
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the tors would make it not rev at all
just do whatever you think is right:)

Ok that’s what I was figuring thanks for the help I really appreciate it!! I think I’m going to start with the 300 Work down wiTh the plug chops and go from there lol