Yamaha blaster sputtering

2strokeAdict

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Nov 28, 2016
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Hey what's up guys
I got this blaster thinking nothing was wrong with it and ended up replacing both crank cases along with crank bearings, new piston, new spark plug, 100 psi compression, reeds are new as well, the bike idles really good. But when you go to ride it, it sputters. No power what so ever. I've messed with the tuning, as well as the needle adjustment it's at the 3rd groove atm. TORS is canceled, when running low on fuel it runs how it should. My guess is it's either not burning fuel or it's throwing too much fuel.. I would appreciate if some one could give me some advice in where else to look?
 
Welcome !!!

Explain how you did your comp test, as mentioned, sounds low. Clean carb and set float level. Is air filter clean? What spark plug did you use? Explain how you "canceled" the tors. What year is your Blaster.
 
Welcome !!!

Explain how you did your comp test, as mentioned, sounds low. Clean carb and set float level. Is air filter clean? What spark plug did you use? Explain how you "canceled" the tors. What year is your Blaster.
I connected the compression Guage where the spark plug goes and I made sure it was tight. I'm running the carburetor straight no filter. I cleaned the carb 2-3 times taking out the jets and everything. I forgot to mention the bike was sitting for a while. I didn't completely cancel the tors I just unplugged everything that includes the tors (the plug that goes from the throttle, the front is next to the cdi box and the carb plug.) spark plug BR9ES Ngk year is 2002
 
are you sure it is at 100psi of compression that is low for a top end rebuild.
it should be at 120psi or more on new top end at least.
Yeah I agree it's low but I'm sure it's at 100 if you guys would like look up "2strokeAdict on YouTube I have a video of what it does
 
it takes a ngk br8es or b8es.
-you have low compression
-wrong spark plug..get rid of the 9 it is to cold of a plug.
-and no air filter is crazy,hope you dont ride it like that?
and make sure you hold throttle wide open and kick it till it stops rising to do your compression test.

also i dont see no video on your youtube channel
 
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it takes a ngk br8es or b8es.
-you have low compression
-wrong spark plug..get ride of the 9 it is to cold of a plug.
-and no air filter is crazy,hope you dont ride it like that?
and make sure you hold throttle wide open and kick it till it stops rising to do your compression test.

also i dont see no video on your youtube channel
I ride it with no filter because I feel like it was running rich. I will buy the spark plug tomorrow and install and keep you updated. Here is the video. And I don't hold throttle open lol! Wow I've been doing it wrong all along
 
yes you have the wrong spark plug.NOT going to help it running rich
and yes you need to full throttle the thumb throttle and hold it to do a compression test:D
search how to check compression.ON your browser
and your video still does not work you did it wrong lol:)
 
not saying this is the best example but it is close to what should be done.
1 reason is the length of the hose connected can alter the reading,and also some compression gauges LIE.

 
yes you have the wrong spark plug.NOT going to help it running rich
and yes you need to full throttle the thumb throttle and hold it to do a compression test:D
search how to check compression.ON your browser
and your video still does not work you did it wrong lol:)
So what do you think I should look at next since it's not going to help the fact that it's running too rich?
 
And I replaced the spark plug.. still the same problem. It has too be is spark issue. Because how could the carb throw so much fuel.. it idles perfect.. 110 is low I agree but not to the point where it sputters so bad. Like it has no power what so ever
 
But then I second guess myself because when it runs low on fuel, power band hits and it feels good. So there goes my guess to the carb. Idk.. far past my knowledge.
 
Well it was doing this exact thing when I got it, and I ended up Checking if the crank seals were bad and I ended up splitting the cases to change the seals and it ended up being the cases were cracked. I doubt there's any oil getting in there but I could check again.. and I don't think it's the woodruff key just because I've taken the motor part 3 times and still does the same thing. and if I leave the gas cap open wouldn't that have the gas flow faster to the carb?
And yes I ended up messing with the tune and the needle adjustment and it revs healthy now, but it still runs like crap. It idles really healthy as well
 
Riding with no air filter can destroy the cylinder in one ride if it is dusty:
full

FRIENDS DON'T LET FRIENDS RIDE WITHOUT FILTERS!
Clean it or buy a new one.
Do not clean foam air filters with hot water. They are often made with hot melt glue.

About the plug, what they are telling you is too cold a plug can act like too rich.
BUY A NEW PLUG in the right heat range.
In fact buy a few and do a plug chop to see if your jetting is right.

Steve
 
Riding with no air filter can destroy the cylinder in one ride if it is dusty:
full

FRIENDS DON'T LET FRIENDS RIDE WITHOUT FILTERS!
Clean it or buy a new one.
Do not clean foam air filters with hot water. They are often made with hot melt glue.

About the plug, what they are telling you is too cold a plug can act like too rich.
BUY A NEW PLUG in the right heat range.
In fact buy a few and do a plug chop to see if your jetting is right.

Steve
I completely understand that riding with no air filter will ruin my cylinder. And I have a stock jet. Why would I need to go bigger? If my problem is too much fuel.
 
No filter, or an aftermarket free flow filter, allows more air in, which requires richer jetting.
 
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No filter, or an aftermarket free flow filter, allows more air in, which requires richer jetting.
But doesn't it make more sense that if you're running an open carb (no filter) you wouldnt you receive more intake? Correct me if I'm wrong.