Yamaha blaster sputters at high rpm's once in a while

[evmini]

i have a 1998 yamaha blaster it runs very good untill a few weeks ago it started to sputter when im ryding down the straight strech once i hit 5th (high rpm) or 6th it will sometimes bog or quiet down and not gain speed it never did this before and would really like some help thanks in advance!

 

[evmini]

i have a problem please help ASAP

i have a 1998 yamaha blaster it runs very good untill a few weeks ago it started to sputter when im ryding down the straight strech once i hit 5th (high rpm) or 6th it will sometimes bog or quiet down and not gain speed it never did this before and would really like some help thanks in advance!

 

[bummer981]

Have you changed anything? Is your air filter clean? Fresh fuel? Carb clean? Good plug?
Leak tested lately?

 

[evmini]

so far i put a new plug cleaned the carb just put new gas and air filter is like new, im not able to do a leak test as i dont have the machine

 

[blasterdemon7]

I would check to see what fuel flow your getting from the tank. If you have a nice strong flow, then check float level.

 

[Awk08]

Re: i have a problem please help ASAP

edit....your 2 duplicate threads have been merged into 1


have you tried a new plug ?
check the plug boot for tight clean connection to the plug ?
checked all other connections (ground/power at the coil) for tight clean connection ?
high rpm hesitation is sometimes a sign of an electrical issuue
is it airtight ? it must be leakdown tested for leaks at the intake, head, base gaskets, and the crank seals
have you cleaned and properly oiled your airfilter lately ?
check the reeds for cracks/chips ?

if those check out, time to clean and tune your carb.
this is the road to a perfectly tuned carb, in this order ..........

the engine must be leakproof and proven so before any jetting can be done....
http://www.blasterforum.com/do-yours...blaster-13144/
or...
http://www.blasterforum.com/sale-18/...testers-55015/

properly clean the carb...
http://www.blasterforum.com/carburet...carb-pics-209/

set your floats..
http://www.blasterforum.com/carburet...st-them-50565/

repair or replace a leaky float valve...
http://www.blasterforum.com/carburet...y-carbs-33335/

adjust airscrew/pilot jet...
http://www.blasterforum.com/carburet...lot-jet-51060/

stock needle on the middle clip

plug chop main jet for your mods...
http://www.blasterforum.com/carburet...ug-chop-53237/

 

[evmini]

how could i check float level

 

[evmini]

thanks^ il try that and get back to you guys in a few days

 

[blasterdemon7]

how could i check float level

There's a link in awk08's post on how to do it.

 

[Blaaster]

It is possible to check the fuel level by attaching a length of clear plastic tubing to the drain nipple , lifting it up the side of the carby, and cracking the drain screw.

The fuel should show in the pipe to the level of the carb body above the float bowl gasket.

 

[evmini]

if i try that and it doesent work what does that mean is wrong?

 

[Blaaster]

If the fuel is above or below the specified point the float will have to be adjusted.

To check for an unrestricted flow of fuel, place the drain tube in a container and check for a constant uninterrupted dribble of fuel from the drain.

 

[evmini]

i did the test and the gas was perfect on the line with the carb in the tube im not sure what else to check for

 

[Blaaster]

Methinks you should talk to Awk about a leak tester.

 

[evmini]

i was looking over the blaster and the carb boot has some cracks that gas leaks threw could this cause the problem ?

 

[JBRoc01blaster]

That's a major air leak, and that will cause much greater problems than the sputter you mentioned. Unless you want to fry your piston I wouldnt even start your blaster until you buy a new boot, then take blaaster's advice and contact Awk for a leak tester ... And hope that serious damage hasn't already by done !

 

[Blaaster]

i was looking over the blaster and the carb boot has some cracks that gas leaks threw could this cause the problem ?

Oh yes, ooh, yes, ooh yes, a contributor of a major air leak.