Should i change carbs ?

The carb on my stock qt50 has had too much tinkering with before i got it .i have decided to either buy new stock replacement or go with something that might work better ..i have seen some posts about running 15:15 sha on these .question is to those that have swaped if it is basicly plug and play or do i need to get other parts to make the change over before i order one..thanks in advance for any info on this

Re: Should i change carbs ?

> Pops Peds Wrote:

> -------------------------------------------------------

> The carb on my stock qt50 has had too much tinkering with before i got

> it .i have decided to either buy new stock replacement or go with

> something that might work better ..i have seen some posts about running

> 15:15 sha on these .question is to those that have swaped if it is

> basicly plug and play or do i need to get other parts to make the change

> over before i order one..thanks in advance for any info on this

Same carb you would swap jets over and be okay. New carb you would have to tune it because the bike is now pulling in more air. If you can tune a bike, go bigger. If not get a direct replacement.

You will say ....what jet do I need for a bigger carb. The answer is idk? Every bike is different. So if you know a little about tuning a bike swap the carb. If not, get the same as the original. (edited)

Re: Should i change carbs ?

Not that i am any expert on it but i think i took apart my first carb around 64 or 5 years ago and have done mechanic work most of my life in some way..i knew i would have to get it jetted for the motor but was't sure about the hook up and if i will need anything different to hook it up so i can order it all at one time.the carb on it now is not past using but just one that has seen it's better days so i am just mulling over changing .don't take what i am typing as me not appreciating your post .i really do thank you for the info but just wanted you to know i'm not a newbie at tuneing carbs..been a awhile but used to rejet race cars for different tracks,weather condition and on occasion some tracks where we had to weigh more or less ...thanks again

Re: Should i change carbs ?

I've replaced several carbs on my collection of QTs and have just bought the clone bolt on carbs. I take the main and pilot jets out of the original Yamaha carb and install them in the clone. That's if all the jets aren't seized in.! Quick and easy to tune.

Re: Should i change carbs ?

I did not know and now I do. Idk if it is a direct bolt on to the intake or you have to get a different intake. I am sure someone with more QT knowledge will chime in. But if your not adding a pipe I would run a stock replacement. But if you want run a 15:15. Check the intake size and see if you can get the right shim. I am not sure of the QT intakes by no means. But if you get the 15 just get get a range of jets and I am sure you will get it right.

Re: Should i change carbs ?

Thanks guys..the carb i have now was apart and in a box when i got the qt .i have it running decent for the most part but just not happy with it .it does fine one day and starts running like mel tillis talks on others..i thought to start it was the cdi but switched off one from a running ped and still had the problem.then switched the carb off a towney and all is well so just think i am snake bit on that carb.i have been reading some in the wiki and saw some were running the sha so thought it might be an improvement.i grew up bored with the word "stock" so most anything gets improved if i can figure a way.i even put my grandsons 12v electric jeep on 18v,changed the gears from an electric motorcyle and made him the fastest kid on the block..would have my exmark on nitrous but my wife won't let ..lol..thanks

Re: Should i change carbs ?

Jack Rutherford /

SHA clone will work just fine. It should take a smaller main jet than the stock carb since it is a bigger carb/venturi. SHA jets or qt main jets will work in the SHA clone. There's at least one clone, I believe it is the DAKAR clone that has an air/fuel mixture screw as well as the throttle stop screw. This is nice compared to regular SHA carbs.

The SHA carb will fit right over the stock intake. You will need an o-ring between the intake and where it fits into the carb. Go to the hardware store and get one if necessary.

Stock throttle cable should work fine with the SHA carb although double check and make sure the stock throttle cable pulls the slide all the way up. Oh yeah, I've always had to take the brass adjuster that fits on the chamber cap off the stock qt carb and put it in the SHA carb to get the throttle cable length right. The metal cable tube/guide that comes with the SHA is way too long.

You will need a 60mm air filter for that carb. I've bought the absolute cheapest SHA clones and run several on several qt50s. Amazon had some with air filter for $17 shipped. Never had any issues. (edited)

Re: Should i change carbs ?

Jack that was the info i was looking for ..i read a post somewhere that said switching the cable.on the throttle junction box where the oil injector cable connects will give enough cable length also..have you tried that ? I think i will order one and if it doesn't work out like i want i have a garelli it will work on..thanks again to all of you for the info (edited)

Re: Should i change carbs ?

Jack Rutherford /

If you mean using the cable that runs from the junction box to the oil pump then yes, that will work, however, you will have more than enough cable and will have to shim it a bit. I just did this on my vm18 because the slide wasn't being pulled all the way up.

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