Beta Riders Club Discussion Forum

If you only have the stock needles, then I would go 38pj, 168mj, N2ZW at clip 3, with air screw 1.5 turns out as a starting point...but that’s just me. Opinions will differ. The most important thing is to learn as much as you can and apply it to your bike. Here is a link to a carb tuning guide that I found very helpful https://www.duncanracing.com/TechCenter/KeihinCarbJetting.pdf, and the people on this forum are great so don’t hesitate to ask. Start ordering different size pilot jets, main jets, and needles because you will need to change them up as temps change. Also, keep on top of your oil injection system. If that fails, very bad things happen

Literally just got home with a NEW to me 2013 Beta 300rr with 30 Original hours. Thing is super Rich on bottom.
Previous owner left it completely stock and fuel is old @ 50:1 which I don’t prefer either. I’m hoping these Beta’s can be cleaned up. Lot of “jetting threads”...
Wish me luck. Ha

Ghost

Hello, need some help again..
in lower temperature my bike worked fine, now it is quite hotter out, like 30C and the bike have some problem in 1/4-1/2 throttle, when/while PV is opening. Sounds like choke on. It is just for a small part of the power band and just if i am slow on the throttle, or if a im holding it in this point while accelerating. Then in higher rpm is ok again.
Now:
When AS is at 1-1/4 turn out, then idle feels/sound ok - but i have problem described higher
When i go wit AS to 1-1/2 or more out, then idle sounds like lean, but my problem is solved.
When i go with AS more than 1-1/2out, then idle is hanging = definitely to lean.

Should i move needle to leaner side ?

I do not now what for jetting is inside, but it was working properly in lower temp.
Starting is ok, WOT is ok.
When bike is very hot, after 20min. on motocross track, works fine, but on single trail its problematic..

.. its interesting, how the sound of the bike change with just AS setting, specially if you are on higher gear and rpm and you just hold the throttle open little / under PV open point..

did you change your jets for summer temps?

Elevation?
Jets?
Needle and clip position?
Premix or oil injection?
Spark plug?

SamanBN wrote:Hello, need some help again..
in lower temperature my bike worked fine, now it is quite hotter out, like 30C and the bike have some problem in 1/4-1/2 throttle, when/while PV is opening. Sounds like choke on. It is just for a small part of the power band and just if i am slow on the throttle, or if a im holding it in this point while accelerating. Then in higher rpm is ok again.
Now:
When AS is at 1-1/4 turn out, then idle feels/sound ok - but i have problem described higher
When i go wit AS to 1-1/2 or more out, then idle sounds like lean, but my problem is solved.
When i go with AS more than 1-1/2out, then idle is hanging = definitely to lean.

Should i move needle to leaner side ?

I do not now what for jetting is inside, but it was working properly in lower temp.
Starting is ok, WOT is ok.
When bike is very hot, after 20min. on motocross track, works fine, but on single trail its problematic..

.. its interesting, how the sound of the bike change with just AS setting, specially if you are on higher gear and rpm and you just hold the throttle open little / under PV open point..

The hotter weather (all other things relatively equal) would richen your mixture. As it gets hotter, the air is thinner. Therefore, you should use smaller jets & possiblyadjust your needle. Its all in the manual.

SamanBN wrote:Hello, need some help again..
in lower temperature my bike worked fine, now it is quite hotter out, like 30C and the bike have some problem in 1/4-1/2 throttle, when/while PV is opening. Sounds like choke on. It is just for a small part of the power band and just if i am slow on the throttle, or if a im holding it in this point while accelerating. Then in higher rpm is ok again.
Now:
When AS is at 1-1/4 turn out, then idle feels/sound ok - but i have problem described higher
When i go wit AS to 1-1/2 or more out, then idle sounds like lean, but my problem is solved.
When i go with AS more than 1-1/2out, then idle is hanging = definitely to lean.

Should i move needle to leaner side ?

I do not now what for jetting is inside, but it was working properly in lower temp.
Starting is ok, WOT is ok.
When bike is very hot, after 20min. on motocross track, works fine, but on single trail its problematic..

.. its interesting, how the sound of the bike change with just AS setting, specially if you are on higher gear and rpm and you just hold the throttle open little / under PV open point..

I'd imagine keeping your air screw at the setting you like now, and then just dropping the needle 1 clip, would clean things up and make the bike run like it did in the cooler temps.

Definitely i must open it today and look what inside.Im second owner, so who now..
I did not change anything /in low temp worked great/, so it must be stock.
Elevation is 300-1000m. It is RR300/2017, aprox. 100 hours..

If i open it, first i try to move the Needle one clip.

but it looks i need leaner N2ZJ needle and maybe main jet.
I can buy N2ZJ and others needles from KTM dealer for 8Euro each, its cheap experiment..

Thanks, i will reply how it worked !

I checked it today and it was stock (grey) setting in table = 38, 165, 1.25, n2zw, but needle at pos. 3

I movee the needle to pos.2 fron top =leaner, and it looks much much better, maybe it can be thick better with another needle, but its ok for the temp wehere im riding... compromis for whole year.

Wow thats power and acceler. now

Thanks !!

what is richer a higher letter eg n2zw is n2zh is it leaner needle jet .on the beta riders form has put in necj needle jet in carb on beta 300rr or 300rr racing

Yes, N2ZH is more rich than N2ZW