Air filter problem? In 2 minds and main jet?

Hi guys,

I have a Pulse Adrenaline 2013 and have just recently bought a 42mm sports air filter. I'm just wondering how do I fit it?

Since the Pulse doesn't have a 'proper' air filter and just has a air box instead?

I know I sound like a complete and utter 'noob' but I have no idea how people fit the cone air filter and need help!

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Also I am in 2 minds to get a bigger rear sprocket or a smaller, either to add some more torque or to get better top end, which would you guys choose? I know that if I choose better torque I would lose some top end and only being a 125 don't think it's a very good choice but I just want to be able to get that front wheel up easier!

The pulse is pretty slow of the line unless I obviously give it a lot of revs and just dump the clutch so I am really struggling to make my mind up!

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The Pulse has a 95 main jet, just recently bought a 105 as that is the most common jet size people seem to change with the pulse, asked a friend to change it for me as he did a motorcycle course in college and seems to know quite a lot about motorcycle maintenance and things but he won't touch my carb for some reason! Just wondering how easy would it be to change the main jet or would it be better to take it to the motorcycle mechanic around my area for him to do?

1st, air box is proper filter. Just not in conical shape. If you insist on fitting a conical filter for some reason, your best bet is to remove the air box and slip it directly on the carb infold. Pit bikes usually have this configuration, e.g.:
http://i00.i.aliimg.com/wsphoto/v0/8...it-b-font-.jpg

Probably you can get similar (if not better) result if you cut some part of the box (somewhere BEFORE the filter) in order to allow bigger airflow through the standard filter.

If you want to wheelie easier, the only way is to fit bigger rear sprocket or smaller front one. This will hurt your top speed though.

In order to change the main jet, you need to take off the cup at the bottom of the carburetor - see the picture above. Most probably you'll have to take the carburetor out of the bike to do that. But, sometimes there is enough room to just tilt it on it's side so that you can access the 3 or 4 bolts that hold it.

Once the cup if off, the main jet should be more or less in the center of the carburetor:
http://www.v-performance.com/content...118_1_text.jpg

Usually it takes a screwdriver to turn it, so take it out and screw in the new one. Put back the cup and the carburetor.

Hints:
i) at the bottom of the cup there should be a big cap (with a hex head usually) which you can take out in order to drain the gas from the cup before removing it;
ii) while the cup is out, check it's bottom for dirt and clean it. Usually this is what gets the jets clogged;
iii) when removing the cup and putting it back in, be careful with the floats (the black, bulky, plastic things on the picture above) ant the needle attached to it. In most cases, there is only one position the cup can go and it's determined by the overflow tube:
http://i140.photobucket.com/albums/r...DSC03269-2.jpg

iiii) do not overtighten the main jet as it's brass and can be damaged easily.

Thanks for the info, it was much appreciated and in depth