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Discussion Starter #1 (Edited)
ND4's Throttle body mod.

Alright all, I am in the process of doing a port polish and performance upgrade on my grom (new head etc). I was going to put this in my build thread but i felt it could be applied to anyone so I will separate it out.

When I was taking things apart i noticed that the throttle body in the stock form had HUGE screw heads and excess screw holding the throttle plate onto the main shaft (relative to the small 24mm opening of the TB). Talk about some nasty airflow path.

IMG_20171111_134534972.jpg

So, some stainless tapered head m3 screws (not pictured), a countersink bit, and some filing of the screws.....


IMG_20171112_135832228.jpg

And you get this, A much better path for the airflow to go through the TB!

IMG_20171112_142528508.jpg

Also while i was there i smoothed out the front edge of the TB itself.

IMG_20171112_155137696.jpg


Just make sure to use some red loctite on the screws when you re-assemble


(WATCH OUT!!!!, when you pull the throttle plate shaft out there are 3 lil seals. 2 on the Cam side that you dont really have to worry about, but the one on the TPS side has to pass through the main TB opening, and the way they are oriented its you have to be very careful when you pull it through the other side of the TB opening. If you do this pull it slowly out and you will see what i mean when you get "stuck" when the seal hits the inner part of the TB opening. You will have to use a little screw driver to push the outer lip of the seal down in the shaft hole so it slides out without destroying the seal)
 

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I do this to stock Ruckus carbs and even go a little bit further in cutting off the the screw head side of the throttle shaft so that the screw goes through the throttle plate and the threaded part of the shaft. On the ruckus it makes a tremendous difference when dealing with such a small port
 

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Discussion Starter #5
I do this to stock Ruckus carbs and even go a little bit further in cutting off the the screw head side of the throttle shaft so that the screw goes through the throttle plate and the threaded part of the shaft. On the ruckus it makes a tremendous difference when dealing with such a small port

Ah i see what you are getting at. I could of done that but naw, counter sunk screw is good enough for me. I also rounded the leading edge of the throttle shaft so its not as sharp as well.
 
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