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Scooters - 50cc => Super 8 => Topic started by: Schiben on May 29, 2020, 10:38:06 PM

Title: Ooops - Did I do this wrong
Post by: Schiben on May 29, 2020, 10:38:06 PM

I've had my scooter for almost a year now. I've been lurking since I got it. It's been great! I've done some de-restricting.

I've:

• Removed intake tube (rubber tube that pulls out of the airbox)
  Removed all extra plumbing from the exhaust, except the main exhaust tube itself
  Upsized the jet to an 85
  Installed smooth boss

I'm getting almost 40mph. Pretty happy with the extra midrange punch after the exhaust and jet upsize. However, I just cut the airbox cover port from the round hole to the entire square opening size. I have no power I can barely ride it. It idles fine, but if I go past 1/4 throttle it bogs down. I'm assuming I need to upsize my jet again. The question is, what's a good size to try?

Title: Re: Ooops - Did I do this wrong
Post by: TBR125 on May 29, 2020, 11:23:41 PM

I would say about 2-4 steps up on the main jet for a start. Opening the airflow will require a large up jet. You might need one step on the pilot but up to 5 steps on the main. I would buy an 8 dollar ebay assortment pack of jets to find the general area and then buy the individual jet if you land between 2 jet sizes in the bulk pack.

As an example of the effect of additional airflow, I mounted a uni clamp on foam filter(6"by 3.5") directly to the carb intake on my agility 125 and that took the main jet from a 102 to a 115 even with the stock exhaust.

Title: Re: Ooops - Did I do this wrong
Post by: Schiben on May 30, 2020, 12:21:53 AM

Good info! Thanks.

I considered shimming the needle too. I haven't heard of anyone doing that though.

Title: Re: Ooops - Did I do this wrong
Post by: TBR125 on May 30, 2020, 12:40:38 AM

Glad it helped. Shimming is done I think on the carbs with the sir clips on the needle but my carb had a non-adjustable needle.