Pat G., I'll measure and get back to you. Also you mean diameter, right? Most filters on the market for motorized bicycles are setup for the nt carb. Some are made for the dellorto clone carb.

Bicycle Motorsports yes the diameter. Thanks.

Pat G., 48mm

hey I drilled a few holes in my stock filter cap check it out kzfaq.info/get/bejne/bKpmo7KQv7rYdXk.html

Desirey & Taylor Channel, what jet size were you at and what size are you at now? You may be running a little lean. What notch on the needle are you on? What fuel ratio do you use? Also what spark plug are you using? I recommend an NGK B8HS (cooler spark). These motors do tend to get fairly hot. That's the nature of them. You can purchase inexpensively, an infared thermometer from Lowes, Home Depot, Amazon and point it at the spark plug boot for the most accurate reading. It should never exceed 190°f max after riding for a while. I usually average ~165°F. Typically as you add better exhaust and intake parts ie. filters, case reed induction, smaller cc cylinder heads for better compression, and other performance parts you will want you jet up to a 75, 80, 85 as the engine will have better flow of air and require more fuel to facilitate that flow of air. If I remember correctly with the NT carb (now using Mikuni VM18), you want to be at a *#65 with all stock parts.* One other thing to remember is that elevation will also play a role in how you jet. The best thing to do, is try various jet sizes until the motor runs smooth with no sputtering or 4 stroking at all throttle ranges. I know it's a bit of a pain in the butt to remove the float bowl and re-jet each time, but it will worth it once you get it right. If you have any other questions, dont hesitate to ask.

Bicycle Motorsports thanks for the info. like your videos well explained and informative i will try all this.. and let you the results.

Desirey & Taylor Channel, thank you for your feedback. I appreciate it. The goal of my channel is to mainly assist people who are new to motorized bicycling. I was new to it at one time and remember all too well the hair pulling, cursing moments trying to get things right. If you have any comments, questions, or suggestions of video tutorials, please leave them in the comment section. I hope it works out. If you're still having trouble, let me know and I'll brainstorm a bit more.

hey check out my new build kzfaq.info/get/bejne/bKpmo7KQv7rYdXk.html

Desirey & Taylor Channel, great job you two! I'm impressed. Your bike looks and sounds great. Keep up the good work.👍If you need any tips or insight, dont hesitate to ask.. Just one small piece of advice. Definitely always *wear a helmet.* There is no margin for error when it comes to safety. You would be quite surprised how often helmets are overlooked by riders.

+Nick V, yes the filter will fit on the carburetor that comes with your particular motor.

Also, my recommendation would be to err on the side of caution with some of those Seeutek motors. The Seeutek PK80 typically has m6 instead of m8 studs (more vulnerable to shear off under high torque). Also it sometimes has phillips head bolts instead of allen (hex) head cap bolts holding the crankcase together.

Found this video of a Seeutek PK80. It illustrates exactly what I'm talking about with this motor. kzfaq.info/get/bejne/jauhorqb3qiUfp8.html

@@BicycleMotorsports video is unplayable

D Cents, I did. Between the two I had on average an increase in top speed by 3 mph. Is basic physics. Think of the motor as air pump. Greater volume of air going in and out = more power. I have a whole new setup with a Mikuni vm18 carburetor and right angle filter by Molassi with a reed valve. I'm putting together a 2nd "motorized bicycle upgrades" video. I'll be uploading soon.

Did you have to re jet the carb? cause i did this and it is getting extremely hot with more air flow

you can but than there will be no air filter.

@@BicycleMotorsports no sponge will stay there

Liam Gallagher, as a matter of fact, yes there is a reason there is no fuel filter. Because if the relatively tight clearance between the carb and the in tank frame, the fuel filter would not fit without raising the fuel hose or causing it to kink. This is okay though because the petcock the screws in the tank has a particulate filter built in to itself. Just unscrew, remove and clean the petcock filter every 3 or 4 tank fill-ups.

Liam Gallagher, the fuel filter unfortunately does not fit properly no matter how I try to install it.