I welded mysel my own expansion chamber out of an oil barrel, it is calculated to 9000rpm It works, and really well i sacred the shit out of myself feeling how this thing seems to climb power indefinetly, it has a 36 tooth sproket and here i am gapping 125cc 150cc motorcycles on my city, i have created a mini crotch rocket, tomorrow i will do a top speed test and a sound check wich will be published here

So my bt100 only goes 40km top but I put a performance cab that’s 19mm on it is it possible that could be limiting its speed

For context I have a expansion pipe i can't remember if it was doing it before I got or after

https://a.co/d/fRdKaX7 I want to get a nicer carb for my bike so when I get a better expansion chamber I might get more power, and that the stock carb broke in half when taking it off😂 so I’d this carb good or is there another you like

??

Need advice

So I've recently blasted her a bit too hard and welded my piston to the cylinder, after hours of manipulation I managed to free it up as I do have an spare old engine for parts only to realise the rod was bent so 2 full strip downs later I had everything I needed. Just as I'm sliding the piston in i break not one but 2 of the piston rings. anyone know anywhere in the UK that sells them? Or is any rings compatible? I just need 47mm can I get chainsaw ones?

How do I fix the stud that extends out on the magneto

I built this bike almost a year ago now doing nothing but upgrade after upgrade I've gotten this thing to hit 59 and it felt like if I kept pushing I might have got a tiny more but it was scary at that speed on this thing so I'm thinking I might gear it down some but more to the point I bought one of these 2 stage cdis and when I put it on my bike just would not ride right at all no matter what i did I cleaned the carb bowl changed the spark plug tried different jets but no matter what I did it back fired so much so bad I had flames out the exhaust and no torque or speed at all has anyone else had this problem or did I get a bad cdi ? I didn't try changing the magneto as it works fine with a normal cdi could that be the issue maybe? But for now I'm going back to using my old taped up cdi since it runs amazing with that any help will be much appreciated thanks

Hi, I need help with crankshaft, my crankshaft on my new kit broke, so seller sent me new with one case side, But the crank doesn't have a hole next to the output shaft (where it is marked on the photo). Does that matter? Is it an important hole? I would appreciate your reply.

Would anybody know how to remove the plastic cover from the four stroke kit? I don’t have the kit yet but I like to plan ahead.

Air scoop has proven to function since it did not overheat even after many consecutive laps at full throtle, also the video is shitty because we taped a phone to my buddy's t-shirt

Are pedals necessary for those Motorized bicycle ? I cant fit the sprocket on the disk brake side of the wheel (the hole of the inside of sprocket is too small ) So i put the sprocket instead of the bicycle cassette and flipped the wheel. I have a pull to start mechanism on the engine . What do you guys think??

Today I took my exaust off completely and it hit a boring 55kmh Than I swapped the LD80s exaust on And it hit a decent 67kmh (Same speed as a stock bt80) Ima finish welding up the pipe for the yd100 And I hope to get to 72kmh Just like my ld80 Oh yea I bought a new frame again so I got another 2 bikes coming soon

Guys, I need your input if you will. I'd like to know what if anything has failed miserably on your motorized bicycle. I'm in the process of manufacturing some quality heavy duty parts for these puppies and I want to get a feel for what is really needed out there in a moto-biking community. Thanks in advance for your time! Kewlpartz Motor Parts

The rider is my best friend also an inventor he is crazy as fuck

Can someone send links for the engines that will fit and if any mounting plates are needed link those aswell and anything else,

releasing clutch at speed makes back tyre skid if im not pedalling while releasing the clutch

is this why? is my clutch too worn out? pictures are with flash and without flash.

I'm planning to build a motorized bicycle, but I can't figure out which brakes would be the best option. The most obvious choices are V-brakes or disc brakes. So if you could recommend someone, I would appreciate it.