20 inch bmx

ok so i went out to the garage and got into my engine stuff , found a fuel primer with some fuel line on it so i put it on instead of the silicone tubing and tried to start it up , nothing the fuel tank had paint still in it the gas turned to jelly and clogged the fuel shut off valve. so i took the tank off the bike drained it , and took the valve off , it was filled with black/green sludge i cleaned it out and lathed a small adapter on a dremel for a metal filter type device from my nitro methane engine and the attached picture is the end result
 
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sorry to hear that it got crapped up on you, you have a lot of ingenuity though. I don't know if that will fix the problem or not because in-tank filters have always had the bad habit of clogging when I use them. Good luck though and tell us how it works :)
 
well im cleaning out the tank right now so there "shouldn't" be anything in there , but if there is at least ill have a little warning before it gets in the valve again so im going to test it out again after i finish cleaning the tank .

EDIT: its a tight fit , but it works , when i pulled the filter out it pulled some more gunk out, so im going to get my gun cleaner brush i got and scrub the inside of the tank. I know the engine works and for now im not firing it up again till its mounted to the bike. ill run the stock carb till i can afford the new carb, since all the money is going to the remaining parts: chain sprockets and an all new brake set up which is 110$ mud guards 12$ and metal for the mount 20$ 145$ out of 157$
 
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way to small. i have the bike geared for an 18:33:1 ratio even a 90 tooth cant do that 6 teeth to 24 jackshafted to the right side a 12 to 55 tooth vi have an 80 tooth
 
Vfalpha-1 said:
ok update guys, i clear coated the tank ,....but the @%^#% clear coat ate my pain, though im to blame i grabbed the wrong can , re painted the whole thing from bare metal and now the clear coat is drying. I found an issue with my carb , the cast metal was so weak that it broke off when i tugged on it only just , so i cut a thick washer from stock and made a plug for the carb where the fuel was supposed to enter through. I took my micrometer and measured some parts off of my scrap engines from over the years and found a small spigot and drilled a hole for it to go into , the problem is im using car fuel line, so i had to make an adapter , and i used what i had, rc car parts ,my diabetes test strip vials (type1) solder and anything else i could find , the end result looks like an external fuel pump to make it go ZOOM ZOOM lol but in reality its just a barb with a hole trilled into it with solder plugging it up the black vial was meant to be a second filter but one is good enough, so its now a mini holding canister for whatever. but it looks mean now. and i now have 157 $ to finish my project :) i made a new much more pretty mount . but i had my angles off and i don't wanna cut it up again and redo it so imma' start from scratch again using l stock and whatever metals i have ( i attached a pic of my two guitars with my FUZZ nickname in the special lettering i came up with done with a sharpie)
Click to expand...
i have a squire just like that
 
ok the engine is a pain in the @$$ to start , and wont keep running the coil in the pull start came undone as the engine started :O but it didnt get caught thankfully as i reached for the kill switch. made a new mount. smaller and much easier on the eyes later it will be coated in engine enamel i dont like the carb at all , its a pain , the top peice where the throttle cable goes in is stripped out now the plastic cracked so i melted it back together , it's hard to get the engine to idle let alone start it i messed up my hand trying to start it and i was wearing gloves modded the carb some for easier starting but it will need to be replaced, soim selling my modus hub adapter and my intake from my chengine , which they where never used, both for 50$ shipped . sound reasonable ? as the hub adapter is 55$ and the intake is 20$ its the ported intake. i need to get a new carb and some copper tube to finish the bike , and i will be ordering my sprockets and new brakes tomorrow i hope ,if things go as planned. i will post pictures up later, right now my internet is being annoyingly slow
 
ok so I'm really irritated with this crappy float carb so I'm just going to run the engine with a walbro carb , when i get it i ported the engine for the pulse signal to the carb because the adapter plate that comes wit the new carb will be too short and interfere with the mount unfortunately, but it was simple enough to tap the engine out the choke will be on the left side now instead of the right , so i made a small choke lever on the bike then used a bike spoke as the push rod for the choke , instead of the throttle return spring that is on the carb im taking that off and putting on an oil filled shock from an rc car this wat the tension is adjustable and smooth , it feels so much smoother so i had a few delays but thursday i will be ordering the remaining parts except for the carb as im flat out broke after i order my parts
 
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ok i took a better picture of the tap i put in for the pulse signal. the drill bits i have that where close where only 3.15 mm in diameter (should probably invest in a good drill set) and the little spigot for the tap is 3.93 mm so i used a rotary carbide bit and hand machined the hole to 3.83 mm ( hehe surgeon hands :D ) then pressed the spigot in which took some force, but it went straight in and its not coming back out unless i bolt the engine down and pull really hard, i attached 20 pounds to the spigot and it didn't budge , still I'm going to put some industrial strength epoxy on it
lol my piston shrank in the rain XD there probably wont be much work done on the bike after I order the parts because i need a new carb and i still need copper pipe to finish the exhaust which sucks the carb was a problem i didnt expect to run into , but still , i will get this bike running. I'm making an adapter so the stock carb mount will allow for a walbro style carb instead of the mount that comes with the engine.
 
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Excellent job :D That's true home engineering at work. That's a tiny piston, what sized nitro did that come out of ? :)
 
it came out of a modified .15 which some of the parts i actually used on my pocket bike engine haha i want to get a larger nitro and convert it to gasonline I've seen it done
 
I want to get a bunch of cox baby bees and make a series of the world's smallest lawnmower, chainsaw, weedeater, and leafblower rotfl
 
hahaha that would be great! i'd love to see that. I'm going to get a scrapper engine to experiment with. maybe hydrogen injection with the fuel ive been planning something like that for a year now , but ive been more focused on electric designs than ICE
 
Cool man, yeah, I'd love to do it and get featured in Popular Science's DIY section, it's been a dream of mine for a while :D Hydrogen injection sounds cool, but it might be next to impossible on the glow engines...
 
glow yes but if i converted it to function like a regular gasoline engine it might not be impossable, and i wanna try it with a weedeater motor but im much better with electronic systems so i might just stick to that, im already designing my electric build after this bike im getting 3,000 his summer for robotics so i might get to build it this summer , and a 10 Kw electric bike will smoke alot of things hahah
 
Holy mother of jesus, your bike will weigh like 900lbs after you're done with the batteries :D Still, 10kw is 7.3hp, that's crazy, now THAT I REALLY want to see :)
 
nahh id be using lithium batteries i dont like lead acid , too heavy , everything i build i build light weight just like his bike im working on now , it weighs less than 50 pounds fully loaded and i only weigh 130 so me and the bike weigh less than my best friend and i have mroe than 5 HP with this one i know it will fly but i wont let it because it doesnt have disc brakes , though if I build the stretch cruiser i might still keep it gas powered and retire this bike it just depends on how things go
 
Nice :) Yeah, I weigh 170 so yeah, lol, that's a light vehicle even with you on it :) still, a monster electric is something I'd LOVE to see :)
 
well it depends , because i know the battery system im planning will cost 2,000$ alone and that only leaves 1000$ for the build i want to make it like a chopper style build , i love street bikes because of the way they handle that's why i chose a bmx bike because of the maneuverability but its insanely hard to find 20 inch bmx bike tires with disc brakes so the next build will be a larger 26 inch rimmed bike with disc brakes and fron suspension, the seat will have suspension in the next build and will be a steel framed bike , i plan on keeping the pedals on the next one just in case the engine decides to crap out for some reason
 
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