Fat cruiser build with Car tires

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NICE!
Do you need the kickstand? Looks like it is standing well on it's own...
 
moleman said:
NICE!
Do you need the kickstand? Looks like it is standing well on it's own...
Click to expand...
Lol yeah it needs it. Probrobly wont have any more progress till next week. but iv been scooting it around the driveway to sorta see how it rides and its pretty cool. its gonna be a fun bike for sure
 
Trust me, You'll have a blast with this beastie!!!
 
I'm no stress engineer, but I think you need to gusset the other tube on the bottom bracket something like you did with the kickstand mount. Amazing work, will keep watching!
 
I might do that even if its just for looks because you are right it just looks weak there. Im probrobly going to tie the two sides together with the lower fender mount so it might not need it but i might as well add it anyway for looks sake.
 
Thanks Ill have to check out your build. wonder if a mod can double post if for me or if I have to start a new one.
I built the crank today. I was going to use 3/4" bar and a pipe to fit over it but i couldnt find a good pipe so i used 5/8" hopefully it wont bend it seems strong enough so ill give it a try. you can see where it bolts together in the center and I drilled an access hole for the socket. the nut is welded on the back.


 
Porsche930dude said:
Thanks Ill have to check out your build. wonder if a mod can double post if for me or if I have to start a new one.
I built the crank today. I was going to use 3/4" bar and a pipe to fit over it but i couldnt find a good pipe so i used 5/8" hopefully it wont bend it seems strong enough so ill give it a try. you can see where it bolts together in the center and I drilled an access hole for the socket. the nut is welded on the back.


Click to expand...
You may want to think about converting this to a three piece crank setup. I think your weak point is going to be right there in the middle. With the three piece crank you could make a standard three piece crank axle long and one solid piece. Then you would either weld a three piece BB shell inside the one piece BB shell or use the adapter cups.

Though you can still see if what you did holds up. Cool idea, I like the way you think.
 
I've ridden several bikes with very fat tires. One use a race car tire about 12" wide. Another used old school atv tires. The profile of the tire makes all the difference in handling. Flat tread is very hard to balance and steer on a 2 wheeler. A round top tire is far easier to ride. Your tires look rather flatish. Over inflating those tires will help the ride.

Regarding your bolt together crank. I recommend a grade 8 bolt. Those are much stronger. Your left leg will be torquing the bolt and pipe addition. A softer steel bolt will bend and then break off. The hole in the pipe will get elongated and your cranks won't stay at 180. This bike will take some serious leg power so you will need a sturdy crank.

Have you tried installing the chainring and right side cone yet? Will they fit over the welded on nut?

Looks like it will be a fun ride.
 
+1 on the grade 8 bolt. You can get one for less than a dollar, and it will last more than a ride or 2.
 
yup I know all about the handling with different tire profiles. Iv been building minibikes for years. These were the best ones I had as far as roundness and i dont want to use motorcycle tires. I think theyll do just fine. As far as the crank bolt grade 5 or grade 8 definatly but I doubt itll break. Isnt the shear strength better on grade 5? Pretty sure iv heard that. I may try and aneal the small side of the crank to prevent bending but its not a stunt machine. im going with low gearing and i only weigh 150. and its not a big deal if it gives me trouble. and the sprocket / nuts dont have to fit over the nut. thats why i put the small shaft on that side of the crank
 
I think a grade 5 will shear later than an 8, but it will bend a lot sooner. The 8 is way stronger before it starts to bend though.

Awesome project! Keep up the good work!
 
Heres another bike im working on. Its been kicking around the garage for like 3 years and i finally got around to painting it. Couldnt decide on the color so I just did it and it ended up green and white to go with the seat. It should look alright. I might have started a thread on it years ago but I dont know if it got wiped out with the forum change. Made the frame from chain as you can see . But the cool part is that you can pedal it backwards for low gear and forward for high gear. I was thinking of putting a bicycle motor on it at first but that probrobly would have taken another 3 years. and the frame is a bit too flexible for that i think. Anyhow im glad its nearly done and out of my way

 
Porsche930dude said:
Heres another bike im working on. Its been kicking around the garage for like 3 years and i finally got around to painting it. Couldnt decide on the color so I just did it and it ended up green and white to go with the seat. It should look alright. I might have started a thread on it years ago but I dont know if it got wiped out with the forum change. Made the frame from chain as you can see . But the cool part is that you can pedal it backwards for low gear and forward for high gear. I was thinking of putting a bicycle motor on it at first but that probrobly would have taken another 3 years. and the frame is a bit too flexible for that i think. Anyhow im glad its nearly done and out of my way

Click to expand...
Nice work! A retro direct chain bike!

Luke.
 
Ok thats what its called Retro direct. I didnt know lol Ill have to remember that when i try to explain it to people
 

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