Severely bent bike seat post???

unoahguy

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Apr 15, 2020
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unohaguy rides a Whizzer Motorbike, he ain't gonna switch frames.
While I guess frame size might matter. A bent seat post is just a crappy steel seat post. I used to bend seatposts as a kid BMX riding.
Now I weight 2 times as much and a Chromoly laid back seatpost don't bend. But the frame side rails cracked by the seatpost and I had to Welderup. A laid back seatpost puts more stress on the frame. But it took 13 years and 33,333 miles until my frame cracked.
What size post do you recommend? I got a 25.4 mm and it does not fit at all!
 


unoahguy

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Apr 15, 2020
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Whizzer takes 25.4 mm or 1" as far as I know. What size is your old bent seatpost? measure it
I used calipers. It was 25.4 mm (it was severely sanded down, probs why it broke). However, when I measured the inside of the frame, it was 24.7 mm. I called Quenton and he said it might be a manufacturing error. I'm working with a local bike shop to get me a correctly sized post.
 

Wrench

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I used calipers. It was 25.4 mm (it was severely sanded down, probs why it broke). However, when I measured the inside of the frame, it was 24.7 mm. I called Quenton and he said it might be a manufacturing error. I'm working with a local bike shop to get me a correctly sized post.
That's really odd, Did ya try to spread the frame seatpost clamp and top of seatpost tube a little.
Use the top of the seatpost and see if ya can kinda spread the clamp and top of tube area.
It's under 0.70mm That's really close, It seems to me the seatpost clamp and frame tube top have bee squished a little and is out of round. Before ya put a new seatpost in, spray a little WD-40 in the frame seatpost tube. It's gonna be tight.

Before ya waist your money on having a special seatpost made. Take it all to a bike shop and see what they think, I cant believe the frame seatpost tube is too small.
DSCF2090.JPG
 

Wrench

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I reread your post I see your working with a bike shop I'm sure they will straighten the seatpost hole.
 

Wrench

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Try straighten the frame seatpost hole with the old seatpost so ya don't scratch up the new one
 

Wrench

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There's one more thing I can think of that might be a factory mistake.
I know the seatpost clamp is welded on the frame. I was wondering if the seatpost clamp has a small lip on it which would make the inside dia. smaller than 25.4 If so I would file the Lip off the inside of the seatpost clamp to be even with the inside of the frame tube.
 

Wrench

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C.A.O.S. Crankcase Air Oil Separator
Have you put a breather on your crankcase vent hose yet? Is you crankcase vent hose spitting oil?
About the easiest thing to do would be to buy The Big Breather from Whizzer Paul @ www.whizzercruiserparts.com but it's big as a coke can.
Quenton has designed a couple breathers that can be strapped to your bike. The Big Rubber Hose and the PVC Life Support breather
I also have designed a breather that actually is the seatpost. The C.A.O.S. Seatpost Breather. I still have one left for sale.

 
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