Can I fit 20inch wheel into a frame designed for 18inch?
02-02-23, 01:03 AM
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Can I fit 20inch wheel into a frame designed for 18inch?
Currently sporting an 18inch wheel, I have 5cm/2inch of space/clearence from the frame, measured from rim (without a tire on). Right now I am using a schwalbe kojak 18x1.25 inch tire.
02-02-23, 07:15 AM
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What ISO sizes are we talking about? 349 to 406? Probably not. 400 to 406? most likely yes. Is there also an issue whether the brakes will line up with a new rim?
02-02-23, 08:21 AM
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Brakes shouldn't be an issue if that is a disc brake in the photo?
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02-02-23, 08:26 AM
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Currently you don't appear to be running Any tire.
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02-02-23, 08:57 AM
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Distance without the tire in place does not help. How much space is there between the tire and frame at the closest point?
You can use this information to see exactly how much difference there is between your 18" rim and either a ISO 406 or 451 rim https://www.sheldonbrown.com/rim-sizing.html The only 18" wheel that might be the one you have is the ISO 355 rim "used on Birdy folding bikes". A rough calculation between the 355 and 406 seems to mean the larger diameter tire would be an inch closer to the frame if you used the same brand and model tire.
Somebody asked a similar question about tire size on a recumbent but failed to say that he was using fenders. While the tire would fit if there were no fenders, the closest point was not the frame but the fender.
You can use this information to see exactly how much difference there is between your 18" rim and either a ISO 406 or 451 rim https://www.sheldonbrown.com/rim-sizing.html The only 18" wheel that might be the one you have is the ISO 355 rim "used on Birdy folding bikes". A rough calculation between the 355 and 406 seems to mean the larger diameter tire would be an inch closer to the frame if you used the same brand and model tire.
Somebody asked a similar question about tire size on a recumbent but failed to say that he was using fenders. While the tire would fit if there were no fenders, the closest point was not the frame but the fender.
02-02-23, 10:09 AM
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Mont a tire and measure your clearance. Without a tire in place there is no way anyone can comment beyond the notes about rim ETRO sizes. You can put a bigger tire on the smaller rim and a smaller tire on the bigger rim. Wheel size and frame clearance are all in the context of tire size.
02-02-23, 03:09 PM
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I don't know why you would aside from making whatever mega odd ball project thing even more odd ball. Really the only time I would actually switch wheels sizes is to go smaller so I could cram a wider tire in it. I get that 18" is a very weird size and not really existent outside of maybe some wally-mart junk and cool things like the R+M Birdy which are still odd. But so long as Schwalbe still makes tires for them I wouldn't change.
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02-10-23, 06:27 AM
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tire options are good for 18inch wheel, it gets worse with rim options. i found 36H 18 inch rim from only strida folding bike and the other 18 inch rims available were from some chinese seller on aliexpress and i do not trust those. 3cm of space with tire on availabe, which is 1.18 inches. I was just asking in case I wont be able to find 18 inch rim after I damage my current one.
02-10-23, 07:48 AM
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As others have mentioned, frame clearance depends on rim+tire.
