Will a motorcycle fender fit over 26x4 fat bike tires?

[PartsBuyer]

I want to put a nice fenders on a fat tire bike. I'm looking at some Royal Enfield 500cc Bullet Classic rear fenders because they appear to have a lot of clearance over the 120/80-18 tire and look slim enough to work into the fat tire bike frame. Does anyone know if 26x4.0 tires would fit or know of another cycle that would?

 

[PartsBuyer]

Width is fine. It's the arc I'm concerned with. At worst I figure I would cut a few inches off one end and/or lift it higher?
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[Captain Awesome]

Width is fine. It's the arc I'm concerned with. At worst I figure I would cut a few inches off one end and/or lift it higher?
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That was going to be my question as well. Does the radius match

 

[Chad T]

Looks like a 120/80/18 tire OD is around 25.5 and lots of clearance on the rear so maybe? Wasn’t able to find the actual OD of a 26x4 fat bike tire.

 

[PartsBuyer]

26+(4.0 x 2) wheel/tire = 34OD/106.8cir/17rad

 

[Wildcat]

My 26 x 4.0 tires are exactly 30" diameter. I just measured again to be sure.

I thoght about using motorcycle fenders also, and I can get motorcycle fenders cheap, but all I've seen so far aren't big enough.

 

[PartsBuyer]

My 26 x 4.0 tires are exactly 30" diameter. I just measured again to be sure.
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I thoght about using motorcycle fenders also, and I can get motorcycle fenders cheap, but all I've seen so far aren't big enough.

Thank you. I guess I'm not using those measurements correctly? Super helpful knowing you haven't found one either. Have you considered or tried losing some length or would the arc just look too incongruent floating above the wheel?

 

[PartsBuyer]

have you tried these shorter and wider fenders @Wildcat ? I know the arc is still incorrect but figured I could cut some space out under the hinge-point.

 

[DesmoDog]

I don't know if these will help, but here are a couple shots of fenders for an 18" motorcycle wheel tossed onto a 26" Typhoon. They wouldn't fit in the frame and these tires are smaller of course but might give you some idea of what the radius looks like.

They have some tubing under them to hold them up off the tire, but that means they rotated down against the tire lower down.

 

[Wildcat]

It will depend on how the fender follows the curve of the big tire. I may get some stainless sheeting and make some.

 

[BobbyStillz]

Width is fine. It's the arc I'm concerned with. At worst I figure I would cut a few inches off one end and/or lift it higher?
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If you don't already know, motorcycle tire size goes by inner diameter, whereas bicycle tire size goes by outer diameter. For instance, a 16" motorcycle tire will fit a 20" bicycle rim. This may effect your calculations.

 

[Wildcat]

If you don't already know, motorcycle tire size goes by inner diameter, whereas bicycle tire size goes by outer diameter.

Concur! A standard 26" rim is 22" in diameter. If the sidewalls are 4" then total height or diameter is 30". A normal 26 x 2.125 tire has about 2" sidewall, making it 26" total.
A 26 x 1 3/8ths rim is taller, that's why the skinny tire still has 26" of height with 1 1/2" sidewalls.

 

[MattiThundrrr]

Something I just remembered from the motorcycle forums... The chopper guys would sometimes make a motorcycle fender out of trailer fenders. They'd definitely be cheaper, probably more readily available too. Used ones from a junk trailer could be reworked in quicker time than fabbing from scratch

 

[PartsBuyer]

Something I just remembered from the motorcycle forums... The chopper guys would sometimes make a motorcycle fender out of trailer fenders. They'd definitely be cheaper, probably more readily available too. Used ones from a junk trailer could be reworked in quicker time than fabbing from scratch

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Thanks! I appreciate having a new set of options to consider. I could see those hatched ones cut to width.

 

[us56456712]

26+(4.0 x 2) wheel/tire = 34OD/106.8cir/17rad

It will look bad if the radius is off.

 

[Slow-Rider]

 

[Slow-Rider]

 

[Slow-Rider]

 

[Slow-Rider]

yes they can be made to fit. just depends on the work you put in to make them fit.

 

[Da Gas Man]

yes they can be made to fit. just depends on the work you put in to make them fit.

.... and the tooling .