Krizyyyy

Hi everyone! Can you use a size 27.5 tire on a size 26 frame, specifically the Giant Aluxx SL Fluidform?

thumpism 

Welcome! 26" is usually a 559mm bead seat diameter and 27.5" is 584mm, so maybe. Depends on brakes, bridges and some other stuff.

Krizyyyy

I have a Shimano SLX M666 brakes, a 3x10 shimano slx groupset, and an Epicon SR Suntour fork. Will it be okay?

Iride01 

Do you mean 26" frame? Or are the existing tires 26"? What is written on the side of the current tires? Even better yet, look for the ISO size stamped or embossed in the rubber. Sometimes it's prominent, most of the time it's the tiny stuff that's hard to read. nnn x nn or nn x nnn sometimes with a c after one of them.

Krizyyyy

I have a size 26" frame, giant aluxx sl fluidform to be exact. My current tires are Kenda Nevegal 26x1.95 . I was wondering if I could switch to 27.5" tires. Will it be possible?

Iride01 

Well you'll have to switch wheels too. 26 x 1.95 is a ISO 26 x 559. So you can only use tires that have a 559 BSD. 27.5 tires are ISO nn x 584. The bead seat diameter will be too big and they'll not even touch your current wheel rims.

If you switch wheels, you'll have to worry about frame clearances and finding hubs that'll work with your disc.

Krizyyyy

I'm planning to change my wheel set but I'm worried if it'll be compatible with my frame. Although my friends told me that it's compatible and it'll be fine.

Iride01 

Well do they your friends have those wheels with the same type disc as your bike? Get them to let you try them on your bike.

Your LBS might be helpful too if they deal in a lot of those type bikes. I'm just a road bike type. So I'm mostly guessing.

Krizyyyy

Got it. Will soon try. Thank you, ride well, and stay safe!
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Russ Roth

That is the only way to know, put the wheel size you want with a tire of similar dimensions and put it on the bike. Don't need brake or gear compatibility since you're just checking for frame clearance. I will guess the answer is no. A lot of 26" bikes didn't make space for bigger since bigger wasn't really used. Typically you can go down a size, up a size is something different.

cpach

Aluxx SL Fluidform is not the model name, but rather indicates its made from aluminum alloy, is "superlight", and has hydroformed tubing.

This is usually a bad idea. The frame is designed around 26 inch wheels, so even if larger wheels fit, the geometry will be whacked out. Specifically, assuming everything actually fits, it'll raise your bottom bracket height making the bike less stable. The one exception is if you're swapping from a smaller wheel with a larger tire to a larger wheel with a smaller tire so that the tire diameter is approximately the same, like going from 29x2.3 to 27.5x3.

If you don't change the fork, it will near certainly bottom out onto the fork crown at full compression. The rear end might have space, but is unlikely.

Don't do it; it is dumb.

crowbike

2001 Homegrown converted to 27.5.

JohnDThompson 

There two issues to be concerned with, and both are specific to your frame, so you'll have to make some measurements or take your chances.

1) Brake reach. "27.5" rims have a wider radius than your current rims. If you have disc brakes, this won't be an issue, but with caliper, cantilever, or linear pull brakes, you'll need to be able to raise the brake pads high enough to reach the rim. You'll need to be able to raise them about 12mm (1/2") for this to work.

2) Frame/fork clearance. The wider radius brings the tire closer to the frame and fork. Too wide a tire may not clear the frame and/or fork. This is trickier to do without having the actual parts in hand because tire profile varies with tire construction and rim width, but if your tires are already close to the frame of fork, that suggests you may have problems with the "27.5" wheels unless you run much narrower tires than you currently use.

Krizyyyy

Thanks for the tips! I'll bring it to the bike shop after the quarantine ends.

wheelreason

Are you sure Capt. Obvious?