Author Topic: Widest tire possible and fit for riding for an 18 x 1.85 rear rim?  (Read 8854 times)

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Offline cocinero196

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Any thoughts on the widest tire possible and fit for riding for an 18 x 1.85 rear rim? ;D
Will a 4.5 x 18 or a 120 x 18 tire still be okay for the 1.85 rim width?

Offline calj737

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Re: Widest tire possible and fit for riding for an 18 x 1.85 rear rim?
« Reply #1 on: February 05, 2016, 05:15:33 am »
120 is pretty wide depending upon the aspect ratio. Best to stick with a 110 or 4.10.
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Offline cocinero196

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Re: Widest tire possible and fit for riding for an 18 x 1.85 rear rim?
« Reply #2 on: February 05, 2016, 07:04:42 am »
120 is pretty wide depending upon the aspect ratio. Best to stick with a 110 or 4.10.

Thanks! I really wanted the look of the 120 though >:(

Offline 70CB750

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Re: Widest tire possible and fit for riding for an 18 x 1.85 rear rim?
« Reply #3 on: February 05, 2016, 07:15:58 am »
120 is pretty wide depending upon the aspect ratio. Best to stick with a 110 or 4.10.

Thanks! I really wanted the look of the 120 though >:(

The look helps very little in tight corners  ;)

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Offline wowbagger

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Re: Widest tire possible and fit for riding for an 18 x 1.85 rear rim?
« Reply #4 on: February 05, 2016, 07:18:33 am »
This does not take bike geometry or handling into account but it tells you what tire sizes can be installed on what rims widths:


Offline CBGhia

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Re: Widest tire possible and fit for riding for an 18 x 1.85 rear rim?
« Reply #5 on: February 05, 2016, 07:24:05 am »
yeah, the 100 should be the right size for that skinny little guy.

Edit:   Sorry, I was wrong.  110 is what I run on my 550 and I guess it has the same size rim. I put a 120 on there once and the handling really suffered.
« Last Edit: February 05, 2016, 10:35:55 am by CBGhia »
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Offline Powderman

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Re: Widest tire possible and fit for riding for an 18 x 1.85 rear rim?
« Reply #6 on: February 05, 2016, 08:57:36 am »
Will it fit, yes. Will it detract from the handling characteristics, yes. fitting a tire that wide on a skinny rim will pinch the side walls giving the tire more crown that if it were mounted on a proper size rim. I would not recommend a tire that big on that rim if I planned on actually riding the bike.

Offline Old Moe Toe

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Re: Widest tire possible and fit for riding for an 18 x 1.85 rear rim?
« Reply #7 on: February 05, 2016, 06:36:18 pm »
If you MUST have a fatter back tire you can lace up a K7 (17inch) rear rim to your hub and put on a 130mm wide tire. I did that on my K2 and am very happy with it. The overall outside diameter of the tire was within a millimeter or 2 of the original 100mm wide tire. Only thing I had to do was cut a small section out of the chain guard to stop the wider tire rubbing.

Offline cocinero196

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Re: Widest tire possible and fit for riding for an 18 x 1.85 rear rim?
« Reply #8 on: February 05, 2016, 09:40:27 pm »

Thanks guys! Will just probably get a wider rim to accommodate the fatter tire ;D
I'd like to stick to size 18, will 2.15 be okay for a 120 tire?

Offline turboed13b

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Re: Widest tire possible and fit for riding for an 18 x 1.85 rear rim?
« Reply #9 on: February 05, 2016, 10:38:18 pm »
I went from a 110 to a 120 unless you are pushing hard into the corners and dragging knee you won't notice a difference.

Offline cocinero196

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Re: Widest tire possible and fit for riding for an 18 x 1.85 rear rim?
« Reply #10 on: February 06, 2016, 02:27:22 am »
I went from a 110 to a 120 unless you are pushing hard into the corners and dragging knee you won't notice a difference.

What was the size of your rim?

Offline calj737

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Re: Widest tire possible and fit for riding for an 18 x 1.85 rear rim?
« Reply #11 on: February 06, 2016, 02:43:47 am »
I'd like to stick to size 18, will 2.15 be okay for a 120 tire?
I'd bump to a 2.5". There's no clearance problems with that rim, and it will support the 120 tire perfectly.
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Offline cocinero196

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Re: Widest tire possible and fit for riding for an 18 x 1.85 rear rim?
« Reply #12 on: February 06, 2016, 06:19:42 am »
I'd like to stick to size 18, will 2.15 be okay for a 120 tire?
I'd bump to a 2.5". There's no clearance problems with that rim, and it will support the 120 tire perfectly.

Got it! ;) but I would still have to get a 40 spoke rim for the oem hub to match right?
Thanks, cal! Will be bugging you soon if I pull the trigger on an M-unit ;D
« Last Edit: February 06, 2016, 06:28:40 am by cocinero196 »

Offline turboed13b

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Re: Widest tire possible and fit for riding for an 18 x 1.85 rear rim?
« Reply #13 on: February 06, 2016, 06:21:33 am »
I went from a 110 to a 120 unless you are pushing hard into the corners and dragging knee you won't notice a difference.

What was the size of your rim?

1.85 I am moving tona 2.15 here soon.