I was wandering(yes again). On tire profiles... I know the profile is read as 170/80 or 110/80. But does anyone know how much difference there is between sizes? For example: I have a 140/80 for my back tire. I'm changing rims and wanting to go to a 190/50. I know the 190/50 is wider and lower in sidwall height. But how much size difference is their between a 140/80 and a 190/50? I know the profile are measured in the metric scale. But does anyone know the mathmatical mumbo-jumbo in to converting it into to simple measument terms.. as in 140mm wide 80mm sidewall height (I hope I didn't just answer my own question[sm=laughat.gif].)? I'd like to know so I can go out with a tape measure and see what'll fit and what'll hit.

 

no, the sidewall number is a ratio from height to width. and do not put a 190 on there, there so many post why, i'm not gonna go through it again just don't do it.

 

Alright I'll just go with the 180. That's what you got on yours right? I found a rear rim off of a '91 hurricane(5.5inch rim). I gotta wait till tomorrow to get it[:@]. The difference between the 180 and 190 probably isn't much looking at it. But I understand the handling issue. The 190 idea was just for looks. After I think about it the 180 does sound better. It's probably cheaper anyways.
So.... am I right on the 140/80 tire being 140mm wide. I kinda understand car tires. Are bikes the same? A car tire size of 275/85 means the height is 85% of the tread width? I think that's right. If I ain't right I think that'll be three strikes for me tonight and I'll have to stop asking questions. LOL.

 

80 percent of 140 would be your sidewall height i believe. i have a 1990 rim with a 170 rim and tire on it.

 

it is the aspect ratio of a tire. for example a 140/80 means the tread is 140mm wide and the sidewall is 112mm tall. hopefully this helped out. happy hunting for the new tire

 

If you have earlier model of hurricane, you woun't be able to put 180 tire, the rim is too narrow. Note that

 

he is going to the later model rim

 

I thought it worked like the distance on the left and across the bottom... by sidewall, does old1000 mean the distance shown on the right?

Now I'm wondering if there is any measurement for the radius of the tread? I suppose wider tyres with lower profiles will be flatter (bigger tread radius) but maybe the tread isn't always circular, maybe the curve gets tighter towards the edge of the tread?

The 5.5" rim width is right though hey?



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