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Discussion Starter · #1 ·
I Have a 06 Bonnie Black. I.m slowly getting to the Mods this Year with M Bars Nap mirrors Uni Filter , No snorkel and De Baffle completed.

I don't understand the Tire numbers. I get the last being the Rim dia
I would like to change tires to something fatter.

What is the max size width tire I can put on the stock rims
and what is a good tire. looking for all weather (I live in New England)
 

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Hi,
I cannot answer for the limits of what will fit the rim OR what will still have clearance inside the frame and chain and so on.... But I can tell you how the tires are sized.

An example is easiest to explain this.
Example 130/80-17..

130 is the width of the tire at the widest point given in MM. (divide by 25.4 if you want inches)

80 is the ratio of height to width above the rim diameter. In other words, using the point where the tire meets the rim at the reference diameter (in this case 17 inches), multiply 130 by 80 percent. Thus the tire height is 104MM above the rim.

And of course 17 is the rim diameter given in inches.

On any given bike you should be able to vary the first two numbers to a certain degree before you start having trouble. You cannot of course vary the final number at all without having trouble. I am not sure how much you can vary the tire size before you have interference. I seem to recall threads talking about how on a Bonneville, if you go over 150 width you might start rubbing the chain. But I'm not certain if I remember that correctly.
Do a search in the forum and you should find some of that information. Other members have explored this quite a bit.

Good luck
 

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Why is it you want to go to the fattest size you can put on? Appearance, I expect?

The manufacturers specify the OEM size tires based on extensive testing, to provide optimum handling. It is possible to vary a bit from the stock size without upsetting things, but you'll find your plan will make for straight line comfort, while making cornering a chore.

If you're set on replacing the stock rubber you'd be better off to buy some premium tires in the stock size.
 

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avons

I went with the avon azzaros, sized 140 rear and 110 front. Had Metzlers and Bridgestones prior, wasn't happy with wear rate. Got nearly 5K on avons, wearing well and handle great. The bigger tires don't seem to effect handling any differently, at least the way I ride. The 130s on the rear seemed to wear down themiddle fast, the 140s with the wider contact patch seems to be holding up to wear much better. Just my observations..

Hoopla
 

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i stuck with the stock sizes and have Pirelli Sport Demons. No complaints at all except it seems like southern california highways like to wear out motorcycle tires very fast. these tires are great and super sticky. huge improvement over stock. consulted friends who eace thruxtons and they race with the stock sizes (non-thruxton cup), so if it's good enough for them it's good enough for me.
 
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