Bias ply rear tire

[Gsxxx600]

Ive seen some kat's with a bias ply tire on the back...I believe the pre98's were equipped with bias plys too.

Anycase,
I understand what a bias ply is, but is there a certain way to read them?
In other words...a radial is 140/80/17...is a bias ply the same?

Thanks...hope that makes sense^^^

[md86]

Yup . My Sport Demons are bias ply (which I didn't know when I bought them ) , and are sized like that . I believe that's the "metric" way of sizing tires , bias-ply OR radial . Then there's the SAE way (I guess that's what it'd be) with the whole inches thing . I've seen radials use THAT sizing method as well .

[Gsxxx600]

so basically,

if the measurements are the same, a bias ply tire depends on who manufactures it.

got it!

[md86]

Manufacturers make both radial and bias . The size thing is kinda like this...we Americans still use SAE measurements most of the time (inches vs. cm's , foot vs. meter) , while everyone else uses metric . Here's an example...100/80/16 = 3.25/3.50x16" . See ? Same size , different units of measure .

[The CyberPoet]

To read tires, it goes like this:

150/70ZR17 (62W)

Where:
150 is the tire's width left to right across the tread area in millimeters;
70 is the sidewall height as a percentage of the first number (i.e. - in this example 70% of 150mm = 105mm);
ZR is the speed rating (Z) and if required the radial (R) or Bias (B) requirement;
17 is the wheel diameter in inches;
(62W) is the weight rating (62) and any special manufacturer codes (W is often "weight", but they could also have "RR" for road racing only, etc).

THINGS TO KNOW:
1. Bias (non-radial) tires generally are 1/4 wider at each lip than comparable-sized radials because of how the lip is formed;
2. Front and rear tire treads and crowns are designed to work together to sweep water or loose debris out of the way; the front tire clears for the rear tire's tread pattern, and is the reason manufacturers all recommend using the same brand & model tires front and rear together as a pair.
3. Front and rear crown apex designs are designed to work together to provide a consistant lean angle for the bike, to reduce unnessary flexing from mis-matched lean angles; this is the other primary reason that all tire manufacturers recommend matching brand & model front & rear tires.
4. Of all the manufacturers, only Dunlop permits patch of punctured tires, and then only certain models of rear tires, single patch, and when patched, the speed rating drops to 70 mph.
5. All tires "grow". Typical street tires grow in size about 5% - 8% during the first 10 days of ownership from being under pressure and heating cycles; race tires grow even further (as much as 22%).

I'll post a link sooner or later with all the tire info I have...

Cheers
=-= The CyberPoet

[WildKat]

Yup!! what he said...

[Gsxxx600]

ahh i can see clearly now
thanks all