Official YARIS Wheel & Tire Guide

[Doc Zaius]

Here's a cut & paste from an Excel spreadsheet I made up a while ago to help determine various tire sizes. Both models' sizes are included (as there is a 3.41% difference in diameter from the base to the RS model!). This doesn't take into account the ratio between wheel widths and tire widths.

Base Model with 175/65/14:

	Width	Aspect	Wheel	Diameter	Circumference	Difference
	(mm)	(%)	(in)	(mm)	(in)	(mm)	(in)	(mm)	(in)	(%)
							
Orig.	175	65	14	583.10	22.957	1831.86	72.121	--	--	--
										
+1	185	55	15	584.50	23.012	1836.26	72.294	4.4	0.17	0.24%
	185	60	15	603.00	23.740	1894.38	74.582	62.5	2.46	3.41%
	195	55	15	595.50	23.445	1870.82	73.654	39.0	1.53	2.13%
	195	50	15	576.00	22.677	1809.56	71.242	-22.3	-0.88	-1.22%
	205	50	15	586.00	23.071	1840.97	72.479	9.1	0.36	0.50%
										
+2	195	45	16	581.90	22.909	1828.09	71.972	-3.8	-0.15	-0.21%
	195	50	16	601.40	23.677	1889.35	74.384	57.5	2.26	3.14%
	205	45	16	590.90	23.264	1856.37	73.085	24.5	0.96	1.34%
	205	40	16	570.40	22.457	1791.96	70.550	-39.9	-1.57	-2.18%
										
+3	205	35	17	575.30	22.650	1807.36	71.156	-24.5	-0.96	-1.34%
	215	30	17	560.80	22.079	1761.81	69.362	-70.1	-2.76	-3.82%
	215	35	17	582.30	22.925	1829.35	72.022	-2.5	-0.10	-0.14%
	225	35	18	614.70	24.201	1931.14	76.029	99.3	3.91	5.42%
	225	30	17	566.80	22.315	1780.65	70.105	-51.2	-2.02	-2.80%

RS Model with 185/60/15:

	Width	Aspect	Wheel	Diameter	Circumference	Difference
	(mm)	(%)	(in)	(mm)	(in)	(mm)	(in)	(mm)	(in)	(%)
						
Orig.	185	60	15	603.00	23.740	1894.38	74.582	--	--	--
										
+1	195	50	16	601.40	23.677	1889.35	74.384	-5.0	-0.20	-0.27%
	195	55	16	620.90	24.445	1950.61	76.796	56.2	2.21	2.97%
	205	50	16	611.40	24.071	1920.77	75.621	26.4	1.04	1.39%
	205	45	16	590.90	23.264	1856.37	73.085	-38.0	-1.50	-2.01%
	215	45	16	599.90	23.618	1884.64	74.198	-9.7	-0.38	-0.51%
										
+2	205	40	17	595.80	23.457	1871.76	73.691	-22.6	-0.89	-1.19%
	205	45	17	616.30	24.264	1936.16	76.227	41.8	1.65	2.21%
	215	40	17	603.80	23.772	1896.89	74.681	2.5	0.10	0.13%
	215	35	17	582.30	22.925	1829.35	72.022	-65.0	-2.56	-3.43%
										
+3	205	35	18	600.70	23.650	1887.15	74.297	-7.2	-0.28	-0.38%
	215	30	18	586.20	23.079	1841.60	72.504	-52.8	-2.08	-2.79%
	215	35	18	607.70	23.925	1909.15	75.163	14.8	0.58	0.78%
	225	35	18	614.70	24.201	1931.14	76.029	36.8	1.45	1.94%
	225	30	18	592.20	23.315	1860.45	73.246	-33.9	-1.34	-1.79%

Wheel width to Tire width Ratios:

Tire Width	Wheel Width in inches, and the wheel/tire ratio
mm	inches	5	5.5	6	6.5	7	7.5	8
175	6.890	72.57%	79.83%	87.09%	94.34%	--	--	--
185	7.283	68.65%	75.51%	82.38%	89.24%	96.11%	--	--
195	7.677	65.13%	71.64%	78.15%	84.67%	91.18%	97.69%	--
205	8.071	61.95%	68.15%	74.34%	80.54%	86.73%	92.93%	99.12%
215	8.465	59.07%	64.98%	70.88%	76.79%	82.70%	88.60%	94.51%
225	8.858	56.44%	62.09%	67.73%	73.38%	79.02%	84.67%	90.31%
235	9.252	54.04%	59.45%	64.85%	70.26%	75.66%	81.06%	86.47%

Hope this helps, and adds to the information already provided!

Z