sulavaca wrote:I have information which states that for European metric tyres, the aspect ration for that 155SR13 tyre is 82, which in this case, would put its height at 131.75mm and quite a way off from your other tyre which is 122.5mm.
Also the width is quite a long way off too. You are no doubt going to have some steering and/or other performance issues if running these tyres at the same end.
This will most likely only do as a spare and used for only a short distance.
shawn_c wrote:I've run wider and/or taller tires on cars before and they don't present a safety issue. They may make your speedo off by a little, but hey, is that such a big deal?
Even if the Chengshin 155 R13 are 82 aspect ratio (instead of the 80 as per your screenshot there), a 10 mm difference isn't going to cause rubbing issues - and that's the issue you need to be worried about here. The Chengshin is also skinnier than your current tire, which means there certainly won't be any fitment issues (horizontal fitment, rubbing up on shock, etc.).
All that said, it's possible to fit a wider variety of tire on your scooter or car than you think; you just have to watch out for rubbing issues AND rim fitment issues.
I wouldn't use your Chengshin anyway... a five-year old tire is not going to be as good as a new tire (even if it was never used). Why risk the most important safety aspect of a two-wheeler for $1,500?!?!
thirdstring wrote:Mixing tire sizes on an axle is absolutely a safety issue! .
As for deflating the spare, you would need to seal the spare externally in a bag or something as well if you're concerned about deterioration. .
However, If you just use your spare as a spare (I know, it's a waste!), you only need it to last for a relatively short distance. I had a spare on my truck that had probably been there for 15 years without being touched, and it was still good to go when I got a flat. Sitting under the truck, exposed to exposed to moisture, snow, salt, sand, etc..
thirdstring wrote:Here's some good info from Goodyear. It's about RV tires, but I think it probably still applies in general. 10 psi for storage.
Also, sounds like oiling them is not a good idea. The bag would be the best way to go.