Rear tire

[Zihuamark]

Has anyone tried running a 140/70-18 on the rear?

[Strokeofgenius]

I have only ever had a 14070/18 on my rd.What should it be,I've had no problems anyway.

[RZ 500 N]

I have only ever had a 14070/18 on my rd.What should it be,I've had no problems anyway.

Originally, it was the 130/80-18. And the rims I believe are 2.5", and according to the https://s3.amazonaws.com/helpscout.net/ ... -Chart.pdf the 130/80 is the biggest tire for a 2.5" rim. Tires are designed for a certain rim width, you exceed that recommendation, you could very well have issues. Page 3 of the chart, some specifics are explained, like what happens when you use a tire to big for a rim and when you use a rim to big for a tire. Me, @ 70 - 80 mph in a turn, I prefer a tire working as its designed. Hope this helps.

[Bengt Weil]

Original rear rim is 3.00 x 18 while the front is 2.75 x 16.

[RZ 500 N]

I stand corrected. That s funny though, the one wheel I looked at for reference shows it's 2.5" https://www.ebay.com/itm/275287930747, but it turns out it's from an RZ350, it was just posted incorrectly. I kind of thought it didn't seem right, but didn't dbl check it.

So, that would make a 140/70 as big as you could go. But actually I would stay with the 130/80 with 3.0" rim.

[Strokeofgenius]

Many thanks for the update and excuse the late response.The next time my bike needs a back tyre I will put on the proper130/80.These old girls need all the help they can get.