Sport 90 tires

[Hap]

I knew this day would eventually come and now my original back tire on my 1966 Sport 90 no longer holds air. Should I just place a tube in it or replace with new tires? The original front tire still holds air. The original tires look cool and really make the bike IMHO, but I guess a little safety may come into play here. I have no idea what people use for replacement tires on these? Size says 2.5-17 on original tires. Will just a tube placed inside be OK?

[dcr]

Hopefully someone has some good info Hap. My 100 sport needs new tires as the originals have a severe case of dry rot.

[OldSwartout]

Your tires already have tubes in them. The tube in the back one probably just got damaged or became too brittle.  However, original tires are probably not safe to ride on even with new tubes. They may be fine for a casual ride on smooth roads, but all you'd need to do is hit a chuckhole and the cords might not hold.  There are several threads on here about various suppliers for tires for 175s and 350s that look similar to original, but you won't find anything exactly like the originals.  You can go online and look for tires, with all the scooters and other small bike these days, there should be something available. However, the sizes will be listed as metric, so you'll need to look for something in a 65 or 70mm section.  Some 90/100 owners will surely chime in here.

[Dan44]

I just bought a pair for my bs 90 sport.  I called a local motorcycle shop, gave them the size and they had them the next day. I went cheaper since I don't ride it much so 2 tires and 2 tubes were $77.  I'll just have to mount the tires myself.