tire tube fitment on my XR600r ...

im pretty sure i know the answer , but wanted to make sure .

im turning my 93 xr600r into a dual sport . i plan on ordering bridgestone bt45s for the front and rear .


90 90h 21


130 80v 18

these are going on a totally separate set of rims so i can swap rim/tire combos from street to dirt easier .

i need to buy tubes for the tubeless street tires . will any 21" and 18" tubes work?

i found a 130/80x18 tube on ebay as well as a 90/90x21 ... these will fit ok right?

i just was worried about having the tube match the rim width rather than the tire. thanks !

someone told me just to get stock tube size , so 90/21" and 110/18" tubes , and those should work for the front 90 and rear 130 . just would like to verify

someone told me just to get stock tube size , so 90/21" and 110/18" tubes , and those should work for the front 90 and rear 130 . just would like to verify

Personally i would get the matching size.the 110 will fit the 130.....put as you go bigger on the tire the tube has to stretch to match,getting thinner........in practice it prob makes no diff.........

I also firmly berlieve the only reason i have never had a flat in 10,000 is that i buy decent tires AND bought the proper sized tubes that are 4mm thick.....

Money well spent on 4mm tubes..they survive pinch flats where others can leave you freekin stranded ..........

Of course nver having a flat involves some luck too.......a nail or sharp object is going to pop through any tire......


According to the manufacturers site the rear tire you selected is too large for the rim. Your bike has a 2.15 inch rim and the 130 is for a 2.5 rim. The 120 width is recommended for a 2.15 inch rim. Now the 130 will work, it's just not optimum. As strange as it seems the 120 may actually have a larger contact patch and it will almost for sure get more miles than the 130. The 4.00 and 110 widths might even be better. The downside? They look so skinny.

As far as tubes go it really doesn't really matter the exact size. Anything mentioned will work. There is an issue with using tubes in tubeless tires. The tubes wear against the inside of the tire and there is extra heat generated. Be sure to replace the tubes EVERY time you change the tire.

Just so you know the BT45 is available in a tube type tire in 90/90-21 and 4.00-18 which will fit your rims. The tube type designation means that the inside surface if the tire is smooth and your insurance will not deny coverage in a tire failure situation.

Pinch flats on a street tire? How does that happen?


good info ... thanks ! luckily we were thinking along the same path . before you posted, i bought my tires last night .... though i didnt see bt45s in tubed ... anyways , i bought them on amazon and went with a 90/90 front and a 120 80 rear . seemed more practical . hey , its not a crotch rocket , so i dont need big tires . i just got standard tubes off the BaY but they are the exact size of the tires (90/90 and 120/80) . wish i woulda known any tube mentioned above would have worked cus i would have gotten the msr heavy duty ones. i should be fine though , seeing how they will be an exact fit to the tires and they will be on the set of rims permanently until i replace the tires.

i hope i dont get into an accident from a flat... thankfully i wont be riding this thing all the time .

heres the tires i picked . i just got plain old tubes . .. nothing fancy .





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