tires or tubes ?
- Thread starter jpdidit91
- Start date
The tube is what holds the air, so if you have flat...you have a bad tube. If your tire has a cut or hole you need a new tire as well. If you just pinched it on a rock and didn't cut the tire and the tire is still in good shape just change the tube. Pics of the tire will help us decide for you. 
Only if a tire is worn out, it's replaced. If the leak is say a cacti needle and you can't find it after looking, and you keep getting a pin hole leak, then replace it no matter how good it is.
Does anyone happen to know the correct rear tube size for a 03 crf 450r . My tire says . 100/90/19 and I orderd a heavy duty tube that size and they sent me a tube 110/90/19 and a note saying the 100 wouldn't fit . But the one they sent looks huge ... bigger then my rear tire wen held up .
Typically you find the 100 on the 125 two strokes and 250f's. 110's are my favorite on what you have and 250 two strokes. Some even like 120's. Check and see if your rim has 2.15 on it. If it does you are set for a bigger tire. If it says 1.85, someone has slipped a smaller rim or complete wheel on that somewhere in the past. In that case you may want to stick with the 100. The narrow rim and narrow tire is used by some people on tracks or trails that have really deep ruts in them. Those riders prefer to be able to stay down in the rut rather than have the tire trying to climb the sides etc. So go check your rim and decide what to do about rubber. FYI I have certainly stuffed a tube that was too big into a smaller tire. It is easier to pinch it and make it leak for some people.
According to my handy dandy notebook, The stock tire size for front is 80/100x21 (2.50x18) and rear is 110/90x19 (3.75x19) for the 2003 CRF450. 110/90x19 tube can fit in a 100/90x19 and vice versa, but I recommend the right size tube for a variety of reasons. The 19x2.15 is the average size for MX bikes, and the front is typically 21x1.60.
2.5 x 18 ??? When they came with the old dims the more common was 3.00 x21. Cz's came with 2.75 Barum fronts, suposedly better for mud. You can get it in, i use the dry method for an oversized tube, lots of talcum powder or similar for getting it in, just a little bit of air will make it slip in a little bit better. Again though, that tire was intended for the 125/250 f's. like my crf 250 those come with a 1.85x19 rim. So when you wear that one out you have an idea what to shop for.
Got to love it when they "edit" your requests. The strangest one I had was from a dealer called Midwest Action Cycle. I ordered a smaller rear sprocket than stock. They sent me a stock one and when I called them, this very girlie sounding guy said "we shipped you the "right size", you had ordered the "wrong size". LOL thanks for straigtening me out here, old "anything but straight".
Got to love it when they "edit" your requests. The strangest one I had was from a dealer called Midwest Action Cycle. I ordered a smaller rear sprocket than stock. They sent me a stock one and when I called them, this very girlie sounding guy said "we shipped you the "right size", you had ordered the "wrong size". LOL thanks for straigtening me out here, old "anything but straight".
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