tire/tube question

[Anonymous]

Ok, got the 76' spokes for the 82' GS550, everything will matchup but I have to get a new rear tire. I'm running Dunlop GT501 on the front and going with that for the rear. The new rear spoke rim is a "215x18", 3" width, 18" diameter. Therefore, I'm thinking about a 130/80-18. Is this an appropriate size? Also, with spokes I'll need to go with tubes. First time with spokes and tubes, any problems running a tube with this tire, and if not what size should I use?


Thanks
curt

[Anonymous]

tire

if the tire isn't a radial and not meant for tube less application, (there is pros and cons on this) you should be ok, but you might want to check to make sure that it will clear every thing first, i.e. chain and guard, with the tire pushed forward into the swing arm, dont forget about using a new rim liner, and properly secure the valve stem

[jimcor]

First off your rim width is not 3 inches it's 2.15. So that means it's for a 110 series tire or 120 maximum. 2.50 is the minimum rim width for a 130 series tire. Spooning a 130 on that narrow rim distorts the tread pattern. You've got to remember there was not a big 'wider is better' craze going on in 1976 and that 550 rim probably came with a 3.50X18 inch tire.

You will have no problem running a tube in a tire that is stamped tubeless.

If you decide to still use a 130 tire check your clearances at the brake rod, rear of swingarm, chain and top of fender.

[Anonymous]

Jim,

Thanks for catching that for me! I was measuring across the lip of the rim to get 3". The 215x18 is definately on the rim but for future reference where should I be measuring to get an accurate rim width?

I don't have any interest in putting too much tire on the rim (not trying for a wide look). Looking at Dunlop's site they don't offer a 110 in that diameter and the only one left would be a 120/90-18. In your opinion would this work?

Thanks.

[jimcor]

Jim,

Thanks for catching that for me! I was measuring across the lip of the rim to get 3". The 215x18 is definately on the rim but for future reference where should I be measuring to get an accurate rim width?

I don't have any interest in putting too much tire on the rim (not trying for a wide look). Looking at Dunlop's site they don't offer a 110 in that diameter and the only one left would be a 120/90-18. In your opinion would this work?

Thanks.

Yes, the 120/90X18 will work according to the chart I have. As far as where to measure for rim width...I dunno . You'll find the size stamped/embossed on most rims. You might play around with a straight edge and a caliper, if you have one and let me know!

[Anonymous]

Ok, that's what i'm going with! The new wheel and tire will be 1.5" larger in diameter and .5" narrower and I checked the clearances on the bike and everything looks good.

The earlier poster said to "properly secure the valve stem" -- does that mean just make sure the valve stem is properly seated in the hole in the rim?

Thanks

[jimcor]

Let's start at the the beginning, good place, eh. Mount one side of the tire to the rim. Add just enough air to the tube to give it shape. Cover the tube with a bit of talcum/baby powder. Don't skip that step, the powder helps the tube to seat and helps prevent pinching and/or holing the tube. Don't have any? Get it at the dollar store, you can always use it in your boots, makes 'em slip on easier and smell better! Insert valve stem in hole. Use jam nuts finger tight to hold it in place. Install tube in tire. Be careful, spoon the other side of the tire on the rim. Remove valve core, inflate tire. Is valve stem straight? Yes? Good! Again tighten jam nuts finger tight, let tire deflate, repeat inflation-deflation a couple, 3 times. This lets the tube get situated in the rim/tire. Install valve core, inflate to spec. Retighten first jam nut just a little more than finger tight, lock with second nut, use 2 wrenches or pliers-wrench combo.

Because the tire changing gods were smiling and you used talcum powder, and real tire spoons or irons and not screwdrivers the job was a complete success and you're ready to ride after installing the wheel!

[Anonymous]

thanks for the help Jim!!

[jimcor]

Your welcome. Oh I did screw up I used the word stem in a couple of places where I should have typed core...went back and edited it.

[Sandy]

Jim's recommendations for tire changing is right on. One other tool I find valuable for tire changing is a good old garbage can without the lid. Perfect working height and the tire/rim assembly stays nice and flat (OOPS! I meant level) and doesn't wobble all over the place while you're working on it. If it's a metal can just make sure you cover the edge with rags to avoid scratching the spokes.

[earlfor]

The measurement is inside to inside at the rim lip.

Earl

[quote="curt2005"]
The 215x18 is definately on the rim but for future reference where should I be measuring to get an accurate rim width?