General Category => Wheels & Tires => Topic started by: Derek on February 12, 2017, 01:20:58 PM

Title: Inner tubes
Post by: Derek on February 12, 2017, 01:20:58 PM
hi - I just got some new Coker tires (26x2.50) and thought I'd put some new tubes in while I am at it. I bought a pair of 26x2.125-2.75 heavy duty tubes but they are way too big (diameter). What size should I be getting?
Title: Re: Inner tubes
Post by: Ricks on February 12, 2017, 01:45:11 PM
hi - I just got some new Coker tires (26x2.50) and thought I'd put some new tubes in while I am at it. I bought a pair of 26x2.125-2.75 heavy duty tubes but they are way too big (diameter). What size should I be getting?

Are they bicycle tubes? If so, they are not too big.  That is what 99% of the Simplex bikes out there run.

 I prefer the motorcycle tubes with the screw in valve stems.  I use the 21 x 2.50-2.75 size.  Check my thread on my 1955 restoration for a picture of the tubes that I use.
Title: Re: Inner tubes
Post by: Derek on February 12, 2017, 04:39:28 PM
I assumed they were bicycle tubes, bought off ebay, they look like they'd fit a 29" wheel.
Title: Re: Inner tubes
Post by: Ricks on February 12, 2017, 04:52:28 PM
I assumed they were bicycle tubes, bought off ebay, they look like they'd fit a 29" wheel.
Without a picture of the box to verify, I'd say you have he correct tubes.

I don't know if you are aware, but a Simplex rim is the same size as a 26" bike rim.  Bike rims are measured by the tire size, whereas a motorcycle rim is measured at the rim.
Title: Re: Inner tubes
Post by: Derek on February 13, 2017, 09:16:36 AM
They were supposedly bicycle tubes. Maybe I can return them.
Title: Re: Inner tubes
Post by: Ricks on February 13, 2017, 09:23:26 AM
They were supposedly bicycle tubes. Maybe I can return them.

26 x 2.125-2.75 bicycle tubes are correct.
Title: Re: Inner tubes
Post by: Derek on February 15, 2017, 08:05:03 AM
I am not sure what I am doing wrong, I ordered another pair of tubes 26x2.25-2.50 and they are way too big (diameter) for the rims too. I got them through Amazon, they were described as bicycle tubes as did the boxes. The tires are 26x2.50. What is going on?
Title: Re: Inner tubes
Post by: ndian22 on February 15, 2017, 12:04:37 PM
Derek are you just eyeballing tube to rim or are are you actually installing and airing up tube, tire, rim strip and wheel as a complete unit?
Title: Re: Inner tubes
Post by: Derek on February 15, 2017, 12:37:23 PM
I have installed it on the rim, with strip, aired it up. No tire. It looks like it would fit a rim 2 inches bigger. I can put my fist in the gap between the tube and the rim. I used enough air to bring it to shape, not overfilled.
Title: Re: Inner tubes
Post by: Ricks on February 15, 2017, 01:02:13 PM
I have installed it on the rim, with strip, aired it up. No tire. It looks like it would fit a rim 2 inches bigger. I can put my fist in the gap between the tube and the rim. I used enough air to bring it to shape, not overfilled.

1st Install rim strip
2nd Install one bead of tire
3rd Install Tube
4th Install second bead of tire
5th Air the tire to 35psi
Done!  You have the right tube.  The tire keeps the tube from expanding outward, but will expand inward until the rim stops it. Don't overthink it.

If you think those bicycle tubes look big, try the motorcycle ones I use.
Title: Re: Inner tubes
Post by: Derek on February 15, 2017, 02:43:42 PM
I have installed bicycle and motorcycle tires but have never seen this big of gap between the tube and rim, but I will say that I never looked at a tube on a rim. I would usually stuff them in the tire and go with it.
Title: Re: Inner tubes
Post by: kartjockey on April 16, 2017, 09:51:02 AM
Just re-reading these posts.  Just a thought to add to the mounting process. I like to sprinkle talcum powder in side the tire and around the tube.  This will help it to slide as needed as the tube inflates and prevent it from maybe doubling itself over.
Title: Re: Inner tubes
Post by: carryall on April 16, 2017, 09:57:18 AM
Never thought of doing that.  I've wet the tube before with water.
Title: Re: Inner tubes
Post by: Ricks on April 16, 2017, 10:00:37 AM
I like that idea!  I use the motorcycle tubes, and they can bunch up a little, as they are much heavier than the bicycle tubes.  I also like to leave the schrader valve out, and air them up and down a couple of cycles before reinstalling the schrader valve.  This seems to help them unwrinkled themselves.
Title: Re: Inner tubes
Post by: pd on April 16, 2017, 12:24:23 PM
Along the same lines : dish soapy water seems to do much the same . I put it in a spray bottle , which makes application very easy . ;)

Pete . :)
Title: Re: Inner tubes
Post by: OnaWingandaPrayer on April 16, 2017, 05:12:17 PM
I used to use soapy substance to install tires .  I now use armorall. It has less chance of causing rust to begin or corrosion on aluminum wheels.
Title: Re: Inner tubes
Post by: pd on April 16, 2017, 05:40:12 PM
I hope you know that there is much discussion that Armorall actually breaks down rubber and vinyl in the long term .
Here's a thread that seems to be on point : https://www.tamiyaclub.com/forum/index.php?/topic/27045-why-silicone-oil-is-great-for-rubber-and-armor-all-isnt/

We use soapy water to install carb tubes on aluminum and have for many years . Not a single sign of any type of corrosion . It's not like anything gets totally soaked . ;)

Pete . :)
Title: Re: Inner tubes
Post by: OnaWingandaPrayer on April 17, 2017, 05:21:26 PM
Thanks for the link . I will be doing more reading on the armoral subject .  It was one of my motorcycle forums where the recommendation was to use armoral on our aluminum wheels. Again thanks for stirring my thoughts on the subject.
Title: Re: Inner tubes
Post by: pd on April 17, 2017, 06:44:51 PM
(http://www.cb750c.com/modules/Forums/images/smiles/stir.gif)  LOL

My pleasure .

Pete . :)