CMP tyre installation
 

CMP tyre installation by Jim Ritchie

The author is in favour of machining the rims by 1/8”

Attachment 127021

This is a topic that comes up from time to time.

The need to remove material from a 16" rim is only necessary (or useful, at least, if not necessary) for 8 stud CMP wheels fitted to 15cwt and 30cwt trucks (and similar such as on Lynx II or 25Pdr, etc).

It is NOT required on 16" 6 stud CMP wheels as fitted to 8cwt (HUP, C8AX, etc) or Lynx I, as these wheels are already to the US 16" dimensions.

That is a very good addition Tony, thanks!

When I put my new tires on the rims they went on without issue and didn’t need any machining or removal of the bead.

I recently bought Michelin XY 9.00-16 tyres and they fit the 15-cwt CMP rims without modification: http://www.mapleleafup.net/forums/sh...931#post283931
There are variations between manufacturers, so I would say it is best to buy tyres, then see if they fit. If they don't, apply one of the options mentioned above.

The main reason I posted Jim Ritchie’s experience is that I asked a friend who had his rims turned down / machined, how it was done and how much was taken off. They man that did the machining for him no longer does this work but he followed the guideline above.

What comes around goes around........
 

Wen faced the same thing years ago....in fact over a decade ago and the solution was easy enough........ we built our own tire installer machine from stock steel. I even installed new tires on clean rims with my wife helping me it was that easy.

I have seen MLU guys trim their tires down to the steel cable of the new tire bead and heard of grinding the rims....... to me both are flirthing with danger and absolutely unnecessary.

First of all our rims were used and rusted. They were all cleaned with a needle gun then sand blasted than washed with Phosphoric acid and painted with POR 15 to a gloss finish. Tires were still tight and we did install tires on relatively new rims taken form trailers.....they had no rust and still had some original OD paint inside...some had the run flat rubber spacer.

Part of the trick is the glossy paint on the inside of the rim...... then use some professional tire lubricant or known as tire "snot" ....... we get our from the truck tire shop ... it is a gel like lub best applied wearing rubber gloves and it is claimed to be non water based and will not rust steel rims. The lub also works great on the tube and the rubber flap.

Then you need a tool like what we made which gives you easy mechanical advantage to press the rim onto the rim. I HAVE A SET OF PICTURES THAT WERE PREVIOUSLY POSTED ON mlu........ I just need to find them in my thousands of other pictures. Believe me it works, is safe and will not damage the new tires............. I will follow up. and Hanno can make a STICKY FOR TIRE INSTALLATION.

For removal we did purchase a manual tire bead breaker and managed to abuse it with a CMP tire that had frozen water/ice on the inside .....so we modified it with a hand made part from a thciker cross section.... it is slow but does work with no damage to the tire bead....will also include photos.

You will need one inch by 2 inch square tubing....... grade 8 threaded rod 3/4 inch and grade eight nuts....... a welder and some axle grease lubricant for the threaded rods to prevent galling of the thread. Solid bar stock in approx. same size can be used but more $$ and heavier.

Check tomorrow for pictures and Imperial dimensions....... as far as I know it is my original invention and never copied commercially.....and patent free.
I just got tires of driving to the truck shop and paying $15 per wheel for them to use a $500 hydraulic device in less than 5 minutes of work.

Hang on...........

Bob C.

PS.....NOW REALIZE THAT ALL THE INFO IS POSTED IN THE HOW 2 SECTION......