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Home Repair And Restoration

Abject Failure

Failure Date 20 September 2023

By Ren Withnell

In one of the chats or comments recently I mentioned I had a new technique for fitting tyres to a motorcycle.

Hmmmmm.

A while back Sharon required a new front on her Z250SL. Using this new technique fitting a Michelin Pilot Street was an doddle, I barely even raised my heartbeat. I was going to do a piece on this fabulous new technique but before I did I thought it prudent to see how well it works on a meatier tyre, say one on my CB500X.

A cross section diagram of a tyre, bead, rim and well on a motorcycle
Take NOTE! I'll be asking question later.

At 15,000 miles the Pirelli Diablo Strada on the front is down to 2mm. Normally I'd squeeeeeeeze a little more out of it but with another not-too-big a trip coming soon I think it wise to fit the Pirelli Angle ST I have in the loft rather than get caught out for being bald. You may also recall my trauma of a front puncture and why I presently have a Pirelli fitted and not a Conti-Motion. I've always used Continental Conti-Motions, but their prices have gone silly, hence the Pirelli. I've fitted several Conti-Motions with much fighting and cursing but with my new technique this will be a doddle. 

Hmmmmmm.

Breaking the bead on the worn out Pirelli is hard, much harder than I remember on the Conti-Motions. Getting this old tyre off the rim is a battle royale. My new special technique helps with getting the first side of the tyre off... a bit. However getting the second bead off, usually the easier part, sees me heaving and straining and levering and tugging and yanking. I wonder, I wonder... This Pirelli carcass is stiff?

A long metal bar, slotted angle bolted to the wall and a wooden block make the home made bead breaker
Even with the home made bead breaker I'm still heaving hard.

Shaking and sweating from getting the old tyre off I grab the new tyre from the loft. As soon as my hand touches the carcass I feel a shiver down my spine. This doesn't feel like a soft, pliable, squidgy 125 or 250 tyre, this feels like the kind of tyre you'd fit to a Gold-Wing or Harley. It's "well 'ard". Poop. Pirelli makes stiff tyres.

So, what is my new and wonderful technique? We all know the key to changing a tyre is to ensure the bead is right there in the well, fully off the shoulders. The whole purpose of the well is to facilitate tyre changes. Normally when changing a tyre we ensure the bead we are working on is in the well and don't concern ourselves about the other bead. 

Well (sic) get both beads in the well!! This allows the whole tyre to move so rather than fighting the bead AND the carcass you're just fighting the bead. As such I've been using straps to hold both beads deep into the well at the opposite end to where I'm pulling off (or levering on) the bead. This is what (is supposed to) make the "zip tie" trick work.

3 ratchet strap around the trye and rim to push the tyre into the well
The straps aim to force BOTH beads down into the well,
the old tyre is scrunched up as both beads have dropped into the centre of the rim
See the rim clearly on both sides? Both beads are in the well and the tyre is squeezed in there.

This of course is only necessary at the start of the tyre removal, with both beads on the rim still. Now - the old Pirelli was hard to remove when just one bead was in place. Getting a new tyre's first bead on is usually a doddle - bit of lube and a few firm pushes just from your hands. Nope. The Pirelli is TIGHT and requires levering on. This means Pirellis are very tight on the diameter of their beads. This does not bode well at all.

The carcass is so stiff I simply cannot squeeze it such that both beads are in the well. I squeeze with my big butch manly hands, I can get one bead in the well in but not the other. I squeeze with a g-clamp and get both beads into the well but I can't get the strap tight enough to keep both beads in the well. I squeeze and fight, fight and squeeze, trap fingers, pull muscles, chip paint off the rim and all to no avail. 

Suffice to say I try everything. When I give up there's clamps and straps and soapy water and and levers and gaffer tape  all across the floor, as well as some dried blood that will be part a of the front wheel for the next 15,000 miles (hopefully). I end up heaving and pulling and yanking the tyre on in the usual manner. There is nothing slick, easy, quick and painless about this tyre fitting experience.

Tyre spoons, a rim guard and frustration
Damn, blast, poop, grrrr...

My new and special technique is valid, but it is not a panacea. It still remains a fact that the more of the bead(s) you can get into the well, the better. Always ALWAYS focus on getting the bead, ideally both beads, into the well as much as possible. Do anything and everything you can to get the bead(s) into the well. It is also worth noting some tyres are a LOT stiffer than others. The stiffer the tyre, the more circles of hell you will need to pass through to fit the tyre. 

Stiffer tyres also make an enormous BANG when they finally rescind and pop onto the rim when inflating. For a brief moment I thought I was dead. 


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Reader's Comments

Upt'North ¹ said :-
I was going to ask you why you subject yourself to this torturous life, but that'd be stoopid, right?
I'm guessing you saved a tenner?
My last tyre fitting experience by way of comparison went like this.

Little Richie, two A41's on the shelf for me please.
If you pay now I'll let you off for the fitting.
OK see you when I'm ready.

LR, can I pop down and get em on.
No probs what about tomorrow.
Spot on see you then.

LR, slow down I haven't finished my tea yet.

That's all I've got.
Upt.




13/10/2023 09:10:23 UTC
Ian Soady¹ said :-
You know Ren: he only does it to annoy, because he knows it teases.......

What I didn't know till I looked it up is that Lewis Carroll's verse from which the above is stolen is in fact a parody of a Victorian homily - see link below. Perhaps something we could all take on board.


https://www.carleton.edu/departments/ENGL/Alice/Footspeakroughly.html...
13/10/2023 10:08:20 UTC
nab301 said :-
Ren , I was looking forward to this thread for ages ! While waiting I looked at many cable/ Zip tie methods of removal / fitting , however most of these videos show and state that the beads should be clamped together before removal or fitting independent of the wheel. That is for removal , break the beads and insert the ties under the bead inside the rim and progressively tighten them until the beads are clamped together . However your straps are around the wheel which pulls the beads into the well of the rim but doesn't pull the beads together .
I guess I'll go my own way shortly and post up a reply....
Nigel

13/10/2023 13:19:11 UTC
Ren - The Ed¹ said :-
A friend and I have tried the zip tie method in the past - and reached the same conclusion. It's great and dandy if the tyre is pliable, it allows, as I have stated, to get both the beads into the rim. I see these YouTube videos where the YouTuber fits the zip ties so the beads are mashed together and slides the tyre on like fitting a slipper. Yeah, fab.

Now see how you go with a tight fitting stiff carcass. What tyre are you fitting nab301, onto which bike?
17/10/2023 07:57:51 UTC
nab301 said :-
Ren , I purchased Metzeler tyres earlier in the year for both DL250 and CBR500 but
a combination of less mileage travelled and very low wear rates means a change isn't required yet ... but I have a slow puncture in the rear of the Honda which I can't locate externally so I'll probably (attempt to) remove what I think will be a stiff walled OE Dunlop to investigate ! Cable ties purchased , just working up the enthusiasm , if that doesn't work I'll have to find my own Little Richie.
Nigel
18/10/2023 10:24:16 UTC
Paul said :-
I have only changed tyres on small bikes but found it much easier when the old and new tyres were nice and warm. Leaving in hot greenhouse, car or airing cupboard to get the temperature up.
18/10/2023 13:42:40 UTC
Ren - The Ed¹ said :-
You're absolutely right Paul, while heat is not the absolute solution (save for setting fire to the bike and buying a new one with new tyres) it sure makes a difference. Of course you're going to need a greenhouse on a warm day, a car after a long warm drive or an airing cupboard. I have no greenhouse, I have no airing cupboard and I'm far too miserly to put the heating on anyhow, which leaves me with the car.

nab301 - I don't know what Dunlop is fitted to your bike, but the Dunlops on my CB500X are quite soft - relatively speaking. They are (were) also blummin awful and the bike's ride and handling vastly improve once I replaced them. What on earth Honda are thinking fitting these as OEM is beyond me.
18/10/2023 16:45:44 UTC
nab301 said :-
@ Paul, yes I'm aware of the warm tyre easier fit.
@ Ren , Dunlop Sportmax D222, they seem fine to me in terms of handling , if a little lacking in grip on cold wet winter days.
The new Metzelers seem to succumb to cable ties ( see photo) , I'll report back on the Dunlops

Nigel
Posted Image
18/10/2023 18:25:46 UTC
Ren - The Ed¹ said :-
I can't help but feel sorry for a tyre when it's squished up like that.

My fear is what about the metal strands within the tyre? The wires in the beads are not being "overbent" so they'll be fine but I wonder if the fine wire strands in the tyre can be damaged with this much deformation? I think I'm paranoid, I know they're out to get me.
19/10/2023 07:50:12 UTC
nab301 said :-
Ren , I'm sure the tyres on your 500X are subjected to lots of stress and carcass deformation and are constantly flexing when you load up camping gear and travel down the road at 70mph hence why they get warm.
Nigel
20/10/2023 14:04:37 UTC
ROD¹ said :-
Nigel, Maybe there is a difference between design stress and carcass deformation when supported by air pressure, and the stress and deformation with zip ties when not supported by air pressure?
20/10/2023 14:48:12 UTC
nab301 said :-
@ ROD, That is quite possible, the photo ( a macro image) makes it look much worse and there was very little effort involved. I guess I/ we will never know unless there's a failure and luckily I haven't suffered any failures yet over the decades apart from routine punctures .


Joking aside I wonder is there some sort of diagnostic imagery that can be used on tyres.
Nigel
20/10/2023 19:19:55 UTC
nab301 said :-
So , the Saturday just gone I pulled out my paddock stands ( no centre stand on the CBR500) and removed the rear wheel while noting that all the components appeared to be of much better quality than those of my CB125F. Even the aluminium chain adjuster plate is a work of art...
I let the air out of the tyre, broke the beads easily ( more easily than the last time I removed the rear tyre from my 125...) with my home made screw type bead breaker , made a few attempts to insert cable ties , lost interest , and removed the Dunlop with no problems in the normal manner. I have to agree Ren , the Dunlops D222 are quite " Soft". The last time I fitted Dunlops was to my Bimmer years ago ( D208) and from memory were stiff.)

The rear Metzeler didn't seem too bad , so I lubed it (didn't bother with cable ties) and popped on the first bead by hand / size 12 boot pressure , no problem.
Because there were no issues , I carried on and the tyre was on with help from tyre levers, however the sliced up garden hose I was using as a rim protector somehow disappeared into the rim so I had to remove the bead to get at it , again no real problems refitting and inflated the tyre and popped the bead .
The front tyre was removed as above with no problems , The Metzeler replacement did prove to be stiffer but all in all presented no problems .
The following day I couldn't raise my arms above my head , I wonder was that related to my exertions the previous day or just advancing years!
Anyone looking for a cheap bag of cable ties?
Nigel


23/10/2023 14:19:48 UTC
Ren - The Ed¹ said :-
Yes I know exactly what you mean about the arms. There's some heaving and pulling when fitting a tyre that uses muscles seldom used in other circumstances. Maybe daily tyre fitting should be prescribed as part of a full body workout?

Glad you've been successful. I have reached the conclusion that if you were not at all fussed about your rim's paintwork the whole job would be, actually, quite do-able. Most of my struggles come from trying not to scratch, ding and otherwise ruin the paintwork. Steel rims anyone? I'd have no concerns at all about changing a car tyre on "steelies". However I would struggle to balance said wheel.
23/10/2023 21:10:06 UTC
nab301 said :-
Ren I think a lot of the reason for the successful job was due to the discussion in this thread, it got me in the right frame of mind ! I have no visible damage on the rims . You can search for plastic coated tyre levers but they never appear to be the correct shape.
The shape of the ones I recently acquired when helping a friend recently with an extremely difficult tyre fitting episode seems to help too. They have an extra lip which helps prevent them slipping and in conjunction with the obligatory rim protectors I also cover the business ends of the tyre lever with (large diameter ) heat shrink tubing . It's not very tough but is easily replaced after each use.
Nigel
Posted Image
24/10/2023 12:09:32 UTC
Ian Soady¹ said :-
They're very exotic levers Nigel - mine are old Dunlop large flat type (with a slight lip at one end) I must have had for 50 years or so. They're about a foot long and an inch wide. I have drilled one in various places to make impromptu pullers being too mean to buy proper ones.
24/10/2023 16:59:44 UTC
Ren - The Ed¹ said :-
These spoons as opposed to levers have been something of a revelation. They're thinner than my big ole' levers therefore taking up less of that precious tiny margin that allows you to get the tyre on. However, logically, they don't have the same level of leverage and therefore make your arms ache just that little more.

I am definitely liking the idea of heat shrink tubing. Like you say it'll get mashed in the process but it's cheap enough and easy to fit - good call.
Posted Image
25/10/2023 08:07:40 UTC
Upt'North ¹ said :-
It had too happen, it was just a matter of time, the boy has lost the plot....
"Cheap Enough".....not words I ever thought he'd usher.
I'm shocked and dismayed. Life will never be the same again.
Upt.
25/10/2023 08:48:25 UTC
Ren - The Ed¹ said :-
I'm sorry Upt', perhaps that comment should have come with a trigger warning. I do actually have a few pence here and there it's just that I don't like to spend it. Perhaps I should suggest Sharon pays for such things - I can live with scratching my own rims but if I were to scratch Sharon's then, well, I'm sure my life would never be the same again either.
26/10/2023 18:34:31 UTC
Upt'North ¹ said :-
Apology accepted, I know the miserly curmudgeon is just under the surface.
Upt.
27/10/2023 12:37:52 UTC

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