Archive of BMW Motorrad Club Cape (2006 - 2019)

What about the tube tyre bikes?  650.  700, 800 GS...

Well these bikes tyres are not tubeless tyres.

The snotty plugs cannot be used.

Any slime, sludge or canned spray stuff  is limited to Dubbeltjie pin holes only.

Tube pinches or punctures from rocks or  nails will not be helped by sludge or canned stuff.

Never were and never will.

And no glue/patch will stick to the  tube after the sludge runs out the hole, so you can through away the tube if you used slime, sludge or spray.

True story.

The answer is to carry a 17 inch rear tube and a 21 inch front tube, sorry the differences are too big to use a single generic tube.

When you have a puncture, please do not hold up the entire ride by patching the tube on the road.

Remove the wheel, remove the tube and replace it after you have found what caused the hole and if it was a sharps in the tyre, then remove that.

Put your spare tube in the tyre and off you go.

You can repair the punctured tube later, at leisure without disrupting everyone else's ride any more than you have to.

That's the trade off you have to live with having a better, more zippy bike.

The 650 and 800 series has to have the wheel off then the tube out and replaced- it's a ball-ache of note and you probably will not find a boxer bike rider over keen or eager to help you as this was one reason why they went for tubeless wheeled bikes.

Sadly, to be self sufficient you have to lug two tubes around, not just one.

Andy, for me, your input is always appreciated. I also agree that we, as a group, carry way too many duplicate items when doing a club ride. For my F800GS I carry spare F & B tubes as well as tools and tyre levers. The levers are the small ones which probably won't work too well if I ever need to use them in an emergency so I should look at getting the longer ones. I also carry a tubeless repair kit just in case somebody on one of my rides has a puncture and there is nobody else with plugs around.

I prefer to carry my own stuff so it at least looks like I've made an effort and not relying on somebody else to bail me out every time. I must be honest I do lack mechanical knowledge and rely on wiser people for advice and assistance in a break down situation.

Interesting.

Used slime a lot on my mountain bike with great success on normal thorn punctures and once on my old Honda.

I bought my Dakkie with a can of slime in the tankbag. Lekka this is sommer a pressure can as well.  For more than a year I cart this with me and had no use for it.  THEN, Marinda and I went on a tar trip to Umthata.  Mike asked why we do not take some tubes and compressor with. Naah.. we are on tar.

And then about 10km before ronnies sex shop I saw Marinda weave more than normal and asked her to stop.  Lo and behold, rear deflating fast.

Out with the slime can.  It pumped the tyre hard enough to reach Ladysmith.  The big thing with these slime fixes is that one MUST TREAT IT AS A TEMP FIX.  If the puncture is on the running surface a slow rotate of the wheel will spread the goo and cover the hole.  It is also good to lean the bike as much as possible to either side and rotate the wheel about 5 rounds to cover the sides as well.  This is only required if you are not sure where the leak are.  That day I was too lazy and only did the running surface of the wheel.  I just assumed the puncture will be there.  

We headed for Ladysmith. About 5 odd km past Ronnies I noticed the waving again.  We turned around and stopped at Ronnies to assess the problem.  Ok long story short.  I rode to Ladysmith and purchased a tube, compressor and tractor tyrelever. (Got it cut in half and now just shorter than standard ones.  ) 

When I removed the tube I saw the puncture was actually halfway up the sidewall. Now I was be!@#$ because I did not spread the goo to the sides.  A little bit did get to the hole but not enough to stop the leak. Ok, my lazyness costed me a lot of time and money.

My conclusion.

I will always carry a pressure can of goo.  It is a convenient rescue.  NOT A PERMANENT SOLUTION but a quick resque.  I will just remember to do the sides as well if I do not see the object causing the problem.

Adie

Andy, this has always been one of my biggest fears riding alone. When I bought my 1st GSA I was given 2 spare tyres and 2 cans of the inflatible foam stuff. Fortunately I have never had a need to use either.

But to the point. Seeing that you seem to have a lot of knowledge in this area, would you be willing to run a "breakdown" workshop for club members? I have a very hands-on person, and don't mind doing things around the garage myself. The knowledge gained will somewhere down the road become handy.

GROOT asseblief.

Also, where would be a good place to buy the short tyre levers?

Cheers,

Leon

very insightful, Andy, thanks for posting.

I too, have have good success with goo, which will fix some, but NOT all, (tubeless) punctures. And a few I know feel the same, funny enough, we do not stock it anymore (unsure why not), but I can be a useful addition to a puncture repair kit.

And personal and customer feedback - experience;  stretching a 1" smaller tube to fit a 1" bigger rim can cause the valve (seat) to tear, since it is now under undue 'tension', so we think the lesser evil is say to stuff a 19" (front) tube into a 17" rim (with the caveat this is a get-you-home fix only), and whilst there is more 'tube' than needed, there is LESS stress on the valve - what we advise our customers, anyway!

(The 'gap' between the tubed 800GSA which is 21" front and 17" rear is admittedly a big gap, so probably best to carry correct size tubes front and rear...)

We would therefore recommend carrying a FRONT tube as a spare when 19" and 17" combo, ditto when 21" and 18" combo, obviously bikes (rare) with same-size front and rear (dual 17" wheels), this is less of an issue...

Love your articles!

Cheers, Chris & team

Thats excellent advice Chris and important to note feedback from other riders.

Thanks for your comment, I trust others will take your advice.

Some tips for the tubed bikes:

Getting the wheel off

A centre stand will make your life immeasurably easier (some 650s come without one). Apparently you can remove a wheel without it, but if you have a bike with a chain, do you not lube it often? How do you lube it without a centre stand? I tried it once, got pissed off and invested in a centre stand the next week.

The next time you replace your tyre, don't be lazy and get Trac-Mac to do the whole thing for you. Remove the wheel and your tyre in the comfort of your garage, taking note of every tool you use in the process. This will build confidence in your abilities for the day you do get a puncture and will highlight nicely if you are missing any tools.

The f650.com website includes some really nice instructions on rear wheel removal (which is the more tricky one, but, as Murphy's Law and the law of physics has it, would be the one most likely to get a puncture) for the 650. I'll repeat the instructions here, in case that website disappears:

1. Undo main axle bolt. It looks like this:

A hex spanner is easiest, i.e. the one with the round hole that looks sort of like this (though we have the ones with the normal spanner bit on the one side and the round bit on the other side):

I usually just put the spanner around the nut and then step on it. No elbow-grease required. Initially the nut will undo without the Axle rotating, but very quickly you will need to hold the head of the axle on the left-hand side, while you undo the nut on the right-hand side.

2. Take note of your chain tension settings before removal. You can see the numbers and lines in the little window on both sides of the bike (they must both be the same, otherwise your wheel will be skew).

I think the 800 (or at least the latest models) has a way of removing the wheel without messing with the chain tension settings.

3. Loosen the Allen keys that control the chain sag adjustors. They sit here on both sides of the bike:

Some say to remember the number of turns as you loosen the Allen keys. Lance and I have almost universally forgotten to check tension settings or check the number of turns when loosening the Allen keys, so it's not a train smash. You can adjust your chain tension until it looks ok again when you put the wheel back on. If you worry about it, you can have it checked by a mechanic when out of the sticks.

4. Pull out the axle (from the left-hand side). The wheel will drop and tends to jam if you don’t have anything under it, so get a wedge or ask a buddy to hold it. NB tip: during your test-at-home how-to-remove-wheel session or when you have a new tyre fitted at a tyre fitment place, for the love of all that's holy, ask them to liberally cover the axle with grease. They will stare at you blankly and tell you that this is not required to remove the axle. When you are in the sticks, trying to hammer out the axle with a rock for a good 30 minutes (as we had to do with Ilse's 650), you will wish for that grease. The f650 website recommends greasing for a different reason: if your wheel-bearings fail and the axle doesn’t have enough grease, the wheel bearing inner race(s) can weld themselves to the axle. Sounds expensive.

5. Remove the chain from the sprocket. Without the axle and with the chain tension adjustor loosened (or even with the axle in, but just the chain tension loosened), you are able to push the wheel forward until the chain is loose. Remove it from the sprocket teeth by lifting it up and off and pushing it to the right of the sprocket.

6. Remove the wheel by wheeling it backwards. This is a tricky bit, as there are many parts you don't want to snag or damage, i.e. brake disc, brake calipers and chain. Don't use the brakes when the wheel is off. It will make it difficult to get the brake disc back into place between the brake pads and mucks around with your hydraulic pressure (if mountain bikes are anything to go by).

There's all sorts of other loose bits that come out of the wheel in the centre (if you don't take them out first). Just take note of where they were. It's like an easy puzzle to put it back together again.

Breaking the bead

First things first: the wheel will be on the ground (if you don't have a jammer-lappie). You don't want to hurt your brake disc, so don't place the wheel with this side on the ground.

Lance and I have workshop-sized bead-breakers, though we hardly ever use them. We have found it far easier to use Lance's 800's side-stand to break the bead of my tyre. We would place my tyre on the ground. Lance, standing next to his bike, would lean it sideways so that the side-stand is in the air. I would wedge the tyre under his side-stand, making sure the side-stand foot was resting on the tyre just next to the rim. Lance would then lean the ful weight of the bike onto the side-stand and, hence, onto the edge of the tyre right by the rim. It works like magic. You work your way around the tyre until you have broken the bead right around.

The reason we still take the levers along? The 650 side-stand cannot be used to break a bead, because it has a funny little metal loop rather than a mini square foot like the 800. Though if Lance gets a puncture, we may still use his bike to break his own tyre's bead. We will cross that bridge when we get there. Meanwhile, I'm usually the one getting punctures for some strange reason that I need to take up with the universe.

Removing the tyre

You only need to get one side of the tyre up and over the rim in order to make space to install a tube. Many state that the small tyre levers are ok for removing the tyre. Our experience is that the longer workshop-sized ones make life much, much easier. Though we still carry 2 smaller ones along with the 2 longer ones (we had bought the smaller ones first and got fed up with them pretty quickly, which is why we now have 4). We always use the longer levers first and then use the small ones as wedges to make sure the tyre does not slip back while we work our way around with the longer levers. So, in general, we use all 4 levers, though you can get away with two. Tip: where-ever you are trying to get the tyre up and over the rim with a lever, have someone press down with their knee on the opposite side of the tyre, so that you're not fighting the bead on that side, i.e. the tyre will sit in the V of the rim, which gives you a bit more levering room on the opposite side.

You can fit a larger tube into a smaller tyre, but try not to do the reverse (though it is possible)

My 650GS has a non-standard front wheel, which means that both Lance (800GSA) and I have 17-inch rear and 21-inch front tyres. His rear tyre is just slightly wider than mine. We therefore pack two tubes between the two of us: one for the 21-inch front and a 17-inch one that would fit Lance's wider tyre. As stated by Chris, it is better to stuff a wider and/or larger diameter tube into a smaller tyre than vice versa. Thanks to my many punctures, I have used Lance's wider rear tube at least twice and had no particular issues. I would keep them in and replace only at the next puncture.

During one ride, when I pinched our 17-inch tube, we stuffed a 21-inch front into my 17-inch rear tyre. This must be viewed as a very temporary fix. Do not ride fast on it. I did, which meant that it had sprung a slow leak by the next day. We managed to get home by inflating every now and then. So, yes, a 21-inch front tube can be used for a 17-inch rear if you are really, really stuck. Try not to inflate it too much. It has to inflate quite far beyond its designed spec if it is to fill a rear tyre when it was meant for the narrower front.

Getting the damn tube in

More tricky than it sounds. I usually do it, as my hands are the smallest. Getting the valve through the hole is the most painful (literally - squashed hands) process of the whole lot. The front wheel is apparently even worse... Get a valve puller. This gadget screws into the tube valve and has a piece of wire coming from it, so that you can pull the valve through the hole rather than trying to push it through within the cramped confines of the tyre. Though, as we've found out to our chagrin, it does not work with all tube's valves. Some seem to be slightly smaller or larger. Anyhow, it's not a train smash and you can survive without the valve puller. You'll just be swearing more.

Inflation and getting the tyre back on the bead

Getting a tyre back onto the bead means inflating it until it sits flush on the rim. Some tyres make a satisfying popping sound when this happens. A knobbly tyre is far easier to get back onto the bead than any road-oriented tyres, thanks to the softer rubber. We've had to pump up Gerhard's rear tyre to some crazy pressure (I think it was 4-5 bar) before it reseated (at least we had a compressor!). My tyres, very knobbly, reseated when pumped with a stock-standard hand-held small bicycle pump. Lance and I did not have a compressor for a while and had to make do with a bicycle pump. We'd take it in turns doing 200 pumps each! It's taxing, but can be done. If you have a tubed bike, most likely you have a chain and chain lube. Spray some chain lube onto the edges of the tyre, to help it reseat on the rim. Or use dishwashing liquid. Or any other lube-ish, mushy stuff.

Installing the wheel

The front is pretty simple. With the rear, it helps to open the brake pads a bit with a lever of some sort (one of the tyre levers helps). There's all sorts of technical how-to-put-the-rear-wheel-back notes on the f650.com website, but it makes it seem more scary and complicated than it actually is. Basically: you saw where everything was before you took out the wheel, now put it all back. You'll find out pretty quickly that the brake calipers are meant to go around the brake disc, etc. Installing the rear wheel is the most fiddly part of the whole business and usually required a buddy to hold stuff in place as you get the wheel back to where it should be and push the axle through, but can be done on your lonesome (again - just more swearing involved). Only NB bit: do not tighten the axle nut yet. You can put it on, but do not tighten. That only happens after you've adjusted your chain tension. Also, if it is tight, you cannot shove the wheel all the way forward in order to get enough slack on the chain to get the chain back onto the sprocket.

Adjust chain tension

This is for the 650s. The 800s can have a tea-party at this stage (I wonder if the older models require chain tension adjustment?). Your wheel is now installed, but because you have not tightened the nut, you can still move it backwards and forwards. Those little Allen keys on both sides of the bike are used to adjust the chain tension.

Hopefully you've remembered your chain adjustment settings from a check beforehand (in the little windows on both sides of the bike). If you forgot to check, you'll just have to fiddle with the Allen keys until the chain tension looks ok (the numbers/lines in the window will move backwards and forwards as adjusted - make sure both sides are the same). Remember to have either you or a buddy keep pressing the rear wheel forward (the axle nut is not yet fastened and the wheel tends to shift backwards, which mucks around with your actual chain tension settings). Once the setting is correct, you can tighten the axle nut.

Generally, the setting is ok, if you take the bottom bit of the chain and press it upwards and it is sort of parallel with the swingarm. Like so:

There are fancier checks (e.g. shouldn't be more than 25-30mm of play or some-such), but the parallel indicative test has worked for me.

When you have the correct setting, tighten the axle nut. Only then do you tighten the Allen keys yet again (they do not adjust the chain settings when tightened further, because the axle nut is now locked in place). We almost universally forget this last step. Most mechanics seem to forget as well. Eventually the Allen keys rattle almost completely loose and that bit of metal at the end of the swingarm, called the supporting plate, starts rattling - hopefully you'll hear the noise and decide to investigate. The supporting plate:

It is better to have a chain that is too slack rather than too tight. You can always have a mechanic check it when you arrive home if you are unsure. Note: a chain does not have the same tension everywhere. Spin the wheel around until you find where it appears that the chain is tightest. Adjust your tension here, otherwise, if you adjust the chain to what appears to be on the correct setting when you are actually adjusting it on a loose section, it will be too tight on its tightest section.

Random note: we've found with the 650 that even when we've adjusted the chain tension to what looks like a perfect setting when the bike's on its centre stand, it seems to tighten up massively once on its side stand and/or once ridden. Tip: Therefore adjust the chain tension to something that may look a little too loose and check whether it's ok when riding (remember to tighten the axle nut before checking chain tension by riding!). If the chain tension doesn't look too good (i.e. too tight), loosen the axle nut and start playing around with the Allen keys again, while remembering to keep the rear wheel pressed forward.

Getting clean!

Lance now packs some gardener gloves. I still rough it. I have a perfectly good solution to getting my hands clean without soap: (1) Find a patch of sand/dirt (the sandier, the better) and scrub hands thoroughly with this miracle substance. It scrubs off all grease. Why do you think people use sand to wash dishes if water isn't around? (2) Suck up some water into your mouth from your water bladder (if you are in the sticks, you should have water...). (3) Gently release water from your mouth - you now have a human tap that doesn't waste as much water as having a buddy pouring a bottle of water over your hands, because you can control the flow. (4) Wash the sand/dirt from your hands - the grease stuff should all be gone thanks to the sand wash. Voila!

Edit

I left out two bits of information in the above:

1) Before removing the rear wheel, you have to remove your ABS sensor to avoid damage to said device (I don't have ABS, but for some reason I still have the sensor). See below image for rough approximation of what you're looking for. Ignore the cable to the left of that in the highlighted circle - it's an odd mod (couldn't find a nice, clean image on Google). Essentially just loosen the ABS sensor, pull it out and let it hang out of harm's way.

2) When putting your wheel back onto your rim, remember to install it so that it rotates in the correct direction! Usually there's an arrow somewhere on the tyre showing you which way it should rotate.

Great writeup Zanie.  Getting clean:

1. scrap gloves (old riding gloves for e.g. because you can use them if your main gloves get wet) also protect your hands when doing rough/hard work.
2. I now carry a small pack of wet wipes - the alcohol on them cleans your hands very nicely.  If you don't have any, just  ride with Alf - he uses them to clean his visor.

Wonderful write-up Zanie! As always very entertaining and full of good advice.....

Only one small addition.......on the off chance Lance gets a puncture - lol

I've broken the bead on my own with my 800 with the side stand - just put the 800 on it's main stand - remove the back wheel - then do it exactly as you've described above. Works like a charm on the back wheel - with the front wheel you're probably going to need a buddy to help.... 

Zanie is the absolute expert in this field, she has had more punctures than the whole club combined. Tx. for the detailed description on this subject.

I carry 3 small pieces of insertion rubber (100 X 100 mm) to protect the rim from the tire lever when removing and replacing the tire. For sidewall cuts I have packed tire gators, Fortunately the need to use has not arrived and hopefully never will. Anybody else have experience with gators? How about the actual application of the patch ? My nemesis.

Lance and I also carry some rim savers, but when you're in the bundus you tend to just go "stuff it," after fiddling with them for a bit. I already have quite a large smiley on my front rim, so protecting it from some scratches seems superfluous. Anyway, even if my bike looked pristine (it doesn't), and was younger than a decade (it isn't), the rapidly-increasing mileage has put it into a bracket where resale value is not something I'm going to worry about.

I've tried patching. The patch seemed to hold beautifully (lots of experience with bicycle tyres - key is to wait for the glue to dry completely, which basically no-one ever seems to do), but we discovered that there were all sorts of other holes from snakebites, thanks to riding for a short bit on a completely flat tyre. Basically: don't bother with patches unless in the comfort of your own home and you are sure there is just one hole that needs fixing and not a whole armada. Still, patches will come in handy if you run out of spare tubes, so I'd still recommend carrying them.

We do not carry gators as far as I know, which is perhaps an oversight. We've never had sidewall cuts before. To the universe: don't go getting any ideas. You've been rather nice to me lately. Keep it up.

I have successfully used plastic cards - a loyalty card like a Clicks Card, to serve as a gator on someone tyre and glue over the slit in the sidewall held there by the tube served well and tube never got to push through the tyre.

so for me, a club card (or other such card) is my emergency gator

I've recently migrated from an 800 to a 1200, but am still riding around with my tube puncture kit. I'm about to go and buy a tubeless kit but I see they contain fancy new plugs, like a figure 8 rubber as opposed to the 'snotty' plugs that I've used before on cars.

Are these new plugs any better than the 'snottys' and how easy are they to insert into the tyre, compared to the snottys?

Like many of you, I've watched the You-tube videos and seen how easy it looks. Recently I assisted a friend with a puncture on his Fortuner and pushing that snotty into the tyre took a lot of elbow grease! I was surprised how much effort it took. We had to remove the wheel so we could apply enough pressure from the top, But we got it fixed.

Another question: The two-in-one tool that comes in these repair kits has the rasp up at the top of the shaft and the insertion tool at the bottom. My GS12 has low-profile road tyres (60%) and it looks to me like one could ram the tool into the rim, if one were too enthusiastic with the rasping to prepare the hole for the plug?

I already have a few bombs, an applicator, a right-angle adaptor, valve removal tool and insulation for the bombs. I would also wear my glove when applying the bomb, just to be sure! So my intention is to buy just what I need to add to my current kit, as opposed to buying the complete kit.

Any advice on the best tools and plugs will be highly appreciated.

Trevor,

Great to see you going about getting yourself ready for traveling far from the next Wimpy, by making sure you are self sufficient.

Wish more motorcyclists had the same attitude.

I have both the gooey rope and the rubber kidney plugs, I find it is actually quick n easy to repair a puncture by plugging once you have the hang of it. I learned by offering to help others fix theirs. By the time I go my first puncture I had made most of my i mistake sn someone else's tyre.

80%+ punctures ar ein the rear wheel.

And this is easier, depending on the tyre make. But 5 minutes, end-to-end is about the right time it takes from fining the cause to removing the cause and getting ready to depart again.

 For your C02 canisters, this R75.oo valve cock is a sure fire winner.

Buy along with canisters at any cycle shop.

allows you to control the flow.

Its a good idea to sacrifice a canister in the interest of leaning how to use one of these effectively.

Trevor, carry a spare tube, light duty, not heavy duty.

Choose a 19' tube, you can fit it into both tyres if needed. This is for that sidewall damage or a hole too large for those plugs to be effective.

Just wondering if anyone has successfully used a tube in an R1200GS/A rear tyre? My reason for asking is because I have read a number of mixed reports. Some say it works but others say it does not because of the off-centre valve position on the rear rim. This apparently results in the tube tearing at the base of the valve due to the stress from the misalignment of the valve. Maybe a factor in Andy saying do not use a heavy duty tube?

Thanks for your input Andy. I have one of those CO2 applicators in my kit. I've used them before on mountain bikes, but never on a motorcycle tyre. I know those bombs get really cold, hence my remark about the gloves.

Still not sure if that rasp tool would go deep enough to hit the inside of the rim on my wheel? I'll ask Chris at Flying Brick. In the interests of saving space and having multi-purpose tools I'd rather have one tool that can do both jobs, provided it works well. Otherwise I'll pack two separate tools into my kit, one rasp and one insertion tool

You reckon I should ditch my can of foam? I've successfully inflated tubeless car tyres with foam before, so I'm hanging on to it for now.

As for the plugs, I'll put both types into my kit.

And I'll offer to assist friends with their punctures, like you did, to get some practice in :)

The all-in-one rasp, applicator is good to go and will not damage your rim inside, unless you try real hard. I use it for the rerson it takes less space and it has served well.

Trevor, if you only do one intelligent thing still in 2016, it should be to ditch foam and sludge.

Great for 450cc or less, or bicycle.

But for a motorcycle,it will only cause you grief.

foam or sludge in a tube means you will never repair the puncture as no adhesive can stick to a rubber surface once it is sludge/foam coated.

The snake oil salesman will tyr beguile you to keep it handy, but he won't be around when you use it.

repair your puncture- its easy

I riding friend and buddy, Steve went out into the Tankwa this past weekend with some friends he and noticed pressure loss, rear tyre.

The reason - knobblies had come off the new tyre.

Why? how?- not speed or aggressive riding related, he is milder than French mustard in his riding style.

However, Steve had a spare tube in his kit.

Fantastic!!

So with a little help, when On Call failed to respond, he could effect self rescue.

Well done Steve. 

You put your trip back together amd could limp home under your own steam. And that's what makes the journey a success.

errr... 40 degrees heat could not have made your temper any better....

Hi Andy - Steve is a customer of ours (Steve, from the Deep South, right?).

Anyways, what tyre failed, always keen to hear, irrespective of whether it cam from us or not?

thanks!

Chris & Team

I have tried using that sludge before without success, I still have a can of Finilec dating back to the early 1980's, free to whoever wants it. Should all else fail insert the tube that you have been schlepping around for the past 151,0K kilo's, , remember the rubber does go off after a time so do replace, annually, I'd say.

I was watching TopGear Polar Expedition today and saw a strange thing

They couldn't get the Hilux tyre to expand to seal with the rim using a compressor until they put lighter fluid inside the tyre.

They then lit the fluid and hey presto the tyre expanded to seal with the rim.

Now I have to ask, is this tv or does it actually work? 

In warmer climes you can do it with petrol.  I have not seen it done myself, but believe it works.  It's like when you put a match to the mouth of an empty meths bottle and it goes "woof".

David, we have used this method out in the sticks with the Heidinau tyre which is a very tight fit.

There is a clip on Youtube where the eyr is over-dosed with Deodorant and the tyre blows, injuring the closer person.

Neverthelss, not something I will try myself ever again.

The case with Steve in Ceres,...... if you have a tube, it will eventually expand and pop the tyre onto the bead.

So  I am not sure why they?>>>

dunno.