Rear Tyre Selection Advice / Frustration

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Rob H
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Rear Tyre Selection Advice / Frustration

Postby Rob H » Sat Jun 16, 2018 10:57 am

Had to remove the back wheel and found it almost impossible due to the tyre (which is an old Avon Road Runner 4.00 x 18) jamming between the brake shoes and swing arm. Only got it out by letting down completely. Refitting the rear wheel was not possible with all in place. Removed the left shock, still no good, removed the brake shoes, still no good (catching on the fixed pivot) ended up having to remove the rear bevel!

This tyre is ultimately to be replaced and was looking at the Bridgestone BT45 as dual compound so should give good mileage touring.

The point being is, if I had a rear puncture with the existing tyre it would have been pretty much unfixable by myself at the side of the road which is unacceptable.

Any advice on what new rear tyre to use which is narrow enough to allow easy removal and refitment of the rear wheel without dismantling everything?

regs
R

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Re: Rear Tyre Selection Advice / Frustration

Postby barryh » Sat Jun 16, 2018 11:56 am

Had to remove the back wheel and found it almost impossible due to the tyre (which is an old Avon Road Runner 4.00 x 18) jamming between the brake shoes and swing arm. Only got it out by letting down completely. Refitting the rear wheel was not possible with all in place. Removed the left shock, still no good, removed the brake shoes, still no good (catching on the fixed pivot) ended up having to remove the rear bevel!

All mostly normal but you should have been able to get it back in again deflated without removing the final drive. Try a thin sheet of plastic up against the brakes shoes to help it slide in. I have a large mud flap so I need take the whole mudguard off.

A bit out of date now but some years back I had a go at listing the widths that various people had measured. Manufacturers data for tyre width is not necessarily directly comparable with each other as the mounted width will vary according to what rim size it was measured on. I would be interested to know what inflated width the Avon was that caused you so much difficulty. Anything up to 120 mm should have been doable.
Tire Sizes.JPG
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Jon K
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Re: Rear Tyre Selection Advice / Frustration

Postby Jon K » Sat Jun 16, 2018 12:56 pm

I think, if you hang the back of the bike over a kerb or something you can drop the wheel out downwards rather than pulling it out backwards.

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Re: Rear Tyre Selection Advice / Frustration

Postby CharlieVictor » Sat Jun 16, 2018 4:01 pm

Gee, never has that problem. And I had installed and removed a 130x80x18!
How do you do it?

You certainly need a lift as the rear end must be higher than what the center stand allows to remove the wheel without touching at the fender.

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Re: Rear Tyre Selection Advice / Frustration

Postby SteveD » Sat Jun 16, 2018 6:16 pm

Remove the rear guard and it's easy enough.

On centre stand, seat off, two bolts at subframe crossover, two bolts at the rear subframe, disconnect the taillight loom. 5 minutes..
Cheers, Steve.
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Re: Rear Tyre Selection Advice / Frustration

Postby Peter_T » Sat Jun 16, 2018 6:32 pm

Hi - I have just changed the rear tyre on my 1978 R80/7. The bike has a standard Krauser pannier rack (one piece with rack). My preferred aproach:

1. Remove rear mudguard complete with rear light, indicators and mudflap - 4 * 10mm nuts and one multi-pin connector. This is easier than the equivalent task on a XS750/850 with a hinged rear mudguard!

2. Deflate tyre by removing valve core.

3. Remove wheel spindle nut and release tension on clamp bolt on the left hand side, then withdraw wheel spindle.

4. Move wheel as far to the left as possible and withdraw to the rear past the brake shoes - the old tyre was a well worn Avon Roadrider 4.00 * 18".

The new tyre was a replacement Avon Roadrider also a 4.00 * 18" - the standard size.

I normally inflate the tyre after fitting to ensure the tyre is seated properly but then accept that I have to deflate it again to fit the wheel past the brake shoes before re-inflating the tyre.

I rate 1970's airheads, as one of the few bikes that I can readily fix a puncture at the side of the road myself. My fellow riding colleagues think I'm mad because I insist on changing my own tyres to keep up my skills come the day (night?) that I need them miles from the nearest bike shop. My pals who ride R1200GS and K1600s couldn't even remove the wheels as BMW do not provide tool kits for the task.

Part of the tyre changing task is to rebalance the wheel and I've been very impressed with the wheel balancer tool that I bought from Marc Parnes in the US, great quality and designed to fit our wheels with tapered roller bearings:

http://www.marcparnes.com/BMW_Motorcycl ... r.htm#BM17

BM wheel balancer.JPG
The local bike shop can dynamically balance the balance wheels but only does so to with 5g and they struggle to tension the taper roller wheel bearings on their machine. After some practice, I can now achieve excellent static balance better than the 5g. The chap that runs my local bike shop is joining the rest of us retired folk and the shop is set to close in the autumn.

Good luck with the wheel changing, best regards - Peter
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Re: Rear Tyre Selection Advice / Frustration

Postby windmill john » Sun Jun 17, 2018 8:25 am

Remove the rear guard and it's easy enough.

On centre stand, seat off, two bolts at subframe crossover, two bolts at the rear subframe, disconnect the taillight loom. 5 minutes..

+ 1
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Re: Rear Tyre Selection Advice / Frustration

Postby Rob Frankhamr » Sun Jun 17, 2018 11:10 am

Remove the rear guard and it's easy enough.

On centre stand, seat off, two bolts at subframe crossover, two bolts at the rear subframe, disconnect the taillight loom. 5 minutes..

+ 1
+1

You can make removing the rear mudguard much easier by welding or otherwise securing the reinforcing plates That go under the mudguard to the heads of the bolts. No more forcing your hand between tyre and mudguard insert the bolt and hold it still while doing up the nut...

Rob
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Re: Rear Tyre Selection Advice / Frustration

Postby barryh » Sun Jun 17, 2018 12:34 pm


You can make removing the rear mudguard much easier by welding or otherwise securing the reinforcing plates That go under the mudguard to the heads of the bolts. No more forcing your hand between tyre and mudguard insert the bolt and hold it still while doing up the nut...

Sound advice. I've lost some skin to that activity.

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Re: Rear Tyre Selection Advice / Frustration

Postby bwprice100 » Sun Jun 17, 2018 1:00 pm

I'm bit confused with this, I have an 81 R80TIC and don't have to remove anything to get the back wheel out.

I don't have to deflate the tyre either.

Brian
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Re: Rear Tyre Selection Advice / Frustration

Postby CaptAirhead » Sun Jun 17, 2018 3:03 pm

The back wheel came off my '79 R80/7 TIC no bother with Michelin Macadams fitted. Lets see how it goes back on when I get the BT45's fitted.
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Re: Rear Tyre Selection Advice / Frustration

Postby CharlieVictor » Sun Jun 17, 2018 6:13 pm

Remove the rear guard and it's easy enough.

On centre stand, seat off, two bolts at subframe crossover, two bolts at the rear subframe, disconnect the taillight loom. 5 minutes..

+ 1
I beg to disagree, especially on an old bike being run every day where those parts are hardly ever removed.

There has to be, there is, an easier way. Remove the wheel by removing the wheel, not taking apart the bike. #-o
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Re: Rear Tyre Selection Advice / Frustration

Postby Rob H » Sun Jun 17, 2018 7:01 pm

A bit out of date now but some years back I had a go at listing the widths that various people had measured. Manufacturers data for tyre width is not necessarily directly comparable with each other as the mounted width will vary according to what rim size it was measured on. I would be interested to know what inflated width the Avon was that caused you so much difficulty. Anything up to 120 mm should have been doable.

Tire Sizes.JPG
[/quote]

Rear tyre width is 122mm, bike was on a raised workbench with the rear section removed so the wheel could drop straight down.

The plastic sheet sounds a good tip. Will try that as the wheel will have to come off again in the near future

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Re: Rear Tyre Selection Advice / Frustration

Postby barryh » Sun Jun 17, 2018 9:21 pm

Rear tyre width is 122mm, bike was on a raised workbench with the rear section removed so the wheel could drop straight down.

The plastic sheet sounds a good tip. Will try that as the wheel will have to come off again in the near future

122 mm is certainly at the more difficult end of things but I think you'll find the plastic sheet helps.

You have to love the way BMW describes removal of the rear wheel in the riders handbook:

removal and installation of the rear wheel can only be described as childs play thanks to the use of shaft drive ...


There is no mention of dropping the wheel down or removal of the mud guard or any difficulty at all. The man that wrote those words had obviously never actually done it.

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Re: Rear Tyre Selection Advice / Frustration

Postby Memphis Twin » Sun Jun 17, 2018 11:13 pm

Which is obviously why BMW developed the single-sided swinging arm for later airheads.

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Re: Rear Tyre Selection Advice / Frustration

Postby Roy Gavin » Mon Jun 18, 2018 4:30 am

Actually, on my mono G/S the muffler has to come off to remove the wheel, whereas Mac 50's and Pilot Actives come out of the twin shock R 75/7 no bother at all.
I always have the bike secured by a couple of ratchet straps from the rafters when working on it when it is on the stand, perhaps that might hold it a bit higher. If you need more hieght the front tire can be deflated or the front wheel removed with a jack under the sump and the bike gently lowered as required.
At the tire dealer it is a two man operation , with bike on centre stand one tilts the bike over until the other can remove the wheel.

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Re: Rear Tyre Selection Advice / Frustration

Postby Memphis Twin » Mon Jun 18, 2018 8:47 am

Actually, on my mono G/S the muffler has to come off to remove the wheel, whereas Mac 50's and Pilot Actives come out of the twin shock R 75/7 no bother at all.
On my R65 Mono I can get the rear wheel out without removing the silencer.

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Re: Rear Tyre Selection Advice / Frustration

Postby andymcg » Tue Jun 19, 2018 12:25 am

Hi - I have just changed the rear tyre on my 1978 R80/7. The bike has a standard Krauser pannier rack (one piece with rack). My preferred aproach:

1. Remove rear mudguard complete with rear light, indicators and mudflap - 4 * 10mm nuts and one multi-pin connector. This is easier than the equivalent task on a XS750/850 with a hinged rear mudguard!

2. Deflate tyre by removing valve core.

3. Remove wheel spindle nut and release tension on clamp bolt on the left hand side, then withdraw wheel spindle.

4. Move wheel as far to the left as possible and withdraw to the rear past the brake shoes - the old tyre was a well worn Avon Roadrider 4.00 * 18".

The new tyre was a replacement Avon Roadrider also a 4.00 * 18" - the standard size.

I normally inflate the tyre after fitting to ensure the tyre is seated properly but then accept that I have to deflate it again to fit the wheel past the brake shoes before re-inflating the tyre.

I rate 1970's airheads, as one of the few bikes that I can readily fix a puncture at the side of the road myself. My fellow riding colleagues think I'm mad because I insist on changing my own tyres to keep up my skills come the day (night?) that I need them miles from the nearest bike shop. My pals who ride R1200GS and K1600s couldn't even remove the wheels as BMW do not provide tool kits for the task.

Part of the tyre changing task is to rebalance the wheel and I've been very impressed with the wheel balancer tool that I bought from Marc Parnes in the US, great quality and designed to fit our wheels with tapered roller bearings:

http://www.marcparnes.com/BMW_Motorcycl ... r.htm#BM17

BM wheel balancer.JPG
The local bike shop can dynamically balance the balance wheels but only does so to with 5g and they struggle to tension the taper roller wheel bearings on their machine. After some practice, I can now achieve excellent static balance better than the 5g. The chap that runs my local bike shop is joining the rest of us retired folk and the shop is set to close in the autumn.

Good luck with the wheel changing, best regards - Peter
I haven’t (yet) tried to change bike tyres myself. I take the wheels to our local tyre dealer who has been able to match online prices and fits for free.
I have however had him use the www.dynabeads.co.uk way of balancing the wheels. It. Seems to work. If I was fitting tryres myself I would use it.
Does anyone else use these ceramic beads in the tyre to balance their wheels?


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Re: Rear Tyre Selection Advice / Frustration

Postby SteveD » Tue Jun 19, 2018 3:17 am

At the tire dealer it is a two man operation , with bike on centre stand one tilts the bike over until the other can remove the wheel.
That was how I used to do it. Once the axle was out, I'd stand on the throttle side and lean the bike (on cs) onto me. Then using my left hand, jiggle the wheel out to the rear. The mud flap was always a problem and this method eventually caused it damage and was why I moved to the removal of the guard and flap. Much easier, less awkward and probably a li'l bit oh&s too
Cheers, Steve.
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Re: Rear Tyre Selection Advice / Frustration

Postby Rob Frankhamr » Tue Jun 19, 2018 10:43 am


I haven’t (yet) tried to change bike tyres myself. I take the wheels to our local tyre dealer who has been able to match online prices and fits for free.
I have however had him use the www.dynabeads.co.uk way of balancing the wheels. It. Seems to work. If I was fitting tryres myself I would use it.
Does anyone else use these ceramic beads in the tyre to balance their wheels?


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I have to say I'd take a great deal of convincing. I've read the description of how it works (or rather is supposed to work) and, to my mind, there are a number of glaring holes in the physics.

I have to say that similar claims were made by the sellers of pre-injected tyre sealants like 'Slime' (not sure the claims were ever made 'officially' by the manufacturers) ...i.e. that they worked to balance a tyre by self distribution around the circumference of the carcase... My understanding is that these claims were dropped when they were threatened with prosecution for false advertising because there was no evidence to show that it had any such effect.

Needless to say, I'll be sticking with conventional balance weights...

Rob
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Re: Rear Tyre Selection Advice / Frustration

Postby John Marshall » Tue Jun 19, 2018 9:30 pm

I tie centre stand to exhaust cross tube, remove front wheel, remove rear axle,tip bike up,remove rear wheel,put bike back down on axle stands under the silencer ends.The fact that my centre stand is wearing at the feet end makes me worry about a collapse. Hardest bit is trying to get a twin ATE wheel back in. When was a bit younger I could tip the bike onto my hip and wiggle the wheel out but I have given up with this. I also tried some stepped blocks of wood alternately rocking the bike till they were under the stand.
John

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Re: Rear Tyre Selection Advice / Frustration

Postby IanG » Tue Jun 19, 2018 9:50 pm


I have to say I'd take a great deal of convincing. I've read the description of how it works (or rather is supposed to work) and, to my mind, there are a number of glaring holes in the physics.

I have to say that similar claims were made by the sellers of pre-injected tyre sealants like 'Slime' (not sure the claims were ever made 'officially' by the manufacturers) ...i.e. that they worked to balance a tyre by self distribution around the circumference of the carcase... My understanding is that these claims were dropped when they were threatened with prosecution for false advertising because there was no evidence to show that it had any such effect.

Needless to say, I'll be sticking with conventional balance weights...

Rob


I was sceptical too but decided to give the Dyna beads a try. They do sound like snake oil but I'm sufficiently happy with them that I now have them in three bikes including my R100. I've had it over 100mph (on the Isle of Man m'lord) and it runs smoothly with no tyre vibration.

Ian
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