Author Topic: Tyre pressures  (Read 2036 times)

Offline BrianS

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Tyre pressures
« on: 03.01. 2017 10:02 »
I had an email reply this morning from Ashley Vowles at Avon recommending tyre pressures for my 1955 BSA A10 650cc Golden Flash (swinging arm model).

For the Avon Safety Mileage MkII rear tyre 3.50x19 he recommends 30 psi

For the Avon Speedmaster 3.25x19 front he recommends 26psi.

Both tubed type.

He recommends increasing those by 1-2psi to carry a pillion.

Brian
1955 BSA A10 Golden Flash
Exeter, Devon, UK

Online bsa-bill

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Re: Tyre pressures
« Reply #1 on: 03.01. 2017 11:33 »
yes I agree with those pressures, when I first rebuilt the Flash I followed the BSA book - not good.
Modern tyres (even the old names) require higher pressures, think I read they are made differently now.
Tubes are something I have a thing about, rear has never had a problem but the front always has a very slow leak, like the  three tubes I've put in are all porous, and yes I have checked the spokes and changed the tyre, could be I'm just a crap tyre fitter of course
All the best - Bill
1961 Flash - stock, reliable, steady, fantastic for shopping
1959 Rocket Gold Flash - blinged and tarted up  would have seizure if taken to  Tesco

Offline dave55

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Re: Tyre pressures
« Reply #2 on: 03.01. 2017 16:00 »
http://www.a7a10.net/forum/index.php?topic=1538.0

It was the above thread that lead me to this forum and glad I did too  *smile*
Having bought my A10 in sept last year and it being the first time on a Brit bike for over 40 year I thought  *eek* WTF have I bought ! had already checked tyre psi and correct to manual that came with the bike but it was all over the road and crap cornering, googled the tyre pressures for the bike and up came the above thread, straight to the garage and pumped up the tyres to said pressures and a pump or 2 for the wife on the back and Hey Presto it was a different bike to ride !
BSA Bantam D7 175  1961
BSA A10 650 Golden Flash 1955 Plunger
Suzuki GSX1400 2003

Offline Rgs-Bill

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Re: Tyre pressures
« Reply #3 on: 03.01. 2017 23:42 »
   WOW ! ! ! !  My Haynes manual says, 18 pounds front , 20 pounds rear, from what I read here, that has to be way too low ! !

       Good old Haynes manual, 47 to 62 A-7 and A-10 bikes.  Just another one of the many miss info`s in Haynes. ! ! ! !
U S of A
N.W. Corner, Seattle 
1962 RGS
78 YEARS OLD
Still Kick Starting My Motor (9 TO 1)
Although getting a bit tougher to do ! !

Offline Rocket Racer

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Re: Tyre pressures
« Reply #4 on: 04.01. 2017 02:27 »
   WOW ! ! ! !  My Haynes manual says, 18 pounds front , 20 pounds rear, from what I read here, that has to be way too low ! !

       Good old Haynes manual, 47 to 62 A-7 and A-10 bikes.  Just another one of the many miss info`s in Haynes. ! ! ! !

Bill,
 its not that Haynes was wrong for the tyres of the day (back in the sixties), but that todays tyres require much higher pressures even if we are choosing old school patterns. 25-30lbs is a good starting point. The new tyres are made with modern compounds and with modern methods irrespective of the tread still being circa 1950
Tim
A good rider periodically checks all nuts and bolts with a spanner to see that they are tight - Instruction Manual for BSA B series, p46, para 2.
New Zealand

Offline Tomcat

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Re: Tyre pressures
« Reply #5 on: 04.01. 2017 06:38 »
[quote author=bsa-bill
Tubes are something I have a thing about, rear has never had a problem but the front always has a very slow leak, like the  three tubes I've put in are all porous, and yes I have checked the spokes and changed the tyre, could be I'm just a crap tyre fitter of course

I bought some pure rubber tubes and they leak. Apparently this is a good feature. As I always fit new tubes to new tyres, next tubes will not be pure rubber...

And Haynes manuals should not be relied upon, just good to have the specs all in one place
Cheeers TC
'48 A7 '59 SR '74 850 Commando TDM900

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Re: Tyre pressures
« Reply #6 on: 04.01. 2017 13:00 »
I like a little more in my Avon AM26 Road Riders. 32 in front 36 in back. If it's wet I drop 2 out of each.
Cheers
'51 A7 plunger, '57 A7SS now A10CR,  '83 CB1100F, 88 FXST .
Australia
Muskys Plunger A7

Offline BrianS

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Re: Tyre pressures
« Reply #7 on: 04.01. 2017 13:14 »
I like a little more in my Avon AM26 Road Riders. 32 in front 36 in back. If it's wet I drop 2 out of each.
Cheers

Funnily enough those are the pressures I guessed at before I heard back from Avon and, with two up, they seemed to work just fine!

Probably a tad OTT for going solo though.
1955 BSA A10 Golden Flash
Exeter, Devon, UK

Online chaterlea25

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Re: Tyre pressures
« Reply #8 on: 04.01. 2017 17:56 »
Hi All
Quote
next tubes will not be pure rubber..
Tomcat,
I only use quality branded, Michelin, Metzeler, or Continental tubes
All these seem to lose pressure over time
It makes you check the pressures are correct regularly  *good3*

Back in 2001 I had a really nasty "Off" when a synthetic rubber tube split in the front wheel *warn*
I think a bit of chrome peeled and punctured the tube ?? but instead of losing pressure over time
it split along a 6in. length *pull hair out*

John

1961 Super Rocket
1963 RGS (ongoing)

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Re: Tyre pressures
« Reply #9 on: 04.01. 2017 20:08 »
I wouldn't even consider using a butyl tube after seeing the way they tear. I just put up with the rubber.

Offline BSA_54A10

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Re: Tyre pressures
« Reply #10 on: 05.01. 2017 09:25 »
They usually only split when they have been overinflated.
Bike Beesa
Trevor

Offline hdawson

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Re: Tyre pressures
« Reply #11 on: 05.01. 2017 10:36 »
32/36 seem rather high Musky.You must have a good back.
I usually run around 30 both ends but will give it a  shot.
Cheers.

61 BSA Super Rocket (cafe).
51 Matchless G9 Clubman.
81 Suzuki GSX 750 ES.
02 Triumph Sprint.

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Re: Tyre pressures
« Reply #12 on: 05.01. 2017 10:52 »
G'day HD.
Ha, my back is rooted (L4 L5 S1 fused). I've tried lower pressures and they feel (to me) a little washy. With the pressure I run the Avon Road Riders just fall into corners, I luv'em.
Cheers
'51 A7 plunger, '57 A7SS now A10CR,  '83 CB1100F, 88 FXST .
Australia
Muskys Plunger A7

Offline duTch

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Re: Tyre pressures
« Reply #13 on: 05.01. 2017 14:23 »

 I also work on running ~28/~30 and it's fine, but as my tubes also rapidly lose pressure, I sometimes go a bit extra, so it's a couple of weeks before they get down to 15, whereby they feel a bit 'buckety' (I don't check them every outing- most days @ short notice)

 The good thing about adding air, is they feel like new tyres again *woo* *woo*
Started building in about 1977/8 a on average '52 A10 -built from bits 'n pieces never resto intended -maybe 'personalised'
Have a '74 850T Moto Guzzi since '92-best thing I ever bought doesn't need a kickstart 'cos it bump starts sooooooooo(mostly) easy
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Offline Slymo

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Re: Tyre pressures
« Reply #14 on: 28.03. 2019 01:21 »
Just discovered mine were flat, the only tell tale was that the back squealed on braking. Filled them up to 22 and 30 and the only difference was it was a little bit more feel through the bars. Avons front and back. My old RE Bullet just stops lying down round corners when the tyres are low but no such indicator on the SR.
NZ