Tyre pressures

[johnnyXS]

My scoot was wobbling all over the place tonight and at one point I seriously thought I was going to completely lose it in50mph in a nasty crosswind . Popped into a garage to check the rear hub and thought I'd put some air in the tyres. I was staggered to find the rear only had 11psi !

I did a search but found there are lots of recommended pressures for tubeless but few for tubed tyres .
I'm interested in what pressures heavier riders use for sub 55mph ,general hacking about Town and Country lanes .
I'm 17.5 stone and using Mitchelin S1 tyres.

[CHRIS in MARGATE]

Innocenti always recommended 18 front and 28 rear increased to 32 if 2 up.
A good rule of thumb is 20/30

[Nigel. S]

According to 3rd edition service book from way back when: front 18lbs, rear 28lbs. 34lbs with pillion.

I don't go that high on rear. I'm 11.5 stone fully geared up, and wet through.

EDIT.. sorry, Chris snuck in as I was typing

[johnnyXS]

yes but those recommended tyre pressures are completely obsolete now.
Innocenti wrote that back in 1970 which is 45 years ago !

We now have vastly superior tyres, much heavier riders and scooters are considerably faster than Innocenti could ever have imagined .I bet the average Italian back in the 60's and 70's weighed less than 10 stone !
I was hoping that someone had done some recent testing and made some recommendations.
Perhaps we should be looking at recommended tyre pressures of modern twistngo scoots

[johnnyXS]

I did a little google searching online and was not surprised to find that Mark Broadhurst had written extensively on this very subject.
http://www.mbscooters.co.uk/info//mb-tech-articles/tyres-*-whats-right+247.html

Mark suggests increasing tyre pressures by 2psi at a time and testing. For heavier riders he suggests that you are likely to end up somewhere around 22-24psi front and 34-38psi rear for heavy riders or two up ! which is a lot more than the original Innocenti recommendations.

[Digger]

20/30 gets my vote.

[CHRIS in MARGATE]

Then he is wrong !. You try that high and see. I tried out of curiosity when someone mentioned it some years back. You start to lose grip as less of the tyre is in contact with the road surface.

[Gary Harwood]

I have been riding my S2 and S3 with SIP tubeless rims and Conti Twist tyres for several years now at 26psi front and 32 psi rear increased at the rear to 34 psi when I go on long runs fully loaded.

[johnnyXS]

Then he is wrong !. You try that high and see. I tried out of curiosity when someone mentioned it some years back. You start to lose grip as less of the tyre is in contact with the road surface.

Well that is what Mark suggests if you read his excellent article. Mark suggests that you start with the Innocenti recommendations and raise your pressures by 2lbs at a time and test it.

His suggestion is for heavier riders like me 17-18+ stone OR two up.

As a matter of interest how much do you weigh Chris ? and what tyres did you test the pressures on.?

[johnnyXS]

I have been riding my S2 and S3 with SIP tubeless rims and Conti Twist tyres for several years now at 26psi front and 32 psi rear increased at the rear to 34 psi when I go on long runs fully loaded.

they sound like some sensible pressures Gary. I won't embarrass you by asking your weight

I'm going to up my pressures today to 24 Front and 30 Rear and see how they feel . I only ride in the dry and max speed of my old gal is only 55mph I mostly cruise about 50mph and never go on rallys or extended motorway trips.

[johnnyXS]

20/30 gets my vote.

yes but what weight are you Digger ? your pressures are meaningless without your weight.
I am asking heavyweight riders ( above 17 stone) what pressures they run on.
cheers
Johnny

[CHRIS in MARGATE]

110 Kgs and S1's on tubeless.
Not my favourite tyres to be honest. Had Continental Navigators on before and much preferred them.

MB has expressed his opinion; it doesn't make him right.
I have expressed my opinion; that too doesn't make me right.
I and many others have carried out our "research" so we all know what we feel comfortable with.

[johnnyXS]

110 Kgs and S1's on tubeless.
Not my favourite tyres to be honest. Had Continental Navigators on before and much preferred them.

MB has expressed his opinion; it doesn't make him right.
I have expressed my opinion; that too doesn't make me right.
I and many others have carried out our "research" so we all know what we feel comfortable with.

Hey Chris I'm not challenging your opinion or saying that you are wrong . turns out you are the same weight as me and use the same tyres so your experience is actually more valuable to me than Marks in this instance which is why I was hoping to get some feedback like yours.
Thanks for the imput its appreciated

[burnside]

On my tubed S1s I run with 20/32 and on my tubeless Shwalbe Powertracks I run 24/38. I weigh around 100kg.

[Warkton Tornado No.1]

Hopefully, without treading on anybody’s toes, I feel almost compelled to comment as there is a safety issue @ stake here.

Firstly, although road racing may be considered fairly polarised, it is @ the forefront as far as ensuring that a full frame Lambretta handles dynamically to the best possible standards.

Although neither my son nor I are shabby riders, we still advocated 17 PSI front & 27 PSI back, even with SIP rimmed tubeless tyres up to a couple of years ago. Many years ago, Ray Kemp advised that as he reasoned that racing elevated the temperature of the tyres & thus the pressure.

However, not only are neither of us ‘current racers’ but the track is non-stop flat out racing.

Add to that the fact that anti-dive front set-ups change the game further, it would be good to get feedback from ‘current racers’, IMO.

Finally, nonetheless, in the absence of any other advice from arguably the best known riders of S III Lambrettas, it would appear to my way of thinking that the standard 18 PSI/28 PSI solo would still seem to apply. That is what I use with S1’s but they are horrible, twitchy tyres so my advice is somewhat unendorsed by that fact.

I hope to have helped, though…..

[ToBoldlyGo]

Don't you ever check your tyre pressures Johnny?

We all know that riding soft tyres is like trying to steer a blancmange and hard tyres don't have any feel to them. So that optimum point is going to be where it doesn't effect the handling either way. My own take on it is that everyone is different and you should adjust your tyre pressure accordingly.

[Digger]

20/30 gets my vote.

yes but what weight are you Digger ? your pressures are meaningless without your weight.
I am asking heavyweight riders ( above 17 stone) what pressures they run on.
cheers
Johnny

85 kilos - on and off a race track: 20/30. ( 13st 6lb or thereabouts.)

[johnnyXS]

Don't you ever check your tyre pressures Johnny?

.

ha ha it was my very first ride this year (the scoot has been laid up since last October .)
I knew the tyres would need checking and a top up but never thought brand new tubes would lose so much pressure over Winter.

[johnnyXS]

[

85 kilos - on and off a race track: 20/30. ( 13st 6lb or thereabouts.)

blimey digger! ...I dream of being 13 stone . I've been 17 stone for 20+ years now despite trying to lose weight.

[burnside]

[

85 kilos - on and off a race track: 20/30. ( 13st 6lb or thereabouts.)

blimey digger! ...I dream of being 13 stone . I've been 17 stone for 20+ years now despite trying to lose weight.

The XS doesn't stand for Extra Small then