Tyre pressures

[johnnyXS]

no its XS650 my other baby

[Digger]

[

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.

I used to be about that but a run-in with the Big C sorted that in short order....

[johnnyXS]

blimey Digger glad to hear you came through ok. That has to be the one thing we all dread to hear. its about time that big pharma did a little more research into why we get it and preventing it rather than developing expensive medicines to treat it that make them obscene amounts of money ..

I was diagnosed type 2 Diabetic last xmas. I used to watch people on TV having their feet and legs removed and thought why on earth didn't they do something about their sugar intake when they knew the risks.! Now I'm one of them ...stuffing sugar in my gob every day then watching my blood sugar levels go into 2 figures .....one day I'll wake up and take this seriously before its too late.

carpe diem matey

[Digger]

Thanks Johnny, got the 5 year all-clear just last week...

Seize the moment - yes indeed!

[johnnyXS]

Fantastic news ! very pleased for you buddy.
What are you going to do to celebrate ? I've been planning on doing a bike tour when circumstances permit. I've been planning it for 2 years. One day....

[Digger]

Well I've already done a couple of seasons doing the BSSO racing. Rode to the Dordogne on one of Lambretta's last year.

Expanded the Italian love affair with a MotoGuzzi Griso.

[Rich Oswald]

20/30 gets my vote.

+1 but I am 11 stone and that's using Mitas MC20's (32 in rear with camping gear on).

Rich'

[citydaz]

im 100kgs and put in 20/30 on my conti twists

[coaster]

.....I was diagnosed type 2 Diabetic last xmas. I used to watch people on TV having their feet and legs removed and thought why on earth didn't they do something about their sugar intake when they knew the risks.! Now I'm one of them ...stuffing sugar in my gob every day then watching my blood sugar levels go into 2 figures .....one day I'll wake up and take this seriously before its too late.

Off topic I know but 2 guys I work with have been following the 8 Week Blood Sugar Diet, it's a book by Dr Michael Mosely and both of them have managed to reverse their type 2 diabeties. You can download it onto a Kindle or tablet for about £2.50.

Colin

[HxPaul]

I think that once you are diagnosed as a type 2 diabetic you have it for life.My brother was diagnosed with the disease and saw the hospital nutritionalist who gave him a diet sheet.He stuck to this diet and the weight fell off him,at the end of his diet he was tested again by the specialist and he could not find a trace of it.Unfortunately over the years his weight crept up and he is now injecting himself 3 times a day with insulin.
By the way,I'm 16 stones and use s1's and the pressure is 20psi front and 30psi rear,going up to 34psi rear if I carry a passenger.

[johnnyXS]

thanks for your suggestions Coilin & Paul.
I was diagnosed back in January after becoming seriously unwell.
My Doctor completly missed all my pre-diabetic symptoms for the past 8 years and the support I received from the local Diabetic clinic was an absolute scandal considering this is a life threatening condition.

I was given a 5x year old NHS leaflet recommeding I go on a high carbohydrate diet ....and no nutritional advice whatsoever so I had to do my own research and treat myself.

I got my blood sugar levels down from 28m/mmol/L to within the reference range within 26 days after considerable online research.

Although for the first 2-3 months I had frequent Hypoglycemic episodes, (very low blood sugar levels ), I seem to be free of those too now so I am well into remission.

Diabetes Type 2 needen't be a lifelong condition it all depends on what is causing the high blood sugar levels. Sometimes it can be simply an inflamed Pancreas which causes too little Insulin to be produced or it can be a problem at cellular level, Insulin resistance.

The only way to be sure is to insist on a referral to an Endocrinologist and then insist on a full blood panel. By doing this, I found out that not only did I have Diabetes, I also had Hypertension, Adrenal fatigue and a macro Prolactinoma which in simple terms is a benigh brain tumor on the Pituitary gland . This causes the Pituitary to produce too much prolactin which in turn reduces your Testosterone to rock bottom levels. The Pituitary gland is called the master contoller because it effects every hormone producing gland in the body besides other vital functions.

This together with my 20 year long battle with Hypothyroidism goes a long way to explaining why I've felt like shite for the past 10 years or so. bluddy quacks

[Northumbrian]

I tried to ring SIP to ask their recommendations,

I run SIP Tubeless with Michelin S83 Classics

Their. telephone numbers on their site dont work and had no reply to my Email. Hmmmm

[Fast n Furious]

The make and tyre rating also has an effect on the required pressure.
Tyres with stiffer side walls can generally use a little less pressure.
Continuous high speed riding will generate a lot of heat further raising the pressure. which can be a good thing in the right circumstances.
The question is arbitrary really because it all depends on the scope of use.
I limit my continuous high speed road riding to no more than about 20 miles a thrash, simply because the rear tyre gets to hand burning temperatures and needs to cool down before I dare go any further. ( I need a cig break anyway)
It's a slighly different situation on the race track because you accept the consequences that come with track racing. A bit more diligence is needed for the road IMO.

It's a very overlooked subject though. I'm constantly nudging my fellow club members about their obvious underinflated tyres. It's usually the first thing I notice as they pull into the pub carpark every week.
One of them recently ended up in hospital after a 50MPH front blowout left him sprawled across the A64. He was however riding a Vethspa so this may have had some bearing on the matter?

[Warkton Tornado No.1]

The make and tyre rating also has an effect on the required pressure.
Tyres with stiffer side walls can generally use a little less pressure.
Continuous high speed riding will generate a lot of heat further raising the pressure. which can be a good thing in the right circumstances.
The question is arbitrary really because it all depends on the scope of use.
I limit my continuous high speed road riding to no more than about 20 miles a thrash, simply because the rear tyre gets to hand burning temperatures and needs to cool down before I dare go any further. ( I need a cig break anyway)
It's a slighly different situation on the race track because you accept the consequences that come with track racing. A bit more diligence is needed for the road IMO.

It's a very overlooked subject though. I'm constantly nudging my fellow club members about their obvious underinflated tyres. It's usually the first thing I notice as they pull into the pub carpark every week.
One of them recently ended up in hospital after a 50MPH front blowout left him sprawled across the A64. He was however riding a Vethspa so this may have had some bearing on the matter?

I have nothing significant to add to this long debate, but was wondering if you re-check the pressures when you make your enforced 'hand hot' stops?

For the record, are you running tubeless?

Just for completeness, when the BSSO approved tubeless rims for racing (which to me seems a no-brainer in not adopting) there were a number of top racers that resisted, choosing to continue with tubed tyres with the addition of a lining between tyre & tube made from cut up inner tubes. They still got punctures & I was not surprised. Rubber creeps & exasperates heat build up IMO.

[coaster]

......I limit my continuous high speed road riding to no more than about 20 miles a thrash, simply because the rear tyre gets to hand burning temperatures and needs to cool down before I dare go any further. ( I need a cig break anyway)

That;s good practice, I sometimes remember to do that too

[missing lynx]

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

I have to disagree the dimensions and the volume of air in the tyre haven't changed. I run sip tubeless rims with 20 psi in the front and 30psi in the back upping it to 34psi if I'm fully loaded or carrying a passenger. I remember when the Schwable problem happened and the advised putting a minimum of 36psi in the tyres my front end was like a pogo stick and the scooters was almost unrideble. I have friends with classic cars and motorbikes and they still put the same psi in as the manual say so why should scooters be any different?

[missing lynx]

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.

I would take what MB says about tyres with a pinch of Salt he was the one to prommote Schwable tyres as the best scooter tyres ever made!!

[Fast n Furious]

I dont think the old Swalbe issue was an isolated one. I used to use them years ago and never had an issue personally.
Most of the issues that I see with tubeless tyres can be traced back to poor fitting.
We all know that they are a pain to fit and the tyre beads are easily damaged by tyre levers which inevitably damage the rims as well.
I prefer to drop the new tyre into a large bowl of hot water for 5 mins to soften it up, then dry it off with a clean rag and hand fit the tyre with lashings and lashings of tyre soap without using any tools.
Sometimes, it can be a challenge to get the beads to sit on the rims, making initial inflation a bit frustrating. A ratchet strap around the circumference of the tyre usually sorts this out.

It's not just Lambretta wheels that are challenging here. Some modern twist and go "Liqour sickles" are just as bad.
The worst examples of tyre fitting I have ever seen were done by local motorcycle dealerships. Some of which, were outright dangerous.
If you don't have a trusted fitting source, or the skills to do it properly yourself, then it's probably best to keep using your split rim tubed wheels.

[citydaz]

im 100kgs and put in 20/30 on my conti twists

I ve lost some weight during lockdown.
Now weigh 78kg but still use 20/30 psi on my conti twists!

[Fast n Furious]

The make and tyre rating also has an effect on the required pressure.
Tyres with stiffer side walls can generally use a little less pressure.
Continuous high speed riding will generate a lot of heat further raising the pressure. which can be a good thing in the right circumstances.
The question is arbitrary really because it all depends on the scope of use.
I limit my continuous high speed road riding to no more than about 20 miles a thrash, simply because the rear tyre gets to hand burning temperatures and needs to cool down before I dare go any further. ( I need a cig break anyway)
It's a slighly different situation on the race track because you accept the consequences that come with track racing. A bit more diligence is needed for the road IMO.

It's a very overlooked subject though. I'm constantly nudging my fellow club members about their obvious underinflated tyres. It's usually the first thing I notice as they pull into the pub carpark every week.
One of them recently ended up in hospital after a 50MPH front blowout left him sprawled across the A64. He was however riding a Vethspa so this may have had some bearing on the matter?

I have nothing significant to add to this long debate, but was wondering if you re-check the pressures when you make your enforced 'hand hot' stops?

For the record, are you running tubeless?

Just for completeness, when the BSSO approved tubeless rims for racing (which to me seems a no-brainer in not adopting) there were a number of top racers that resisted, choosing to continue with tubed tyres with the addition of a lining between tyre & tube made from cut up inner tubes. They still got punctures & I was not surprised. Rubber creeps & exasperates heat build up IMO.

I did once check the hot tyre pressures but it was years ago and I no longer recall what the increase was.
On my own machines I use the AF 3" tubeless rim on the rear with a 10/120/90 section tyre. (Modified engine casings, rear mudguard and rear of frame are needed). This tyre has only 3mm difference in diameter compared to the 12/120/70 setup I have on the front. The scoot therefore sits up 1" higher. Cornering is great fun, with zero exhaust groundings.
For giggles.... I used to park the bike up with a couple of bricks under the stand feet with the front wheel up against the pub wall. Start it up, drop it into 4th and rev it out and watch the cold rear tyre inrease in diameter by about 30mm
This is also a tetchy way of determining how good your rear wheel balance is, albeit a bit scarey when you find out that it's crap and tries jumping off the stand.