After reading in the Classic trials press, the Pre 65 Scotish allows tubless type tyres to be used with a tube in their regulations....but not without.

Could someone enlighten me with the logic behind this and also do tubless tyres run without a tube... offer any proven advantage and if so what.

Thanks

There is no huge advantage which is why I guess they allow it. Advantage is that there is a wider choice of tyre manufacturer and that tyres are more easily available as tubeless. No real disadvantage as far as I am aware

I dont know of a descernable advantage other than a wider choice.

I'd just be grateful for an entry

Oh well fingers crossed

"Tubeless tyres fitted with a tube on a tubeless rim MUST BE DECLARED and maybe checked. Inner tubes must be fitted - NO 'O' RINGS to be fitted.

Hubs to be Pre-65 design only. No Bultaco, Fantic, Ossa Yamha, etc.

No twin-leading shoe brakes"

The rationale is simple, Dunlop and Michelin have ceased production of tube-type trials tyres, there will be no more, that effectively leaves Mitas and IRC as the sole manufacturer.

The bikes used before 1965 did not have tubeless tyres or tubeless rims, so the Scottish does not allow a tubeless arrangement.

On another front, there will be spot checks on machines during the event - penalty will be harsh, EXCLUSION, I would take that as a very serious warning guys, the organisers are obviously getting fed up with cheating!!!

Don't think about switching on to your spare trick wheels during the event, you never know where cameras are picking you off!!!

Big John

Edited December 12, 200718 yr by Big John

As well as not changing to their trick wheels it might be wise for bikes not to think about having several different riders aboard during the event this year?

As well as not changing to their trick wheels it might be wise for bikes not to think about having several different riders aboard during the event this year?

or riders using more than 1 bike....

seen riders on same make and model but different bike..

Edited December 12, 200718 yr by totalshell

"Tubeless tyres fitted with a tube on a tubeless rim MUST BE DECLARED and maybe checked. Inner tubes must be fitted - NO 'O' RINGS to be fitted.

Hubs to be Pre-65 design only. No Bultaco, Fantic, Ossa Yamha, etc.

No twin-leading shoe brakes"

The rationale is simple, Dunlop and Michelin have ceased production of tube-type trials tyres, there will be no more, that effectively leaves Mitas and IRC as the sole manufacturer.

The bikes used before 1965 did not have tubeless tyres or tubeless rims, so the Scottish does not allow a tubeless arrangement.

On another front, there will be spot checks on machines during the event - penalty will be harsh, EXCLUSION, I would take that as a very serious warning guys, the organisers are obviously getting fed up with cheating!!!

Don't think about switching on to your spare trick wheels during the event, you never know where cameras are picking you off!!!

Big John

Big John

Do you know how the organisers will treat tubed or tubeless tyres running without tubes but having multiple air balls fitted. This has been done recently to remove the risk of punctures. Notron

I would imagine they would remove your balls!!

From where ever you choose.

Big John

Do you know how the organisers will treat tubed or tubeless tyres running without tubes but having multiple air balls fitted. This has been done recently to remove the risk of punctures. Notron

Hi Not Ron,

In answer to your question, I don't know. I could try to find out of course. Is that similar to a mousse in any way? I personally have not seen these fitted, interesting one!

The Pre65 tyre problem has arisen purely from the tyre manufacturers making a commercial decision to cease tube type cover production and to have old bikes fitted with Cota type rear wheels I guess the organisers are trying to avoid.

Big John

As we all know tubeless tyres were not even dreamed about in pre 1965 times, the Club I am a member of (since 1981,) brought this very rule in about five or six years ago, at that time tube tyres were readily available from top manufacturers, As all Pre 65 riders who compete on rocky going know INPACT punctures are a big item, more so with the Rigids and Pre Unit machines, When time is involved in a trial we all know that taking a wheel out, repair or replace tube, wheel back in takes a LOT more time than a quick repair to a tubeless tyre. Plus forget the Cubs, James etc if you know the risk of a puncture on a big machine is less then you are going to take some better lines in sections going over large rocks rather than going round them so in my mind thats two reasons for keeping tubes in tyres.

so you have to use a tube in a rear tubeless tyre/rim what a complete waste of time !

if these guys need a tube tyre, they will find a tube tyre rather than not ride.

why don't they just ban tubeless rims & tyres FULL STOP !

and as for the NO O RING thing i have not used one in a tubeless rear for the last 2 years,

just cut a valve stem out of a tube and a thick layer of wickes silicon sealant around the rim.

too many rules to bend, and would the organisers exclude one or two of the top names ,

IMHO NO !!!

so you have to use a tube in a rear tubeless tyre/rim what a complete waste of time !

if these guys need a tube tyre, they will find a tube tyre rather than not ride.

why don't they just ban tubeless rims & tyres FULL STOP !

and as for the NO O RING thing i have not used one in a tubeless rear for the last 2 years,

just cut a valve stem out of a tube and a thick layer of wickes silicon sealant around the rim.

too many rules to bend, and would the organisers exclude one or two of the top names ,

IMHO NO !!!

I had trouble getting a tube tyre for my bike so ended up fitting a tubless tyre with a tube. That is why this rule has been made.

When I posted this topic, I must admit it was meant in an almost cynical manner. I had been talking to a very good friend who was docked marks in the Pre 65 Scottish for having a tube less tyre Without a tube. He was understandably peeved so much so I believe he called it a day and headed south straight away. He supports trials up and down the country riding a big triumph and has been involved with trials for some forty odd years . He is one of the most genuine and principled people who competes in pre 65 trials which is riddled with double standards and rule bending. He is the last person I would label a cheat , which has been remarked here towards people who have built and ride bikes with tubless tyres.

I have noted with interest the reasons why they should not be allowed of which I find a little curious if not whimsical.

" A wider range of tyres " to " Easier to fix a puncture " and best of all " On a big bike you can take a better line and hit the big rocks harder "

I know full well you cannot have one rule for one etc etc , but the above person is over Sixty riding one of the few genuine big bikes the Pre 65 scene is now crying out for and his tubless tyre offers how much of an advantage ....... very little if at all.

When I hear and read about all the other mischievous goings on I get the feeling the people in charge are quite selective in which bikes they check and perhaps turn a blind eye to the wrong riders.

Happy New Year

Frenchie

Hi Guy's

I have just spent a bit of time checking out if you can still get tubed trials tyres,(Has I need Some) and have found at least six companys who can supply them.( even 400x19).

These are besides the cheapo ones from the middle east, One company who sells trials bits are offering Pirelli back tyres for under

I had trouble getting a tube tyre for my bike so ended up fitting a tubless tyre with a tube. That is why this rule has been made.

i did not know you had such influence north of the border !