H: Hubs, Wheels and Tyres Tyres

Bill Thomas

Bill Thomas

Well Known and Active Forum User
VOC Member
Confused , Bill. DSCN5745.JPG!!
 
Bill Thomas

Bill Thomas

Well Known and Active Forum User
VOC Member
I remember in the 80s, Not long ago was it ?,I got a tube for my Twin Special which has cast alloy wheels, They had a big fat washer, On the valve, And I did not like it because the tube to inside of the wheel was nice and snug, I was told I had to fit a tube, By the bloke that made the wheels, Can't remember what I did.
It's time I got that Beast on the back on the road, I have been playing with Comets to much !.
Comets are nice though, Now I am old and weak. Cheers Bill.
 
H

Hugo Myatt

Well Known and Active Forum User
VOC Member
flxible said:
This image was sent with one manufacturer's placement instructions.
If the manufacturers don't agree within and without their organizations why/how they specify product use, I guess it's not surprising the end users are left wondering what they had in mind.
I'm not remembering when double nuts became standard, but I seem to remember tubes had just a single nut back in my largely misspent youth.
Perhaps double nutting has been in use long enough the current employees are now young enough that no one really recalls the original reasoning.
Or maybe the legal team is somehow justifying their job.
Best-
George
View attachment 19507
Click to expand...
Like a good few in the club I have been fitting tubes for fifty years. It is only recently that they have come with two nuts. Originally the conical washer was fixed to the tube and with one nut only, usually knurled, outside the rim. The only difference I have found with new tubes supplied with two nuts is that the conical washer is loose which makes the fitting of the valve stem through the rim with the cover half in place a tricky business. I can not see the point of a having a conical washer if there is an awkwardly shaped nut between it and the rim.
 
Bill Thomas

Bill Thomas

Well Known and Active Forum User
VOC Member
The valves are not fitted in the tubes anywhere near as strong as they used to be, They need all the help we can give them. Cheers Bill.
 
D

druridge

Well Known and Active Forum User
VOC Member
flxible said:
Hi Bill, I'm catching up on my forum reading-
I've found tube installation to be a topic of perennial discussion whenever bench racing gets around to tube type tires.
The variety of tube mounting methods employed by both shops and individuals seems widely varied.
So maybe 1 or 2 years ago the lack of agreement on method finally lead me to make inquiries at Avon, Michelin, and one other manufacturer I'm not recalling.
I posted the answers online somewhere, but I guess it wasn't here, as it didn't turn up in a search.
Anyway, they all had basically the same answer-
1- curved washer on valve stem, (to protect stem to tube interface) then valve stem through rim
2- first nut used to hold valve stem tight to rim during tire mounting
3- after tire mounting, first nut is loosened approx. 5-8mm distance from the rim
4- second nut used to lock first nut in place
5- valve cap installed
One of the manufacturers said this for observing if the tire shifts on the rim.
In my experience it seems most rims are knurled to grip the tire bead, but that said, I have one set of Vin rims that are smooth at the bead location (Radaelli) while the other set (Akront) is knurled.
One of the manufacturers also mentioned installation as you suggested- one nut under rim and one nut over rim; saying this method was for off road guys who were using low air pressure, I believe the idea was if the tire were to shift, the tube stayed with the rim, which I suppose assumes lots of talc in use.
I also recall racers used to run a nut up against the valve cap, in an effort to keep valve cap in place, this to (hopefully) keep air in tube if valve stem spring was weak, I have no idea how wide spread this tactic was, whether it worked, or if it's still employed?
Best-
George
Click to expand...
My set up for regular off-road use is :
The curved washer (if provided) next to the tube inside the rim; one nut locked hand-tight up against the valve cap. I always use the 'heavy duty 'tubes now.
I use security bolts to reduce tyre creep front & rear, when I raced an 888cc (90bhp) Yamaha-Wasp outfit we used to add 4 self tapper screws through the alloy rims into the sidewall of the tyre(!)
The trail rides I do now result in dirty water almost permanently between the tyre and the tube, that must be a slippy interface?
When off-road, the idea is to have no nut tight on the rim so that if the tyre does move, and takes the tube with it, this is quickly spotted as an inclined valve stem and corrected. The alternative is a ripped out or snapped off valve stem (I've been there).
I start with pressures at 14psi (F), 12psi (R), cant remember what they are supposed to be when 'warm', but its more about allowing the tyre to mould to the surface than getting a sticky road tyre to temperature.
 
vibrac

vibrac

Well Known and Active Forum User
VOC Member
Well Bill I remember when there was only one nut I even remember when real rubber was available

as for trials tyres the only long distance trials tyre left is Pireli MT all the rest of the so called Trials tyres are for motorised pogo stick crew. and the rubber is so soft Angela could use them on her art courses for rubbing out.
And no self respecting Trail rider would use scrambles tyres we dont want to cut up the trails like herds of **** ramblers do we?
 
Last edited:
Bill Thomas

Bill Thomas

Well Known and Active Forum User
VOC Member
vibrac said:
Well Bill I remember when there was only one nut I even remember when real rubber was available

as for trials tyres the only long distance trials tyre left is Pireli MT all the rest of the so called Trials tyres are for motorised pogo stick crew. and the rubber is so soft Angela could use them on her art courses for rubbing out.
And no self respecting Trail rider would use scrambles tyres we dont want to cut up the trails like herds of **** ramblers do we?
Click to expand...
Well I am not sure of anything anymore !.
All I know is these Clowns are trying to kill us, What with tubes that loose air and sticking labels inside the tyre !, Just been told of another tube that has been damaged, He has been worrying about it for some time,
He said to someone, He will check it when he gets round to it, They said , Do it now !.
So he took the tyre off and is not happy !!.
Cheers Bill.
 
S

Sakura

Well Known and Active Forum User
Non-VOC Member
The washer and one nut SHOULD be on the INSIDE, And the one on the outside should be left loose so you could see tyre creep !.
Correct
And there is a train of thought that says the outside nut should actually be used as a locknut for the valve cap, which acts as a secondary seal.
 
Bill Thomas

Bill Thomas

Well Known and Active Forum User
VOC Member
Sakura said:
The washer and one nut SHOULD be on the INSIDE, And the one on the outside should be left loose so you could see tyre creep !.
Correct
And there is a train of thought that says the outside nut should actually be used as a locknut for the valve cap, which acts as a secondary seal.
Click to expand...
I agree with you but we are all looking for some proof, Anyway of telling us how you came to think this.
Cheers Bill.
 
Top