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I have a new Brompton Kevlar (Green) label tyre I am trying to fit to the rear wheel of my L6. Getting it on the rim is fine but inflating it so it sits evenly all the way around is proving impossible. Every time I try to slowly inflate the tyre checking the beading all the way around the rim is seating, one portion of the circumference is failing to rise out sufficiently giving the tyre an egg profile/ or flattened appearance as it is held in which is no good! The bead at this portion appears not to be able to rise up slightly onto the seating part of the internal profile of the rim. I have tried numerous times to try to lift the tyre out as I inflate but to no avail.
My conclusion is the internal diameter of the tyre is too small as 270-300 degrees of the tyre seats fine but a short part of the cirunference is of the tyre is being held in for some reason. So I suspected the tyre diameter/circumference is too small. I measured the internal diamter at 346mm at several places around the 360 degrees of the tyre. If the internal diameter had a true 349mm diameter then I believe the tyre would seat properly.
I have fitted many many many tyres and tubes over the years from Contis, Michelin, Bontrager, Specialised, Vittoria and never ONCE have I had this problem. Any one else experienced it and how did you solve it?
The cynic in me thinks that Brompton or it's manufacturer of it's tyres is trying to save every miserable Yen in trying to make the tyre with an internal diameter as small as possible which means it is so tight on the internal rim or just not large enough making it impossible to seat the tyre easily and quickly .
Advice?
Contact Brompton?
Take tyre back to bike shop?
(Old tyre was fine except that one of the bars in the wall had started to split so I needed to change it really).
TIA.
I have a new Brompton Kevlar (Green) label tyre I am trying to fit to the rear wheel of my L6. Getting it on the rim is fine but inflating it so it sits evenly all the way around is proving impossible. Every time I try to slowly inflate the tyre checking the beading all the way around the rim is seating, one portion of the circumference is failing to rise out sufficiently giving the tyre an egg profile/ or flattened appearance as it is held in which is no good! The bead at this portion appears not to be able to rise up slightly onto the seating part of the internal profile of the rim. I have tried numerous times to try to lift the tyre out as I inflate but to no avail.
My conclusion is the internal diameter of the tyre is too small as 270-300 degrees of the tyre seats fine but a short part of the cirunference is of the tyre is being held in for some reason. So I suspected the tyre diameter/circumference is too small. I measured the internal diamter at 346mm at several places around the 360 degrees of the tyre. If the internal diameter had a true 349mm diameter then I believe the tyre would seat properly.
I have fitted many many many tyres and tubes over the years from Contis, Michelin, Bontrager, Specialised, Vittoria and never ONCE have I had this problem. Any one else experienced it and how did you solve it?
The cynic in me thinks that Brompton or it's manufacturer of it's tyres is trying to save every miserable Yen in trying to make the tyre with an internal diameter as small as possible which means it is so tight on the internal rim or just not large enough making it impossible to seat the tyre easily and quickly .
Advice?
Contact Brompton?
Take tyre back to bike shop?
(Old tyre was fine except that one of the bars in the wall had started to split so I needed to change it really).
TIA.