MP5 and flats

[Socalbiker]

Hi,
Wondering if anyone else having recurring flat problems?
 Using a cheap tire [26x1.5] and tube @40pis  I've had a couple of flats. Went to a better quality &  bigger tire [26x1.9] at 50 psi, major blow out in less than a mile both times. At a loss for what to try next, stay with 1.5 or go with bigger tire but limit pressure?

Another question, what pressure is the GM rim rated for?

thanks

[Bikemad]

A good quality tyre fitted with a "slime filled" self-sealing inner tube will greatly reduce the need for puncture repairs:



I have Slime tubes fitted to all of my Magic Pies and I have not had to repair a puncture on any of them yet.

Although, I did have one tyre that went completely flat several months ago after the bike had been stood unused for a long time. I blew the tyre up and then listened carefully all around the tyre, and I eventually discovered air escaping through a tiny hole in the centre of the tread.
I decided to raise the wheel off the ground and spin it at full throttle so that the centrifugal force would distribute the slime more evenly around the tube, and it quickly stopped the air leak. 

Months later, the same tyre is still holding pressure, but I now check it regularly by hand and occasionally top up the air pressure if the tyre feels soft.

I don't know what pressure the rims are rated for, but they should easily be able to withstand the recommended tyre pressure for the tyres that are fitted to them. 
I initially blow all my tyres up to the maximum pressure stated on the tyre to ensure they are seated correctly onto the rim before letting air out until the desired running pressure is achieved.

A major blow out can only occur if the tyre is severely damaged by riding over a sharp object or by pinching the sidewalls against the rim by impacting the tyre against kerbs or sharp edges of deep potholes etc..

I run 26" x 2.35" Schwalbe Crazy Bob tyres on this bike:



These tyres are rated for 45~65 PSI, but I tend to run them at ~30 PSI as the bike is mainly used off road.
Do not consider fitting wide tyres if your frame is too narrow at the front of the chainstays, as the actual width of my tyres @ 60PSI was just over 61.5mm (not including the little tiny strands left over from the moulding process).

I also have a slightly narrower 26" X 2.30" Kenda Kiniption tyre fitted to the rear MP4 currently installed in my wheelie machine:



The only guaranteed way of avoiding punctures altogether is to fit solid tyres.

Alan