TOPIC:

Hello,

My front tyre is tired.
I used the Brigestone spitfire s11 100/90-19 for years but think to replace it for a coker firestone deluxe 4.00-19

Will i have troubles ?

Best,
Fox

A 4.00 tire on the front will slow steering a good bit.  It might even rub the fender, but this is just a guess.  It will also upset speedo calibration due to the larger diameter.  Just my opinion, but I'd look for a smaller tire, something like a 100 or 3.25.