not sure about those hondas, but with bultacos, the steerer (stem) can be pressed out and swapped with little effort ( a hydrolic press). metrallas have a longer steerer tube than all of the moto-crossers with 35mm forks...but a simple swap of the steerer tube (out of the lower triple) allows for a seamless installation. i've been putting this change-over off for years simpley due to laziness. my 29.5mm front end is lighter than the 35mmm up-grade so i've been just riding around it's limitations ( a lttle flexy). with jonny b. talking about 1:30s on his cheater (honda 275) bike, i may have to the swap over to the "big" front end this year. and by the way, taper rollers are way over rated. the bearings in your triple don't make you go any faster...they just make you think you're tricker than thou.