High-G FJR Junkie!
Join Date: Mar 2015
Location: Rolling Prairie, Ind
I think a lot of things contribute here, tires (dual or single compounds) head bearings (type and/or torque) , rider & their riding style, and the roads, both the type, curvy or straight and their composition that affects whether it’s smooth or course, and of course the bike/rider weight. Our fjr’s seem to be pretty tough on the front tires probably due to the weight on the front and steering geometries,which also make head bearings/torque and tire pressures more sensitive.
My 14a that has a michelin pr4 on the front currently is just over 13,000 miles on it and I believe it will probably go 15k or more. It has almost no perceptible cupping/scalloping/whatever on it. If you clie your eye’s and run your hand over the tire you can feel slight variations but really not visible.
So why is my pr4 doing so well? Several things I believe have affected this, imho I believe that tapered tend to dampen any oscillation in the front tire due to what N4 describes above either in a turn or straight line, every bike that I’ve added tapered bearings to has had reduced cupping/scalloping/whatever. My 76 g-wing that I bought new developed head shake and tire cupping as bad or worse than the fjr. That was my 1st all’s-balls installation many years ago and currently only mildly cups the front by the end of it’s life. Of the 5 bikes that I currently can or do ride all have tapered head bearings and none really have bad cupping.
So I think a couple of other things affect my results, those being that where I live, to be able to get anywhere there’s a lot of either highway or just straight country roads, not a lot of technical stuff here. Also since I’ve aged a bit and several other life events the squirrel in me rarely ever comes out anymore these days. This is a fairly difficult thing to maintain due to the fact that I ride a red 14a, the very fastest color, ya know !
I also am religious about maintaining my tire pressures at 40-42psi both front & back, you do have a tire pressure monitor system right ? One of the very best farkles you’ll ever buy imho.
A final observation, have you ever had a rear tire scallop like the front ? I haven’t unless there’s something mechanically very wrong. Which points towards if the tire and it’s mounting are a stabile platform the tire doesn’t scallop/cup/whatever. This is what makes me tend to believe that the dampening that a good and proper set of tapered head bearings will reduce tire issues as well as tighten your bike up. My fjr was a big disappointment when I bought it new because it was a very loose & sloppy handling bike that required a lot of effort to corner. Input from our group here on tire pressures helped a bunch but it still felt loose, when the tapered bearings were installed my bike was transformed into the tight and precise handling bike I thought it should have been new. I’ll add that I do not believe that the oe ball head bearings were retorqued per Yamaha’srequirement at the 600mi service which I be;I eve contributed to the severe head shake at 6300miles. Anyway those are my thoughts.
Red 2014A, the fastest color !
Ride more,, worry less !