It seems like every month or so, someone is writing into the 'Workbench’ section of the Wing World magazine and asking Stu for his advise on the front forks on our bikes. This comes up so often that I decided to give this subject it's own web page.
Unlike dirt bikes which are typically better protected, the fork tubes on GoldWings are fully exposed to the various road elements. As we make our travels, we don’t think much about this unless something goes wrong. This may be noticing oil rings around the tubes or worse yet, we notice oil dripping on the ground or traveling up our shirts as the fork seals have totally given out.
After performing various maintenance items on our bikes, I'm seeing a pattern where both the bushings & sliders are showing significant wear to the surface coatings and in some cases the coating is gone and now the parent material is being worn. As this condition continues, the fork tubes are no longer sliding nice and smooth but now are moving back and forth. A condition which is short of impossible to detect while riding.
Of key interest, is the fact that the wear is heavier to the underside of the bushing & sliders and noted more significant to the left fork than the right. In rebuilding the forks, the difference between 60K to 100K is very noticeable. This would include the oil turning to sludge and slivers of metal flowing out of the tubes when drained. It seems that Honda may have left out a critical maintenance item here as most of us aren't thinking about normal wear that is being introduced as we ride thousands of miles.
Another major observation is the vertical scratches to the tubes of varying lengths. These scratches range to those that can't be felt with a ball scribe, to others which have significant depth. Some of these were found to be leaking at the fork seal and others only being a matter of time. In thinking about these, there's 3 that stand out. 1) Oil isn't meant to last the "life" of the bike, 2) Road/Weather elements will take it's toll to the inner fork tube, 3) Fork Tubes do have wear items in them and require inspection & replacement.
Based on tear down inspection & findings, 60K miles appear to be the right time for fork rebuild.The images below were noted with mileage at 70K. Cost for total rebuild can easily double when the actual fork tubes require replacement. Some tubes can be polished where others can not.
Motorcycle Service & Repair