I have just started replacing my nc21 forks however i got one apart replaced the seal and went to retighten the bottom bolt only to find it spins and doesnt tighten, i know that this is due to the damper rod design however i dont have a impact driver to tighten it and i have no special tools to push against it from the inside, can i use a hammer drill with the right hex fitment or does it have to be a impact driver?

I couldnt even strip the other fork as the bolt just kept spinning, its annoying as i dont realy want to take them to a shop and pay for this minor task!

I made a fork diver out of an exhaust reducer i had sitting around so that was simple, just wish i could also make somthing to do the bottom bolt up!

Try the hammer drill...what is the worst that can happen?

Other than that I can't think of another way without impact tools. I am in good with my Honda dealer here in Pisa to the point where I doubt they would charge me for something like this. They balance my tires for me for free after I mount them...

Cartridge hold tool.

get a yard brush and put it up the inside of the fork press down on the fork this will give u enough presser to tightion up the bolt and stop the internals spinning. trust me it works thar is demo on u tube using this method on a nc 30 hes one of are guys as well. under fork seal change on a nc 30. regards john