I’ve wanted to learn to LDP (Long Distance Pump) since before I started skating. Every summer, I spend some time trying to learn to pump, and make minor adjustments to my setups to make it more practical, and for my efforts I could impart energy, but my setups have always been sufficiently sub-optimal that I only managed sustain speed with a pump a handful of times, and never accelerated.
This summer I decided do it right. I bought the classic inexpensive LDP truck set (A Bennett Vector and a Tracker RTS, I picked the 5.0 and 129mm variants respectively), modded them for LDP, and installed them on my suitably sized deck with suitable bushings and wheels.
Distance skating attracts the best sort of crazies – It’s something of an equipment sport, so they tend to obsessively purchase and modify gear. It’s remarkably physically demanding, so there is a lot of the classic solo endurance sport mentality. It also has carryover from the “raah hardcore” skate world. Fortunately, the internet has brought together the appropriate crazies at sites like Pavedwave and skatefurther, where the discipline has been developed from its roots in the 70s.
Designed-for-LDP decks (Subsonic Pulse, LBL Walkabout, RoeRacing Mermaid, etc.) are boutique items and tend to cost in excess of $150 for the bare deck, so I wanted to ease in financially in smaller steps since I’m not sure how capable I’ll be. Most sources say 26″ to 31″ is suitable for an LDP wheelbase, and my Pakala III is around 25.6, so it is manageable if a little tight-pumping.
The mods for the trucks are pretty interesting, I implemented a number of the suggestions from this excellent thread on the pavedwave forums.
On the Bennett, I made myself a nice Polyoxymethylene(aka Delrin/Acetal) insert for the pivot. I think the technical name for this thing would be a bushing, but since that term is already in use for trucks, people have taken to calling these “hobo sphericals” or “fixed spehericals,” as the more elaborate alternative is to install a spherical bushing. I saw that Griffin sells fixed spehricals for Bennett trucks that look to be machined out of some flavor of Polyoxymethylene, looked at the sheet of 1/8″ Aceteal I had for another project, and decided to DIY. For those looking closely at the numbers, the insert is a little thinner than ideal (0.125″ sheet, gap depth measures around 0.16″) but it seems sufficient.
I hacked a small chunk off the sheet, held it under the truck pivot, and scribed the diameter into the sheet with a pin. I then did the typical chords-and-90°-angles center of a circle stunt, sanity checked it against a washer, and drilled the center to 25/64″ in a couple steps (starter drill, some intermediate size grabbed at random, 3/8″ because I wasn’t sure how sloppy I was being, then 25/64″) — Kingpins are 3/8, and it should slide freely, so a V letter drill would probably be technically correct, but I’ve never contrived an excuse to own a letter drill set, and was free-handing it with pliers and a handheld drill anyway, so 25/64. I then followed my scribe line with a coarse sanding drum chucked into a rotary tool, and fitted/finished it with a finer sanding drum. I’ve checked on it a couple times as I fiddle with the configuration, and it seems to be holding up and doing its job.
If I ever get my Shapeoko into shape for this sort of thing I should be able to punch out some nice precision parts for this on it.
On the RTS, I clipped the wings a bit with a file, as apparently the wings will chew up the pivot cup if you don’t. I then polished out the file marks and the whole pivot pin on both trucks with some tripoli compound and a felt wheel chucked up in a rotary tool.
At the moment I have the Bennett wedged to +10°, with Green and Yellow tall Reflex barrels, and the RTS at -7° with some blue Khiro barrels I had around, both stacked on top of 3/4″ of risers to keep it from biting – gives a ~5″ ride height, which is not ideal.
I built up speed by pumping the first time I stepped on this thing (and then wheelbit, got some road rash on my elbow, installed some more risers, and accelerated again without the painful sudden deceleration). I’m still clumsy and slow pumping, and I’m sure the setup can be improved, but it feels wild, and the dedicated trucks make a world of difference.