Tweaking a new setup

beaker · Tweaking a new setup

Hi all, I'm based in Cambridge, UK and am new to pumping. I've just recently put this setup together with lots of help from posts on this forum and the Gear pages (THANKS!!):
Fibreflex 44 Kicktail, trucks mounted on shortest wheelbase options
Front: Bennett 5.0, 15* wedging, orange/white/blue cone khiros
Rear: RTS 129, 10* de-wedging, red/blue khiros

I don't have any long trails near me but have a nice smooth 3.4mile (1.7miles each way) run that's mostly flat with a few very gentle inclines. I've been out on this a couple of times and the pumping is going well: I did the 1.7miles back without putting a foot down yesterday. I think I averaged about 10mph which I was pretty pleased with given the uphill bits on the run.

I'm wondering about what I could do to tweak the setup to maximise speed (lack of a long trail suggests I try and work the route I ride to be a bit more of sprint) so hope someone can help...

1. Wheelbase - does longer wheelbase translate to higher sustainable speed?

2. Does more wedging up front mean higher sustainable speed or just easier initial acceleration?

3. Does more dewedging in rear mean higher sustainable speed?

4. I initially set my board up with 22* wedging in front but one of the heads of the trusshead khiro bolts I had (right hand inner) just kept popping off just testing the setup outside my house! (despite following all the advice to not turn the head, turn the nut). Unfortunatlely this meant I haven't been able to try steeper wedging on a long run. Any other tips for avoiding this?
(Note that as per the advice that comes with the Khiro wedging kit, I drilled out the front truck mount holes in the deck at a slight angle to accomodate the bolts with the >15* angle risers - that was the only way I could actually get the truck on with 22* of wedge!)

Thanks for your help!

-Paul

LDPanda

1 Yes, in general a longer wheelbase provides a higher top speed but it will make it a little trickier to pump at low speed. Once you feel pretty comfortable with the basics of pumping i think its a good idea to pull the wheelbase out as far as you can and try it, you can always go back to a shorter wheelbase.

2. More wedging up front translates to quicker initial acceleration and easier pumping at low speeds. For top end speed you probably want less wedging up front, more like 10 or 7 degrees. Less wedging will give you more stability at high speeds but make pumping more difficult at slower speeds.

3. Hmmm, to a point, i suppose. First off, you already have the RTS dewedged 10* which is pretty good. You certainly dont want to bring the kingpin past perpendicular with the deck, that would reverse the turning of your truck. I find the 'sweet spot' with an RTS is to have the KP 2-3 degrees wedged of perpendicular (if that makes any sense). But yes, a less turny rear gives you better top end speed. You dont mention your weight but blue khiros seem a bit soft for the rear, might change to double reds or reds/yellows for better top end speed.

4. Busting the heads off bolts is a common problem. If youve tried washers and youve redrilled the holes I dont know that theres much else you can do. Try not tightening them down so hard and ride it (in a controlled area) then tighten them down slowly as you ride some. The pressure and vibration from riding will (hopefully) bend the bolts properly and youll be able to tighten as you go safely.

cappa · bolt heads

Barry posted some pics of his LBL Walkabout a while back, which showed his solution to bending the bolts. Pretty cool I think. It should solve the problem with the bolt heads.

I hope he doesn't mind if I repost the link the photo.

http://picasaweb.google.co.uk/Kno...about10092008#5244422021695673490

beaker

Thanks for the info - good advice. Will definitely try the red/yellow bushing combo in the back. Sounds like 15* wedge isn't too much of a problem - maybe I'd need to go for more if I was doing more hill-climby stuff?

I like the wedged washer idea. The problem I had when trying the 22* wedging was actually just getting the bolts through the holes in the trucks at that kind of angle with the bolts perpendicular to the deck was pretty much impossible - do people drill the holes in their trucks out a bit so the bolt will go through when the baseplate holes is at such an angle to it?

Cheers, Paul

cappa · octane virage risers

The Octane/Virage machined risers with the elongated hole may be solution.

http://octanesport.co.uk/virage.html

jeppak

hey,

my son is also riding the same setup. Because he is still a light weight, he has soft bushings in the rear truck (orange khiros). But because of that I noticed, that the tracker (rts) turns still a lot, also with 11° dewedging. So we tried a little more, I believe its now something like 15°. It works better. My own reartruck, the virage, is not turning at all, just neutral.
Maybe it works also different with harder bushings and more weight.

Greetings, Philipp

Ian the Groove Worshipper

Welcome to the forum, Beaker Smile

It sounds like you are off to a great start.

If you really want to get your setup dialed for speed, timekeeping is essential. Otherwise, you'll be relying on your subjective impressions of how fast you are going which can be misleading. The clock doesn't lie. A GPS can be a good tool, as well.

Set up a section of your trail and time yourself. I'd recommend starting off by playing with your rear bushings. Spend one session swapping out rear bushings, and doing timed runs. See what works best for you. See what feels best for you. Maybe the fastest setup won't be the most pleasing to you. Personally, I find that a looser back truck is more effortless and surfey, while tighter has more top end.

Spend another session playing with front wedging. Do a timed run at 22 degrees. Then try 15 degrees. Then try 10 degrees. Then try 5 degrees. See which one you like best. See which one is fastest. It may not be one and the same. But at least you'll know.

I believe every board has a sweet spot that will work just right for you, which comes with the perfect combination of bushings and wedging. To find this, a wedging kit, bushing kit, and an cordless drill with a 3/8 deep well socket attachment are invaluable tools. Just keep experimenting until you find what works for you. The key is to try to spend some time with each setup change to allow yourself to adjust to it prior to discarding it as being ineffective. Some setups are "an acquired taste" that you may not click with at first pump - kind of like good music.

Your wheelbase will most likely be determined by how flexy you like the board. Longest would be preferable for high speeds, but if it makes the board too soft, you'll be better off going with the shorter one.

If you take this approach, you'll deepen your understanding of how your setup parameters affect feel and pump efficacy. Learning by experience is always better than relying upon what others tell you. You have a great starting point given the revered Gear Page recommendations. It has got you a very nice setup, and you're off to a great start. Now you can have fun with setup experimentation. Make sure you share with us what you learn.

beaker

Thanks for the advice - I would like to experiment more if I ever get the time.

A problem I seem to be encountering over here in the UK is getting hold of long bolts. I really need some 2.5" bolts but can't for the life of me find any of the Khiro 10/32 truss head or pan head ones (apollo11shop.co.uk says they have them but they're not in stock).

Is there a metric equivalent (size, head shape and strength) to the standard 10/32 UNF (I think) bolt size that anyone has any experience with?

Cheers, Paul

model.citizen

closest metric size is 5mm, which isn't *that* common in long long lengths.

beaker

I've found some M5 x 60mm (2.4 inch) on ebay so may give them a try if I snap any more Khiro bolts.

BTW, I'm using 71mm 79a orange Bennett Alligators on my board and they seem pretty nice. Early days, but they seem to grip pretty well and roll nicely on the smooth trail I'm mostly riding. They're not so great on rough roads but no surprise there really.

-Paul

beaker

Got hold of the M5 x 60 bolts today and have now mounted my front Bennett at 19* (15* + 4* khiro hard wedge + 2 flat thin shock pads). I put large "'penny" flat washers on the under the bolt heads on the 60mm bolts to spread the load. I've only tried it on my patio so far but have jumped up and down on it, twisted side to side a lot and no heads sheared off yet - true test will be a decent length run. I wonder if there is a bit of a manufacturing defect with the 3" Khiro bolts I was using - when the head popped off it looked like it was just spot welded on....

One strange side effect of using the large flat washers is that the board rattles when I'm pumping - I think what is happening is that the shock pads are compressing slightly as I lean to one side and releasing tension on the bolt. As the bolt is held in place pretty tightly at the truck end as it goes through the truck mount hole, the only place it can move is at the bolt head end above the deck. This causes the washer to be temporarily loose and so rattle. I don't think this is a problem (time will tell) but is an interesting sound effect as I'm pumping along.....

Cheers, Paul

model.citizen

i got the same rattles after i added flat washers to the top of my setup.

rode it for a day, then snugged up the nuts a little more...no rattles now.

a spot of contact glue underneath each washer will also prevent rattles.

Ian the Groove Worshipper

Just an idea-
3/8" washers are too large
standard tolerance is too loose
something more snug may rattle less
try a 1/4" washer

Tweaking a new setup

bolt heads

octane virage risers