Ok, First this is long. Sorry. I've already threadjacked a couple of times, now it's time for my bike to have it's own thread, and maybe either I can get my bike set-up, or this will help someone down the road.
Background: Bought the bike used, set up for a 200-225lb rider per the description. I'm at 200, I'm guessing that the previous owner was 225.
The bike sits on its kickstand at twice the angle of any other bike in a parking lot of 50 bikes. This is due to ride height because I can not stand flat-footed on this baby, but can on virtually every other bike made, including 929's. (I should also mention that it has a Sargent seat, and that I've heard they are taller or more padded than stock, but that doesn't explain the kickstand)
This problem can be attributed to:
- Preload too stiff, the bike had zero difference between fully extended (rear wheel off the ground) and static unloaded. Also less than 2mm rear sag from just sitting, not pushing down after sitting on or bouncing.
- Pirelli Diablo tires, which I've heard are taller than most. I can not vouch for this one way or the other, this is my first set of Pirellis.
- Penske rear shock, I'm told, is longer than the factory unit. I cannot adjust it any shorter to get within factory height range, I've looked at it and it's as short as it will go.
So I've talked with the experts, IMO, about preload spacers, rear shock adjustment, etc. and have arrived at the conclusion that since I don't have a stock 954 to take measurements on, I should try to set up the sag properly. Using SportRider's L1,L2,L3 formula, and Dan Kyle's recommended "street" sag setting, I took another swing at it today.
These are the adjustments made, 03/25/06:
(measurements are from bottom of fork seal to top of lower fork end)
124mm fully extended (Pitbull triple tree stand), unloaded
93mm static w/rider after pulling the forks up and letting them settle
77mm static w/rider after pushing the forks down and letting them rise
equalling 85mm average
difference between fully extended and avg. loaded w/rider(street recommended sag is 36-38mm, but I decided to err slightly on the soft side)
(measurements from left lower part of pass. peg to spot on swingarm marked with electrical tape)
133mm fully extended
difference between fully extended and avg loaded w/rider (street recommended sag is 28mm)
It should be noted that before adjustments, the front forks had 122mm of fork exposed between bottom of fork seal and top of fork bottom, and at the end of the "tuning" there was only 113.5mm showing.
Well, the bike actually feels normal when sitting on it with my weight. It actually compresses a little bit. It's much softer now with 28mm instead of 2mm rear sag. I can lift the rear and actually watch the suspension move instead of just lifting the rear tire into the air without the swingarm pivoting. The front has much more movement when rocking the bike while holding the front brake. Still sits twice as high on the kickstand though.
5 mile test ride:
Bike felt ok, maybe a little soft when turning sharply side to side. One weird thing... I hit an 80mph sweeper and twisted the throttle. Next thing I know, I'm crossing the yellow line, running wide, totally unexpected for a curve that I've went faster than 90mph through. After 20k miles on 929's I can say that has never happened to me. Admittedly, I've only went that fast through that curve a few times, and I'm not overly familiar with all the dips in that road, so it's possible that I hit a dip and it pushed me wide, but I thought "proper suspension" was supposed to take care of that. What really bugs me about it is that it was totally unexpected and pretty much zapped my confidence until I got it back to the garage. I'm fairly worried about the next ride if on throttle is going to push me wide.
I have not tried stiffening the rear compression or softening the rear rebound per SR's recommendations to stop a wide running bike, but they also mention that if the bike is riding higher in the front than in the rear, that it will push.
I should note also that I called Traxxion Dynamics last week and they told me the baseline to start adjustments from (after sag) for their set-up was 1.5-2 turns out from full in on compression and rebound. I checked the bike, and they were set at that default.
I have not had a chance to bug Penske about their baseline set-up starting point.
In summary, I've ridden stock-suspended 929's that handled better and instilled more confidence for street riding. The settings are bad so far, but I'm going to attempt to get it better and do some more learning.
Thoughts and suggestions are welcome. I will post all tuning results from this point forward in this thread. Thanks for reading.