Check setup before suspension upgrades

[tater]

Hi folks, first post. I love the forum. It's an invaluable asset for FZ-07 owners!

Since I've owned this bike for 7,000 miles now after a long hiatus and return to motorcycling, I trusted the reviews I read everywhere that this bike's suspension can't or doesn't work well in stock form. Disclaimer: I am within a few pounds of the stock springs ideal weight (170lbs naked), so that DOES make a difference.

I'm on the second set of tires. The first were BT0023. The set I'm on now is Dunlop Sport Max III. I planned to go with PR3's or 4's, but my dealer said they were similar, but 30-40% less with rebate so I went that route. These Dunlop's are HARD. That's okay since I wanted the long wear so I could redevelop my skill, but it made the ride immediately worse, more harsh than the stock Bridgestones that came on it. They don't look "new" with 6,000 miles on them, but another 4,000 shouldn't be a problem.

I don't have any tire to advocate, but I can tell you that at my weight with these tires and just the stock rear preload (position 3) and reduced tire pressure feels like butter compared to 36R/38R that's "recommended." I put this in quotes because it's most likely a legal requirement to err on the higher side(?); higher pressures supports more weight, such as a passenger or load. My tire pressures are below...

Too low (or high) tire pressure is BAD, but what is appropriate? I've given my weight and the tire, so don't assume my setup will work for you. Everyone's needs are unique. My style is casual to slightly "spirited" and I feel I have intermediate or just above average technique: e.g. body position, pretty smooth on throttle & brakes, and keep the suspension loaded/unloaded as necessary for cornering (stability, contact with road); IE, few "jerky" movements or input.

I initially chose to start dropping pressure because the rear was: 1. stepping out on acceleration & braking, 2. clearly wearing a flat spot on the center of the tire. These ARE multi-compound tires, more silica in the middle, so that should help, but these 2-3 factors were telling me I needed to do something different.

For about 1,000 miles, I rode at 31F/33R. The front end felt less like it was skipping over marbles at speed, 50mph+, although still not to my satisfaction. Well, I went with 28F/30R a few days ago and it feels like what I would expect with $1,000+ of fork and shock upgrades. I base this on experience driving and "amateur tuning" sports cars. I have neither raced bikes or cars professionally. I aim for SMOOTH, balanced feeling for 90% of my riding style. The bike feels great at low and moderate speeds; I have not tested high speeds, or plan to ride regularly above 80mph.

TEMPERATURES! Almost forgot. I've been riding mostly in 80-85F with full or medium sun (warm to hot pavement). I don't know how much you might want to adjust, or if any adjustment due to temperature is necessary (it is, somewhat), but this is something I plan to test for as well. Tire temps: **I have not noticed extreme heat or wear with the lower pressures. That doesn't mean it won't happen! E.g., it COULD with a heavier rider and probably WOULD on a race track. Will continue to monitor.**

So to recap: buttery and responsive feeling with: 170lb rider, 3 rear preload, sport max 3, 28F/30R pressure. I no longer anticipate doing fork or shock work or shopping for a replacement motorcycle due to ride quality because I've found something that works for me. Yay!

 

[Correction for this paragraph: Front still dives quite a bit. Might look into the Race Tech GVE's. Don't think I'd like a stiffer spring.] The severe front end diving on braking seems to be **improved** from the changes: dropped 3lbs in front and rear, rear preload from 2nd softest to stock 3 setting. I don't really know how this happened, unless the stiffer rear reduced mine and the bike's weight shift by the shock & rear spring staying more "loaded" all the time. The difference in preload was only 1/4-3/8" higher with setting 3, I think. My "proper sag" is 2 if I remember. 35mm? At 3 it's around 28mm.

Edited July 18, 2019 by tater

[Beemer]

Welcome and congrats! 

[mjh937]

Interesting write-up.  Thanks.  My 2015 manual says 33F/36R.  They must have increased it for the MT models for some reason.  I will have to try a couple of psi less and see what I think. 

[Zephyr]

Welcome and glad you found a combination that works well for you. 

It's interesting that you dropped psi to get the feel that you were looking for (perhaps due to new tires).  I'm a bit heavier than you and for the BT023's that are stock on my bike I went up from the manual's 33F/36R a few psi to get the crisp feel I was looking for.  It feels mushy and un-defined when the psi is per manual for me.  The difference for me is enough that I can always tell when I need to add a few psi by feel alone when riding.

[elmo]

Tator welcome,

I agree, is best to understand the stock suspension setup before making any suspension changes. Typically this is done by understanding the bike and rider sag numbers vs. using tire pressure for adjustment. I ride mostly track and run Q4  at 28 rear and 30 front, while this allows the tires to heat up for great traction, lifespan is short. Using zip ties is an easy way to learn how the front forks are performing.  Plenty of videos on the topic.  https://www.youtube.com/watch?v=mK3flKxf41U