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My Darkside Experiment

4.6K views 13 replies 7 participants last post by  JoelTheMole  
The tire was initially inflated to 26 psi, but after riding two blocks, I increased it to 38 psi, which improved the ride greatly.

At any highway speed and going around fast smooth curves, I felt no difference in handling. At 40 psi, It was smooth and steady up through illegal speeds.

However, performance on rough roads and at slow speeds is very different.

There are several Youtube videos of guys showing that these tires don't affect slow-speed handling to do MSF parking lot drills. While this is accurate on smooth parking lot pavement, this doesn't show the effect of this tire at slow speeds on irregular road surface. The flat profile becomes like riding with an overweight, uncooperative passenger on the back, throwing their weight around in unexpected ways.

Most road irregularities run parallel with the road, ie like small ruts in the road. The flat tire profile finds and fights with any ruts or ridges, forcing you to constantly correct with the front wheel, just like riding a light weight dirt bike on fire roads. It's difficult if not impossible to find and set up smooth lines through curves with having to constantly correct. And the tire wants to drift off the crown of the road even when smooth.

Worse, at walking speeds over irregular surfaces, the rear profile can suddenly and violently pitch the bike. If not holding on tight while maintaining balance and footing, you could easily drop the bike.

There is one Youtube Goldwing guy that drilled two holes through the sidewall of his rear darkside tire, and then rode another 20 miles at speed without trouble. This is a real benefit.

Ironically, I found a Bridgestone Excedra for $177, so the cost savings at replacement time might be nil. Any real cost savings might only come with less frequent replacements.

In summary, I see the attraction to using a tire like this on a Goldwing, which spends long hours straight up on flat interstate roads and highways. I like the outrageous look, and will keep it mounted for a while, but for casual around-town cruising, the tradeoffs aren't worth it to me.
There are a couple things to consider:

You are using a tire designed to be run at around 30-35psi on a car that weighs more on each tire than your entire bike, and you are running it at 40psi... You handle more like a motorcycle tire because it is ballooning out the tire from over inflation, but you are loosing all compliance by pumping it up rock hard and losing the traction benefits you will see at something more like 28-32psi, especially on rough roads, gravel, and crap on the roads, this is probably making your problems with irregular roads worse.

You are doing a rough combo with a wide rear tire and very slim sidewall, switching to a 195 or 205 on a 16" rear wheel/tire combo with a much taller sidewall would make several improvements.

Give it about 500 miles before you make your final choice, both for you and to allow the tire to break in and loosen up a bit. Right now you are feeling all the things that have changed for the worse, or just different, but you dont have enough experience yet to understand all the upsides. Also, keep in mind your issues you listed so far are not performance ones, they are low speed wandering issues and once you get used to them it is just another one of those things with riding a bike you become zen about, at least I know I did. Motorcycles are self correcting in many ways, as I like to say I control my car, but I direct my motorcycle, and this is why: