Well it’s been a week, and here is the FULL review of this tire.I just installed a new front tire It was reccomended by a Michelin rep, because the PA was unavailable.
Pirelli Sport Demon
130/70-18 mc 63H
Put it to the test today, feels real good. about the same as a PA but just a tad softer ride.
I had the dealer remove it and put a MPA BACK on....
This was bad.... REALLY bad....
I must admit that I was totally wrong about this tire.
First off my impressions, then my reasoning behind them
1) Tire Thickness
When my dealer was installing the tire I remarked to him then the Pirelli was wider, and thicker (tread depth) than the MPA. I had assumed that this would equate to a smoother ride.
Well it did however, however the increased width, had a big side effect, an increased contact patch, and with that SIGNIFICANTLY INCREASED STEERING EFFORT. This was really noticeable when just trying to move the handlebars in a parked or low speed turning situation.
(I will note that my ride DOES NOT have a rake, therefore there is more direct downward pressure on the contact patch, when compared to a raked bike. For example, try pressing straight down on the palm of your hand (at 90 degrees), and trying to rotate your palm, not too easy, now while keeping you palm on the table angle your arm to say 45 degrees. Now try to rotate your palm while applying pressure. A lot easier at a “raked” angle isn’t it??? This would explain my easier use when I tested the tire on my friends’ bike.
2) Rolling resistance and gas mileage:
Because of the increased contact patch there is now an increased rolling resistance. Which equates to slower acceleration (poor performance), and DECREASING gas mileage.
Acceleration:
I had first noticed that there was a loss of power about 60 seconds out of the dealers’ driveway. It seemed that I had to REALLY gun the engine to get up to speed on the busy route in front of the shop.
I attributed this (incorrectly) to the brakes rubbing as I had also installed new front brakes with the tire)
“The brakes will slowly retract” (I thought). As I later realized this was not the problem.
It is a common ratio of tire design… the wider the tire the higher the rolling resistance, the lower the acceleration, the lower the gas mileage (the tradeoff is straight line traction, which improves). I was feeling the effects of this compromise.
That loss of gas mileage was confirmed on my travel BACK to the dealer to remove the tire. The route I took (which I have taken before) usually took about 1 white mark on the gas gauge, NOW (with this tire) took about 2.5 marks (about 20%). Yes it was THAT drastic a change/loss in gas mileage, and the high speed turns, and acceleration was gain poor.
3) Hard Compound
When I first tried the tire it was on a country road with a few medium-speed twists (S curves). There were sweepers but at about 35 to 40 mph.
Executing these turns was “ok” except for the increased effort.
But then taking the same type sweeper turn at Highway speeds..... And the result was SKIPPING JUMPING and sideways sliding. Yes I said sliding. The front wheel would actually try and refuse to make a high speed turn. It wanted to track straight, skidding on DRY asphalt into the turn. I believe as a result of the REALLY hard compound of the tire. There was absolutely NOT road adhesion. This was not on some wet oil slick road; this was at high Noon (well about 1:30pm) at a temperature of about 64 degrees F. I did not experience this loss of traction. It is unknown if this loss of traction was due to the lack of rake, as I did not seem to have this problem with the raked trike of my friend.
After the replacement:
After the dealer changed the tire over to the MPA, the change of characteristics (read improvement) was IMMEDIATE. When I say immediate, I mean this. The bike was easier to roll off of the rack, and the simple act of backing up, and turning it by hand was 100% easier. Upon riding just in the parking lot, I found the ride was softer. The roll rate was notaiceably improved. I purposely rode the same rout I did when I came to the dealer, and did not put any gas in the tank. If the mileage had not increased then I most assuredly would have ran out of gas. I got all the way home on one marks worth of gas. The acceleration was back to its pre-Pirelli self.
Conclusions:
If you plan on buying this tire it is imperative that you a have a rake. However I’m really not sure if that will improve its characteristics. The ride once at high speed provided unacceptable handling, for the price of the tire.
The loss of performance, and apparent gas mileage was appalling and because of that also I cannot justify the purchase of the tire. Perhaps this was due to the fact that while acceptable, that this IS a rear tire.
The bottom line…
For my purposes… I’ll stick with the Michelin PA