Do OEM tyres dual purpose tyres have a stiffer carcass than pure road radials?

[viewdvb]

I’m running on the OEM Bridgestone tyres. Problem is, I have never done any mileage on the original tyres before. I bought my last S10 at 3000 miles and immediately changed to road radials. Most of my subsequent mileage was done on Michelin Pilot Road 3s. I was fortunate to have the opportunity to compare the ride of my old S10 with my new 2013 model which now has 1000+ miles on it. Both had stock suspension and were adjusted to the same settings. The new bike is harsher in ride quality. I expected that the suspension would take a while to bed in but at over 1000 miles I would expect it to have settled to a norm by now.

My dilemma is whether to fit the Michelin PR3s that I have waiting on the shelf in the expectation of an improvement in the ride or to soldier on with the stock Bridgestones. I know the Michelins have more grip but I would like to get some value out of the OEM tyres if I can and I can live with their grip for at least one long haul trip.

My questions are:
1. Has anyone experienced the stock suspension becoming more compliant after the 1000 mile mark? Might I expect any further improvement?

2. Do the OEM tyres (or dual purpose tyres generally) have a stiffer carcass to deal with the stress of off-road riding compared with the carcass of pure road radials? If so, it might explain the difference in ride quality and induce me to fit the road tyres immediately..

Your comments would be valued and appreciated as always. Please note that I am not looking for recommendations on your favourite tyres nor comments on replacement/modified suspension – just the questions above please.

 

[markjenn]

These are interesting questions. My guess is that yes, to some degree, the 90-10 dual-sport tires (like the Battlewings) are a little stiffer than pure road tires like the PR3's. (I've never ridden PR3's, but I went through a lot of PR's and PR2's on my FJR and it always seemed like a very compliant tire to me. I mount my own tires and the Michelins always seemed easy to mount too, which is often a sign of a relatively complaint tire with more flexible sidewalls.) And as you're maybe aware, the Battlewings come in three versions for varying loads - one for the 475-lb bikes like the F800GS and Wee, another for 530-lb bikes like the R1200GS, and a heavyweight version for our S10's, Triumph Explorer, etc. The OEM fitment is the heavyweight version and I would expect it would be stiffer.

All suspension does tend to "loosen up" a bit, but I can't say I noticed it changing when I first owned the bike.

- Mark

 

[Rasher]

1. Yes, but only because I had the forks re-sprung and the shock replaced @1000 miles

2. Maybe....

But all tyres are different - as is suspension, same settings on different bikes can be quite different, I know R1's could have massive variances in the pressure in the shocks so one bike could feel very different to another, I also suspect the amount of oil could be a bit different, plus all other tolerances that could make two bikes supposedly the same in reality noticeably different.

I would just burn through the OE tyres unless I found them particularly horrible, mine had Tourance EXP's which I refer over Bridgestones which I never liked on my GS, was happy to run them through to extinction and then fitted Roadsmart 2's.

Not sure where I am going next, possibly more Roadsmarts (better the devil you know) or maybe PR4's.

 

[Checkswrecks]

Yes, DP tires give a stiffer ride. Google for "shipping weight" and whatever tire you are interested in. The PR3s are lighter than the DP tires of same size, so thinner more compliant sidewall and tread stiffness, PLUS surprisingly less unsprung weight.

 

[MojoToot]

I think my suspension continued "softening" up to it's present mileage of 4,000 mi.

But I also played with the settings during that time, so?

If I were you, I'd lighten the rear shock a bit & try that.

Tires definitely do (or can) affect the "cushiness" of the ride.

 

[snakebitten]

Technically, our suspensions "soften" from day 1 until they are either discarded or altered.

Cars, trucks, motorcycles........all do it.

Seals & bushings wear, fluids break down, springs deteriorate.....

 

[GrahamD]

Well if it's any help I went from the stock BW to the K60's and yes they were noticeably heavier just carrying the wheels back from the shop which then meant some damping adjustment to get them back to close to the ride quality of the originals. Never got there though. My recollection of swapping the PR2 that was on rear of the Strom when I bought to the AnakeeII was the same. So you probably have a weight difference which needs a bit more damping to be applied and a stiffer sidewall as well.

 

[viewdvb]

Yes, DP tires give a stiffer ride. Google for "shipping weight" and whatever tire you are interested in. The PR3s are lighter than the DP tires of same size, so thinner more compliant sidewall and tread stiffness, PLUS surprisingly less unsprung weight.

I never thought of comparing the weights of the tyres. Good thinking! It seems like a good indicator to me plus less unsprung weight can't hurt. Thanks to all for the insights.

 

[viewdvb]

Oops - there goes another theory! I actually weighed an OEM Bridgestone front versus a similar Michelin PR3 and there was less than an ounce difference. I did try a very unscientific test of applying a fixed weight to the top each unmounted tyre and the Michelin squashed radially twice as much as the Bridgestone. This seems to imply that the carcass of the Michelin is more flexible but we shall see. I've decided that, despite the OEM tyres having most of their life left, I'm going to fit the PR3s anyway to finally find out if there's any difference in the ride. I will post once more soon with the outcome.

 

[viewdvb]

Final post: I have covered a 1000 miles now on the Pilot Road 3 tyres and there is a definite improvement over the OEM in the comfort of ride. The road radials smooth out a lot of the smaller road irregularities as I had hoped thus reducing the perceived harshness of the ride with OEM tyres. The new bike now feels much the same as the previous one. That's without the clear improvement in wet weather grip and the additional dry tarmac grip at the edge of adhesion. I am pleased that I made the decision to install them before they were strictly needed.