150/70 touring-tyre or 150/60 sport-tyre for B400

[Squishy]

Hi.

I don't need new tyres yet, but was interested anyway.
I currently have dunlop roadsmart 110/70  150/70. I'm pretty happy with them and wouldn't say I need other tyres.
However I'm very eager to try out sport tyres on my b400. I like sportive riding so extra grip wouldn't hurt.

The sport tyres are only available in 150/60 (don't want 160/60). I know this will change the 'gearing' to even more RPM so i'll probably change the front sprocket to 15. Also the 150/60 will lower my 400 by 15mm. That kinda sucks. I do have other dogbones so it's 30mm higher on the rear compared to stock.

Anyway, some people tell me sport tyres won't get warm enough (or quickly enough). Is this true? I'm talking about tyres like the pilot power or even the new bridgestone S20.

How would you say a tyre like the S20 would work on a b400? Or should I stick with 150/70 and roadsmarts 1/2 / road 2/3?

Thanks :)

[interfuse]

I run pilot powers and love them.  No issues warming up and on the b4 you get good tire life out of them.

[Squishy]

I run pilot powers and love them.  No issues warming up and on the b4 you get good tire life out of them.

What about ride height?

[interfuse]

I went from sport touring tires that were 70s to sport tires that were 60s. I didn't notice the 10mm difference in hieght but I did notice the amazing stickiness. 

[Squishy]

I went from sport touring tires that were 70s to sport tires that were 60s. I didn't notice the 10mm difference in hieght but I did notice the amazing stickiness. 

Well actually its 15mm (90mm vs 105mm) I think it's quite significant??

[interfuse]

Then stick to the 70s. 

[Squishy]

Then stick to the 70s.  

Hehe. I was just saying 15mm should be noticeable. Especially since ground clearance isn't one of b400s strong points