DARK SIDE FRONT.

[barbagris]

No - not a Car Tyre - but M/C rear tyre mounted in reverse on front rim.

I am using an 140/80 Avon Azaro - but that has stopped production.

What are other front Darkies using? - If you post photos showing the curvature it would be appreciated.

Having trouble finding tyre to rim fitting tables - only Avon seems to publish them. But Avon here is getting a bad reputation in terms of availability and delivery. 3 weeks seems to be the norm.

Z (W) rated preferred. But if it has to be V - so be it.

Yesterday did 275 kms. All highway (but we have bends in ours) - Average 130kph and at 37ºC. Visible tyre wear - tread depth on the edges reduced by 1/2mm. So the Azaro is not going to last much longer. Since fitting a EMAX on the rear there is also a notable weight shift to the front tyre. Can feel the forks struggling more - waiting for the Maxtons.

 

[Dean0]

Mate of mine runs a Bridgestone Battlax BTO23 160/70ZR17... reckons it works for him.

 

[PacificRimSurveyor]

I chose the the AVON Trailrider it is a 90/10 street/trail tire Dual compound. 160-60-17 after reading rim sizing tables I determined that was the widest I could fit under stock fender.

I really like the aggressive look of the tread and it feels glued to the pavement.

I also run Dark on the back:
BFG Sport Comp 2. 225-55-16

I do not regret either choice and would do it again.

I've run Car tires since 2006 after 3-Metz on my first R3.

 

[Joesmoe]

I'm wondering, what is the issue, if there is one, with running a "rear" tire up front. I've sometimes thought, "Great ! I found a tire that would fit. Darn ! It's a rear tire."

 

[DEcosse]

I'm wondering, what is the issue, if there is one, with running a "rear" tire up front. ..

Some good FAQs here from an actual tire manufacturer on the important aspects of construction and tread grooves direction
FAQs | Avon Tyres

Can I fit a front tyre on the rear and a rear on the front?
Avon would not normally recommend this fitment. If you do this however, due to the way tyres are manufactured, you should reverse the tyre’s direction of rotation if you fit a front tyre on the rear or a rear tyre on the front of your bike. During tyre manufacture, a length of tread rubber is wrapped around the carcass and joined together with an angled bevel type joint. This joint is orientated so that as the tyre rotates, this joint stays shut. As the rear tyre provides drive and the front tyre provides braking, the joint is made one way for the rear tyre and the opposite way for the front. Fitting incorrect tyres could cause potential MOT/insurance issues and may affect the bikes handling capabilities.

Why does the front tyre appear to be running the wrong way?
We call this Inverted Front Grooves. We have done a great deal of testing and research on tread patterns and found the front tyre is better run in the opposite direction to the rear. The front tyre has to deal with braking forces and the rear wheel with drive forces, which are basically opposite forces. This may make the front appear to be running the wrong way round but in wet tests, we have found that the footprint is not long enough for water to channel very far through the grooves, it just needs to be expelled sideways quickly. By running the tyre as we do, we significantly reduce irregular tread wear. This means that even when the tyre is half worn, it is still putting down the correct amount of rubber on the road. Tyres run the other way round suffer from stepped and irregular wear which reduces their footprint and effectiveness in the wet quite dramatically.
If you check out any of the latest sports radial tyres from any of the other main tyre manufacturers, you will see they are all starting to do the same.
See IFG, (Inverted front grooves) section Tyre Technical Symbols | Avon Tyres

 

[Ygransom]

I'm wondering, what is the issue, if there is one, with running a "rear" tire up front. I've sometimes thought, "Great ! I found a tire that would fit. Darn ! It's a rear tire."

Just mount it so the rotational direction arrow is backwards. Rear tires are constructed to resist the forces generated during hard acceleration - front tires to resist braking forces. I have run rear tires on front of multiple bikes over the last 40 years with no problems.

 

[barbagris]

I'm wondering, what is the issue, if there is one, with running a "rear" tire up front. I've sometimes thought, "Great ! I found a tire that would fit. Darn ! It's a rear tire."

The biggest issue is RIM suitability. The front rim is only 3.5" wide. When I initially looked the Azaro was the ONLY Z rated rear tyre specc´d for a 3.5 rim. Itś lasted twice s long as either a Me880 or Avon Cobra front. The plus - more tread.

I am surprised about 160ś being used with such low profiles - as they must be a pinch fit to the rim - but the info is much appreciated. Equally surprised they dont rub the mudguard.

A BT023 would do me. And if a 160/70 (or 160/60) works so will the 150/70. Or dare I say it a 140/70. ime Narrow front = better steering.

AVON also may be that last tyre mfr that makes UNIVERSAL front&rear fitment tyres. But not in R3 sizes.

 

[PacificRimSurveyor]

Yeah, I forgot to add some information.
Do your research. (See Decosse above)
I read all the info. available.

Basically the reasons to reverse mount a MC Rear tire on the front is : the way it's manufactured to to handle the acceleration load by reversing you allow the braking forces to disburse the same way. With the strength of the manufacturing design.

Also by reversing you allow the tread pattern to disburse the water on the road.

If you check your standard MC tires you will see the pattern directions match when reversing a rear MC on the front.

 

[barbagris]

If you check your standard MC tires you will see the pattern directions match when reversing a rear MC on the front.

On Bikes this is true - but "just for fun" take a look at some scooter tyres - they'll more often than not have identical grove patterns front/rear - no reversal on front. And it's not poor fitting.

 

[barbagris]

Opted for a Bridgestone BT021 150/70R17 (69W)

On paper the rolling radius equates to a 140/75 and 4.5% less than the 150/80 OEM



imo it´s a light "pinch fit" but nowhere near as pinched as the OEM 150/80 Metzler front. Will fit tomorrow.