Conti Road Attack on 900 (again)

[bobh]

The front Conti Road Attack tyre on my 900 is suffering from an odd crazing effect. I've never come across anything like this before.

As you can hopefully see in the attached pic, the middle 2-3 cm of the tyre is not too bad, with only a few random scattered cracks (in addition to the inevitable small flint cuts). The area most affected is the 2 cm or so just either side of this. Then when you get further round the profile, to the area which is used when cornering, the surface is pretty much crack-free.

Because of the position of the cracked area, I’m inclined to think that it’s been caused by flexing rather than loading. If it were due to loading I’d expect it to appear in the middle of the tread (due to braking with the bike upright) and/or on the shoulders (due to cornering). This leads me in turn to wonder if the rubber is faulty, i.e. if it is insufficiently flexible or is suffering some sort of fatigue failure.

In the badly-affected area the cracks appear to be substantially longitudinal, and typically a few mm long. Again, this would support the flexing hypothesis. However, where the wording "RoadAttack" was embossed, they are more randomly oriented and some are larger (~1cm).

Some of you may remember that I posted a few months ago about not having much confidence in the front end in the wet on this tyre. So before you ask, it’s done just coming up to 4K miles, and with the exception of a few 10’s of miles when I tried dropping it to 34 p.s.i. to see if it felt any better, I’ve always run it at 36. It was fitted in mid-August last year, so has mostly seen low temperatures and a high proportion of wet use. The back tyre, incidentally, is holding up well and looks good for another 4K.

You may ask why I haven’t spotted it before. I can only say that you have to look quite closely to see it (in my case with reading glasses on), and it’s pretty much invisible when the tyre isn’t bone dry. Which is why I only came across it a few days ago when the sun finally came out, and I can’t say when it first made an appearance.

Any ideas? Have any of you seen anything similar? Is it dangerous? Is it a bum tyre? Should I refer it to Continental or the supplier, or both? Does the 900 have a reputation for overloading its front tyre? Could it be related to my riding style?

Bob

[cam7777]

I would get that looked at ASAP, looks dangerous to me.

I had road attacks on my 900 when I bought it and hated them, I have since fitted Bridgestone BT021's and it has transformed the bike.

Don't put yourself at risk!

Good luck

[taint]

Hi Bob,

not certain about this one, but isn't the Conti Road attack constructed from two different types of rubber? Usually the central band is a harder wearing rubber than the outer edges; which tend to be softer and stickier for cornering.

The cracking you're noticing would be roughly in the area where those two rubbers meet. The thoughts are that this could be caused by the ageing of the rubber, wear or stress possibly caused by the tyre being under or over inflated. The worst case scenario would be that the two rubbers are separating and it would be worth checking if Conti had issued any recall notices.

I hope this helps

T.

[teejayexc]

May 16, 2008 21:32:59 GMT @cam7777 said:

I would get that looked at ASAP, looks dangerous to me.

I had road attacks on my 900 when I bought it and hated them, I have since fitted Bridgestone BT021's and it has transformed the bike.

Don't put yourself at risk!

Good luck

As Clive says get it looked at soonest!

The D9 does tend to 'scallop' the front tyre, as yours appears to be doing on the extreme right of the piccy near the tread pattern, but the crazing/cracking is, imho, a fault in the tyre.

trev

[neilmud Lord Protector]

My D900 wore the tread blocks from front to rear I was told this was due to under inflation but I know they were blown up right it did it on bridgstones and Dunlops it could be felt at low speed as a rumble in the bars but not when running at speed may be what you have is the same thing showing differently on another brand of tyre. I was told it is because of soft and fairly long travel suspension on a D9

Neil

[bobh]

Thanks for the comments folks.

I considered going back to Bike Treads in Swindon who supplied and fitted it, but decided not to bother as I think the chances of getting much satisfaction from them would be fairly remote. So I’ve now contacted Conti direct via their website with a modified version of the above message (unfortunately no way of sending the photo, but I’ver told them it’s available). Basically I’ve asked them whether they think it’s dangerous to carry on riding on it, and if so what they propose to do about it, so the ball is now in their court. If they’ve got any sense they’ll tell me to take it into a local depot pronto to get it checked.

I’ll be taking the front end apart shortly to do the steering head, so the bike will be off the road anyway for a few days. I’ll keep you posted.

Bob

[cam7777]

Good man, sounds like your doing the right thing.

[DahDit]

It's not dangerous, it's normal for these tyres m8.

Sounds strange I know, but I think it's down to the different hi-silica compounds used in the Conti Road range. They're not dual compound tyres, hence they tend to be cheaper than the equivalent BT's

It's happened on all of mine that I've had fitted, and there's no ill effects. You may also find that the rubber is prone to marks, and minor cuts from stones etc.....but they are a sticky compound that'll collect such marks on imperfect roads. If you look at race tyres when they've been used hard, they have a less than perfect appearance to them too .

Keep riding it. The diamond shaped hole is from a sharp stone I guess. I'd say you've nothing to worry about.....from my experience anyway.

If it scares you, I guess the only option is to consider changing tyre - but as I say I've used Conti RA's for a while now (not had a puncture yet, touch wood). I love 'em because of their price and performance - I've had my pegs down in the wet using these "all round" tyres, they do the miles and the stick like glue in the dry.

I just check my tyre for stones, pick them out and generally check the roughening.

I thinks it's the ole' "They all do that sir...."

I'm sticking with them, but may try the 021's in the near future if the price is right. I'm not one of those individuals that won't try something new, I like to experiment - hence I came to the Conti RA's in the first place as previously all anyone wanted to use on the 900 was BT-020's.

I could never handle the 900 with as much confidence on the old 020's as I can on the RA's, which is one of the reasons I've stayed
with them.

[DahDit]

When I get a chance I'll post a pic of my front and rear tyre too to show you the same effect.

[teejayexc]

[I've had my pegs down in the wet using these "all round" tyres, they do the miles and the stick like glue in the dry.
/quote]

Not so good in the sand though

[DahDit]

Git.

I should mention that whilst Trev was visiting me yesterday to pick up some bigger cases for the Scotland Run, so he could fit Beebs' replacement pulling-shirts in as well as his & Diane's stuff, I got a text from my neighbour who works at Spurn Point.....

Saying he'd just dropped his bike on the sand also......and he commutes there! Apparently the sand wasn't there last week......that was his excuse. I didn't have one. Fortunately, all he broke was an indicator on his SV650.

Hence Spurn Point is off the Yorkshire Run.

[teejayexc]

May 17, 2008 19:13:45 GMT DahDit said:

Git.

I should mention that whilst Trev was visiting me yesterday to pick up some bigger cases for the Scotland Run, so he could fit Beebs' replacement pulling-shirts in as well as his & Diane's stuff, I got a text from my neighbour who works at Spurn Point.....

Saying he'd just dropped his bike on the sand also......and he commutes there! Apparently the sand wasn't there last week......that was his excuse. I didn't have one. Fortunately, all he broke was an indicator on his SV650.

Hence Spurn Point is off the Yorkshire Run.

;D

[CD]

My mate hit a car that wasn't there la

I recently put a pair of Conti RAs on my 900. They are certainly faster steering than the Conti Force pair I used previously and the RAs inspire more cornering confidence. The downside is a slight steering wiggle at about 40mph which I suspect is a combination of suspension wear and the less stable tyres. Its also less stable above 80 when heavily loaded with luggage. But of course in the UK that's not an issue.

So for quick handling on a lightly loaded bike the RAs are tops. For high speed with lots of luggage, the Conti Force is probably better. As ever, trading fast steering against stability.

By the way, the Conti Force front tyre became badly stepped and though it was still legal I decided to replace when the rear was worn out. The stepped tread looked dodgy, but it never caused any nasty events in the wet or the dry.