Yz400d rear tyre wear

[Big Scotty]

G'day
My problem is that the nylon chords in the sidewalls of the inside of the tyre are separating out of the rubber and cutting into the tube resulting in a puncture. This only happens on the sprocket side of the tire and only takes about 5 or 6 weekends riding to happen. Wheel bearings and swingarm bushes are tight,running Bridgestone 404 around 12 pound pressure.have had same rear tyre on my 380 for 2 years with no sign of this problem.has any one with the same model had similar problems.i have read the biggest problem with the d models was swingarm flex,could this be the problem?
Cheers scotty

[Paul552]

G'day
My problem is that the nylon chords in the sidewalls of the inside of the tyre are separating out of the rubber and cutting into the tube resulting in a puncture. This only happens on the sprocket side of the tire and only takes about 5 or 6 weekends riding to happen. Wheel bearings and swingarm bushes are tight,running Bridgestone 404 around 12 pound pressure.have had same rear tyre on my 380 for 2 years with no sign of this problem.has any one with the same model had similar problems.i have read the biggest problem with the d models was swingarm flex,could this be the problem?
Cheers scotty

Where  are you brother???
Canowindra is missing you

[Big Scotty]

I'm at home with a flat tyre LOL

[Paul552]

Them's  the brakes!!!!!

[David Lahey]

For what it's worth I've had a similar failure mode with competition trials tyres, but on both sides. I haven't worked out why some tyres do it and some don't. Maybe with your bike having a bit of power it could be swingarm flex, but with a 15 HP trials bike where you usually only use about 6 HP, it is probably something else causing it

[Ted]

Hi Scott,
             I've always run 404, 403 Bridgestones on all my bikes ranging from 125 to 500 and have never had a problem. However I run 15 psi and super heavy duty tubes on everything.

[Big Scotty]

Hey ted
I run the same tyre and pressure on my 125,never have a problem also on my ktm380,same tyre same pressure no problem,just on the 400 so I don't think it is a tyre issue,if its a frame flexing issue then somebody may have had similar issue with the same model
Cheers

[Ted]

Ask Hardman, he has a 400 D.

My 465 frame is gusseted to remove flex. Oversized engine mount brackets, oversized head stay mount, bigger diameter mounting bolts, gusseted frame and a welded skid plate.

Or alternatively you could paint the swingarm aluminium in colour. That will render it flex free and your tyre woes will be a thing of the past

[Sorelegs11]

A lot of the mx tyres that come in to my shop have the insides scrubbed out by heavy duty tubes, the tubes have the rubber from the inside of nthe tyre stuck all over them, front and rear,
Could be just one of those faulty tyres that turn up every now and then.
The only ones that I have seen with the cords causing pucture seem to have been run flat.