[NQ1090]

My front rim at less than 10,000kms has become slightly buckled to the point of harshness/mild-shaking through the bars at 100kph on bitumen with a new Motoz Tractionator GPS tyre fitted. A mate has 4,000kms on his still running knobbies & has the same problem but it's also not the tyre. Initially I thought the Tractionator had some nasty "high spots" to wear off, but it didn't improve although it is worse at the start of a ride than at the end. I ride 70-30 bitumen road to dirt road at up to 120-130kph on the dirt, running recommended pressures & the tyre is not damaged. Yes I can hit holes, wash-outs etc, but a previous cast wheeled Vstrom did the same terrain at similar speeds without an issue. I assume the same Akront rims are used world wide. Not sure if this would be classified as a warranty issue due to the bike being used "off road", but did not expect this on a AUD$20,000 bike built for these conditions. Anyone else experienced this?

 

[mad_mardigen]

So if I understand you correctly you start to get a shaking vibration at 100kph? Could it be that the wheel has become unbalanced? or can you see actual damage to the wheel?
Could be that you lost a wheel weight and the wheel needs to be re-balanced.

 

[NQ1090]

On the centre stand & lifting the front under the bash plate, I rotate the wheel & there is visually lateral runout in the rim but no defined flat spot like from running over something immovable. The runout would be approximately 6mm in one area of about 150mm long around the circumference (if that makes sense) which I now see happens to coincide with the position of 2 large spoke-clamped wheel weights. Old tyre which was a K60 Scout had one smaller weight to balance it. Is it possible to tweak a rim while fitting a tyre? Could it be a bike shop warranty & not a factory warranty?

 

[jam20ster]

The difference is you are now on a spoked wheel vs a cast wheel. Spoke wheels need to be trued often just as any dirt bike wheel does. There is nothing wrong with either of your rims. This is normal maintenance.

 

[jam20ster]

Also not only do spoke wheels need to be trued (side runout) but also balanced (since you are riding at higher speeds). Once again all this is normal maintenance. You can buy a decent truing stand for $75 usd.

 

[NQ1090]

Um, no there is something wrong with the front rim. The chalk marks are from rotating the wheel in a vice & checking runout. The visible marks are obviously high spots, which means no chalk is low. The single large "stripe" is the only one on that side (r/h on the bike) & there is no chalk on the opposing side which means, it's buckled. I'll put my hand up for the small ones, but not necessarily the large one. If they can get all of that out adjusting the spokes I'll owe them many beers.

 

[jam20ster]

When you say vice, is this a truing stand? I know people use homemade truing stands and although helpful, can sometimes give false readings due to the inability to keep wheel perfectly straight.
Also when you say buckled are you referring to both side outward at the same point of rim? Reason I am asking is looking at your pictures it shows chalk runout at the same point of the rim on both sides. I'm trying to understand your dilemma.

 

[NQ1090]

The axle was through the hub, & a shaft of the same I.D. as the inside of the axle was secured to the vice with the wheel vertical as it mounts to the bike. The wheel was perfectly straight while being rotated. We are not measuring for .001" runout which will have no affect on tyre runout, but for millimetres of runout or buckling if you wish which we do have. The photos are misleading in respect to position on the rim of the runout markings on both sides & only done for clarity of the chalk marks. So the larger runout section is not opposite any other runout markings regardless of the what it looks like in the photos. The wheel is at the dealer, is the second one they have as a potential warranty from being bent, & there are 2 rims in stock at KTM Australia. I am a qualified car motor mechanic of 40years experience with my own business & more accurate measuring equipment than most mechanics due to my performance engine building, so I have a fairly good idea if something is bent, so my "dilemma" is that.... the wheel is bent....without doubt.

 

[NQ1090]

Update - just received the wheel back with new rim replaced under warranty. The bike shop tried truing it with spoke adjustment first & it only got worse. They were not able to find an Excel rim 2.5" wide either, only 2.15" which would not be ideal & it would no longer be tubeless. So, all fixed.