Could a bent spoke make your disc feel warped?

[Warthog]

My TA600 feels like the front disc is mildly warped, but when I took the disc off and offered it up to a flat surface, it looked perfectly straight. However, that pulsing in the lever under braking is unmistakeable.

However, I remember noticing that one spoke has a kink in it, right at the hub. Can't remember if it is in the bent spoke is at the same spot as the disc "kink" and may no longer be unless I rebolted the disc in exactly the same position...

Is it possible? I'd rather avoid buying a new disc!!

[paulc]

If the spoke is bent at all it would be the same as over tightening one spoke which will make a difference to the wheel balance.
Take the wheel to someone who can replace the offending spoke and check for any defects.
Dont mess with spoked wheels people dont realise spoked wheels should be checked yearly to avoid wheel colapse.
I learnt that the very hard way and will never have spoked wheels on anything I now ride.
Best wishes Paul

[Warthog]

If the spoke is bent at all it would be the same as over tightening one spoke which will make a difference to the wheel balance.
Take the wheel to someone who can replace the offending spoke and check for any defects.
Dont mess with spoked wheels people dont realise spoked wheels should be checked yearly to avoid wheel colapse.
I learnt that the very hard way and will never have spoked wheels on anything I now ride.
Best wishes Paul

Thanks for the input. I have already built my own wheel as well as trued others. It's not so much the affect on the rim I'm interested in.

I'd like to know if a bent spoke could result in mimicking a lightly warped front brake disc, or pull a straight disc slightly out of shape when bolted down.

My guess is not as this would mean warping the hub it is bolted to but best to check...

[pale rider]

If the spoke is bent at all it would be the same as over tightening one spoke which will make a difference to the wheel balance.
Take the wheel to someone who can replace the offending spoke and check for any defects.
Dont mess with spoked wheels people dont realise spoked wheels should be checked yearly to avoid wheel colapse.
I learnt that the very hard way and will never have spoked wheels on anything I now ride.
Best wishes Paul

that sounds worrying that mate what was the situation when it collapsed on you? hope you weren't badly hurt.....

[1gear1brake]

I would say that it's unlikely for a bent spoke to cause your problem as the hub is in the same location regardless of true or buckled rim. When you removed the disc, did you clean the areas on the hub where the disc fits? If there is any contamination between the disc and hub will make a true disc run wonkey. Try taking off the caliper and holding something like a screwdriver or allen key against the fork leg touching the disc. Give the wheel a spin and see if it reveals any gaps.

[BobA]

My TA600 feels like the front disc is mildly warped, but when I took the disc off and offered it up to a flat surface, it looked perfectly straight. However, that pulsing in the lever under braking is unmistakeable.

However, I remember noticing that one spoke has a kink in it, right at the hub. Can't remember if it is in the bent spoke is at the same spot as the disc "kink" and may no longer be unless I rebolted the disc in exactly the same position...

Is it possible? I'd rather avoid buying a new disc!!

Are you sure the pulsing is through the brake lever?

If there's any chance you're actually feeling it through the handlebars, check the headrace bearings don't need pinching up a tad.

If it is through the lever, check that the disk is sitting flush on the hub when you bolt it up, and there's no distortion or corrosion on the seating surfaces on the hub.

It's also worth checking your front wheel bearings, as a little play in these will mean the wheel, and obviously disk, can move side-to-side, and would cause similar pulses.

Finally, if you still think it's the disk, get the front wheel in the air, then use something like a screwdriver or a marker pen and a sheet of paper. Hold the paper against the disk, and then securely slide your screwdriver or marker pen upto it, but barely touching it. Slide the paper out, meaning the there's like half a millimetre between pen and disk, and spin the wheel. See if the pen/screwdriver touch the disk at any point as it spins, highlighting any runout. Hard to describe that, but I hope you get what I'm saying!


Bob

[paulc]

that sounds worrying that mate what was the situation when it collapsed on you? hope you weren't badly hurt.....

No I was lucky ,but the three cars comming the other way wher writen off,I just got a lightly sprayed(luck of the devil)

[paulc]

no i was lucky ,but the three cars comming the other way wher writen off,i just got a lightly sprayed(luck of the devil)

whoops (ankle)

[AlanH]

Dont mess with spoked wheels people dont realise spoked wheels should be checked yearly to avoid wheel colapse.
I learnt that the very hard way and will never have spoked wheels on anything I now ride

Rather than avoiding just about every trail bike out there, you could have something with spoked wheels but make a decision to maintain it. For a wheel to collapse it has to be in an absolute mess. It's not exactly a common occurrence under normal conditions.

So are you not concerned about cast wheel failure? They should also be inspected regularly for cracks.

[Warthog]

Are you sure the pulsing is through the brake lever?

If there's any chance you're actually feeling it through the handlebars, check the headrace bearings don't need pinching up a tad.

Deffo through the lever: more on harder braking, and I can hear the disc rub if I free spin the front when on the centre stand...