Fork Shudder only at speed

[Del]

Hello All - I am in need of assistance from you good and wise people.

I have a K2 and am getting a shudder from the forks (can see them vibrating) when I get over 80mph and not able to drive through it - it actually gets worse - it starts as a slight vibration and gradually gets quite bad

Now I have so far changed the following
Front wheel bearings
Head stock bearings
checked tyre for buckles and bulges
checked calipers and brake pads
tyre pressures

Yesterday I noticed that the right hand fork seal (the one that I think is vibrating more) popped the seal - so I stripped the forks to change oil (did seals at same time) and check levels and go over the fork internals - the forks are now set exactly the same but today the same issue is still there

the discs are true as no pulsing under braking (at speed and general riding speeds) 

its driving me mental and ruining what is a tremendous bike

Del

[Rufus]

Mad idea, but could it be the rear wheel balance or bearing?
I have a similar issue and have done the same front end checks, so the only thing left that I can think of, is that it's caused by the back end, investigating this weekend..

[seth]

how many miles as your bike done?
could be worn bushes inside the forks if high milage
worth a check if your doing fork seals anyway.
also as already said check both wheel for balancing as that can affect things.

good luck

[gsxbarmy]

Del - I'd look at wheel balance, but would also suggest checking your discs are running true (not warped slightly) and that the bobbins are free.

Strangely though it could also be the front tyre. I had a similar issue on another bike I had years ago, and like you it drove me mad, in the end I changed the front tyre and all was well again. Don't know why, the tyre looked ok, the only thing the fitter could think of was that I had gone down a large pothole at some time and it had damaged the tyre wall in one place.

[Del]

Cheers for the help so far gents - I forgot to mention I checked the front discs with a dial gauge and they were running true - I am not sure of the state of the bobbins so imagine there not at there best
Im in for MOT tomorrow morning so will see about a new front tyre as I was kind off leaning toward the tyre . . . . . .mainly as it was the only thing Ive not changed so far

Thanks chaps 

[seth]

worn tyre could be part of the problem. hope you get it sorted .

[gsxbarmy]

Keep us posted Del - good luck with the MOT tomorrow

[Del]

sorry @seth forgot about you mate - the mileage on the bike needed converting - it was 31000 last year before I changed the clocks but my bike was weird it showed speed in MPH but odometer recorded in KPH so was 31196 Km which equated to 19384 miles - so add this year and it looking about 20K on the bike

[seth]

no worries buddy its not done mega miles so fork bushes should  ok
a strange one hopefully new tyre helps sort it .

[Del]

Well MOT done n dusted for another year - mentioned to the fella who mot'd it (happens to be a mate as well  )about the wobble and we put it back on the brake tester - he did say that there was a slight but if run out on the tyre - so new tyre ordered and Ill get it Tuesday - fingers crossed

[seth]

 
good luck buddy

[Andre]

good to have mates 

[Nellywelly]

I had the same problem. Found the front tyre was the cause it was a maxxis crap. I didn't fit it previous owner did. I wouldn't put maxxis on a wheel barrow!
Pilot road 4 fitted now, perfect! 

[gsxbarmy]

Well MOT done n dusted for another year - mentioned to the fella who mot'd it (happens to be a mate as well  )about the wobble and we put it back on the brake tester - he did say that there was a slight but if run out on the tyre - so new tyre ordered and Ill get it Tuesday - fingers crossed

So did you get your tyre today Del - problem now solved (hopefully)?

@Del

[Del]

@gsxbarmy

No not yet mate this week hopefully -been keeping bike below 70 till I can get to garage . . . . . .wife's car needed a dual mass clutch so that took care of £600.00