hollow front end knock...

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royster81
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hollow front end knock...

Post by royster81 »

...when the forks go over bumps ?
what could this be down too ? head bearings,worn bushes in the forks,knackered wheels bearings(i'm almost 100% sure the wheels bearings are fine)
the bike rides 100% great but when the forks roll over a bump i can feel and hear this hollow knock,but there is no movement under braking (none that i can tell)...

so guys what do you think?
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Jon
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Re: hollow front end knock...

Post by Jon »

How firm are the plastic rings that hold your front gaurd onto your forks, drove me nuts trying to find it and was as you described, smear of silicone on the inside of the rings and all good.

regards
jon
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lee_
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Re: hollow front end knock...

Post by lee_ »

My guess would be head bearings, but floating discs can rattle a bit too.
viper_biker
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Re: hollow front end knock...

Post by viper_biker »

Having also ridden the bike in question, I'm agreeing with Jon.
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aaron0288
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Re: hollow front end knock...

Post by aaron0288 »

+1 for Jon and viper. mine does exactly the same.
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Sligeach
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Re: hollow front end knock...

Post by Sligeach »

mine did it too before i binned it.
when i got a new mudguard and rings it sorted it out a treat. although when i replaced them i did put a little something in to make up the extra space that was there. seems to have sorted it
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royster81
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Re: hollow front end knock...

Post by royster81 »

ok ,i'll try the "loop of electrical tape" trick around the guard holder rings on the forks and give it another run out,any excuse to get a few more miles ....
It's not having what you want but wanting what you've got....Loud ,Proud and Modified ....
colingram
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Re: hollow front end knock...

Post by colingram »

Hey Royster,

my bike did exactly the same before the feckers nicked it. There are 2 lock rings under the top yoke which tighten down on the top head bearing. They work themselves loose after a while and cause the steering stem to knock about a bit over bumps and potholes etc. The sound does seem to come from the forks and I used it as an excuse to rebuild the forks with new bushes etc and a full caliper rebuild. If you pull the top yoke off and tighten up the two lock rings with a drift, that should hopefully cure the knocking (if you have no joy with the guard holders that is)
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royster81
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Re: hollow front end knock...

Post by royster81 »

colingram wrote:Hey Royster,

my bike did exactly the same before the feckers nicked it. There are 2 lock rings under the top yoke which tighten down on the top head bearing. They work themselves loose after a while and cause the steering stem to knock about a bit over bumps and potholes etc. The sound does seem to come from the forks and I used it as an excuse to rebuild the forks with new bushes etc and a full caliper rebuild. If you pull the top yoke off and tighten up the two lock rings with a drift, that should hopefully cure the knocking (if you have no joy with the guard holders that is)
i was thinking it was going to be this ...
suppose i'll have to ask to borrow the big socket set again ..........gareth ..oh gareth old buddy old pal......
It's not having what you want but wanting what you've got....Loud ,Proud and Modified ....
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Jon
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Re: hollow front end knock...

Post by Jon »

To check your headstock bearings stand beside your bike and pull on the front brake, try pushing your bike back and forth, if your headstock bearings are loose you should be able to see/hear/feel the movement.

regards
jon
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