Front end knock after fork seals
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Front end knock after fork seals
Hi gang.
I've got something new to me here... i changed the fork seals which all went according to plan, until I test rode the bike... There is now a awful clunk on comp and rebound over sharp bumps/potholes.
The only thing I've done differently to the past is I put new bushes in (Which i nevr bothered with in the past, but thought I might as well this time). The one that clips on the end of teh stanchion and the one that sits below the washer below the seal. The thing that DID worry me slightly was that the number stamped into the side of the top bush (in both forks) was different to the old one. I looked up the actual part number onthe packet and cross checked it against some info online and it looked to be the right one. It seated properly with no dramas and visually looked the same.
Stupidly, i threw the old ones out, thinking that having bought genuine parts from a yamaha dealer they should be right.
anyway, ive had them apart again just to make sure there is nothing i did wrong and I cant see anything obvious. The internals are, from top to bottom, under the top caps:
4 washers
Clear plastic spacer
Another washer
Aluminium spacer
another washer
Another spacer
Another washer
Springs (shorter/stiffer than stock but have been in there with no worries for the last 2 seal changes)
Damper rod.
So, assuming that the bushes ARE correct... any ideas as to what could be causing this thunk?
When stationary and pressing the forks down it sounds as though they bottom out.. there is a creak and then a knock. I've got a blend of 10w and 15w oil at the correct level. Leaning further toward 15w. The oil i took out was full 15w which had performed well.
hoping you can save me a trip to the bike shop.
oh, with the weight off the front i've wiggled the forks and cant feel any free play anywhere. not in the stem or the tubes
I've got something new to me here... i changed the fork seals which all went according to plan, until I test rode the bike... There is now a awful clunk on comp and rebound over sharp bumps/potholes.
The only thing I've done differently to the past is I put new bushes in (Which i nevr bothered with in the past, but thought I might as well this time). The one that clips on the end of teh stanchion and the one that sits below the washer below the seal. The thing that DID worry me slightly was that the number stamped into the side of the top bush (in both forks) was different to the old one. I looked up the actual part number onthe packet and cross checked it against some info online and it looked to be the right one. It seated properly with no dramas and visually looked the same.
Stupidly, i threw the old ones out, thinking that having bought genuine parts from a yamaha dealer they should be right.
anyway, ive had them apart again just to make sure there is nothing i did wrong and I cant see anything obvious. The internals are, from top to bottom, under the top caps:
4 washers
Clear plastic spacer
Another washer
Aluminium spacer
another washer
Another spacer
Another washer
Springs (shorter/stiffer than stock but have been in there with no worries for the last 2 seal changes)
Damper rod.
So, assuming that the bushes ARE correct... any ideas as to what could be causing this thunk?
When stationary and pressing the forks down it sounds as though they bottom out.. there is a creak and then a knock. I've got a blend of 10w and 15w oil at the correct level. Leaning further toward 15w. The oil i took out was full 15w which had performed well.
hoping you can save me a trip to the bike shop.
oh, with the weight off the front i've wiggled the forks and cant feel any free play anywhere. not in the stem or the tubes
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Re: Front end knock after fork seals
Put a cable tie around your fork leg push down on a fork and just measure how much travel you have Jim...
laughter is the best medicine
- dandywarhol
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Re: Front end knock after fork seals
Not directly linked but I'd recheck the steering head bearings adjustment
1996 TRX 850, blue, Ohlins 46HRCLS, Race Tech Gold Valves, 0.90 springs, Venom pipes, R6 brakes............
1974 Yamaha RD250A, Candy Blue
1998 Yamaha SZR660, blue of course
1967 Yamaha TD1C 250, Blue and white
1974 Yamaha RD250A, Candy Blue
1998 Yamaha SZR660, blue of course
1967 Yamaha TD1C 250, Blue and white
- Con Rod
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Re: Front end knock after fork seals
Are your brake pads moving in the calipers?
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Re: Front end knock after fork seals
undo fork leg lower pinch bolt - one one on the wheel spindle, pump fprks a couple of times keeping the bike upright, then retighten the pinch bolt.
Does the noise still persist?
Does the noise still persist?
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Re: Front end knock after fork seals
Thanks for all the suggestions people... I ah, actually thought I'd um... deleted this post, cos um... well... embarrassingly, it was the top triple centre nut was loose... But hey, its not like I pulled the forks off and went through the entire process a second time or anything...
- Silver
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Re: Front end knock after fork seals
Don't be too embarrassed, I got the seals in upside down!.
2010 Street triple R 675 Road bike
2018 BMW G310GS
1988 Honda XBR500(converting to GB500 spec)
SZR660 road and track project
2018 BMW G310GS
1988 Honda XBR500(converting to GB500 spec)
SZR660 road and track project