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NC30 Front Fork Knock
Posted: Wed Mar 09, 2011 6:37 pm
by samace
Re: NC30 Front Fork Knock
Posted: Wed Mar 09, 2011 10:08 pm
by Cammo
It looks to me like it's just missing the dust covers. Some racers remove them so there's less friction on the sliders. Removing it won't change the operation of the forks.
When does it knock?
Re: NC30 Front Fork Knock
Posted: Wed Mar 09, 2011 10:11 pm
by CMSMJ1
sack off that gash fork brace too...lol
a waste of unsprung weight! Soichiro Honda will be spinning in his grave!
Re: NC30 Front Fork Knock
Posted: Wed Mar 09, 2011 10:19 pm
by porndoguk
CMSMJ1 wrote:sack off that gash fork brace too...lol
a waste of unsprung weight! Soichiro Honda will be spinning in his grave!

Re: NC30 Front Fork Knock
Posted: Wed Mar 09, 2011 10:29 pm
by samace
Cammo wrote:It looks to me like it's just missing the dust covers. Some racers remove them so there's less friction on the sliders. Removing it won't change the operation of the forks.
When does it knock?
That is not the case as there is rubber on top connected to the seal its in one piece so there is no cover there is nothing but interference fit holiding seals in ?
Re: NC30 Front Fork Knock
Posted: Thu Mar 10, 2011 2:29 am
by Morespeedvicar
Hi, i've not look at the seals on my nc but the proper seal is usually held in by a wire type circlip, the dust seals are just pushed in, there not very tight fit on the stantion so dont need clipping in. But could somebody of just put in a proper seal in place of the dust seal for a quick 'forks are leaking i got a race in the morning' type bodge!
Cheers
Ian
Re: NC30 Front Fork Knock
Posted: Thu Mar 10, 2011 9:56 am
by amorti
Usually a knock means either your head bearings are loose/worn, or you need new fork bushings. The other one I had once was on a Triumph where the disc bobbins were loose, that had me foxed for a while.
Has the seller sold you bits that are a tiny bit duff, perhaps? Seems to me like they are missing dust caps, have had some sort of bodge on he fork seals and if my guess is right also want new bushings. It's not the end of them if they're straight and the chrome's okay but the 4 bushings will set you back ITRO £19 + VAT + P&P from David Silver:
http://www.davidsilverspares.co.uk/CBR4 ... art_11094/
http://www.davidsilverspares.co.uk/CBR4 ... art_11095/
Oil seals are £11 + VAT + post there, Dust seals £15.50 + VAT + post, but you can get reasonable quality Pyramid parts on eBay for ~£17 for all 4, delivered.
You can spot duff fork bushings by getting the front wheel off the floor, holding fork lowers tightly and wobbling, if you can see movement at all, they want changing. They often get neglected but they are definitely a consumable item and your bike will handle better for changing them - less play and less "stiction" as when they wear, it's the teflon coating which gives out first. Since you would put new oil in at the same time there is another small benefit to be had.
Re: NC30 Front Fork Knock
Posted: Thu Mar 10, 2011 7:19 pm
by samace
I have just had an email back from reactive suspension saying not to ride the bike as the seal may pop out as there seem to be nothing holding them in ? The bit you see in the picture on top of fork leg is all conected to the seal.

Re: NC30 Front Fork Knock
Posted: Fri Mar 11, 2011 8:49 am
by amorti
samace wrote:I have just had an email back from reactive suspension saying not to ride the bike as the seal may pop out as there seem to be nothing holding them in ? The bit you see in the picture on top of fork leg is all conected to the seal.

I would tend to go with that, until you have stripped it all down - you have no idea what's in there or if it's safe.
Re: NC30 Front Fork Knock
Posted: Fri Mar 11, 2011 6:30 pm
by samace
Took forks off, when you pull and push the stanchion there is a slight knock. I have ordered all new genuine honda bushes, seals, dust covers and clips to hold seals in. Have I forgot any thing ? (will get oil locally).
