Fork stanchion repair

Moderators: trixynut, Mincehead, dicky, phuk72, Jak, Kevtrx849

Post Reply
User avatar
drix
Site Sponsor
Posts: 555
Joined: Wed Apr 16, 2008 9:25 pm
Location: London/Surrey - UK & Valenciennes - FR

Fork stanchion repair

Post by drix » Sun Apr 10, 2016 5:41 pm

Hi guys

My second TRX came with a set of Thundercat forks fitted and after blowing two seals in very little time, I took a closer look to the stanchion and here is what I found:

Image

Is a home repair possible here (if so, how/which techniques?) or should I go down a rechroming/professional repair or source another set of forks?

Cheers
Adrien

User avatar
Snod Blatter
TRX-Enthusiast
Posts: 405
Joined: Sun Sep 16, 2012 8:40 am
Location: Worksop, UK

Re: Fork stanchion repair

Post by Snod Blatter » Sun Apr 10, 2016 6:01 pm

I know this doesn't answer your question (sorry!) but I wouldn't expect that to give any trouble at all. Are you using NOK seals or rubbish from somewhere else?

On topic: Some people have filled little nicks with superglue or epoxy such as Araldite. It's a definite bodge though, can't expect it to last a long time.
'95 4NX with K&N filter, Motad Venom cans, YSS PD valves, Ohlins fork springs, 530 C+S, Green CDI, 11/16 radial master cylinder, +30mm jack up dog bones. Enjoyable money pit.

User avatar
drix
Site Sponsor
Posts: 555
Joined: Wed Apr 16, 2008 9:25 pm
Location: London/Surrey - UK & Valenciennes - FR

Re: Fork stanchion repair

Post by drix » Sun Apr 10, 2016 6:17 pm

Haven't used OEM seals here.

It's got a slight sharp edge to it and is more or less where the seal sits so it is an issue, I'm guessing a screwdriver/hammer was used in the past to fit the seal in it's place but must've slipped.. :?
Last edited by drix on Sun Apr 10, 2016 7:56 pm, edited 1 time in total.

User avatar
Snod Blatter
TRX-Enthusiast
Posts: 405
Joined: Sun Sep 16, 2012 8:40 am
Location: Worksop, UK

Re: Fork stanchion repair

Post by Snod Blatter » Sun Apr 10, 2016 6:50 pm

Right, I understand the picture a bit better now. I don't really know what you could do about that, the normal bodges are for filling in pits not repairing damage like that.

You could get a replacement stanchion, Wemoto seem to be selling them for £112.50. No idea how much rechroming is, bet it's about the same though!
'95 4NX with K&N filter, Motad Venom cans, YSS PD valves, Ohlins fork springs, 530 C+S, Green CDI, 11/16 radial master cylinder, +30mm jack up dog bones. Enjoyable money pit.

User avatar
highlander
Site Sponsor
Posts: 248
Joined: Sun Mar 20, 2011 4:55 pm
Location: Highlands

Re: Fork stanchion repair

Post by highlander » Sun Apr 10, 2016 7:43 pm

You can get a better price (~£140 for both) if you are happy to strip and rebuild yourself, send stripped stanchions to people such as:

http://www.dynasurf.co.uk/motorcycle-forks

http://www.brooksuspension.co.uk/motorc ... -legs.html
Projection Racing 2-1 with Akropovic hex carbon can, Keihin FCRs @ 150 main, R6 shock conversion, 520 chain conversion, Ignitech ignition, Li-po battery. Further weight reduction & front suspension in progress ....

User avatar
drix
Site Sponsor
Posts: 555
Joined: Wed Apr 16, 2008 9:25 pm
Location: London/Surrey - UK & Valenciennes - FR

Re: Fork stanchion repair

Post by drix » Sun Apr 10, 2016 8:08 pm

Rechroming sounds like the better/trouble free option and can take of the stripping/rebuild myself. Sanding the sharp edge down would still leave me with a small gap and epoxy/loctite filling sounds like a real bodge. :?

The stanchion is upside down on the photo btw ;)

User avatar
dicky
Site Sponsor / Administrator
Posts: 1028
Joined: Thu Jan 06, 2005 11:26 am
Location: Ruffy, Victoria.

Re: Fork stanchion repair

Post by dicky » Mon Apr 11, 2016 12:35 am

drix wrote:The stanchion is upside down on the photo btw ;)
:shock:
If it was right way up I'd believe the bit about slipping with a screwdriver while driving in the seals.
Being upside down makes me think that the fork has hit something, rather than something has hit the fork.
If you've got the fork pulled apart you might want to check if the stanchions are still straight.
dicky
OOOSDC #5

User avatar
Mincehead
TRX-Enthusiast
Posts: 6345
Joined: Sun Jan 25, 2009 1:40 pm
Location: West Sussex
Contact:

Re: Fork stanchion repair

Post by Mincehead » Mon Apr 11, 2016 7:50 am

drix wrote:Hi guys

My second TRX came with a set of Thundercat forks fitted and after blowing two seals in very little time, I took a closer look to the stanchion and here is what I found:

Image

Is a home repair possible here (if so, how/which techniques?) or should I go down a rechroming/professional repair or source another set of forks?

Cheers
Adrien
Dress the stanchion with an oil stone, then blend it in with fine grade wet and dry. If there`s an area `under diameter` Dremel it a little deeper, leave the area rough and fill with a good car body filler. After it`s cured dress it down again to stanchion diameter and it`ll last quite a while, (I know folk who run gaiters over filled stanchions that have been done years) giving you time to find another stanchion or organise re-chroming and grinding of the original :wink: .
LOUD PIPES SAVE LIVES

User avatar
dandywarhol
Site Sponsor
Posts: 1639
Joined: Fri Nov 24, 2006 12:56 pm
Location: Edinburgh, Scotland

Re: Fork stanchion repair

Post by dandywarhol » Wed Apr 13, 2016 11:15 pm

Dress it and fill with Araldite epoxy resin. When fully cured, smooth down with 800/1000 grit wet or dry paper until you can't feel it with your nail. Done loads of trials bike forks that way and they get a harder time than a road bike. :D
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

User avatar
drix
Site Sponsor
Posts: 555
Joined: Wed Apr 16, 2008 9:25 pm
Location: London/Surrey - UK & Valenciennes - FR

Re: Fork stanchion repair

Post by drix » Wed Apr 20, 2016 10:35 am

I decided to avoid any filling for now and gently smoothed the scratch instead with some 1200 grit wet & dry. It's been holding up fine for 150miles so far and the upper part of the stanchion has remained oil free... Let's see how it goes on the longer run. :D

Post Reply