I am attempting to do a fork upgrade as the excellent write up in knowledge base and all was going swimmingly until I attempted to get the bottom bolts out of the fork lowers. I have gently used an air impact gun and sadly rounded one but the other has come undone and just spins. I've read the best way to remove the one that is spinning in the valve but the one that I have rounded presumably I am just going to have to drill out? The ease at which it rounded I take it the material is soft?
Also, until I get the bolts out I am right in saying that the stantion won't come out to make replacing the seals easier?
Thanks and apologies if this has either been covered or is a stupid question!
Bottom fork bolt grief
Re: Bottom fork bolt grief
Mmmm you have run into the same problem others have. Did you see the following posts from Diabolus:
http://www.vtr1000.org/phpBB3/viewtopic ... 30#p315670
If the hex head is totally rounded then maybe it would be worth hammering a bigger Hex head into it. Have you tried an impact driver? (non air) Maybe a little heat would help. Drilling it out would be the last option IMO
But........the good news is, that you don't have to totally remove the stanchion to only change the fork seals. You could carefully drill a hole in the seal and then get an angle pick/lever in there and prise them out. You can even still change you fork oil. All removing the compression damper cartridge does, is allow you to totally separate the stanchion from the fork lower and allow access to the internal valving within the damper.
It would certainly make life easier if you could remove the stanchion but it's not totally necessary for doing the fork seals. Don't forget to remove the C clip above the fork seals first.
(:-})
http://www.vtr1000.org/phpBB3/viewtopic ... 30#p315670
If the hex head is totally rounded then maybe it would be worth hammering a bigger Hex head into it. Have you tried an impact driver? (non air) Maybe a little heat would help. Drilling it out would be the last option IMO
Yes. The internal compression damper cartridge slides inside the stanchion and the bolt goes through the base of both of them, though it only bolts into the cartridge. You can slide the Stanchion up as far as the small spring at the top of the cartridge, it wont get past that without totally removing the cartridge via the bolt first. This also means you can't totally remove the stanchion from the leg.Also, until I get the bolts out I am right in saying that the stantion won't come out to make replacing the seals easier?
But........the good news is, that you don't have to totally remove the stanchion to only change the fork seals. You could carefully drill a hole in the seal and then get an angle pick/lever in there and prise them out. You can even still change you fork oil. All removing the compression damper cartridge does, is allow you to totally separate the stanchion from the fork lower and allow access to the internal valving within the damper.
It would certainly make life easier if you could remove the stanchion but it's not totally necessary for doing the fork seals. Don't forget to remove the C clip above the fork seals first.
(:-})
==============================Enter the Darkside
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mattycoops43
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- Joined: Sun Apr 07, 2013 12:02 am
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Re: Bottom fork bolt grief
It is necessary if you want to clean all the old crap and ali filings out of the bottom of the fork leg and if you want to set the air gap correctly.
Budget storm gradually on the road to spangliness.
Re: Bottom fork bolt grief
Hi,
I had a similar problem a while back with some cr250 forks.
What I did was put a suitable bolt in the lower fork then clamp a spare or removed top yoke to the station then fasten a lorry strap to both ends & compress the whole lot until there is too much pressure internally for the control rod inside to spin.
If you do get something to turn the now knackered Allen hex, use a heat gun to soften/kill any thread lock previously applied. Don't laugh, those heat guns are fab for things like this.
BTW, If it goes wrong & you hurt yourself! My friends uncle's brother, three fingers Pete from back yonder taught me this trick.....
Regards.
I had a similar problem a while back with some cr250 forks.
What I did was put a suitable bolt in the lower fork then clamp a spare or removed top yoke to the station then fasten a lorry strap to both ends & compress the whole lot until there is too much pressure internally for the control rod inside to spin.
If you do get something to turn the now knackered Allen hex, use a heat gun to soften/kill any thread lock previously applied. Don't laugh, those heat guns are fab for things like this.
BTW, If it goes wrong & you hurt yourself! My friends uncle's brother, three fingers Pete from back yonder taught me this trick.....
Regards.
Re: Bottom fork bolt grief
Don't forget the inner fork bushIt is necessary if you want to clean all the old crap and ali filings out of the bottom of the fork leg and if you want to set the air gap correctly.
Yeh if the OP wants to clean things out thoroughly including the internals of the compression damper then yes a total strip down is needed. Oil, damper bleeding and air gap can still be done though.All I'm saying is that the fork seals can be done without removing the stanchion if needs be. Not the best way to change them but it can be done. The bottom bolt may turn into something that the OP may prefer to leave as is.
(:-})
==============================Enter the Darkside
Re: Bottom fork bolt grief
i had the same problem on my fork
i built the fork back up and did like varasrorm said only i used my body weight
which was enough, but like varastorms idea of using a strap it would be easier
i built the fork back up and did like varasrorm said only i used my body weight
which was enough, but like varastorms idea of using a strap it would be easier
told you not to but oh no you knew better
Re: Bottom fork bolt grief
Thanks for the info chaps, all apart now no problem. Had to drill bolt out on one leg which was very easy with a cobalt drill set, took a few minutes. Luckily no damage and new bolts and washers ordered.
Whilst I have it stripped I've noticed the original steering head bearings are very notchy in the straight ahead position so have ordered new taper bearings and seals.
Hopefully with new Ktech linear springs and other mods no more bottoming out!
Thanks again for advice.
Whilst I have it stripped I've noticed the original steering head bearings are very notchy in the straight ahead position so have ordered new taper bearings and seals.
Hopefully with new Ktech linear springs and other mods no more bottoming out!
Thanks again for advice.