hi
i need to service my front forks which are leaking a bit and are soft. any advice appreciated
thanks
mj
gt380 front forks need some attention
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Re: gt380 front forks need some attention
Seals need replaced. Super easy to do. Remove forks, remove old oil, pry gently up on the dust cover boots to remove them, remove allan bolt on each fork bottom, remove fork cylinders by tugging on them until they bypass the seals. Remove old seals with a flat head screwdriver and a pair of vise grips being careful not to gouge the inner liner of the fork leg. Once removed, pop the new ones in facing the same direction the old ones were. Assemble everything back together, fill with the correct amount of oil and you're done. About a 1- 2 hour job, depending on your speed. Your forks may feel too soft depending on your weight or too much oil may have been pushed out pass your seals. Maybe a combination of both. I used 15-40 motor oil to fill mine and I like how firm they feel. My weight is 180 pds.
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Re: gt380 front forks need some attention
First make sure the inner tubes haven't got nicks or deep scratches in them other wise you are wasting your time changing your fork seals.
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Re: gt380 front forks need some attention
Good point.parksie wrote:First make sure the inner tubes haven't got nicks or deep scratches in them other wise you are wasting your time changing your fork seals.
Martin - given your location, if they are pitted or scratched, you can sometimes use epoxy to fill the pits if there are not too many or if they are not too deep. Something like JBWeld - over your way it might be called Araldite possibly, or maybe Devcon. Get the pit super clean, fill with epoxy, let cure, sand down flush with 1000 or finer grit paper.

Ian
If at first you don't succeed, just get a bigger hammer !
If at first you don't succeed, just get a bigger hammer !
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Re: gt380 front forks need some attention
thanks for all that. But,,,er,,,how do you actually remove the forks themselves? It is not so evident from the posts.
many thanks for your patience, all of you
mj
many thanks for your patience, all of you
mj
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Re: gt380 front forks need some attention
If you don't have the proper stands. I found a very easy way to work on the front end of these bikes. I have the proper stands and I still use this method because it's so much easier. Remove the back wheel first. If your bike has the center stand you can then lift the front of the bike until the rear swing arm rests on the floor. It will jack the front of the bike nice and high. Then remove the front wheel, fender and axle. The only thing you need to do from that point is completely remove all 4 pinch bolts on the upper and lower triple trees that hold the fork legs in place. I can't remember which size, but grab the same size diameter socket as the upper fork cylinders. Place that socket on top of the fork cylinders after you remove the rubber grommet and tap them down a little at a time until the forks pop out the triple trees. Be sure to hold the fork with one hand, while tapping from the top with the other. Otherwise, they will hit the floor and get damaged or fall against the bike doing other damage to it. Release spring tension with allan bolt on bottom of fork after you drain oil with small screw on side of fork. Take C-clip pliers, remove C clip at top of fork cylinders. Gently tap forks downward onto a padded surface and the top lid will eventually pop off. DO NOT HAVE YOUR FACE DIRECTLY ABOVE THE FORK CYLINDERS. Spring tension could shoot the caps in a hard manner into your face. But, as long as you avoid that and remove allan bolts at bottom of forks to relieve tension. It's a very easy job and difficult to screw up.Ramjam wrote:thanks for all that. But,,,er,,,how do you actually remove the forks themselves? It is not so evident from the posts.
many thanks for your patience, all of you
mj
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Re: gt380 front forks need some attention
So, after reading your guide and looking at the manual, the first stage is really simply. Just undo the clamps at the top of the forks and the bolts on each fork and individually each fork should 'fall' through, right? at that stage, the forks are still under tension and sill very much together, yes?
thanks a lot, PJ. Very useful and kind. Let's see if i dont screw up.
MJ
thanks a lot, PJ. Very useful and kind. Let's see if i dont screw up.
MJ
Last edited by Ramjam on Wed Nov 13, 2013 12:53 pm, edited 1 time in total.
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Re: gt380 front forks need some attention
No problem. These fork cartridges ( what's inside ) are extremely simple. Just take your time. Most important thing is the amount of oil you add. The amount has to be spot on to what the manufacturer suggests. Otherwise there will be too much or too little compression when you go to install the cap back onto the spring. If you get in a bind, I and others can help. I'm on here daily. Oh, I forgot. If you use my method for lifting the front of the bike. The exhaust will have to be removed also. Or you can spend $100 for a nice bike jack that lifts the bike completely off the ground. But, with it. The exhaust still needs to be removed. So, for front end work. I like the method I mentioned first.Ramjam wrote:thanks a lot, PJ. Very useful and kind. Let's see if i dont screw up.
MJ