Dirtcrasher
05-07-2010, 09:30 PM
It comes up allot, I've posted this in threads abut never made a fresh topic about it.
Some may or may not agree, but if done as posted you will not harm anything.......
Not EVERYONE has V-blocks and a dial indicator setup.
Jack it up and get the front tire an inch of of the ground.
Remove the upper fork boot clamp or plastic strap and lower it as low or SQUASHED as you can get it.
Loosen all 8 pinch bolts (or whatever) and make sure they are about 1/8th inch loose or away from where they would lock down on the triple clamp. I usually take the top bolt out completely and angle my screwdriver down.
Get 2 flat head screwdrivers that will fit in the "gap".
GENTLY tap them in to spread the open aluminum just a hair; Any more isn't needed. If you spread them too much, the leg starts to drop out and the aluminum is weekend; You run the risk of snapping the ear off. Just a gentle tap until it turns is all you need.
Try one side at a time and barely tap/tighten them in until the upper tube can be rotated by hand.
Rotate the upper fork tube by hand, may require a bit more tapping of the screwdrivers. Do not hit the chrome portion of the tube while doing this, just angle the screwdriver. I use 2 identical medium sized screwdrivers.
As it turns, with the wheel slightly off the ground, you will see the wheel/axle change angles or the lower fork leg moving back and forth or in a circle.
If they remain straight, your good :beer
If they do as suggested above, then the upper chrome tube is bent. It isn't the end of the world, MANY trike forks are bent! The 200X fork seems to bend very easy after a crash/roll etc etc.
A good machinist/mechanic can fix them with 3 V-blocks and a 10-20 ton press or even an arbor press. If they are just a bit bent, there won't be an issue bending them back. If they are kinked or that wheel moves like crazy! when you rotate it, it's best to get another set of forks or good upper tubes. I've been amazed at how much it changes the wheels axle location when there bent pretty good!
Another method of (careful gap spreading) is to use a fully threaded bolt and thread it in from behind. Place a penny in the "gap" and thread the bolt in until it touches the penny, then tighten it a hair more or until the gap spreads a bit (DON'T OVER DO IT!!) Then you can rotate the tube as suggested above. This is the same method I use to "spread" rear axle carrier pinch bolts so I can tap the axle carrier out without damaging it.........
The problem is that some or many upper fork tubes are pitted with rust. If the rust is within the triple clamps, then it's merely a cosmetic issue. If they are pitted under the fork boot then they eat up seals pretty quick.
How to unbend them is a whole other Topic. I can usually get them very close in my shop or if you are equipped (or have a bud with the goodies - 3 V-blocks and a good indicator) you can do it yourself.
Of course the best way is to disassemble them and put the upper tube in 2 V-blocks using a dial indicator. But not everyone can do that, yet they still want to know how to identify "bent forks"!!
Follow the directions above and I hope it helps some guys figure out whats going on!
DC
Some may or may not agree, but if done as posted you will not harm anything.......
Not EVERYONE has V-blocks and a dial indicator setup.
Jack it up and get the front tire an inch of of the ground.
Remove the upper fork boot clamp or plastic strap and lower it as low or SQUASHED as you can get it.
Loosen all 8 pinch bolts (or whatever) and make sure they are about 1/8th inch loose or away from where they would lock down on the triple clamp. I usually take the top bolt out completely and angle my screwdriver down.
Get 2 flat head screwdrivers that will fit in the "gap".
GENTLY tap them in to spread the open aluminum just a hair; Any more isn't needed. If you spread them too much, the leg starts to drop out and the aluminum is weekend; You run the risk of snapping the ear off. Just a gentle tap until it turns is all you need.
Try one side at a time and barely tap/tighten them in until the upper tube can be rotated by hand.
Rotate the upper fork tube by hand, may require a bit more tapping of the screwdrivers. Do not hit the chrome portion of the tube while doing this, just angle the screwdriver. I use 2 identical medium sized screwdrivers.
As it turns, with the wheel slightly off the ground, you will see the wheel/axle change angles or the lower fork leg moving back and forth or in a circle.
If they remain straight, your good :beer
If they do as suggested above, then the upper chrome tube is bent. It isn't the end of the world, MANY trike forks are bent! The 200X fork seems to bend very easy after a crash/roll etc etc.
A good machinist/mechanic can fix them with 3 V-blocks and a 10-20 ton press or even an arbor press. If they are just a bit bent, there won't be an issue bending them back. If they are kinked or that wheel moves like crazy! when you rotate it, it's best to get another set of forks or good upper tubes. I've been amazed at how much it changes the wheels axle location when there bent pretty good!
Another method of (careful gap spreading) is to use a fully threaded bolt and thread it in from behind. Place a penny in the "gap" and thread the bolt in until it touches the penny, then tighten it a hair more or until the gap spreads a bit (DON'T OVER DO IT!!) Then you can rotate the tube as suggested above. This is the same method I use to "spread" rear axle carrier pinch bolts so I can tap the axle carrier out without damaging it.........
The problem is that some or many upper fork tubes are pitted with rust. If the rust is within the triple clamps, then it's merely a cosmetic issue. If they are pitted under the fork boot then they eat up seals pretty quick.
How to unbend them is a whole other Topic. I can usually get them very close in my shop or if you are equipped (or have a bud with the goodies - 3 V-blocks and a good indicator) you can do it yourself.
Of course the best way is to disassemble them and put the upper tube in 2 V-blocks using a dial indicator. But not everyone can do that, yet they still want to know how to identify "bent forks"!!
Follow the directions above and I hope it helps some guys figure out whats going on!
DC