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front forks Q

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K, so my 2007 CRF250x forks have been leaking oil, slowly for some time.  I tried the plastic thing etc and it seemed to work, but they still leak.  Now, they leaked all over the brake and screwed it up.  No big deal, I'll just take it apart and (I HATE THIS WEB SITE!!!!! SO SLOW!!!!!!!!)  sorry, clean it.

 

The question is, should I rebuild the front forks myself?  What would it cost to send them out?  How hard is it?  I've done a head and changed tires etc  The Youtube vid looks OK., just teadious.

 

Can I measure and top them off?

 

Thanks Again,

TomJV

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You probably can do the seal/bushing rebuild but I would suggest a shop manual and some research on TT, and use Honda seals,  a kit is avail that includes bushings.  I recommend RaceTech cartridge fork oil or Motorex Racing 2.5wt @ cycle gear, similar weight oil.

Edited by Chuck.

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Changing fork seals and fluid isnt real difficult but the first time can be alittle confusing and theres a couple of tools you might not have.

The owners manual has alot of good information about it and some photos that will really help. Also look at the fork tubes closely to check for nicks or any scratches, if you find any make sure to smooth them out.

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I had a set of USD forks that one seal was leaking, I found two bruise marks on one slider, probably from a collision.  I polished the bruises with a dremel and polishing compound, switched the seal to the other leg and have been good for 3 years.

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Thanks guys,

 

The issue is, I'm going on a trip soon and would like to do the maintenance later.

I'll certainly inspect them etc.

I'm wondering how to tell if this is "critical" at this point.  The forks seem pretty firm, like I just tried to compress them and they moved an inch, maybe.  LOW oil would be saggy, right?

 

I've found a couple of 3" puddles under them over the last couple years.  Nothing major.  I did the plastic cleaning trick which seemed to help.

Is it possible I could take them off, measure the heights, equalize/top off and do the rebuild in August after my trip?

We'll do 3-4 days of 50miles.

The bike has 65 hours of trail riding on it and is maintained and clean.

 

I'm just looking for a best guess here.

Thanks again!

TomJV

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The reason the damping still feels good is the forks have sealed cartridges that will retain their oil, any oil loss will be from the outer chambers that lube the bushings and provides bottoming resistance via air cushion. Oil loss will first affect bottoming resistance.

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If you have the tools as mentioned above (seal driver, tusk wrench) it will take you one night. And that was my first time too. Could also make your 200 mile trip a lot more comfortable.

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Can someone show me which wrench is best.  I searched the Tusk wrench(3pc tool) but it only specifies 450x.

Gonna borrow a seal driver.

TomJV

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Thank you guys,

So, are the fork tops 50mm?

TomJV

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I did my front forks on my 2006 CRF250X.

The job took me several hours, but I didn't care.  I just took my time and it came out fine. 

Thanks to all who offered advice!

 

There are several considerations with doing forks. Tools, Expertise, Parts.

 

Tools:  I wound up doing the job with no special tools and it came out fine.  If I had it to do over, I'd certainly opt to HAVE the tools, but I needed the job done and that's how things shook out.

 

Fork Seal Driver - I was supposed to borrow one, but the deal fell thru.  I would up using two methods;

1. Home-Made Driver out of PVC.  This worked OK, but my PVC was a thin schedule and I was worried it would damage the seal.  I wound up using method #2. Old Seal method.  I used my PVC tool with an old seal and drove the new ones in.  I checked my work with a flat headed drift.  You can hear when they're home.  The clip went right in both times.

Fork Top Wrench - I went on Amazon and bought the 50mm Motion Pro wrench #08-0428.  Very nice quality wrench but unfortunately, it doesn't fit my CRFs.  The size appears correct, but the shape is all wrong.  I wound up using an open-end SAE wrench I had.  I was careful not to damage the tops and they were not very tight either.  Also, I didn't "kill them" going back in.  I think the top pinch bolts hold them anyway.

Inner Tube Holder - The Motion Pro wrench worked fine for this.  I wouldn't recommend using an open end wrench here.  I can see that thing coming loose and damaging your forks.  You can make one out of a piece of aluminum and a table saw in 15min.

Fork Seal Bullet - You can buy the Motion Pro tool on Amazon for $7.  This is a tool that allows you to slide the new bushings onto your forks without damaging them.  The forks are not entirely smooth and straight.  There are a couple of shoulders you have to go over to get the seals on. It's a tight fit.  They are machined very square, so-much-so that they are sharp.  I used a plastic bag with some WD40 on it and it worked fine.  The bag should be thicker than an ordinary "food storage" bag.  I found it too thin to provide protection.  I wound up with a heavier "zip lock" type.  Don't forget to lube it.

Graduated Cylinder - The book shows the guy measuring the new fork oil with great precision using a graduated cylinder.  (I haven't used one in 30 years LOL)  Anyway, I took it to heart and went on Amazon and bought the "amico lab set 500ml".  It was only $8 and worked out great.  Truth be told, you don't need one.  when you fill the inner tube, you basically fill it to the top and any extra will overflow.  When you fill the outer tube, you use a ruler to verify the height.  The graduate puts you right in the money so you don't make a mess, so I'd get one.

Vise, Torque Wrench etc - It's barely worth mentioning because all shops should have this stuff, but you'll definitely want to have a vise and soft jaws or rags.  The forks can be pretty difficult to hold, even with two guys.  Of course, you'll need a torque wrench, mostly to re-assemble the pinchbolts and handlebars.  Otherwise, nothing in there that I saw was torque critical.

 

Expertise:  I found the job straightforward.  It took me about 6 hours with a trip or two to the store, lunch and stopping to view videos frequently.  I also let my tubes drain upsidedown for quite a while.   I followed the Honda manual that comes with the bike and had one vid on YouTube that I liked.  I'm no mechanic, but I've have done (lets say) tires and a top end.

Also, doing the forks can be a bit messy.  It's a good idea to have some drops and cardboard around.  Rubber gloves and goggles wouldn't hurt at times.  (I'm no safety fag, but you don't want that crap in your eyes. I had an open cut on my finger that got pretty swollen that night.)

 

Parts:  I used Pivot Works PWFFK-H04-020 Fork Rebuild Kit  Which I bought on Amazon for $50.  I liked this kit because it came with all the parts you could possibly want.  I actually had extra parts when the job was over.  There's no sense in going in there if you're not going to change everything.  My bike had 70 hrs and the teflon was worn off the bushings. 

If you're thinking of doing this just to change the oil, go for it!  As I said, my ride has 70 hrs on it and that stuff came out looking pretty tired.  I used Bell Ray 5w.  I'm gonna do my '06 R which has 110 hrs for sure!

Edited by tomjv

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Hey good write up, sounds like you didnt have any real problems and got it all done, next time will go much smoother and be easier!

 

How dirty was the oil inside the chambers? Usually thats some nasty looking stuff if it hasnt ever been changed or if it has alot of hours on it since the last service.

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>Hey good write up, sounds like you didnt have any real problems and got it all done, next time will go much smoother and be easier!

 

>How dirty was the oil inside the chambers? Usually thats some nasty looking stuff if it hasnt ever been changed or if it has alot of hours on it since the last service.

 

NEXT time I'll have the wrench and seal driver and some experience, so YES it will take half the time.  Got to do the R next, which has double the hours!

The oil that came out looked pretty beat up.  It's difficult to say "how" beat up because I don't know what Honda installed in there originally.  It just didn't look like anything I've ever poured out of an oil can before.  The color was dark brown and UNuniform with lighter streaks thru it(maybe air bubbles? IDK).

TomJV
 

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