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How to rebuild a "non-rebuildable" CRF150F rear shock..

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I decided to try and rebuild my sons toasted rear shock on his CRF150f..

First I have to give credit to 87aaron and wadecamp for sharing their tips on rebuilding the rear shock..I couldnt have done it without their help...Heres the link to 87 aarons thread... http://www.thumpertalk.com/forum/showthread.php?t=612308&highlight=broken+rear+shock

I took it a step further and took some pictures of the rebuild process..

Because Honda has this shock listed as "non-rebuildable" you cannot buy a rear shock seal...87aaron added a O ring but my seal was completely shot and their was'nt a drop of oil at all left in the shock...Since it was toast I thought I would try the rebuild...Didnt have nothing to lose since the shock was inoperable anyways..

I took a little gamble and bought a rear shock seal kit from Moose for the 03-07 CR85R...it also fits quite a few other bikes including the 07-09 CRF150R and more...Moose Part number 1314-0045 ..I wasnt sure if this seal kit would work but sometimes I get lucky and it was a perfect match! The OEM seals for these bikes should work too..

I used the rebuild steps on the thread by 87aaron and filled it with 5 weight fork oil...1-1/8" down from the end of the tube..added the new Moose seal and it works great now...

I took a bunch of pictures to hopefully help out other members interested in trying it theirselfs...but I'm having trouble uploading them to photobucket...I would like to do a step by step how to with the pictures...

I'll add pictures as soon as I am able....

John

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jcboyer,

Welcome to the site! I feel your rear shock information will be well received. I wish I could help you out with the pictures. Keep working at it.

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I finally have some pictures ready to upload and I'll try and go step by step on the procedure...Keep in mind that I'm no expert at rebuilding shocks and this was my first time opening up a shock so if someone with more experience wants to add some tips please feel free to do so.....I dont have a picture for every step but its relatively simple process.....

The nitrogen bladder is in a seperate compartment in the top of the shock so you wont be working with it at all...If you look about 1/4 of the way down the shock tube you will see some dimples stamped into the shock tube...this is what keeps the nitrogen bladder seperate from the lower shock....Do not attempt to fool with the nitrogen bladder.. and do not drain the nitrogen from the bladder...

Okay onto the first step...

(1) Remove the shock from the bike and clean it thoroughly..Remove all mud and crud...

Now in the pictures you will see that I wired the shock spring to keep it compressed ...YOU DO NOT HAVE TO WIRE THE STOCK SHOCK SPRING...This was my first shock rebuild and I wasnt sure what to expect with the spring but afterwards I found that it was not necessary with the stock spring... (not sure about any aftermarket spring) I did this because I didnt know if the spring was short enough... so that when I loosened the spring tension spanner nuts that it would be loose enough to get the lower shock mount off...

http://i837.photobucket.com/albums/zz295/RCWizard/crf150f%20shock%20rebuild/crfshock.jpg[/img]"]crfshock.jpg

(2) Mark the shock with a Sharpie to show where your spanner nuts are so you can get the same spring tension when you put your shock back together..(make sure the threads are nice and clean and spray a little WD40 or similar on the thread)...loosen the large top spanner locking nut and thread it all the way off..you can remove it totally off the shock....next remove the main spanner nut..Theres a lot of tension on the spring so its just doesnt spin off easily..I used a hammer a small flat piece of metal to get it off.......Once the spring is loosened unthread the main spanner nut all the way as far as possible...but it will not come completely off because of the nitrogen valve stem.....The spring should be loose now.......

http://i837.photobucket.com/albums/zz295/RCWizard/crf150f%20shock%20rebuild/crfshock1.jpg[/img]"]crfshock1.jpg

(3) Now that the spring is loose its time to remove the lower shock U shaped mount...Place a wrench on the locknut just above the U shape lower mount and use a pipe wrench or similar wrench to loosen the lower U mount...Once the U mount is off the spring and lower cup will slide off.....Now take a pair of vice grips and place them on the shaft just above the lock nut...This will not hurt anything because the shock will not compress that far with the bumpstop in place....Remove the lock nut and bumpstop....

http://i837.photobucket.com/albums/zz295/RCWizard/crf150f%20shock%20rebuild/crfshock2.jpg[/img]"]crfshock2.jpg

Heres what you should have now...

http://i837.photobucket.com/albums/zz295/RCWizard/crf150f%20shock%20rebuild/crfshock3.jpg[/img]"]crfshock3.jpg

(4) remove the lower cap that covers the seal...use a small puch or screwdriver in thetwo holes and tap it out working back and forth from one side to the other....

http://i837.photobucket.com/albums/zz295/RCWizard/crf150f%20shock%20rebuild/crfshock4.jpg[/img]"]crfshock4.jpg

(5)Time to remove the seal...Theres a circlip that holds the seal in place...If you look at the side of the shock body near the the seal you will see a small hole...Find a small pin and insert it through the hole...this will push the circlip in so you can get a very small srewdriver in there to pry it out and remove it..Not real easy..have patience..lol

http://i837.photobucket.com/albums/zz295/RCWizard/crf150f%20shock%20rebuild/crfshock5.jpg[/img]"]crfshock5.jpg

(6) Once the circlip is removed the seal/shaft can be removed...Mine was dry but you will most likely have oil in yours so have a container handy....screw the lower U joint back on the shaft just slightly(loosely) so you have something to pull with to get the seal/shaft out....Yours may pop right out but mine put up a fight.....I placed a large wrench on top of the lower U shaped mount and tapped on the wrench with a hammer...Success!

http://i837.photobucket.com/albums/zz295/RCWizard/crf150f%20shock%20rebuild/crfshock7.jpg[/img]"]crfshock7.jpg

(7) with the internals removed...completely clean the shock ...try and get the old nasty oil out making sure the shock tube is clean....next clean the shock shaft and piston..Spray some cleaner through the holes in the piston(top and bottom holes) If you look closely on top and below the piston you can see its a bunch of thin washers stacked on top of each other...My shock was dry and the washer were kinda stuck together so make sure they are clean... I'm not sure exactly what the washers do...lol.. but I think they control the oil flow through the holes in the piston head..This picture shows the seal/shaft/piston oout of the tube...

http://i837.photobucket.com/albums/zz295/RCWizard/crf150f%20shock%20rebuild/crfshock8.jpg[/img]"]crfshock8.jpg

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(8) time to put everything back together...Wadecamp said he added a O ring to his original seal (see first post for the link to his thread) but my seal was completely shot...Slide the old seal off (If your going to reuse the seal add silicone grease to the threads on the shock shaft so when you remove it you wont damage the seal) Honda does not list a seal replacement for this shock so I bought one for a CR85...Perfect fit...(See my first post for Part numbers)

http://i837.photobucket.com/albums/zz295/RCWizard/crf150f%20shock%20rebuild/crfshock9.jpg[/img]"]crfshock9.jpg

comparison.....

http://i837.photobucket.com/albums/zz295/RCWizard/crf150f%20shock%20rebuild/crfshock10.jpg[/img]"]crfshock10.jpg

When you slide the new seal in place be sure and grease the threads on the shaft with silicone grease so you dont damage the new seal and add a little shock oil to the seal itself.....

(9) once the seal is on the shaft...set it aside and fill the shock body about halfway with oil.....I was going to use 2.5 or 3 wt fork/shock oil but my local motorcycle shop only had 5 wt fork oil so that what I used...now side the shock shaft/piston into the shock tube...work it back and forth to get any air bubbles out...now with the shock piston submerged in the oil fill the tube with oil to around 1" to 1 1/8" from the end of the tube....

http://i837.photobucket.com/albums/zz295/RCWizard/crf150f%20shock%20rebuild/crfshock12.jpg[/img]"]crfshock12.jpg

(10) grease or oil the outside O ring on the seal and slide it into the shock tube...push the seal into the shock body and place the circlip in place..I had someone push the seal down into the tube while I pushed the snap ring in place...If its too tight then you may have to remove a tiny bit of oil..

http://i837.photobucket.com/albums/zz295/RCWizard/crf150f%20shock%20rebuild/crfshock14.jpg[/img]"]http://crfshock14.jpg

(11) replace the metal seal cap by tapping it back in...

http://i837.photobucket.com/albums/zz295/RCWizard/crf150f%20shock%20rebuild/crfshock15.jpg[/img]"]http://crfshock15.jpg

(12) reassemble the shock...add some blue locktite to the lower U shaped mount and tighten...

http://i837.photobucket.com/albums/zz295/RCWizard/crf150f%20shock%20rebuild/crfshock16.jpg[/img]"]http://crfshock16.jpg

(13) Finished product...

http://i837.photobucket.com/albums/zz295/RCWizard/crf150f%20shock%20rebuild/crfshock18.jpg[/img]"]http://crfshock18.jpg

Now go and ride!

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What a great way of making a used part work again, well done on the report as it is very easy to follow

Could i make 1 x suggestion that i gleamed from a 'how-to' fork seal thread?

Quote "When you slide the new seal in place be sure and grease the threads on the shaft with silicone grease so you dont damage the new seal and add a little shock oil to the seal itself...."

From the fork seal thread "When installing the new fork seal over the sharp edges of the fork bush grooves wrap a plastic bag over the fork tube and apply some grease to the bag before sliding the seal over it."

With the shaft having about an inch of threads to possibly cause damage to the new seal maybe the 'bag&grease tip' will better prevent damage than just "greasing the threads" ?:thumbsup:

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I was just looking to change the fluids in my shock too. I might just have to give it a try myself. Thanks for the post. Part numbers and very clear pictures. Great stuff. This looks like fun.

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Had your shock already been modified? Mine doesn't have a schrader valve on top like your does. Also, how much air pressure did you have in the shock? Is the entire shock body full of oil, or is there supposed to be some compressed air in there as well? I know that on shocks that have air bladders, you have to run about 160psi.

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As far as I know its the stock shock...I bought this bike for my son and it was completely stock and I'm almost positive that its the stock shock...Its a 2005 model so maybe they changed a few things inside the shock over the years....I know there is pressure in the bladder (nitrogen) but I'm unsure how much.... I filled the shock as full as possible with oil and tried to get all the air out but its difficult to get every bit of air out....It seems to work well while sitting on it and working the suspension up and down but he hasnt rode it yet because I'm rebuilding the motor right now....

Like I said I'm not an expert on shock rebuilding and I would only rebuild the shock as a last ditch effort to get some life out of a otherwise useless shock..In other words, I wouldnt open up the shock just to change oil in it..I think you know what I mean....

If your shock doesnt have the schrader valve than it may be different internally and I cant reccomend this rebuild since I dont know if it has a bladder inside to worry about..I would assume it doesnt have a bladder but I dont know for sure....Maybe someone else would know for sure..

btw.....The plastic bag over the threads to protect the seal is a great idea!

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My stock shock did not have a schrader valve on top, but after I had it rebuilt by Hlebo Bros suspension it did have a schrader valve. Hmmmmmmmm.

Gabechroust,

Thank you. I was wondering about that. I thought I was crazy. The funny thing is, I have a Hlebo's shock too so I have the valve too. hehe. Lucky us.

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Has anyone rebuilt a non-blown shock? I think Hlebo starts by carfully drilling the top of the shock where he later places the shrader valve. This would release the nitrogen that presurises the shock. I have rebuilt a couple of big bike shocks and you have to release all the nitrogen prior to disssasembly. If you don't do this the shock shaft can become a projectile when you remove the circlip that holds the seal in.

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i did the shock on my 250 the other day, i put 165 lbs of nitrogen in the bladder..

p.s. do not use air!!!!

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When I had the shock dissasembled, I looked inside the tube and it looked like a concave metal disk just above the dimples in the tube...The dimples hold the concave metal disk so it cannot come out of the shock...I'm assuming the bladder is just above the disk.....

Other shocks may be different and I wouldnt want someone getting injured trying to rebuild the shock.... so I wouldnt reccomend this unless your shock is the same design as the one in the pictures...

There has to be someone who knows more about shock rebuilding that could give us some insight on this..........the bike is a 2005 model and maybe the newer models have a different shock...

Edited by jcboyer

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JC have you ridden on your rebuilt shock yet? Did you recharge the nitrogen?

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I'm currently rebuilding the motor so we havent had a chance to ride it yet...I didnt have the nitrogen recharged...I never released the pressure when I rebuilt the shock.....I'm unsure of the pressure thats currently in the shock because my guage only goes up to 90 psi and it went past 90...

I was just wondering if..... when Hlebro rebuilds a shock if he puts a schrader valve in for nitrogen/bladder or is it there just to help aid in refilling the shock with oil and to release any air trapped in the shock??? Its difficult to get all the air out out of the shock..

Does the stock shock you guys have (the ones without the Schrader valve) have dimples stamped into the shock body?? just wondering if they even have a pressure bladder in them..

This is my sons first bike and the stock shock was like a Pogo stick..Just bounced up and down with no resistance..It was evident there was little if any oil left in it....so I had nothing to loose by trying a rebuild and I figured since he is new to bikes that hes only going to be doing easy trail riding for a while till he gets used to it than this shock should work fine for him...I will update you once we get it running but while sitting on the bike and working the suspension it a made a huge improvement...

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Would this work for the crf230f rear shock as well? Would it be the same seal kit and if not does anyone know if there is one that would work?

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