How to rebuild your front forks

[PedroTQ]

Gooday to All,

I have stripped my 1988 front forks down to wash out the black sludge within.

But I now have a problem

I followed the instructions as I went along, then to my surprise one fork innards has an extra part and retaining clip compared to the other. I did not make a mention to which went with what on disassembly, I just presumed they would be both the same. (silly me).

Someone has been there before as the adjustment caps have been modified to be useless, so just maybe they also left out or lost the part concerning me

Can anyone help me ???? .... Please, Left or Right fork

[MasterDaniel904]

Hey all! I decided to do my GL1500 forks and I decided to order the fork tool from Parzilla for about $170. Didn't inspect it closely and unpacked it when I got to needing it. Turns out that Honda doesn't include the pinch bolt (step 60)! I called Partzilla and they called Honda and confirmed it. So it was off to the hardware store for an M8-1.25 bolt and washer. Plan ahead, I didn't and it's delaying the next ride!

[WingAdmin]

Hey all! I decided to do my GL1500 forks and I decided to order the fork tool from Parzilla for about $170. Didn't inspect it closely and unpacked it when I got to needing it. Turns out that Honda doesn't include the pinch bolt (step 60)! I called Partzilla and they called Honda and confirmed it. So it was off to the hardware store for an M8-1.25 bolt and washer. Plan ahead, I didn't and it's delaying the next ride!

You're 100% right, I should have mentioned that...but to tell you the truth, I didn't remember it until you just now mentioned it!

[MasterDaniel904]

Okay, having removed the springs, and the first oil seal, I am now faced with an oil seal that will not move. Step 75. I have tried gently, vigorously, and then a heat gun. That sucker is just not moving a millimeter. If I pull hard, the whole piston jams and has to be beaten (covered with a 2x4) to release. I'm wide open to suggestions. That $375 labor charge at the local Honda is beginning to look like a bargain!

[WingAdmin]

Okay, having removed the springs, and the first oil seal, I am now faced with an oil seal that will not move. Step 75. I have tried gently, vigorously, and then a heat gun. That sucker is just not moving a millimeter. If I pull hard, the whole piston jams and has to be beaten (covered with a 2x4) to release. I'm wide open to suggestions. That $375 labor charge at the local Honda is beginning to look like a bargain!

I know it's obvious, but you did remove the locking ring, right?

[MasterDaniel904]

Okay, having removed the springs, and the first oil seal, I am now faced with an oil seal that will not move. Step 75. I have tried gently, vigorously, and then a heat gun. That sucker is just not moving a millimeter. If I pull hard, the whole piston jams and has to be beaten (covered with a 2x4) to release. I'm wide open to suggestions. That $375 labor charge at the local Honda is beginning to look like a bargain!

I know it's obvious, but you did remove the locking ring, right?

(chuckle) I remembered after trying to pull it out a couple of times! I got it right the first fork! But removing the locking ring hasn't made a difference. This thing is just not moving. It's like the guide bushing is jamming up into the backup ring instead of forcing the backup ring against the oil seal. I don't know what kind of polymer that seal is made of, but it wont cut, bend, melt (tried to cut it with a soldering iron), anything. So far I've avoided scratching the piston, but if I can't get this ring out, well, I can't afford an entire fork!

[WingAdmin]

If it is in fact jamming in the slot where the locking ring normally lives, I would gently lift the fork up to the point where it jams, then gently pry it away from the inner wall, to prevent it from hanging up in that slot, while applying gentle pressure to move it outward. Without seeing it in front of me, it's tough to tell what exactly is hanging up.

[MasterDaniel904]

Okay, problem solved. I took the fork to a machinist and he and I pondered on the problem for almost an hour. First he used a seal puller to remove the seal and washer, which proved there was nothing unusual preventing its removal. I am definitely getting one of those tools! We still could not remove the fork tube. He finally chucked the fork tube into his lathe, and while I pulled on the lower tube, he struck the top of the lower tube with a nylon shot hammer a few times and we popped the lower tube off. What was happening was there was so much wear on the slide bushing, it was actually sliding UNDER the guide bushing and creating a wedge instead of pushing against the guide bushing to force off the washer and seal. We protected the upper tube with a rag and careful examination showed no damage from the process aside from a few scratches at the top of the fork tube from the lathe chuck which should not effect its use.

Time to clean the parts thoroughly and reassemble!

[Molsberg]

Well, I want to thank everyone for the wonderful advice and information in this article but I find myself with an issue on my 89 1500 Aspy. Have pulled the forks out and cleaned them up and realized that in the factory manual and some of the diagrams in here that it reflects 2 springs (an A and a B) in each tube. Well, mine only has one spring and the tighter wound portion is at the top contrary to what I read should be at the bottom. I appear to be missing the B sprint (short one) and the spacer. Since I purchased it used, I don't know whether it was changed purposely or it was made that way. So, my questions are... should there be a second spring; qne should the tighter wound spring be on the bottom as opposed to being on top?
Thanks for all the help!

[WingAdmin]

Well, I want to thank everyone for the wonderful advice and information in this article but I find myself with an issue on my 89 1500 Aspy. Have pulled the forks out and cleaned them up and realized that in the factory manual and some of the diagrams in here that it reflects 2 springs (an A and a B) in each tube. Well, mine only has one spring and the tighter wound portion is at the top contrary to what I read should be at the bottom. I appear to be missing the B sprint (short one) and the spacer. Since I purchased it used, I don't know whether it was changed purposely or it was made that way. So, my questions are... should there be a second spring; qne should the tighter wound spring be on the bottom as opposed to being on top?
Thanks for all the help!

It sounds like you may already have a progressive spring in your forks; and it doesn't matter all that much whether the tighter part is at the top or the bottom; for most people you will likely not be able to tell the difference!

[Molsberg]

Thanks WingAdmin. I went ahead and put it back together with the tighter wound end down and when the fork is extended, only about an inch and a half is showing at the top of the tube. Guess I should have measured the length but this was my first time doing this and I incorrectly identified it as the A spring when it would have been the B spring.. but your statement makes sense since the one spring covers the entire tube. I didn't experience the large amount of force I would have expected when removing the cap though for a progressive spring and I have no clue how long they have been in there. Maybe time for a new set even though she only has 65000 miles on her. Thanks again! Mark

[GlimWas]

I have installed Progressive springs (Wilbers) today and with help of your DIY it was like a walk in the park.
I must say that i have removed the bolts on top of the forks manually and had no difficulty what so ever, the force was easily managaeble for me. It helps that i am a big fellow of course...... As long you have the fork spanned in a workmate or something like that it isn't difficult to manage the force. Thanks for the DIY

[hazelwoodgarage]

The spring compressor tool on cycle max is now at 182 dollars, I just rebuilt one of my forks on my 94 interstate that was really leaking, The oil ran down on the brake pads so the brakes weren't very good either, I put new brake pads in too as one side was bad, I made my own tool for compressing the spring , it took me about an hour and a half to make, it didn't look too pretty but it works, I can post a photo.

[millerized]

Fork tube drain bolts....if they strip or won't come out...don't fret.
I mean you can freak out...it's what "I" just did when the first one stripped out. The 6mm socket hole wasn't perfect from the last guy to take it out...I just made it worse when it wouldn't even budge with a 18" breaker bar.
My fix, and it'll be Tuesday before I'm 100% sure it'll work, but...here it goes:

Find a drill that 'just' fits into the socket part of the screw and drill down until it feels 'different'. About 1/4" or so should be more than enough.
Take a punch that will fit into that hole, and give it a whack. If the head doesn't separate from the threaded portion, drill down a little more. Whack it again. The head will separate from the body of the bolt without damage to anything inside the fork body. When you pull the fork apart to clean/check/rebuild it, the bolt portion will unscrew nicely from the bottom of the inner fork guts.
You can order new bolts and wait a week or so, or find an 8x1.25MM bolt about 18mm long with a 6mm tall socket head and about 13mm wide. This will fit nicely into the space. McMaster Carr part #91290A422 is a bit taller, but the crown will 'just' clear the axle. Might take a tiny bit of filing at most.
Yeah...stripped out both, snapped the heads off, bought new bolts and off we go.

[JAcossey]

I was wondering if you could break that spring tool down and make some pics for me. I am a tool maker and I think I can duplicate it. That will save me that 150$ And on a toolmakers salary that is a bigun!! What prompted you to rebuild your forks? We're they like mine having play in them? Just curious. Is there a way to tell if that play is truly coming from the forks and not the bearings up top in the triple tree?

[MasterDaniel904]

For me, like some of the other chaps here, it was obvious fork oil leakage at the seal that prompted the repair. Which means it should have been done sooner!

[jim34481]

I just completed rebuilding my forks and installing progressive springs in my 97 gl 1500 se using this DIY article. It is absolutely a great tutorial step by step procedure that anybody should be able to use. Thank you wingadmin for sharing your knowledge and common sense. You have a talented ability to make a complex task relatively easy in the procedures you have developed.
Thanks
Jim

[jimbo73]

Just took my forks out of my 90 and have a question. your instructions say the tube spring is under pressure. i haven't disassembled them but if i turn them upside down the bottom casing moves about 5-6 inches and back if i turn it back upright. i'm thinking the springs are shot or broke and will they be under pressure when i take them apart?

[GlimWas]

In my experience, the pressure is manageable. just put your weight on the ratchet and take the hex bolt off. Be sure to fix the fork in a workmate or something like that so you can put your weight on it safely. I had no problems this way and my springs were definitely not shot.

[WingAdmin]

As you saw on my original posting, the spring on my GL1500 was extended considerably far out of the shock:



There was a good 80 or 90 pounds of pressure required to push that down far enough to get the cap screwed into place. The cap has extremely fine threads, and 80 or 90 pounds is more than enough to rip out a couple of these threads if you aren't careful: