Question: '88 forks with spacer (lowering) mod

[Shuriken]

Got some '88 front forks from eBay. Seller said the following:

"Came out of a running bike with about 11k miles.
Straight and pretty clean on the sliders..very little rusting.
Seals were replaced a season befor being removed.
Bike was lowered 1/2 inch by putting in different space.
Fluid was changed at the time.

On Sep-17-08 at 05:06:55 PDT, seller added the following information:
They are the smaller forks...from a 1988...all my parts or from an 88..."

So what would he have done? To do this mod, do you remove the aluminum piece that attaches to the end of the damper rod via the allen screw and replace it with a different spacer? A spacer from what? What kind of spacer?

 

[vmax1125]

sounds like they were lowered internally using a spacer under the damper rod. they can be made from steel , aluminum,delrin and pvc i made my 2" spacers from sch 80 pvc works great on late model 43mm forks.
Chris

 

[maleko89]

The lower block is just a tube that fits on the damper rod...it goes between that and the rebound spring. What it does is prevent the fork tube from fully extending. Take a look at the pic, it might help. Think of the top spring under damper rod head as the lowering block. They are probably PVC in the forks you bought.

You will need to separate the fork tubes from the sliders to remove the blocks. It's also possible he put 20 weight on there as that is what a lot of suspension experts recommend. That would make for a rough ride. 15 weight would be better IMHO.

 

[vmax1125]

Mark,
i found out after dismantling my forks that you do not have to seperate the tubes to add or remove lowering blocks just remove the damper bolt then pop out the main spring and spacer with a telescopic magnet slide it down the tube to the damper rod then slowly pull it up . once you have that out drop it in again to get the top out spring .
if you have a pvc spacer in the tubes you will need to pull them ouy with some other means a long grab tool works. you only need to pull the sliders off to install new seals i found out the hard way but its fairly easy reguardless.
Chris :eusa_dance:

 

[maleko89]

Chris, good to know! Thanks!

 

[Shuriken]

Should I keep them as they are and run 'em lowered, or inspect?

 

[gleno]

Should I keep them as they are and run 'em lowered, or inspect?

Well, unless you trust the vendor with your life, pull it down and inspect.

You can also use another spring instead of the spacer on the damper rod which, makes the magnet retrieval idea a real beauty.

 

[Shuriken]

sounds like they were lowered internally using a spacer under the damper rod. they can be made from steel , aluminum,delrin and pvc i made my 2" spacers from sch 80 pvc works great on late model 43mm forks.
Chris

Old topic... just getting back to this project...

Chris, when you say "works great," what do you mean? What are the benefits of internal lowering?

 

[Shuriken]

Had a heck of a time with the forks. One seemed to be plugged before I finally got the oil out of it.

So when you release the pressure on the large cap on top, out pops a metal tube maybe 5 inches long. That and another smaller tube (probably the spacer that was added). So the stock configuration does not have a 2nd spacer, right? And this added spacer just serves to compress the spring further, which should shorten the fork by a small amount and which should make for a stiffer fork?

 

[one2dmax]

Sounds like someone jacked up the original spacers. The original spacer is more like 8-10" long (can't remember the length right now). They probably added the second spacer when the first one wasn't but right. You only need one spacer and set to 1" preload. DO NOT cut the spacer to lower the bike as this isn't the right method and EXTREMELY unsafe.

Sean

 

[[email protected]]

Had a heck of a time with the forks. One seemed to be plugged before I finally got the oil out of it.

So when you release the pressure on the large cap on top, out pops a metal tube maybe 5 inches long. That and another smaller tube (probably the spacer that was added). So the stock configuration does not have a 2nd spacer, right? And this added spacer just serves to compress the spring further, which should shorten the fork by a small amount and which should make for a stiffer fork?

The spacers that sit on top of the spring will stiffen the ride but they WILL NOT shorten the fork by any means. The only way to "shorten" or lower the fork is to put a spacer on the damping rod. This increases the overlap of the fork slider into the fork tube and thus shortens or lowers the forks.

 

[Shuriken]

Sounds like someone jacked up the original spacers. The original spacer is more like 8-10" long (can't remember the length right now). They probably added the second spacer when the first one wasn't but right. You only need one spacer and set to 1" preload. DO NOT cut the spacer to lower the bike as this isn't the right method and EXTREMELY unsafe.

Sean

Thanks for the replies, guys.

So what you are saying is that I should take apart my OEM 85 forks and see what's going on with the OEM spacer which sits on top of the spring near the top cap. Swap those unmolested, stock-length spacer tubes in because having 2 spacer tubes is wrong and unsafe...

I have the worst luck with front forks. Bought some from Huberj a long time ago and they appeared to have pitted fork tubes so I sent them back. Now got these crappers and Jeff said his were fine and I believe Jeff.... :bang head:

I'll get the top spacer tubes correct before riding the bike and when I get my new fork seals, I'll swap back on the 85 forks again, probably.

 

[Shuriken]

The spacers that sit on top of the spring will stiffen the ride but they WILL NOT shorten the fork by any means. The only way to "shorten" or lower the fork is to put a spacer on the damping rod. This increases the overlap of the fork slider into the fork tube and thus shortens or lowers the forks.

OR... I could just get progressive springs and use stock spacers on top of the spring then, right?

So one more time for the slow person here.... the damping rod already has the stock spacer thing on the bottom of it that the allen screw attaches into, right? So is that the spacer we are talking about? Someone shortens or lengthens it? You would cut off a half inch to increase overlap of the fork slider into the fork tube, right? Or you would replace the stock spacer with a shorter one?

 

[[email protected]]

When you take the cap off the top of the forks and you see the spacer immediately under the cap, that is the preload spacer. This spacer will preload your fork spring. Under the spacer you will find a flat washer and then the fork spring. The longer the spacer, the more force applied to the fork spring, the harder it is to compress the forks. Therefore, you can firm up the front fork springs buy just installing a longer spacer.

The spacer can be made out of PVC or steel pipe. Doesn't matter. Having two spacers is not necessiarily unsafe. What is unsafe is putting in a very short spacer that does not preload you spring in an attempt to lower your forks. It will not lower your fork and will be dangerous to ride. If you need spacers just spend $5 at home depot and buy a stick of PVC conduit and cut what you want.

To lower the forks internally further disassembly is required. Once the spacer, washer, and spring are out the damper rod needs removed. That is retained by the bolt in the bottom of the fork leg. Remove the damper rod, add a spacer (again PVC is fine) the amount you want to lower and reassemble. This spacer limits the amount that the fork tube can extend up out of the leg.

 

[Shuriken]

When you take the cap off the top of the forks and you see the spacer immediately under the cap, that is the preload spacer. This spacer will preload your fork spring. Under the spacer you will find a flat washer and then the fork spring. The longer the spacer, the more force applied to the fork spring, the harder it is to compress the forks. Therefore, you can firm up the front fork springs buy just installing a longer spacer.

The spacer can be made out of PVC or steel pipe. Doesn't matter. Having two spacers is not necessiarily unsafe. What is unsafe is putting in a very short spacer that does not preload you spring in an attempt to lower your forks. It will not lower your fork and will be dangerous to ride. If you need spacers just spend $5 at home depot and buy a stick of PVC conduit and cut what you want.

To lower the forks internally further disassembly is required. Once the spacer, washer, and spring are out the damper rod needs removed. That is retained by the bolt in the bottom of the fork leg. Remove the damper rod, add a spacer (again PVC is fine) the amount you want to lower and reassemble. This spacer limits the amount that the fork tube can extend up out of the leg.

Thanks for the explanation. That helps. I don't mind a stiffer spring but it starts to become extremely difficult to screw down the cap without tearing up the threads or extremely difficult overall just to reassemble, even with the load off of the forks.

 

[Icepick]

let me ask this, on the damper rod i have a small 1"? spring, and a small plastic tube, does it matter which one goes on the damper rod first, the spring or the tube?

 

[Redbone]

Check out video on post #29 in Sean's Morley Muscle how-to Videos.

 

[Icepick]

5 min.? hell it took me 2 days!!!

 

[one2dmax]

LOL, I haven't done a set in a month or two and was rushed last night. i think it took me longer since I was in a hurry then it would have it just done the work at the normal pace. It took a little over an hour to R&R the seals give or take a little bit.

Sean