Fork Spacer/Washer Question

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For those of you who've stalled aftermarket springs (sonic 1.2) when you cut your PVC pipe, what length did you use, and did you use the factory thin washer on top of the PVC, or allow the PVC to slip up into the cap? Will it hurt anything if the spacer is up inside the cap? I was wondering if being "trapped" by the center of the cap would cause any binding? With the stock set up the spacer sits directly on the edge of the for cap. I tried using the set up recommended by sonic (washer between spring and PVC spacer, then oem washer on top of spacer) and I am getting a lot of mechanical noise, which I suspect is the washer slipping back and forth on the spacer and coming in contact with the sidewalls of the fork tube.
Comments or suggestion?
 

ChucksKLRST

Team Colorado
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For those of you who've stalled aftermarket springs (sonic 1.2) when you cut your PVC pipe, what length did you use, and did you use the factory thin washer on top of the PVC, or allow the PVC to slip up into the cap? Will it hurt anything if the spacer is up inside the cap? I was wondering if being "trapped" by the center of the cap would cause any binding? With the stock set up the spacer sits directly on the edge of the for cap. I tried using the set up recommended by sonic (washer between spring and PVC spacer, then oem washer on top of spacer) and I am getting a lot of mechanical noise, which I suspect is the washer slipping back and forth on the spacer and coming in contact with the sidewalls of the fork tube.
Comments or suggestion?
I cut my spacers to the Sonic springs and spacers were the same total length as the Honda springs and spacers. I also went to the hardware store and bought 4 washers with a hole large enough to slip over the anti dive rod. One washer between the spring and space and the other washer on top of the spacer and the fork cap. See pictures. Rode this set up for almost 80k miles before I traded it in with a 130k miles for my FJR.

Hope this helps. Edit: Pictures are in reverse order.
 

dduelin

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I don't have Sonics but I made up PVC spacers for additional preload on stock springs. My spacers bear directly against the fork cap- no washers on the top of the spacers. If you use PVC pipe with 1.5" OD they are almost an interference fit in the steel fork tubes - no rattling. If the spacers and washers are much smaller in OD than 1.5" they may be tapping on the inside of the tube when the forks are working.
 

T_C

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I installed the Sonic Springs as per the Sonic suggestions for washers. No noticeable noise on my ride. Or maybe the ear plugs I wear do a really good job? No, I am pretty sure there is no noticeable noise for the Sonic Springs with PVC spacer and the one OEM and one Soic provided washer.
 

Reginald

cyclepoke
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140mm spacers. Spring, washer, spacer, cap, in that order
+1
Definitely use the steel factory washer between the push rod and spacers. I used the Race Tech springs, the 3mm washer spacers that come with those springs are aluminum. I should have cut my PVC spacer 3 to 6 mm longer. I had to use three 3mm washer spacers to get the preload right. I disassembled, added a washer spacer, and reassembled three times to get the preload and sag right. There was no washer or washer spacer at the top of the original steel spacer and between the fork cap, so when I put in the PVC spacer, I didn't add one. My PVC spacer rests against the fork cap.
 
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I had to use three 3mm washer spacers to get the preload right. I disassembled, added a washer spacer, and reassembled three times to get the preload and sag right.
Don't know if this would apply to the 1300 like it would to the 1100, where one fork is just a plain spring with no rod in the center, but I was wondering...

given that externally adjustable fork caps have been around for quite a few years, has anybody tried to swap one from another bike onto the ST ??? I know there's a lot of different diameter tubes to start with, but for a given fork tube diameter what's the chance the cap threads would be the same pitch?? I'm guessing with all the bent forks out there in junkyards there has to be a supply of adjustable caps that could be purchased cheaply. Anybody ever looked into this??
 

CruSTy

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I don't have Sonics but I made up PVC spacers for additional preload on stock springs. My spacers bear directly against the fork cap- no washers on the top of the spacers. If you use PVC pipe with 1.5" OD they are almost an interference fit in the steel fork tubes - no rattling. If the spacers and washers are much smaller in OD than 1.5" they may be tapping on the inside of the tube when the forks are working.
Dave,

When you installed the 1.5" O.D. PVC spacers what did you use for washers between the spacer and spring? I'm getting ready to do install the 1.5" ones as well. The washers that come with the Sonics are too small O.D. to rest on the spacer correctly. I looked for standard washers at the local hardware stores but didn't find anything that fit right either. I'm thinking the stock ones might work but won't know until I get them out.
 

dduelin

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Dave,

When you installed the 1.5" O.D. PVC spacers what did you use for washers between the spacer and spring? I'm getting ready to do install the 1.5" ones as well. The washers that come with the Sonics are too small O.D. to rest on the spacer correctly. I looked for standard washers at the local hardware stores but didn't find anything that fit right either. I'm thinking the stock ones might work but won't know until I get them out.
I use the stock ones.
 

CruSTy

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; said:
No washer between spring and pvc. Washer at top of pvc and bottom of spring.
not trying to be a butt head but I believe this is mis-information. A washer needs to go between the bottom of the spacer and the top of the spring to allow the spring to sit square. Without that washer the spring can sit off center in the spacer causing it to distort. It may even cause the spring to rub the side of the fork tube.
 
Last edited:
Joined
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not trying to be a butt head but I believe this is mis-information. A washer needs to go between the bottom of the spacer and the top of the spring to allow the spring to sit square. Without that washer the spring can sit off center in the spacer causing it to distort. It may even cause the spring to rub the side of the fork tube.
+1

parts fiche shows washer between spring and spacer
 
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