spacers on forks?? Fork rebuild.

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Stratkat
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spacers on forks?? Fork rebuild.

Postby Stratkat » Fri Mar 08, 2013 3:18 pm

dudes i am rebuilding my forks. i took em off and apart, and noticed the spacers are not symmetrical at all!
you are seeing them as they were disassembled. the springs are the same length, the aluminium spacers are the same length,
and if you stack the spacers for the left fork together and the right fork, there is about a 1/16" difference.
whats the deal here?
ive owned the bike since it was new and the forks have never been apart, any ideas on whats going on?

http://s447.beta.photobucket.com/user/b ... sort=3&o=0
Last edited by Stratkat on Fri Mar 08, 2013 3:49 pm, edited 2 times in total.

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weeksy
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Re: spacers on forks?? Fork rebuild.

Postby weeksy » Fri Mar 08, 2013 3:19 pm

linky no worky
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Stratkat
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Re: spacers on forks?? Fork rebuild.

Postby Stratkat » Fri Mar 08, 2013 3:29 pm


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weeksy
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Re: spacers on forks?? Fork rebuild.

Postby weeksy » Fri Mar 08, 2013 3:31 pm

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Stratkat
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Re: spacers on forks?? Fork rebuild.

Postby Stratkat » Fri Mar 08, 2013 3:33 pm

try this

http://s447.beta.photobucket.com/user/b ... sort=3&o=0

to make it more confusing the KTM parts fiche shows 3 spacers but lists 4 part numbers!

orpheus
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Re: spacers on forks?? Fork rebuild.

Postby orpheus » Fri Mar 08, 2013 5:38 pm

I had the same on mine 2 at the bottom 1 at the top and reverse on the other leg. I was going to put them back as was but ended up going with 2 at the top and 1 at the bottom. I really couldn't see what difference it would make as your preloading the spring the same amount which ever way around you have them. I figured with the preload adjusters at the top it was probably better to have the 2 discs at that end just in case things need to spin around.

Also the fiche has them this way around >

http://shop.jimaimracing.co.uk/acatalog/fiche_front_fork_disassembled_990_superduke_07-09.html

Be nice to get an answer from someone who knows though...

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Stratkat
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Re: spacers on forks?? Fork rebuild.

Postby Stratkat » Fri Mar 08, 2013 6:41 pm

orpheus wrote:I had the same on mine 2 at the bottom 1 at the top and reverse on the other leg. I was going to put them back as was but ended up going with 2 at the top and 1 at the bottom. I really couldn't see what difference it would make as your preloading the spring the same amount which ever way around you have them. I figured with the preload adjusters at the top it was probably better to have the 2 discs at that end just in case things need to spin around.

Also the fiche has them this way around >

http://shop.jimaimracing.co.uk/acatalog/fiche_front_fork_disassembled_990_superduke_07-09.html

Be nice to get an answer from someone who knows though...


yeah but look close there are 2 spacers on one leg and 4 on the other! they equal about the same for each leg, but what the hell?
is it because different techs build them individually, then when assembling the bikes they just grab them in what ever order they happen to have?

orpheus
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Re: spacers on forks?? Fork rebuild.

Postby orpheus » Fri Mar 08, 2013 10:02 pm

If you check the fiche there are 3 different thickness of shim - item 6 has 1.5, 2.5 and 5 listed. So maybe they are just used to get an equal spring height or total length. Didnt notice that before so maybe the order doesn't matter but the spring height does.

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Willh
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Re: spacers on forks?? Fork rebuild.

Postby Willh » Fri Mar 08, 2013 11:15 pm

My 640 had around 3mm difference in preload shims side to side when I opened them up :?

High flow head had grinder ding on one of the valve seats, valve spring colour codes were mixed, one of each per side,( might not be a big deal).

Assumed it to be a Friday afternoon/Monday morning build...
2008 Superduke
850 Commando engined '68 P11 project

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Stratkat
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Re: spacers on forks?? Fork rebuild.

Postby Stratkat » Fri Mar 08, 2013 11:33 pm

ill just put it back together, it didnt seem to affect it badly!
just changed out the headset bearings and got that stuff reassembled, ill finish the forks tomorrow.

ibbob50
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Re: spacers on forks?? Fork rebuild.

Postby ibbob50 » Wed Jan 15, 2014 11:48 pm

Old thread, I know.

Just want to put up more information on the subject.

I just rebuilt my forks. One leg had two preload spacers, the other had just one. I'm speaking of the white plastic rings under the fork cap AKA #6 on the parts fiche.

I was certain I hadn't lost any spacers on disassembly, so I'm glad to hear others are discovering the same thing with their forks.

I plan to reassemble with the same (odd) preload spacer set-up.

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Re: spacers on forks?? Fork rebuild.

Postby Stratkat » Thu Jan 16, 2014 7:49 pm

i just put them back they way they came out, i may have switched the order, (some were on the bottom of the spring!), and its just fine.
i think (though i didnt check) the springs are slightly diff lengths and they stack the spacers to get them the same, cant think or any other reason...

slfishf1
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Re: spacers on forks?? Fork rebuild.

Postby slfishf1 » Fri Oct 26, 2018 12:48 am

The parts fiche in one of the previous posts is different that what's shown in the WP rebuild manual. The parts fiches shows the spacer placed under the spring. The rebuild manual I downloaded here: http://ktm950.info/library/assets/pdfs/ ... 2005-E.pdf shows on page 4.3 for the Superduke (manual is for years 05-08, mine is an 08) the spacer on top of the spring. Which is actually correct? Mine had the spacer on the bottom when I disassembled. Used bike so curious whether the previous owner was in the forks and put them together wrong or the official manual in incorrect.

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SDNerd
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Re: spacers on forks?? Fork rebuild.

Postby SDNerd » Fri Oct 26, 2018 3:30 pm

It's just a spacer - it doesn't move (or shouldn't), so it really doesn't matter that much. The only upside of having them both top and bottom, is that the plastic spacer gives a slight bit of cushion to the springs' ends - versus metal-to-metal contact.

My forks too had an oddball combination of spacers in them (and asymmetric). I don't know if KTM had a large length tolerance on their springs - or what - to catalog a range of spacers to get the preload where they wanted it. It could also have been that this was done late in the assembly process at WP - perhaps they added spacers until the they got the desired stack height then closed them up. My suspension guy and I had a laugh about this. Would have made sense if there were no preload adjusters...


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