Author Topic: front suspension service  (Read 1261 times)

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Offline evinrude7

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front suspension service
« on: September 18, 2017, 06:39:54 PM »
planning to service the front suspension soon.  will i need to use new seals or will the old work if in good shape?  any other replaceable parts required during a general front suspension service? 
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Offline HondaMan

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Re: front suspension service
« Reply #1 on: September 18, 2017, 07:26:56 PM »
planning to service the front suspension soon.  will i need to use new seals or will the old work if in good shape?  any other replaceable parts required during a general front suspension service? 
If the fork seals are not leaking, all this should take is a change of the fork oil.
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Offline evinrude7

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Re: front suspension service
« Reply #2 on: September 18, 2017, 07:33:30 PM »
much obliged mr. mark. 
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Offline BomberMann650

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Re: front suspension service
« Reply #3 on: September 18, 2017, 10:24:16 PM »
If you do separate the legs.  Have new oil seals, a pair of damper rod "piston" rings, fork cap o-rings, and 4 copper crush washers handy.  All you'll need is one quart of fork oil and a measuring cup.

Should be about $80 in parts.  Worth the effort.

Offline evinrude7

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Re: front suspension service
« Reply #4 on: September 19, 2017, 05:46:15 AM »
thanks bomber
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Offline Bankerdanny

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Re: front suspension service
« Reply #5 on: September 19, 2017, 07:33:53 AM »
I understand Mark's (Hondaman) reply, but if you don't know how old your seals are I would replace them. Fork seal failure isn't a catastrophic thing and if you are in the middle of a long ride you can wait until you get home to fix it, but since you are planning a service anyway consider doing them. It adds some work to the process, but they aren't expensive and are prone to failing with no real warning.
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Offline Stev-o

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Re: front suspension service
« Reply #6 on: September 19, 2017, 08:11:16 AM »
Check your springs while you have it disassembled, if they are 40+ years old, they may be out of spec.
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Offline evinrude7

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Re: front suspension service
« Reply #7 on: September 19, 2017, 04:03:44 PM »
great tips.
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Offline Deltarider

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Re: front suspension service
« Reply #8 on: September 20, 2017, 08:03:03 AM »
I haven't had to replace one seal yet (bike is 41 years old), probably due to the harmonica rubbers. I've changed the oil once a decade and even the last time I did this, oil came out clean. I don't understand why the Owner's Manual prescribes a more frequent servicing.
« Last Edit: September 20, 2017, 08:08:31 AM by Deltarider »
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Offline Bankerdanny

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Re: front suspension service
« Reply #9 on: September 20, 2017, 10:00:02 AM »
When I changed the fluid in my bike's forks last year it came out a milky red (it has ATF in it as per the manual, I replaced the seals and refilled with fork oil)), so heavily contaminated with water. My '77 K bike in 2011 blew out the seals almost immediately after I started riding it, but then it had sat for 25 years before I bought it.

I suspect that a bike that has been continuously ridden and decently maintained can see the seals last for a long time. But if the bike has sat for extended periods the rubber can dry out and the seals fail when you start using it again.
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Offline evinrude7

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Re: front suspension service
« Reply #10 on: September 21, 2017, 05:38:31 AM »
When I changed the fluid in my bike's forks last year it came out a milky red (it has ATF in it as per the manual, I replaced the seals and refilled with fork oil)), so heavily contaminated with water. My '77 K bike in 2011 blew out the seals almost immediately after I started riding it, but then it had sat for 25 years before I bought it.

I suspect that a bike that has been continuously ridden and decently maintained can see the seals last for a long time. But if the bike has sat for extended periods the rubber can dry out and the seals fail when you start using it again.

i picked up the bike in december.  po had it outside for almost 3 years rusting away.  bought a new set of gaitors.  i figure i should at least get a look at the fork oil while i have the front tire off and plan to polish the fork bottoms. 
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Offline evinrude7

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Re: front suspension service
« Reply #11 on: September 23, 2017, 10:57:17 AM »
when reassembling the front suspension if the fender is closer to one fork than the other are the forks not even in height?  should i raise the fork that has the fender closer to it?   

edit:
the answer is yes but only a slight bit.  forks are even now.  i had to do a little tugging and pushing on the fender to straighten it after it was off and put back on. 
« Last Edit: September 23, 2017, 05:19:30 PM by evinrude7 »
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