Author Topic: Would you re-use these?  (Read 5405 times)

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Offline Heirborn

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Would you re-use these?
« on: September 11, 2006, 05:27:53 PM »
Went to pull the forks off my bike to replace the seals and once I pounded them from the triple tree this is what came out. Rust worms have been hard at work.

Unsafe to use? (Disclaimer not needed).Trying to find some for my KO is tough.
« Last Edit: September 11, 2006, 05:30:59 PM by Heirborn »
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Offline Bob Wessner

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Re: Would you re-use these?
« Reply #1 on: September 11, 2006, 05:35:04 PM »
They look pretty bad to me. If it helps any, same forks were used for K0, K1 and K2, perhaps even later. It's just that my parts list only covers thru K2.
We'll all be someone else's PO some day.

Offline jevfro

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Re: Would you re-use these?
« Reply #2 on: September 11, 2006, 05:36:48 PM »
Those fork tubes are mighty thick but,  To error on the safe side I'd probably replace them (there is quite a bit of flex in these forks to begin w/)  Others will probably have better input.

Offline puppytrax

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Re: Would you re-use these?
« Reply #3 on: September 11, 2006, 05:50:08 PM »
Trying to find some for my KO is tough.

Forks by Frank can make up whatever you need...at a rough guess (based on my CB500 quote), it'll set you back $220+...   :o ::)
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Offline Jerry Rxman Griffin aka MuthaF'er

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Re: Would you re-use these?
« Reply #4 on: September 11, 2006, 05:58:22 PM »
No way. Watch EBay. You should be able to get replacements. There are quite a few web sites which will allow you to access parts data bases. You can pull each year's K & F and compare part numbers to find compatable matches.
As of today 3/13/2012 my original owner 75 CB750F has made it through 3 wives, er EX-wives. Free at last.  ;-)

Offline MRieck

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Re: Would you re-use these?
« Reply #5 on: September 11, 2006, 06:11:37 PM »
I'd use them to beat a burglar to death....that's about it. ;) ;D
« Last Edit: September 11, 2006, 06:14:06 PM by MRieck »
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Offline miles nowhere

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Re: Would you re-use these?
« Reply #6 on: September 11, 2006, 06:13:34 PM »
No way. Watch EBay. You should be able to get replacements. There are quite a few web sites which will allow you to access parts data bases. You can pull each year's K & F and compare part numbers to find compatable matches.
yeah check ebay. I picked up a pretty much perfect set of forks for my K8 on ebay for $20 shipped.
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Offline ProTeal55

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Re: Would you re-use these?
« Reply #7 on: September 11, 2006, 06:22:12 PM »
When I removed the gators from my stock front-end my tubes looked about as bad as yours.
I would def. NOT re-use them.
As other said, just keep an eye out on Ebay and pick some up their.
Or if you have $300 buring a hole in your pocket, go get some custom made by Frank...
Joe a.k.a ProTeal55 a.k.a JoeyCocks a.k.a Maker of Friends

Offline Jonesy

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Re: Would you re-use these?
« Reply #8 on: September 11, 2006, 06:24:03 PM »
They look pretty bad to me. If it helps any, same forks were used for K0, K1 and K2, perhaps even later. It's just that my parts list only covers thru K2.

The K3 adopted a different design, without replacable bushings and used ATF for the oil.
"Every time I start thinking the world is all bad, then I start seeing people out there having a good time on motorcycles; it makes me take another look." -Steve McQueen

Offline Heirborn

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Re: Would you re-use these?
« Reply #9 on: September 11, 2006, 06:37:59 PM »
Well I guess blessings in the small things. Was going out for a run one morning and noticed that the top bridge was cracked. So found on and it is on the way. So I thought while I have it off go ahead and pull the tubes and replace the seals. Better to find out this way then at 70 rolling down the hi-way.

It is my understanding that up through the early '72 they are the same. I guess another option would be to find a complete set up (forks, caliper) from a later year model...maybe now is the time to upgrade to a front end off an F model. I also noticed the head bearings are real notchy so I will be replacing them too.
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Offline aptech77

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Re: Would you re-use these?
« Reply #10 on: September 11, 2006, 06:42:27 PM »
FUGLY!!  :-[

Offline techy5025

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Re: Would you re-use these?
« Reply #11 on: September 11, 2006, 10:19:36 PM »
I thought the K0 had a different fork seal than later ones, or is the seal different and
the fork tube the same, or am I totally screwed up.  I thought that the ads for seals
showed the K0 seal to be different. ???

Jim
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Offline Bob Wessner

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Re: Would you re-use these?
« Reply #12 on: September 12, 2006, 02:15:55 AM »
I thought the K0 had a different fork seal than later ones, or is the seal different and
the fork tube the same, or am I totally screwed up.  I thought that the ads for seals
showed the K0 seal to be different. ???

Jim

Jim,

You are correct, the seals differ. I was referring to the fork tubes themselves.
We'll all be someone else's PO some day.

Offline 750goes

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Re: Would you re-use these?
« Reply #13 on: September 12, 2006, 02:23:33 AM »
Would I re-use them ??

NAH...........

I'd paint them and put them back in....maybe put in new seals....what the hell.. :D

Offline bryanj

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Re: Would you re-use these?
« Reply #14 on: September 12, 2006, 03:56:30 AM »
No point putting seals in them the rust will rip em straight out. Also shouldnt it have gaiters not little rubber caps?
Semi Geriatric ex-Honda mechanic and MOT tester (UK version of annual inspection). Garage full of "projects" mostly 500/4 from pre 73 (no road tax in UK).

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Offline Terry in Australia

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Re: Would you re-use these?
« Reply #15 on: September 12, 2006, 04:29:24 AM »
They're buggered mate, chuck 'em and find a good used set of K0-K1 tubes. You may be able to machine K3-K8 (or F/F1/F2/F3) tubes to accept the K0-K2 bushes, I've given this a cursory glance, but haven't put my vernier on it yet, I'm waiting for El Cheapo to send me a set of K1 forks, and I know that one day before I permanently hang up my helmet, I will receive them, ha ha! ;D
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Offline Raul CB750K1

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Re: Would you re-use these?
« Reply #16 on: September 12, 2006, 05:57:24 AM »
I wouldn't dare to contradict Bryan's expertise here, but my impression is that if the "running" surface is smooth then go for it. Mine were rusted in the triple tree section but inmaculate in the "diving" area, so I just sanded out the rust, put some grease and reused them.


Raul

Offline JohnK6

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Re: Would you re-use these?
« Reply #17 on: September 12, 2006, 11:27:32 AM »
if the forks are straight even than i would trow them in the garbage dump  :-X

or brought them to a mate, and had them  new hardchromed  8)
owner of: cb750k6(76), cb750k7(78), cb750K7(79)(sold), zwolle, netherlands

Offline Heirborn

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Re: Would you re-use these?
« Reply #18 on: September 13, 2006, 08:51:11 PM »
the corrosion is from under the fork ears. Once they are re-installed the pits will be covered. The forks otherwise are fine. I would like to put boot gaitors back on so that will further help with the cosmetics. My concern is that they would be weak at the point of the corrosion.
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Offline GoatBaSS

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Re: Would you re-use these?
« Reply #19 on: September 13, 2006, 09:00:33 PM »
Thought in an artistic way of sorts, Lets build a CB from worn parts. No cleaning just nasty old parts. Not to run but some sort of monument. ?
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Offline ofreen

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Re: Would you re-use these?
« Reply #20 on: September 13, 2006, 09:06:08 PM »
You may be able to machine K3-K8 (or F/F1/F2/F3) tubes to accept the K0-K2 bushes,

Seems like Hoyt McKagen used to do this.  I've wondered a few times if anybody else does it.
Greg
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Offline Raul CB750K1

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Re: Would you re-use these?
« Reply #21 on: September 14, 2006, 12:07:48 AM »
Sandpaper and elbow grease will tell you what's the real condition. Don't be fooled by the appearance.

My CB350 forks were also rusted under the triple tree. Check the picture: They are both tubes that were rusted very similar; it's obvious which one has been sanded -a 5 minute job-. I will reuse them with complete peace of mind, either painting the hidden part previously or thoroughfully greasing them to prevent from future rust. Sand them and check the severity of the rust. If it's just surface then no problem with strenght. Furthermore, the strenght is only needed at the lowest part, where the tension is exerted. There is no side tension between the clamps.


Raul


Offline bryanj

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Re: Would you re-use these?
« Reply #22 on: September 14, 2006, 09:35:22 AM »
Raul is right, if the rust is only between the trees use them, pictures looked to me like rust was heavy by the fork slider which is why i said no way
Semi Geriatric ex-Honda mechanic and MOT tester (UK version of annual inspection). Garage full of "projects" mostly 500/4 from pre 73 (no road tax in UK).

Remember "Its always in the last place you look" COURSE IT IS YOU STOP LOOKIN THEN!

Offline techy5025

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Re: Would you re-use these?
« Reply #23 on: September 14, 2006, 10:06:34 AM »
My sandcast forks looked just like Raul's. I sanded them also and then coated them with light grease
before installing....hidden by fork ears when installed. Part near seal was fine..no rust.

Jim
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2003 CBR600F4I
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Offline MikeDeB

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Re: Would you re-use these?
« Reply #24 on: September 14, 2006, 12:38:26 PM »
As long as the seal contact surface is rust/pit free then reuse them.  I usually will take the upper part of the tube to a bench grinder with a Scotch-Brite pad mounted on it.  This will really knock the rust down.  Then, as someone else mentioned, lightly grease the uppers before installation.
Mike (Old SOHC/4 #2641)
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