Fork oil changing

john robert bould · Jul 9, 2013

Over the last 4 years the issues with forks as become quite an issue with me, since developing the damper system i have had hundreds os emails regarding fork action.
The general issue is after the dampers are fitted and the forks don't react like the owner had hoped for.
I have concluded the sliders now 40 years old have some wear in them, not really a leap from the bath conclusion is it :lol:

Forks must be one of the most over-looked on a bike.
yearly oil change's are a real MUST!
Why;;;; well as you are enjoying a nice weekend run about, deep inside your forks the springs are nicely grinding them selves away, when a spring becomes compressed it "snakes" up and this push's the snakes butt and belly against the inner stanchion wall, [new indian /chineese] stanchions are poorly finnished inside, but thats another issue. I have compressed a spring onto a threaded rod, the snaking is quite strong, it's very tight when pushed/pulled in a tube.
Anyway after many miles the spring get's a wear flat on the sides, this metal as fallen into the fork fluid, its micro shards of spring steel.
this fine grinding compound mixed with water/oil now gets between the lower iron bush and the alloy slider wall, and frets away the metals.
Over time the slider becomes "barrell" shaped, the results are quite deep after time. How many of you guys found the new bush kit feels great at the top then suddenly goe's slack when pushed half way in? then tight again at the bottom.

A few purchasers of the dampers find the new units have not restored the forks to "as new" , they never will!

So just think on...change the grinding sludge ! Better before laying up for the winter as water will rust the dampers .

It's out of sight,out of mind....put it on you chore list!!!

concours · Jul 9, 2013

+1 Often overlooked maintenance, especially by "casual" motorcycle owners. My all-time favorite fork juice was Kal-Gard Smooth Stroke oil with moly... "Like buttah baby"

john robert bould · Jul 9, 2013

Spread the word! Maintenance is what i grew up with, got my C&G in maintenance studies....what sae grade is your Kal-gard?
Is it still available in the good ol US of A?

concours said:
+1 Often overlooked maintenance, especially by "casual" motorcycle owners. My all-time favorite fork juice was Kal-Gard Smooth Stroke oil with moly... "Like buttah baby"

concours · Jul 9, 2013

john robert bould said:
Spread the word! Maintenance is what i grew up with, got my C&G in maintenance studies....what sae grade is your Kal-gard?
Is it still available in the good ol US of A?

concours said:

+1 Often overlooked maintenance, especially by "casual" motorcycle owners. My all-time favorite fork juice was Kal-Gard Smooth Stroke oil with moly... "Like buttah baby"

Click to expand...

No longer available, used to be 5W on up through 30W. I recently scored a couple ancient qts. from a craigslist ad 3000 miles away in California. :mrgreen:

mike996 · Jul 9, 2013

I seem to recall that I think I may remember that possibly I might have changed the fork oil once but I'm not sure...

OK, seriously, I did the Fauth fork mod a few years back and was quite happy with it but I haven't changed the oil since then - sort of using the logic that since none of it is on the ground (no leaks/seeps) it must all still be in there. But, of course, that doesn't account for the fact that it may be doing more harm than good without regular changes as you pointed out. FWIW, Fauth recommends ATF as the fluid with that mod.

In any case, your post has "shamed" me into changing it! Thanks.

john robert bould · Jul 9, 2013

Excellent,
Do me a favor. when you have the oil from your forks ,hang a magnet into the jar, swill it about and hang it up tp drip dry, then wipe the magnet with a clean white paper towel ...report if anything is found please.It should be a faint gray colour? hopefully Not!!

mike996 said:
I seem to recall that I think I may remember that possibly I might have changed the fork oil once but I'm not sure...

OK, seriously, I did the Fauth fork mod a few years back and was quite happy with it but I haven't changed the oil since then - sort of using the logic that since none of it is on the ground (no leaks/seeps) it must all still be in there. But, of course, that doesn't account for the fact that it may be doing more harm than good without regular changes as you pointed out. FWIW, Fauth recommends ATF as the fluid with that mod.

In any case, your post has "shamed" me into changing it! Thanks.

Bernhard · Jul 9, 2013

[quote="john robert bould"
Forks must be one of the most over-looked on a bike.
yearly oil change's are a real MUST!

This advice notwithstanding, every time you have reason to strip the forks apart, you should get a long broom pole and attach a long piece of rag and clean the bottom end of the alloy fork sliders, it’s surprising how much gunk drops to the bottom.

john robert bould · Jul 9, 2013

I bought some off Ebay, they arrived full of gray sludge, proberly never been oil changed in 20 years! as you say...wooden shaft and paper towel, then a was under a hot top and loads of soap ..crap city :!:
Most owners hate the refill, trying to get the oil past the spring, its a slow process.

Bernhard said:
[quote="john robert bould"
Forks must be one of the most over-looked on a bike.
yearly oil change's are a real MUST!

This advice notwithstanding, every time you have reason to strip the forks apart, you should get a long broom pole and attach a long piece of rag and clean the bottom end of the alloy fork sliders, it’s surprising how much gunk drops to the bottom.

Onder · Jul 9, 2013

I guess the older exposed spring forks are superior.
Looks matter more than utility I guess.

john robert bould · Jul 9, 2013

+1 , external springs must have a superior action, the First roadholder's where designed to use them. i dont rate the internal type , they bunch up and bind in the stanchion bore. Been playing today with internal .with out oil the spring grates when fully compressed, Now i can add something else...the cheapo ebay stanchions have a poor finnish inside, i bet the spring/ stanchion wall finnish is of no importance to the maker or retailer.
Ideal the internal should be smooth. better polished.

Onder said:
I guess the older exposed spring forks are superior.
Looks matter more than utility I guess.

Unclviny · Jul 9, 2013

I just bought fork tubes. The Emgo's were $99.00 where Forking by Frank was $199.00 and based on previous Emgo product ordeals I went with Frank.

Vince

concours · Jul 10, 2013

Unclviny said:
I just bought fork tubes. The Emgo's were $99.00 where Forking by Frank was $199.00 and based on previous Emgo product ordeals I went with Frank.

Vince

+1 They worked great when I bought from him years ago

Bernhard · Jul 11, 2013

john robert bould said:
I bought some off Ebay, they arrived full of gray sludge, proberly never been oil changed in 20 years! as you say...wooden shaft and paper towel, then a was under a hot top and loads of soap ..crap city :!:
Most owners hate the refill, trying to get the oil past the spring, its a slow process.

Far for me to give advice on filling fork legs with oil, how about removing the internal springs first from the Roadholders, then filling up with the correctly measured amount of oil :?: :idea:

79x100 · Jul 11, 2013

If you remove the springs from the forks, the damper rods will drop down and they're not very easy to get back up again...

The best option in my opinion is to bore out a pair of old fork nuts and weld a length of tube to each. If the bike is then blocked up on the mainstand so that the forks are fully extended and the nuts not screwed completely home, it is at least possible to put the correct quantity in both legs and walk away for half an hour.

The tubes simply act as a reservoir for the measured oil quantity.

Although not technically much 'quicker' except that both can trickle at once, the advantage is that I can go and put the kettle on rather than standing there.

Mike Sullivan · Jul 11, 2013

Sorry, where's the fire? Why the rush on refill? Just get a beer and savour the beauty of your bike whilst the oil drains down past that spring ;-) ...

Mike

MK III Commando

stockie2 · Jul 12, 2013

Good advice on the replacement of the oil. I have made and fitted teflon fork bushes, with Landsdowne dampers. The fork action is excellent, kind of supple and compliant. Just like modern bikes. I do get a rattle from the springs I think? I was trying to come up with a bush to hold the spring straight, even a plastic tube to cover the damper rod just short enough to not foul on full compression. Anyone tried this?

Cheers Richard

john robert bould · Jul 12, 2013

Hi Richard
The stock internal spring doe's not touch the damper rod,the stanchion wall takes up the slack.
Any rattles from the spring will be it rattling against the stanchion tube wall, the problem is the spring needs room to twist[bend] , restraining this natural bend will cause binding, as you know , a spring when compressed gets larger in diameter ,so a tube on the inside is No,No.
Glad you are enjoying the dampers. John lansdowne-Eng

stockie2 said:
Good advice on the e replacement of the oil. I have made and fitted teflon fork bushes, with Landsdowne dampers. The fork action is excellent, kind of supple and compliant. Just like modern bikes. I do get a rattle from the springs I think? I was trying to come up with a bush to hold the spring straight, even a plastic tube to cover the damper rod just short enough to not foul on full compression. Anyone tried this?

Cheers Richard

askdoctorday · Jul 12, 2013

The beer idea worked great for me. Pour a little oil, pour a little beer. A little oil, a little beer. A little more beer. Maybe a little oil. More beer, then a little more beer. Some additional beer, then a little oil. Then more beer.

Pretty soon the whole job is done, and you can relax and have a beer.

When I drained my forks on my '68, I am pretty sure they had never been drained before. The stuff that came out of there was beyond description. I don't even think it was carbon-based anymore, it had mutated into something from another dimension that does not include a periodic table. After cleaning and refilling (see above directions) the forks are supple and compliant, rides very nice. I was so excited I had a beer.

john robert bould · Jul 13, 2013

Watch you dont mix the two up, or you will end up well "OILED" come to think of it you where proberly well oiled anyway :lol: This fork oil changing should be done when the barbies on :lol:

askdoctorday said:
The beer idea worked great for me. Pour a little oil, pour a little beer. A little oil, a little beer. A little more beer. Maybe a little oil. More beer, then a little more beer. Some additional beer, then a little oil. Then more beer.

Pretty soon the whole job is done, and you can relax and have a beer.

When I drained my forks on my '68, I am pretty sure they had never been drained before. The stuff that came out of there was beyond description. I don't even think it was carbon-based anymore, it had mutated into something from another dimension that does not include a periodic table. After cleaning and refilling (see above directions) the forks are supple and compliant, rides very nice. I was so excited I had a beer.

kommando · Jul 13, 2013

Wonder if powdercoating the springs would reduce the rattling/noises, rear springs are powder coated.

Fork oil changing

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