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xwhatsit
9th August 2007, 13:16
I just scored a very nice-looking pair of forks for the RS. http://www.trademe.co.nz/Browse/Listing.aspx?id=112834203 $60 for a pair of (allegedly) mint forks, I'm reasonably happy with that. By the time I'd bought new fork seals, dust covers, and a few hours to pull the bastards to bits... well I think it's worth it.

Additionally my ones have been bent at least once, and the stanchions are a bit shagged.

Once these get here, I'd like to look after them. Here are my questions:

Do I have to remove the stanchion from the leg to change the oil? This looks like a bit of a prick of a thing to do according to my Haynes. (There's no drain screw on these, btw)
Is it even worth changing the oil?
Are fork seals a good preventative-maintenance thing to do, or only worth fitting new ones if they blow?
The guy claims (and blurry picture kind of makes me think he's right) that the stanchions are in excellent condition. I'd like to keep them this way, to save wear and tear. Are gaiters worth fitting? Anybody know where I can pick up some cheapies?Thanks for the replies. Good suspension makes me happy, and the main appeal of my bike is threading it through twisty bits. This appeal has been dulling lately as the forks are pretty shagged out by now. Rear shocks (FVQs :shit:) will be next if I can get some money :D
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tri boy
9th August 2007, 17:44
Maybe Robert can help? Ya got them cheap, so spend a couple dollars on making them better.:yes:

xwhatsit
9th August 2007, 23:38
Maybe Robert can help? Ya got them cheap, so spend a couple dollars on making them better.:yes:

<hints id="hah_hints"></hints>Hahah yeah, I'd love to, problem being $100 is about my budget and I already spent most of it lol. After I graduate I'll buy an SRX600 and have Robert Öhlins it out for me :first:

Oh yes, I just thought of another question. In my Haynes manual (and apparently the Honda workshop manual too) it says to fill the forks with `Fork oil, or automatic transmission fluid'. Not particularly helpful, last time I was at a bike shop they had heaps of different grades of the stuff. What is a suitable grade fork oil for a 125kg-dry bike and 60-odd-kg rider with spindly 33mm forks?

Ta.

pete376403
10th August 2007, 21:08
I just scored a very nice-looking pair of forks for the RS. ... Rear shocks (FVQs :shit:) will be next if I can get some money :D
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FVQ - Honda got upset when some bike magazine wrote that means "Fade Very Quickly"

erik
11th August 2007, 07:58
I just scored a very nice-looking pair of forks for the RS. http://www.trademe.co.nz/Browse/Listing.aspx?id=112834203 $60 for a pair of (allegedly) mint forks, I'm reasonably happy with that. By the time I'd bought new fork seals, dust covers, and a few hours to pull the bastards to bits... well I think it's worth it.

Additionally my ones have been bent at least once, and the stanchions are a bit shagged.

Once these get here, I'd like to look after them. Here are my questions:

Do I have to remove the stanchion from the leg to change the oil? This looks like a bit of a prick of a thing to do according to my Haynes. (There's no drain screw on these, btw)
Is it even worth changing the oil?
Are fork seals a good preventative-maintenance thing to do, or only worth fitting new ones if they blow?
The guy claims (and blurry picture kind of makes me think he's right) that the stanchions are in excellent condition. I'd like to keep them this way, to save wear and tear. Are gaiters worth fitting? Anybody know where I can pick up some cheapies?Thanks for the replies. Good suspension makes me happy, and the main appeal of my bike is threading it through twisty bits. This appeal has been dulling lately as the forks are pretty shagged out by now. Rear shocks (FVQs :shit:) will be next if I can get some money :D
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1) No. Take the cap off and turn it upside down.
2) Might as well change it, fork oil isn't too expensive. I don't really know what sort of difference it'll make though. At a guess, new oil might help to prolong the forks life?
3) I'd only replace them if they were leaking.
4) If you can find out where to get gaiters, I reckon it's a good idea. Both my bikes have had nicks in the stanchions that wrecked the seals.

If you're going to change the fork oil, it might be a good idea to adjust the preload in the forks for the correct laden sag. You could stick the forks on the bike before pulling them apart, measure the sag, pull the caps off and measure how much available travel there is, then add spacers so that the sag is about 30% of full travel: http://www.strappe.com/suspension.html

xwhatsit
11th August 2007, 10:44
Thanks mate, really helpful. Glad I don't have to pull the stanchions out at least lol.

The preload/sag thing sounds interesting -- link says to use PVC pipe, which is good, as I have no idea where to find old 20c pieces any more hehe.

Ta. Still haven't heard from the seller, it would be nice if they're on their way.

James Deuce
11th August 2007, 10:57
Oil is for damping. The weight of the oil determines how quickly the oil flows through the damping holes (the size of which also determines how quickly or slowly the oil flows) and the damping rates generated are supposed to control the way the spring reacts to being compressed and extended. Compression and Rebound in other words.

Shit oil means shit suspension. It breaks down over time so you don't notice it degrading slowly, much like your own physical performance as you age. Decrepit saggy forks, seems to ring a bell, but I can't remember why.......

xwhatsit
11th August 2007, 11:13
So I'd be correct in thinking that for a light bike and light rider I'd want a light oil? 10W OK?

James Deuce
11th August 2007, 11:20
Maybe. Maybe not. Light oil might mean that the damping works too quickly giving you a very jarring ride. The oil weight isn't necessarily dependent on the weight of the bike/rider combo, but the weight of the spring and the size of the damping holes.

What does the manual say?

xwhatsit
11th August 2007, 11:23
Maybe. Maybe not. Light oil might mean that the damping works too quickly giving you a very jarring ride. The oil weight isn't necessarily dependent on the weight of the bike/rider combo, but the weight of the spring and the size of the damping holes.

What does the manual say?




<hints id="hah_hints"></hints>In my Haynes manual (and apparently the Honda workshop manual too) it says to fill the forks with `Fork oil, or automatic transmission fluid'.
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James Deuce
11th August 2007, 11:34
Cop out bastards.

Mind you fork oil is cheap. Try 10, if it sucks try 15.

xwhatsit
11th August 2007, 11:36
Cop out bastards.

Mind you fork oil is cheap. Try 10, if it sucks try 15.



<hints id="hah_hints"></hints>Haha cheers. The bike is so old perhaps they had only just invented pure fork oil ;)

James Deuce
11th August 2007, 12:07
It is really ATF or Hydraulic fluid. It's designed to be squirted back and forth through small openings at high pressure without frothing. It's just marketed as fork oil, but the fork oil bottles are smaller than a typical ATF 4 litre case, so you don't have it sitting around for 20,000kms before you refresh it.

xwhatsit
11th August 2007, 13:56
It is really ATF or Hydraulic fluid. It's designed to be squirted back and forth through small openings at high pressure without frothing. It's just marketed as fork oil, but the fork oil bottles are smaller than a typical ATF 4 litre case, so you don't have it sitting around for 20,000kms before you refresh it.



In the hope that I could get fork oil at the same grade as ATF, I checked up, but it looks like there are multiple grades of ATF too.

Ah well, I'll just go through those suspension tutorial things to sort out the preload and work out if I've got enough damping. Pulling the forks on and off a few times isn't much fun, though.

xwhatsit
17th August 2007, 21:52
Got the forks yesterday, unwrapped them, tested them a few times by pushing them. Good. Chrome absolutely mint, a few chips out of the black fork legs but still much better than originals. Went to the shop, asked the man if he had any ideas about which grade oil to use (bearing in mind it recommends ATF) and he said 10W should be alright. Why not.

The old oil in the new forks was still in good condition, I think it had been done relatively recently. Putting in the new stuff was a bitch to get the right amount -- using a jug from the kitchen some stuck to the jug so I had to add a little extra by eye, not ideal. I see why people use syringes, or better yet check the level (I wasn't sure if the existing level was correct, and it doesn't say in Haynes).

Condition improved slightly, there wasn't much in it, I think it might have been a change in oil weight more than anything else. At any rate it's good to change for the sake of the internal components, right?

Spent the afternoon changing them over and attaching my new headlight/indicators, which was a prick of a job by the way ;)

Just took it for a ride... unbelievable. It's amazing what a difference good suspension makes. Even in the rain the front end felt utterly planted. The road seemed quite a bit smoother too, lol. No more bouncing in the saddle. I went through a corner that normally at 50kph is a little exciting, and it just sailed through almost disappointingly easily (am I a masochist?).

The front wheel tracks a lot better too. I have a lot more precision. Also, if I take my hands off the bars (see thread re: Crashe for information :lol:) the thing goes in a straight line now until the engine slows down too much and you have to touch the throttle. Before it used to very gently pull to the left after leaving your hands off the bars too long and you'd have to shift your weight slightly (this is after straightening the forks -- shows you that you shouldn't. I'll add that the effect was very subtle, much like what you'd get if you had the rear wheel slightly out of alignment).

I'm well chuffed, although now it is even more obvious that the rear shocks are shithouse. Still, I know which end I want more traction at.

Thanks for your help guys.

James Deuce
17th August 2007, 23:12
Well done that man!

imdying
18th August 2007, 09:00
Stoked you've had a good result man :yes:

xwhatsit
19th August 2007, 17:10
Well I'm still pretty pleased with the front end. However...

Went out for a run to Piha today. Two things I noticed:

Over corrugations, the front seems to `lock up' and stop absorbing the bumps. I'm not too worried about this, from reading a bit I think this is to do with them being old-style forks with no emulators.
The front end seems slower to turn. Before I had the triple clamp down the forks a little, so I could get the clip-ons on top of the triple-clamp. This made it nice and nimble despite the shitty suspension. Now with the forks in correct position, I need to apply counter-steering and shift my weight around a lot more. Still not as bad as the GSXR600 I rode, but not the best. I think this is to do with the rake angle; my rear shocks are shagged and saggy, would good ones that lift the rear end a little improve turn-in?

Richard Mc F
19th August 2007, 17:32
[LIST=1]
Over corrugations, the front seems to `lock up' and stop absorbing the bumps. I'm not too worried about this, from reading a bit I think this is to do with them being old-style forks with no emulators.


fork oil level too high will do this, lower it 20 to 30 mm each side, and get each side at the same level ( use a piece of welding wire for a dipstick) and try again

xwhatsit
19th August 2007, 17:36
[list=1]
Over corrugations, the front seems to `lock up' and stop absorbing the bumps. I'm not too worried about this, from reading a bit I think this is to do with them being old-style forks with no emulators.


fork oil level too high will do this, lower it 20 to 30 mm each side, and get each side at the same level ( use a piece of welding wire for a dipstick) and try again

<hints id="hah_hints"></hints>Thanks for that -- will give it a try. I didn't think I overfilled it too much if at all, but you never know how accurate kitchen measuring jugs are lol.

Ta.

jonbuoy
19th August 2007, 18:59
Bike looks awesome mate - a million times better than the factory look.

imdying
19th August 2007, 19:51
<hints id="hah_hints"></hints>Thanks for that -- will give it a try. I didn't think I overfilled it too much if at all, but you never know how accurate kitchen measuring jugs are lol.

Ta.

Richard's advice is sound mate, measuring height ftw.

xwhatsit
19th August 2007, 20:39
Richard's advice is sound mate, measuring height ftw.

<hints id="hah_hints"></hints>Problem is finding the proper height it needs to be set to. It's not mentioned in the manuals, and there's no way I'd trust the initial level. Once I get it set right by having a play I'll post it up here so Google knows about it.

Thanks guys.

Anybody know much about improving turn-in? It felt like a mountain bike with the front end lowered a bit, now it just feels like a big bike up front. Should I drop the forks through the triple clamp a couple of centimetres again or start looking at the rear shocks?


Bike looks awesome mate - a million times better than the factory look.
Thanks mate :D But from the front, only from the front haha. Need to start looking for a little café `hump' seat.

imdying
25th August 2007, 09:38
<hints id="hah_hints"></hints>Problem is finding the proper height it needs to be set to. It's not mentioned in the manuals, and there's no way I'd trust the initial level. Once I get it set right by having a play I'll post it up here so Google knows about it.Yeah... might pay to ask Robert? He seems pretty forthcoming with his knowledge :yes: