YSS fork seals.

[oz_johnno]

after hitting a bump in the road last weekend and still bouncing on my seat a 1/2 mile later, I have decided its about time I gave beryl a suspension upgrade.

To this end I have ordered a YSS monoshock unit and a set of progressive fork springs.

do you think it would be a good idea to get the yss valves as well ??

what weight of oil do you guys use in the forks.... a bloke I was talking to here reckons you mix equal parts of 5 & 10 weight oil to make 7.5 weight.

Opinions please

OZ

[Bob_Roller]

If you can't get 7.5 wt oil locally, 10 wt will work just fine .

I wouldn't go too much heavier than that .

[tvrla]

I think Progressive springs are waaaay too stiff. You'll be bouncing over every bump instead of pogoing. Rather than replacing the springs with stiffer ones, it sounds like a rebuild or new fork oil was in order. If you do go with the stiffer springs, you'll need the stiffer oil to counteract on the rebound.

The stock units work very well when operating properly - I'd make sure they're up to snuff before any radical changes.

One thing about the current springs - is the sag correct? Do they bottom out?

[Barry]

I agree with wirespokes about the springs. I'd be looking at fork servicing and damping first. There's far too much brain washing around from suppliers and hearsay from others who should know better that suspension upgrades automatically means stiffer springs. People complain that the springs are too soft if the forks bottom out but the whole point is that under the most extreme provocation they should get close to bottoming out if the spring rate is correct. It might be that stiffer springs are needed but that should ideally be decided properly and one way is by measuring unladen and laden sag.

With the bike on the centre stand measure the length of exposed stanchion. That's measurement #1

Roll the bike off the stand and with someone else holding the bike upright measure again that's measurement #2. The difference between #1 and #2 is the unladen sag.

Sit on the bike with your usual gear on and have someone measure again that's measurement #3. The difference between #1 and #3 is the laden sag.

I'd be interested to know your figures. You should be getting something in the region of 30mm unladen sag and 45mm laden sag. It's not quite this simple but as a first indicator if your measurements are substantially more then maybe you do need stiffer springs. If your sag figures are not substantially more then you probably don't.

Also agree that if you do put stiffer springs in the stock damping is not likely to be able to control them and you should match the springs with heavier oil. Unless you really needed the stiffer springs in the first place this is might end up giving you a stiff ride. You can mix same brand fork oils 50/50 and get an approximate mid viscosity. Surprisingly it's not exact but the difference is not worth worrying about if you stick to a 50/50 ratio. The errors are bigger if you are trying for something like 25/75. There are online calculators around if anyone wants to be precise.

[tvrla]

I'll echo Barry's advice, but add one thing: if the sag is too much, the first thing I'd do is add a pre-load spacer to the top of the fork springs. Mostly, these are made from a section of white PVC pipe.

One other thing I didn't say - if the YSS valves you mentioned are cartridge emulators for the front forks - I'd be interested in knowing more. First off, what did they cost? I know of one place that sells them for $50 and have been keen on installing a set.

Has anyone already been there? Done that? I installed Race Tech Emulators in my R80G/S and it was a dramatic improvement. I'm really sold on that technology and want to mod the LS also.

[montmil]

I have yet to find a vendor that offers the cartridges for our R65 front forks. If anyone trips across a verifiable source, please post up.

[Barry]

I've never seen them advertised but if you are prepared to do some lathe work on the damper rod top then I'm sure suitably sized cartridge emulators could be made to fit. Shorter springs are needed and it's a one way street for the damper rods. No easy way of going back to stock.

[tvrla]

I can't imagine wanting to return to stock after running emulators. They are that much of an improvement!

I'll look around at my source, but think they'll work fine in our forks.

In my G/S, I shortened the springs by an inch to compensate for the emulators, so springs weren't needed. A heavier rider may need custom stiffer springs.

The idea with these things is to separate compression from rebound - make them individually tuneable. Run heavier oil to get the rebound where it needs to be, then adjust the emulator for the right compression damping.