[Lelebebbel]

I know there have been many threads about this in the past, but I figured maybe we can collect some up to date information.

My engine is finally sorted, so now on to the suspension. Canadian back roads can be a bit harsh, and I do like to press on occasionally, so I'm looking for something a bit better than the 24 year old Sachs unit currently in my bike. The spring rate feels too high to me (I'm about 190lbs with my gear), and while I haven't messed with the C/R settings much, I think the shock should at minimum get a rebuild before I spend much time with that. The back end is harsh in compression and somewhat "wallowy" at the same time.
So between springs and a rebuilt, I might as well consider replacing the whole thing.

What is available and recommended for a carbie these days? Is Öhlins the only popular option? Or should I get a Showa from a different SS and have that rebuilt/sprung?
I'm not going for lap times and I don't necessarily need an expensive cutting edge racing shock, but I wouldn't mind something a touch longer or length adjustable.


As for the forks, I have constant rate springs already of unknown spring rate. I will be pulling them out and having them measured, as well as probably drop in some Race Tech goodies. I'd do the GSXR conversion, but I believe this is not easily possibly since my CR has non-adjustable forks.

 

[Combi245]

Nitron - way better than an Ohlins in my opinion. Rebound and dampening are all separate and you can upgrade them easily. Excellent shock for the money. I can not speak of them highly enough so much so that I am going to use them on my Hossak inspired front suspension system that I am working on. Front forks just get some Showa's and throw away the internals - there are plenty of drop in kits that can be purchased to sort that side of things with out going to the GSXR route.

 

[jooced]

Are you a big dude? I am a big dude. 5'11" and 245#. Took some fiddling but the stock suspenders are now working surprisingly well now. Not sure how you set up but for a dude like me I go big on preload. For me I shoot for 15-18MM sag front and rear and THEN I fiddle with adjusters. On fronts I got one line showing just barely out of view. Rebound about 5/8 of turn in from full soft and compression about 7/16 turn in from full soft. Rear rebound about 4/5 turn out from full hard and compression about 3/4 turn in from full soft.

I found through trial and error those original sag suggestions from wayyyyyyy back ( Think it was Nick Lenatsch who started it of Cycle World?) when were for dudes who are 5'5" and 140# sopping wet in leathers. Nothing wrong with running heavy preload - for me it actually makes adjusting the rebound and compression quite a bit more easy and precise. The roads here in Wichita where I am staying while house being built in NM the roads flat-out-suck. The expansion joints are profound and the blacktop has been heat/cold cycled to hell and back with a fault line full span about every 20 feet on average.

Couple all that rough with my fat ass - hauling ass on a Duc 900SS and it actually performs damn fine.

 

[jooced]

As for the forks, I have constant rate springs already of unknown spring rate. I will be pulling them out and having them measured, as well as probably drop in some Race Tech goodies. I'd do the GSXR conversion, but I believe this is not easily possibly since my CR has non-adjustable forks.

Ever ride dirt bikes? Simply swapping the ATF for 20W fork oil can make a DRAMATIC difference with both compression and rebound.....cheap and easy to modify by cutting with 10W fork oil to make a hybrid mix of weights from 11-19W........What are to roads like? How tall are you? Your height plays a big part with where your center of gravity ends up - ass heavy ~ bars heavy ~ even split, etc, etc.....this plays very heavy into precisely adjusting what you have to work best for your frame / seating / riding style + roads.......

 

[Lelebebbel]

I'm 6'1" and 190lbs with riding gear on, so not that big I guess. Although probably bigger than the average italian in 1994? Which does make me wonder about that spring rate in the back.

Mine has Showa front forks, but being a CR, it has the ones that aren't drilled for the external adjusters. No preload or rebound either. I believe that means I can still drop in Race Tech valves and call it good. The GSXR conversion is an option but it would mean having to find two used forks (adjustable showas and the GSXR), so getting some Racetech drop in valves will be a lot easier.

The forks feel a lot better to me than the shock right now, at least the spring rate is in the ballpark. I suspect that the bike would benefit from a slightly raised rear suspension though.


That Nitron stuff looks very nice Combi. It does translate to over $1k CAD though. As many of us here, I am well past any reasonable ratio of "money spent on bike : what bike is worth".

 

[jooced]

I'm 6'1" and 190lbs with riding gear on, so not that big I guess. Although probably bigger than the average italian in 1994? Which does make me wonder about that spring rate in the back.

Mine has Showa front forks, but being a CR, it has the ones that aren't drilled for the external adjusters. No preload or rebound either. I believe that means I can still drop in Race Tech valves and call it good. The GSXR conversion is an option but it would mean having to find two used forks (adjustable showas and the GSXR), so getting some Racetech drop in valves will be a lot easier.

The forks feel a lot better to me than the shock right now, at least the spring rate is in the ballpark. I suspect that the bike would benefit from a slightly raised rear suspension though.

You can adjust preload by using shim washers / precise cut piece of fence pipe between caps and springs when you go back together with them. A 3/8" or 10MM spacer should get you in the ball park of sag for your weight, one in each leg. The difference from the word go will be profound. I have been doing that for decades now on all of my historical bikes. You are tall which means if you are not crouching into the windscreen, you are riding your bike ass-heavy. I would say that if you move your bars a bit forward to move your center of mass more forward you will move weight off the rear. You could also drop the forks into the trees by about 10-15MM which will further move weight forward and help balance out the CG. These are all tricks learned from riding / racing old Suzuki T500's / PE175's / RM 250's and Honda VFR 750 Intercepters....It does not sound like much is changed but I tell you it changes how the suspension behaves dramatically.

 

[Lelebebbel]

Good point about the center of gravity. I have my bars as far forward as they will reasonably go without hitting the fairings at full lock, but I should try dropping the forks down a bit.

As for the rear shock, does anyone know if the Sachs units can be rebuilt/re-valved somewhere?

 

[psyopper]

By the time you get the work done rebuilding the shock you're half way into the price of a new Penske shock, which will be a superior shock in all respects, have a wide array of Hyperco springs available, and have fully independent C/R adjustment and length adjustment too.

Edit: Just looking through fleabay and it seems like shock prices are... shocking. Still probably a better option than the OEM Sachs, to which every expense was spared in it's development.

For the forks - look for the Andreani cartridge kit. Uses mostly Ohlins pieces (they manufacture many of the parts for Ohlins). Might not have one specifically for your fork, but they are out there for the Sport Classic and 900ss-ie length forks, which can be had pretty inexpensively. These kits isolate compression to one leg and rebound to the other, which makes adjusting much easier.

 

[RockAZ]

Penske shock prices are shocking,...

Start with the Racetech upgrade on the front, grip the tank hard with your thighs and ride until you figure out the next step.

 

[jooced]

Good point about the center of gravity. I have my bars as far forward as they will reasonably go without hitting the fairings at full lock, but I should try dropping the forks down a bit.

As for the rear shock, does anyone know if the Sachs units can be rebuilt/re-valved somewhere?

Here is an idea - - Measure your shock unloaded end to end. Call up some motorcycle recyclers and look for a remote reservoir unit from a Suzuki RM series with their "full floating" design dirt bike (Preferably) which can get as close to the measurements you need and bolt that puppy in there. These units are cheap and can be serviced/rebuilt by any competent hydraulics shop. The remote reservoir allows you to gain access easily.

The Suzuki units with their valving will give you more than you can ask for at a very reasonable cost - - -

 

[ducvet]

The problems with your Sachs shock is you cannot buy parts for them so if the shaft is bad or the seal fails you are out of luck. Other than that fact I feel they are superior to the showa as the valve is much better than the oem carby showa that was far too restrictive. Yes the carby showa can be improved with a new valve and spring but by the time you do that I feel you are better off biting the bullet and buying the Ohlins or Penske.

Much of the harshness from the Sachs is from the prog rate spring that is oem. Simply ditch the rear spring for one of a reasonable rate and you will find it is much better. damping wise I would not change the shim stack on the sachs valve for the spring you will use. Given your weight I would put you on a 7.5 or 8.0 rear spring depending on use and rider preferences. I have the same shock on my track 7500ss and with good oil and the right spring I have no need to put the ohlins or penske ( that I own) on as I find the shock works just fine.