Re-valve M900sie forks, overkill for street riding?

TelemarkSean · February 11, 2016, 09:47:43 AM

I'm looking for some input. It's fork overhaul time. My bike has the stock fully-adjustable USD Showas with about 15k miles on them. The front end is too light for me. It dives pretty bad and the dampening is poor. So a respring is in order along with general cleaning and new oil.

From these forums, it seems like a some people aren't really happy with the stock valving. I could have the forks revalved but that changes this from a $200 job to something like a $500 job (includes springs, valve kits, seals etc).

I'm wondering how whether the better dampening will really be apparent on the street. Thoughts?

Thanks.

Edit: It's a 2001 M900sie, fully stock.

ducatiz · February 11, 2016, 09:56:01 AM

Do a little more shopping on a rebuild.

I get springs from Sonic Springs, custom made for $90/pair. You give them the fork specs and how much your fat ass weighs and tell them what kind of performance you want and they custom roll you some springs.

Shop around for the valves too.

Setting the forks to your correct weight and profile will change your life.

ducatiz · February 11, 2016, 09:56:57 AM

A quick google found that Race Tech Gold fork valves for the Showas run around $150

TelemarkSean · February 11, 2016, 10:28:41 AM

Yeah, I'm sure I can save a little $$ by sourcing parts myself but I'm having these done by a professional and the labor charges around here are pretty reasonable. The $500 is an all-included estimate from a reputable shop. If I keep the stock valving, the job is 1/2 the cost.

Speeddog · February 11, 2016, 10:38:04 AM

Price on rebuild and upgrade depends a lot on whether you're handing the forks to the shop, or riding the bike to the shop and having them do it all.
So, which way are you planning on going?

The vast majority of bikes I work on are street-only.
I've never had a customer say "I wish I hadn't upgraded my suspension".
Usually they say "I wish I had done that a long time ago."

Getting your bike sprung correctly for your weight is step one, and the biggest bang for the buck for most people.

ducatiz · February 11, 2016, 10:46:54 AM

Quote from: TelemarkSean on February 11, 2016, 10:28:41 AM
Yeah, I'm sure I can save a little $$ by sourcing parts myself but I'm having these done by a professional and the labor charges around here are pretty reasonable. The $500 is an all-included estimate from a reputable shop. If I keep the stock valving, the job is 1/2 the cost.

you're on your own then. the valving is most of the labor imho. if he's replacing them, the labor on the springs should be ZERO because they already come out.

it's not rocket science to do it though. you'd be surprised how easy it is.

TelemarkSean · February 11, 2016, 10:55:40 AM

Quote from: Speeddog on February 11, 2016, 10:38:04 AM
Price on rebuild and upgrade depends a lot on whether you're handing the forks to the shop, or riding the bike to the shop and having them do it all.
So, which way are you planning on going?

The vast majority of bikes I work on are street-only.
I've never had a customer say "I wish I hadn't upgraded my suspension".
Usually they say "I wish I had done that a long time ago."

Getting your bike sprung correctly for your weight is step one, and the biggest bang for the buck for most people.

I'll remove the forks and ship/deliver them.

I'm sure I could do them myself. I'm actually pretty handy. Rebuilt a motor and did a whole lot of electrical work on a few bikes. For some reason I'd prefer to have a pro do the suspension, particularly when it comes to selecting springs and oil and all that.

ducatiz · February 11, 2016, 10:58:45 AM

if you can do a motor, you're well overqualified to do the forks. they are actually pretty simple inside

spring selection is a matter of weight and taste.

Howie · February 11, 2016, 09:33:20 PM

Definitely worth it. The stock springs are both too light for many of us and progressive to a fault. High speed damping is too harsh. The work itself is easy. The secret to success is the set up of the shim stack, usually done best by a local guru.

MonsterHPD · February 11, 2016, 10:06:01 PM

Some of you may have heard me say this before, but re-valving the stock Showa 50/54 mm forks won't help much, and might even make things worse. Reason: The damping cirquit is a cost-saving design that does not really work. A re-design is necessary, but not quite cheap, or you adapt GSXR cartridges to fit your forks.

If your forks are the 43 mm stachion version, Ã–hlins R&T springs will fit, you just have to make some new spacers to make up for the shorter springs. The stock ones are, as mentioned, far too soft and any prgression comes too late in the stroke.

clubhousemotorsports · February 12, 2016, 09:06:26 AM

What needs to be done depends a lot on you and what you ride.

what are your roads like
smooth
motocross track that appears to be paved

What are you trying to fix?
dive
harshness in compression
bottoming
handling

Springs alone will get you a big improvement, less dive more travel and more supple suspension.

I respectfully disagree about the value of changing the high speed compression valves the oem valve on the lower end showas can be improved a great deal and is worth doing IF you are having problems with high speed compression. we have been using this setup for the past 19 years with noticeable results . There may be a better system for sure but it does not mean it is not worth the effort. there is almost always a better system, it just depends on do you need to pay top price for smaller and smaller and smaller gains.

In example 90% of people could not tell is a fork was coated with DLC or tin coated, it does help but if the gain is so slight it is a waste of money for most. Ohlins cartridges (and most others) do improve greatly over a stock fork but improve less over a well set up stock fork. Rider sensitivity is important to note as I have had expert racers who couldn't tell if their forks were full of sand or oil.

My problem with most cartridges is the cost gets you close enough to a used complete ohlins fork, resale will always be better on the complete unit as cartidges are largely unseen so it is comparable to engine work, well worth doing but not much for resale.

TelemarkSean · February 12, 2016, 09:12:04 AM

Quote from: howie on February 11, 2016, 09:33:20 PMHigh speed damping is too harsh. The work itself is easy. The secret to success is the set up of the shim stack, usually done best by a local guru.

Is this done without modifying the stock valves?

The shocks on my bike are the 43mm fully-adjustable Showas which I believe were stock on the 2001 model.

clubhousemotorsports · February 12, 2016, 09:34:09 AM

No high speed damping IS the valve on the showa.

A 2001 fully adjustable showa on a monster is the worst case scenario (IIRC) I see as Showa had a batch go out with an issue where the fork bleeds too much oil and the rebound circuit does not work as it should. I have done a number of these where the compression works fine but the rebound is insufficient. This is not the case on the older showas back to 91 and later than 2001. I do not see this issue on any of the ST series or SS forks even in the 2001 year this is why there is something off on the 2001 monsters (possibly even 900s only as I do not remember this on s4) all with the same spec internals.

The last 2 sets of 2001 adjustable forks we had one customer switch to superbike forks and the other I switched to superbike internals. With a 2001 you are taking a chance you will have the gremlin but I cannot say it would be 100% Springs only is good to go but you still may find you have to bury the rebound and that is never a good idea if you can help it. Keep your eyes open for a set of 916,748,996 forks and swap the damper unit. The fork will be within a few mm of the same length when done and you will have good valving. You still will need to re-spring unless you are 250+lbs.

Armor · February 12, 2016, 09:43:53 AM

I have a 2004 M1000 and had Ohlins valves installed. It made a pretty big difference. I don't know if they still sell these valve kits for the showa forks.

clubhousemotorsports · February 12, 2016, 09:59:03 AM

I believe they still do sell the ohlins valves, yes they would be good.

I prefer the racetech gold valve for one simple reason, they are more free flowing than the ohlins valve and in new england the roads are so bad I want the most free flowing design I can get.

Truth told the old showa design has been around since the early 90's unchanged in many bikes (just found them in a set of hd1200 sportster forks) it is so poor for bad roads that it would be hard to not improve on it.

That said I still am running the crappy valve on my 750 track bike because most of the tracks I ride do not have high speed compression issues.

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Re-valve M900sie forks, overkill for street riding?