Ducati Monster Forum

Moto Board => Racing & Trackdays => Topic started by: mszilves on May 31, 2013, 10:16:41 AM



Title: Shock upgrades for trackdays
Post by: mszilves on May 31, 2013, 10:16:41 AM
Hi guys, not sure if this is the section for this, but have a question regarding upgrading shocks.

I have a Monster 796 that I do a fair amount of track days with. I typically ride in the 200 level groups and can keep up to the faster guys. I've upgraded the forks on the Monster to fully adjustable Showa's, but both ends currently have the stock progressive suspension.

I'm looking at either upgrading to the Ohlins (which essentially is the same as stock with rebound adj. only, but is linear rate spring) or getting a Penske 8983 with seperate reb/comp.

Does seperate reb/comp make that much of a difference over the Ohlins unit? This is not so much a question of which brand is better, but more of what can I expect from a 2way vs 1way adj shock. Is it worth the money?

Just wanted to get some opinions on what would be the best way to go. While the current suspension feels "mushy" when pushing the bike around hard, the bike seems pretty well setup.


Title: Re: Shock upgrades for trackdays
Post by: zooom on May 31, 2013, 10:58:17 AM
which locale are you in? perhaps a reccomendation of someone local to you for to set your sag and look at your weight versus spring rate and the other variables would be a viable option as well?


Title: Re: Shock upgrades for trackdays
Post by: ducpainter on May 31, 2013, 11:36:52 AM
I wasn't aware that Ohlins made a rebound only adjustable shock. My Ohlins has both rebound and compression damping.

I'd try a linear spring for your stock shock, and forks, first if you cant get the sag numbers right.

That said a fully adjustable shock is nice.


Title: Re: Shock upgrades for trackdays
Post by: Raux on May 31, 2013, 11:47:09 AM
you can upgrade the springs on the front to linear as well as the back with the stock shock/dampers
and shock valving on the front can be done to the showas
for the rear, someone is trying a 999 showa, wait for that test and then see.


Title: Re: Shock upgrades for trackdays
Post by: Speeddog on May 31, 2013, 11:49:44 AM
The Ohlins that's available for *96/1100 Monsters has a single adjuster that changes both compression and rebound.
It's a needle and orifice that bypasses the piston.

All Ohlins that have an adjuster on the shaft work the same way.
Some have an additional circuit (or circuits) on the reservoir that adjusts compression only.


Title: Re: Shock upgrades for trackdays
Post by: mszilves on May 31, 2013, 01:08:12 PM
The Ohlins that's available for *96/1100 Monsters has a single adjuster that changes both compression and rebound.

Yes thanks for adding that speeddog.

My stock suspension is definitely setup for me (I'm 180lbs without gear), rider sag is well within range (40mm up front, 35 in the rear), and overall the suspension seems pretty compliant. It just feels mushy on the track, this might just have to do with the fact that it's progressive?

What I was wondering was what I could expect to gain from having rebound/compression seperately adjustable?

If I just put linear-rate springs on the stock suspension, would the stock damping still work properly?

I'm trying to figure out what would get me the best bang for the buck in terms of suspension upgrades without going to the full blown rear racing shock/new cartridge internals route.


Title: Re: Shock upgrades for trackdays
Post by: ducpainter on May 31, 2013, 01:18:51 PM
Yes thanks for adding that speeddog.

My stock suspension is definitely setup for me (I'm 180lbs without gear), rider sag is well within range (40mm up front, 35 in the rear), and overall the suspension seems pretty compliant. It just feels mushy on the track, this might just have to do with the fact that it's progressive?

What I was wondering was what I could expect to gain from having rebound/compression seperately adjustable?

If I just put linear-rate springs on the stock suspension, would the stock damping still work properly?

I'm trying to figure out what would get me the best bang for the buck in terms of suspension upgrades without going to the full blown rear racing shock/new cartridge internals route.
You might want to get closer to 25-30 mm for the track. I think you have it set up too soft spring wise.

You can also play with oil weight/level in the forks.


Title: Re: Shock upgrades for trackdays
Post by: mszilves on May 31, 2013, 01:26:30 PM
You might want to get closer to 25-30 mm for the track. I think you have it set up too soft spring wise.

That's the thing, since the stock suspension is progressive, it's hard to dial it in precisely. Regardless of the sag, you'll run through the lighter part of the progressive springs quickly which tends to make the bike feel soft. Now if I just upgrade springs, will the stock damping still be sufficient, or do you HAVE to re-valve?


Title: Re: Shock upgrades for trackdays
Post by: ducpainter on May 31, 2013, 01:36:13 PM
That's the thing, since the stock suspension is progressive, it's hard to dial it in precisely. Regardless of the sag, you'll run through the lighter part of the progressive springs quickly which tends to make the bike feel soft. Now if I just upgrade springs, will the stock damping still be sufficient, or do you HAVE to re-valve?

True, but the increased preload will compress some of that lighter spring out of the equation.

At your weight the spring change will not require a revalve.

That said, Showa Monster forks are always better with an upgraded valve, and if you can afford it and have a good suspension shop I'd get it over with. If you've gone with SBK Showa forks the valve is much better.

Depending on where you live and which track you ride most often the RaceTech stack recommendations may or may not work for you. Their recs can be pretty harsh on bumpy roads/tracks.


Title: Re: Shock upgrades for trackdays
Post by: MadDuck on June 01, 2013, 02:26:33 PM
That's the thing, since the stock suspension is progressive, it's hard to dial it in precisely. Regardless of the sag, you'll run through the lighter part of the progressive springs quickly which tends to make the bike feel soft. Now if I just upgrade springs, will the stock damping still be sufficient, or do you HAVE to re-valve?

Correct me if I'm wrong, please.  My understanding of a progressive spring is that it is on the soft side at the top of the travel and gets stiffer, faster as it is compressed as opposed to the linear spring which is compressing at the same resistance all the way through.  So, that through the first bit of compression there should be, effectively, no difference between the two types of springs. Yes/No?


Title: Re: Shock upgrades for trackdays
Post by: ducpainter on June 01, 2013, 05:36:07 PM
Correct me if I'm wrong, please.  My understanding of a progressive spring is that it is on the soft side at the top of the travel and gets stiffer, faster as it is compressed as opposed to the linear spring which is compressing at the same resistance all the way through.  So, that through the first bit of compression there should be, effectively, no difference between the two types of springs. Yes/No?
Nah...progressive springs are a compromise plain and simple.

They are why the OP is feeling that the suspension is mushy.


Title: Re: Shock upgrades for trackdays
Post by: mszilves on June 03, 2013, 03:08:20 PM
Nah...progressive springs are a compromise plain and simple.

They are why the OP is feeling that the suspension is mushy.

That definitely sounds like it could be it! :)

I'm going to go with an Ohlins custom valved/sprung for my weight and trackday use (I assume they will use something similar to Superbike valving), and put some linear springs in the front. If that's not enough, I'll get the Showa forks re-valved.


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