[Ronny Grady]

I have read here several times that Banshee Scream's have a high leverage ratio suspension setup and are therefore prone to blowing shocks, especially in the long travel setting. I have read suggestions that you should get an Avalanche on a Banshee Scream or you are just asking for a blown shock.

On pinkbike's interbike interview with Scream they address this exact issue, stating that "because of the rising rate nature of the suspension the leverage ratio starts at 4.8:1, but in the negative travel of the bike you never blow up a shock... so it is not an issue... as the wheel moves through its suspension its leverage over the shock is reduced so it gets less... leverage as it approaches bottom out... for a ratio at bottom out of 2.1:1... and that is why these bikes very rarely blow out shocks"

http://www.pinkbike.com/audio/interbike2004/banshee.mp3

What is the skinny here?

 

[Kntr]

My buddy runs an 04 with a Avalanche and has never had a problem. If you get a Scream get an Avalanche and dont worry about it. Why would you want any other shock on a Scream anyway.

 

[CBJ]

Avalanche can be a good choice for that frame but it also depends on what type of riding you do. If you use the frame for many application from DH to XC style freeride then a 5th element, Swinger or Fox DHX could be a good choice as you have the option of tuning the shock to the different applications and the different shock positions.

 

[Jm_]

That sounds like BS. All he's saying is that it's a progressive linkage. There are plenty of examples of progressive bikes out there that were extremely high leveraged, and they blew shocks.

So it's highly leveraged and progressive....so what? If the shock is seeing high leverage ratios (as he said it does) it will increase the wear on the shock and eventually blow, regardless of "where" those leverage ratios are seen.

 

[go-ride.com]

The leverage rate decreasing throughout the stroke is typical of any progressive suspension linkage, and from my experience does help some with shock reliability. However, the Scream is still about 3.5:1 for overall leverage when used in the 7.9" travel setting. Most current 8" bikes use a 2.6:1 to a 3.0:1 overall leverage ratio.

In other words the Scream uses a 2.25" stroke shock to get nearly 8" of travel. The most 8" bikes use a 2.75" to 3.0" strock shock. I think reliability can be an issue with higher leverage bikes, but I also think lateral stiffness in the system is even more important. I bike that develops play in the linkage is more likely to blow shocks than one that stays true. The Scream does a good job of staying true and thus is easier on shocks than one might expect.

The big bonus for '04 is that the Scream will be available with the Fox DHX. Eventhough Fox has been a bit behind in shock technology the last couple of years, they still have the most reliable mass produced shock.

IMO an Avalanche shock is a nice upgrade for any bike, but a pricey one at about $600. May be hard to justify for a $1400 frame that already comes with a $400 shock.

 

[llkoolkeg]

Lots of things affect leverage on the shock- travel setting, wheelbase setting, wheel size, etc. I run both of my Banshees at a leverage of 3:1...the Vanilla RC on the Chaparral has a 2.00" stroke and I run it in the 6" travel position while the Scream's 2.25" stroke Vanilla RC is run in the 6.75"(7" claimed) setting. I haven't blown or serviced either shock whatsoever because I spring them appropriately and do not try to make up for too soft a spring rate with extra compression. Lots of bikes run ratios of 3+:1. Like most things in life, shock performance and reliability can not be boiled down to a simple formula or rule of thumb.

 

[math2014]

So whats the catch? Scream or demo8?

 

[ohio]

"because of the rising rate nature of the suspension the leverage ratio starts at 4.8:1, but in the negative travel of the bike you never blow up a shock... so it is not an issue... as the wheel moves through its suspension its leverage over the shock is reduced so it gets less... leverage as it approaches bottom out... for a ratio at bottom out of 2.1:1... and that is why these bikes very rarely blow out shocks"

Total BS. Where you blow your shock is at the initial part of the stroke, when the shaft speed is highest, under high speed hits. The problem with that leverage ratio is you have to crank up your compression damping very high to get any noticeable damping in most-used stroke of the shock (first 2/3). This makes it very difficult for the shock to handle the amount of flow you get in a fast, big, hit.

 

[llkoolkeg]

This makes it very difficult for the shock to handle the amount of flow you get in a fast, big, hit.

Well that's what the problem is, OH- you're using the wrong tool for the job. You should be using a bong instead of a shock.

 

[oly]

I rode the SH!T out of my scream for a good year. I had the fox for about 6 mos and never had a problem other than getting the proper spring. Being 230 before gear the higher leverage is harder to tune. I then swapped to a risse remote shock and ran that for about 6 months. Again, never a problem, and i rode that bike hard. Scott has it correct with the stiffness of the Screams system. Its rock solid. Flexy bikes increase the side loading on the seals and internal parts creating more chance for problems.

As far as the Question about pips comments? Im not an expert, but ive talked to pip many times and he really seems to have experience in what he does and he has been around the shore scene since the beginning.

 

[ohio]

Well that's what the problem is, OH- you're using the wrong tool for the job. You should be using a bong instead of a shock.

In that case the limiting factor is capacity (lung), as well as thermal threshold (throat). You can also get too much flow from the bypass valve (carb). Key there is proper tuning and setup, as well as high quality materials.