Beta Suspension

[billyt]

While your idea will slow the forks compression speed down the probability of the fork being harsh has been increased and the front to rear balance of the bike will be off. Also after being heated thicker oil is going to change viscosity more than thinner oil will. I am certain many people use this technique as an inexpensive solution to having too soft a fork spring. Having the correct front and rear springs made for your ride weight costs about $230. The tuning process could be made easyer if the suspension components had compression speed adjusters.

I will address each of your comments:

First off it is not my idea! Lots of people I know use this simple, quick, cheap method of stopping the bottoming out.

"While your idea will slow the forks compression speed down the probability of the fork being harsh has been increased and the front to rear balance of the bike will be off."

Obviously you have not tried this as there is nothing harsh about it. It is a slow controlled compression of the front forks.It is a proven method!

The bottoming out scenario we are talking about here is a downhill or a drop off, so the bike is already out of balance.

"Also after being heated thicker oil is going to change viscosity more than thinner oil will."

That comment is lost on me ?????

"Having the correct front and rear springs made for your ride weight costs about $230"

How the hell do you figure out $230? for front and back end Most of the springs for trials come from Europe and a rear spring alone cost anywhere from $200 > $300 alone with shipping , duties etc.

Think of this, to get a heavy front spring to compress one needs to place more energy transfer into it. That can be done by the rider being heavier or proper loading of the riders weight into the front forks. This bottoming out issue is not a simple as just installing a heavier spring. A heavier spring will take more energy to compress it obviously, but once compressed it will return a lot more energy back in the return stroke making the rebound quicker and less controllable. To overcome this more energy and stop it rebounding far to quickly you have no choice but to adjust the re-bound adjustment screw and possible there will not be enough adjustment left to slow the fork down due to rider weight and/or how heavy a spring you put in, or you can always change the re-bound fork oil for a heavier oil and between the re-bound adjuster and heavier oil get the desired effect you seek OR you will be caught in a vicious

circle of springs/oil/adjustments etc.

Do you want a controlled fork or a pogo stick?

Basically trying to stop bottoming out by just a spring alone will transfer the problem into the return stroke. It is much easier to dissipate the energy in the return stroke of a lighter compression spring than a heavy return spring. By using a heavier fork oil in the compression side less energy is transferred into the return stroke.

Basically if it takes 200lbs of force to compress a spring it will spring back with maybe 80% of that energy.

Here is something for you to think about based upon physics and several riders experiences.

I will exaggerated this in order to make my point. If one were to remove the front forks ability to compress and you road forward pulling in the brakes and try to do a nose wheelie to kick the back end to one side it would be EXTREMELY difficult to do! Why? In making the front end so ridged one has changed the pivot point at the triple clamp making it much higher with reference to the back end of the bike. When the forks travel down as they do in a normal bike front end they lower the pivot point with reference to the back end. If the forks could travel down further than normal it would much easier to get the back end in the air. The point here is this. I have witnessed and tried guys bikes who had stiffened their front end to the point that they could no longer get the back end of the bike up in the as they could prior to making the front end so stiff. You want all the travel in the front, you just want to do it in a controlled manner.

A REALY stiff front set of forks will cause the front to push rather than turn. Once again the lower triple clamp effect from the forks compressing is critical to a turning correctly. In the prior example of removing any movement of the front forks one would have a very hard time in making the bike tract around a wet loose turn.

Your milage may vary depending upon your weight riding style etc. To me the bottom line is that everybody should be able to customize their bike the way they want to. In doing so they should know what technical options are out there to do so. Changing springs and re-valving or shimming is one way, changing oils is another way or a combination of both. To each their own. In either case starting off simple is always the way to go, one step at time, change one thing and see what happens

I also agree with Dave Rhodes comment about not making any changes until the bike has a good few hours on it!

One other distinction is this: I have seen people get confused with the forks mechanically bottoming out Vs Hydraulic lock. Mechanically Bottoming out is the fork reaching the end of its travel, hydraulic lock is when they have put too much oil in the fork!

To check this out or verify which one it is do the following: wrap a cable tie around one of the fork sliders. Slide it all the way down to the fork seal. Go ride, the cable tie will be pushed up by the travel of the fork and will stay put on the slider as to were it was slide up by the fork leg as it travels. The cable tie will become a witness as to the amount of travel the fork is making. Common sense when looking at were it stays will tell you if your are using a lot of suspension travel or barely any. In other words if you have six inches of travel in your forks and the cable tie has moved two inches from the travel of the fork leg and you felt the fork being restricted and at the end of its travel you properly have too much oil in the fork i.e. hydraulic lock.

On the other hand if the cable tie has moved all the way up the leg and you felt the forks bottoming out then you are mechanically bottoming out the suspension.

PS: Ron it is TRAYNOR not Trainer later mon ami.

Edited September 30, 2011 by BillyT

[billyt]

Dan you bring up a VERY important point. Traditional trials tells us that one should be able to stand on the pegs and move one's body weight up and down, subsequently the bike should move up and down as one unit, front and end back end in harmony, with todays riding style who the hell knows? LOL. Lots of usage of stored energy as Dan mentions.

Wow, I've been off the forum for a while, busy at work, and all hell breaks loose. I seem to remember hearing Beta has a financial interest in Paioli but that may be incorrect. Without going into a long diatribe about suspension I will agree with Billy T's assessment.(note 1.) The Beta forks are not bad. They’re no factory Showas but they don’t cost 20G$ either. My understanding of the Paiolis is also rebound damping in one leg, compression damping in the other.

As for suspension settings that are the biggest detriment to riding I’ve found the most common issue is a mismatch of the front and rear. Almost without exception when someone says they can’t hold a line in bumpy bits I can stand their bike up and put a foot on the peg and push and one suspension will move and the other won’t move at all. The absolute spring rate and preload on the suspension as a whole is largely amenable to rider preference (note 2.) but a difference between the two is problematic. It comes back to centering as almost anything in this sport does. A too stiff front end, aside from beating the snot out of your arms causes the rear suspension to collapse changing geometry and storing disproportionate energy in the rear shock that will release before the front end has settled. A too stiff rear will over compress the fork changing geometry in the other direction and storing excess energy in the fork that releases just about the time your feet are bouncing off the pegs from the rear not compressing.

With modern techniques the imbalance is equally problematic. Modern techniques use energy stored in the suspension to do things impossible with traction alone. When that energy is not stored in the correct ratio you can bet that at least one wheel isn’t going to do what you want it to do.

So before you do any fine tuning of spring rate, damping and preload you have to make certain the front/rear balance of the system is correct or you’ll be chasing ghost effects from the imbalance for a very long time.

NOTE 1. Billy T. and Jon S. have forgotten more about motorcycle tuning (and machining and metallurgy…) than I’ll ever know.

NOTE 2. (Jordi Tarres’ suspension always seemed to be over-sprung with little damping, Eddie LeJeune’s suspension was as soft and squishy as a sneaker full of poo. Therry Michaud sort of split the difference)

NOTE 3. I see while I was thinking and typing Liviob beat me to it on the balance issue. Well played sir, well played.

Edited September 30, 2011 by BillyT

[outlaw dave]

One of the things we tell our customers is don't make any adjustments on a new bike, until the forks have had a chance to "Bed in"

this can take as long as 3-4 hours depending on the model. - failure to do this by cranking up the compression can lead to blown fork seals. Outlaw Dave

[nif40]

Sorry to back the conversations up a bit, but I don

[billyt]

"If we all agree to the above then we can proceed. If not, lets get the basic design of the forks hashed out so we can make set-up changes and know what we are changing otherwise its meaningless. Again, maybe I am the only one who isn't in the know, but I doubt it."

WHY................

Some of the good folks on this site have figured out how these forks work long before you! Some people do not care in how they work they just want them to work. The bike has to work in harmony not just a all out intensive focus on a set of forks! Some folks need to know all the technical details in how every part works on the bike. I am by nature the latter as it seems you are also! Nothing wrong with that at all.

I have been curious about how all this works from a technical view point for about thirty two years now in the trails arena. God I messed up a LOT of bikes and bikes parts due to my curiosity. Hopefully I have learned something from my apprenticeship of life in trials? I applaud your curiosity and encourage it, but do not forget those whom came before you!

Please tell us how long you have been riding trials?

I can bet that you rode motocross or enduros before venturing into trials?

There is no doubt that you have some technical abilities, but you come across as newbie to trials and one who will not take the advice of those who have been there done that! I am by training a degreed Mechanical & Electrical Engineer and can talk technicalities and theory all day long with you. BUT there comes a time to put the calculator and books aside and trust experience, in both experiments, years of riding TRIALS, making many mistakes in trying things, by those who came before you with technical abilities, and there are many!

Do you honestly think that you are the first one to try get specs from Paoli, Beta on the forks?

Are you trying to say that changing the oil viscosity in the compression fork does nothing? You need less theory and some practicality. If you are saying this then you are also saying that all who have tried this have their head up the a*** at the results!

"If my understanding above is correct, then oil viscosity does not have any affect on the magnitude of the compression resistance which means changing the oil wt in this fork leg does nothing."

Bull**** to the above statement: Do this experiment: Drain your left fork leg oil, measure it, put in the same amount you took out. BUT put in 2.5 weight fork oil. Go ride!

Drain your left fork leg oil: Measure the amount you took out: Replace it with 15 > 20 weight oil. Go ride!

If you tell me there is no difference in how the bike feels acts rides then you have no business being on a dirt bike let alone a trails bike then you need to stick your head back into your theory books to figure out why!

I give up!

Edited September 30, 2011 by BillyT

[copemech]

Don't be such a Bick, Dilly!

I think he asks some valid questions, trying to get everyone "on page".

I stated(i think)early on that I thought the conventional rod and cone in the left was still handling compression damping(which is minimal, up to a point) in these things, and Livios response seemed to support that theory along with your suggestions.

So, in an effort to get Nif back on the page(if you have not totally p****d him off by now) yes, this is the current understanding, to which I have no way of proving because I cannot put that leg into a suspension dyno, and I am far too lazy to take things apart just to look at them, and put them back, not really knowing WTF I am looking at and with no way of static dynamic testing..

Rebound is easier as I think Livio stated, through feel...

I sell Propane(duh)! Work on Diesel Trucks, and Fast Cars! I have not had time or inclination to experiment here, as stated. I do not really know Dick, but I am doing his sig. other! I am just a dumb farm boy. But in an overview of the proposed theories here that I think I seen and read in this mishmash, I never really seen anything reguarding fixed orface hydro shock/lock, which is in itself a limiting factor in conventional rod/cone compression damping systems. This also explains mid stroke sharp edge impact harshness(high v/s)and is a limiting factor because of hydrolock of the impact. Put simply, you cannot move the fluid that fast through the hole! This may increase with thicker oil, yet reguardless, the factor is still there with any liquid..

Edited October 1, 2011 by copemech

[billyt]

Don't be such a Bick, Dilly!

I think he asks some valid questions, trying to get everyone "on page".

Markus. I will back off on this guy since you and I are OLD friends and I have respect for your technical knowledge.

But this guy is refusing to accept what myself and Livlob is telling him about how the oil in the compression fork leg will affect its compression.

Livlob wrote very succinctly and correctly!

"I'm pretty sure your incorrect about your concept of how the paioli forks work Nif40. I have made many adjustments to change compression speed to the left fork leg by changing oil viscosity in increments of two Cs at a time and i am able to notice each adjustment. It does have a damper rod in it below the spring. I have not yet noticed any compression speed change after adjusting the rebound clicker on top of the right fork leg. In fact if you remove the right fork leg from the bike and loosen the cap so air can enter the fork freely. Compress it and you will not feel any compression resistance. Now extend it and you will feel resistance. I have not had the rebound cartridge apart, but based on my tuning experiances i'm pretty sure it does not control compression speed."

What is it that nif40 is getting us all on the same page on?

Most of us have basic understanding of how the forks on the Beta works.

He is making false statements about Cody webs bike using an after market non Beta shock that American Beta had to correct him on.

And you say I am being a dick?

I think you need to go back and read all the posting better!

My argument is not with you. and when are you going to get that bike out of storage and actual ride @ Munester, Bridgeport, it has been a while since we have saw you actual ride with us?

Take care mon ami!

[rlracer]

This has been fun reading.

Springs for the Beta are available in the U.S. for a round what has been said and those of us on the larger side do need them.

Billy and those who said oil wt. effects compression and rebound yes very much so. Like billy said try both 2.5 and 10-15 wt. oils and go ride the same sections.

I have worked on Cody's bike and what American Beta is telling you is true.

Billy due to work I can only get off one day of Muensters 2 day so I can't justify the 5 hour drive one day. But would very much like to ride with you guys down in Texas.

[steve fracy]

Don't be such a Bick, Dilly!

I think he asks some valid questions, trying to get everyone "on page".

I stated(i think)early on that I thought the conventional rod and cone in the left was still handling compression damping(which is minimal, up to a point) in these things, and Livios response seemed to support that theory along with your suggestions.

So, in an effort to get Nif back on the page(if you have not totally p****d him off by now) yes, this is the current understanding, to which I have no way of proving because I cannot put that leg into a suspension dyno, and I am far too lazy to take things apart just to look at them, and put them back, not really knowing WTF I am looking at and with no way of static dynamic testing..

Rebound is easier as I think Livio stated, through feel...

I sell Propane(duh)! Work on Diesel Trucks, and Fast Cars! I have not had time or inclination to experiment here, as stated. I do not really know Dick, but I am doing his sig. other! I am just a dumb farm boy. But in an overview of the proposed theories here that I think I seen and read in this mishmash, I never really seen anything reguarding fixed orface hydro shock/lock, which is in itself a limiting factor in conventional rod/cone compression damping systems. This also explains mid stroke sharp edge impact harshness(high v/s)and is a limiting factor because of hydrolock of the impact. Put simply, you cannot move the fluid that fast through the hole! This may increase with thicker oil, yet reguardless, the factor is still there with any liquid..

Copey, do you sell Propane and propane accessories??? You are the REAL Hank Hill arent you??

On the fork topic, while I do understand the need to tune suspension to ones specific weight, to say that the stock Paioli is not good in my opinion is not true. I often think that the time spent fiddling around with minor details could be better spent just practising technique. We have been riding the new Evos now for over 2yrs and neither my son or I have had any issues and in fact much prefer it to any Marzocchi fork I have ever tryed.

[billyt]

Copey, do you sell Propane and propane accessories??? You are the REAL Hank Hill arent you??

Good one Steve........ And I vouch that he sounds like Hank Hill, **** they all do down here! LOL

On the fork topic, while I do understand the need to tune suspension to ones specific weight, to say that the stock Paioli is not good in my opinion is not true. I often think that the time spent fiddling around with minor details could be better spent just practising technique. We have been riding the new Evos now for over 2yrs and neither my son or I have had any issues and in fact much prefer it to any Marzocchi fork I have ever tryed.

Good one Steve........ And I vouch that he sounds like Hank Hill, **** they all do down here! LOL

That was my original point Steve. What has the forks on the beta stopped him from doing? Too much time in the theory books and not enough time on the bike honing his technique. Any more earthquakes up there?

Cheers

Edited October 1, 2011 by BillyT

[copemech]

Something for you all to play with--HERE

[copemech]

Steve, I married his daughter! Literally!

Ron, yes, the springs are needed really, and I wish others offered more options!

And yes, Billy, I probably sound like a Texan, as compared to a Scottish Sheepfecker with all them gutteral rumblings and crap you do! Billy IS a good rider, far better than me as I am too old and laid back now. Muenster?

Getting back to forks, I have not disected them, like many here, a non-issue of sorts, but I will not say they could not stand improvement. I am currently wondering about the things now that some things have been said, yet at the same time, I have other projects to attend.

[liviob]

Something for you all to play with--HERE

Thanks for the link Copemech. The Paioli compression fork leg looks very much like the picture. I dont remember seeing The various rebound Parts and passages in the paioli design. It seems that if a large enough diameter damper rod bolt were used a threaded needle could be fitted into it. Turning this needle up behind the compression passages would restrict the flow of oil during compression to effectively create a easily adjustible variable resistance damper rod for the compression cycle and the fork could still maitain it's lightweight and simple design. For trials riding i dont need a fork that is more complicated than this.

As for a compression adjuster on the rear damper. The 01-02 rev3 has one but Beta built the bike around the damper. The EVO dosent have room for this type of damper unless a different airbox were fitted or maybe a damper that looks similar to the Showa design with a seperate chamber wrapped around the outside of the main piston cylinder chamber seperated by an adjustable passage with a nitrogen bladder inside this smaller seperate chamber.

The only practical solution with the current design " unless a damper like the Showa lookalike i described can be found" would be to add a remote resevoir with an adjustable passage to the existing damper and then figure out where to mount it.

[nif40]

Ole man BT didn

[billyt]

Ole man BT didn