Suspension setup

[liviob]

I currently ride a 2009 Beta 290 Evo. I like the bike, but i have had to to make modifications to the suspension beyond simple adjustments that Beta built into the suspension. I have learned by talking to many trials riders that most trials riders dont put too much emphisis on their suspension setup. Most of them seem to only be concerned with adjusting the spring preload and other than rebound speed dont concern themselves much with the action of the hydrolic control thats built into the dampers front and rear. I am far out of the design envelope in terms of physical size "250lbs" and since Beta seemed to have targeted the OEM suspension setup for somone who weighs 160lbs or less I had to install firmer springs front and rear. The springs i installed work very good at holding the chassis at a good ride height for suspension with six inches of travel. With my current "Light" preload settings the chassis will settle 1 1/2" to 2" with me aboard the bike.

Since adding firmer springs I have had to readjust the damping effect because the springs offer more resistance during compression. I guess i could have sent my suspension components off to a shop and had them revalved but I instead chose to adjust damping control by playing with oil viscosity by mixing different viscosity oil's to get the rate of compression feel or control that i am looking for. After many hours of adjusting and testing I can say my suspension works very good for someone my size. It has a bouncy sort of feel and will easily drop into the stroke and offer supplenes without any noticable resistance spikes and still offer me very good bottoming control. I can confidently leap off three foot high ledges without fear of injuring myself or the bike.

The reason i am writing this is because i am curious as to how advanced riders like to setup their suspension. How do you like it to feel for attacking larger more technical obstacals. Do you like a bouncy feel or do you like the dampers to offer some midstroke compression resistance so the suspension will ride a little higher in the stroke and offer a more controled feel during compression?

Edited December 4, 2010 by Liviob

[liviob]

What I'm mostly curious to know is how fast do advanced trials riders like their suspension to compress and with what feel. Do they like the suspension easy to compress or hard to compress. Do they like a very liener bouncy feel until the suspension bottoms or do they like the suspension to offer substantial hydrolic resistance as the suspension gets into the midstroke and beyond to slowup the compression stroke.

[nzralphy]

Most blokes do nothing with their suspension and then go on to say how good it is. Strange really because suspension gets worse with age.

Set the front & rear spring to get 1/3 sag when you stand on the bike. Be accurate with this and get a friend to help set it up. I check this every 6 months(ish) because springs set with age.

There is no law for setting damping settings for your riding style. There are few of rules though......Expensive dampers work much better than your factory shock - sad but true - try one they are great, Dampers and the oil wear out and need rebuilding (if the rebound adjuster has no effect to speed on the shock - it needs a rebuild), Compression damping helps resist bottoming out, Rebound controls the action AND GIVES YOU TRACTION!!!!! (set it fast to do tricks...... and it'll suffer up the hills or in the mud), Roughly set the rebound so it slows the rebound action - then experiment either side of this setting.

[liviob]

Actually the suspension setup i have works pretty good. It works much better than stock. I spent alot of time changing and testing oil centistoke rates after installing new springs of the correct kg for my weight. .71 kg front and .80kg rear. When i ride my bike the suspension feels exactly like Toni Bou's suspension looks in this Toni Bou video.

http://www.photobysergio.fr/video-toni-bou-piera.html

The reason I made this post Is because I recently rode a 2011 EVO 290 and the suspension had a different feel than my 09 EVO. The 2011 definetly has firmer springs than my stock 09 had but it also has firmer compression damping. The 2011 setup makes the bike feel very stable. It also holds the bike up in the stroke better. After riding the 2011 and getting back on my 2009 my modded 09 will drop into the stroke more easily and farther than the 11. My modded 09 feels more supple and it has better bottoming resistance.

As you mentioned my suspension oil needs to be refreshed and I could refresh it to the same spec's as it is now or I could add a few centistokes to the oil viscosity and firm the feel up a little. I was hoping their might be other people who have modded their suspension to get a particular feel of their liking, and be willing to share what suspension feel they like and why they like it. But based on the number of responses I guess I may be one of a minority of people who must modify their suspension to handle their ride weight.

Thanks for the response.

Edited December 9, 2010 by Liviob

[nzralphy]

The 09 were/are very soft and definitely needed heavier springs - perhaps the test riders setting the specs in 09 & 10 were on laxatives? - and that being the case will likely need heavier damping.

A mate was around here fitting a new shock and spring set from TRP, we looked long and hard at the OEM shock and found it was a sealed unit. Unfortunate really cos we were going to have it rebuilt. Nope, it is a POS.

Now the TRP is a whole different world better and the bike rides so much better. I'll get one the same time i order an EVO!

Edited December 9, 2010 by NZRalphy

[liviob]

NZRalphy. I was able to open the stock shock from my 09 EVO. It is very easy to open and service or revalve if you feel the need. You must relieve the internal nitrogen pressure by drilling a hole in the shock body near the mounting lug afterwhich you will tap 1/4 pipe thread and fit a shrader valve. Dont worry about the pressure inside the shock causing a dangerous situation. It may be 150psi or so but it is such a small volume that it only makes a very small sound when it escapes. To open the shock you will need a sharp chisle and gently tap the aluminum dust seal head out of the shock body at the juncture. Slide it up and outa the way. Then with the shock mounted in a vice take two screwdrivers and gently push the seal head down to expose the circlip mounted inside. You have seen the small hole in the side of the shock body near the dust seal. Get a paper clip or somthing strong enough to unseat the circlip thats behind the hole and with a very small flat blade screwdriver that has had the tip bent 90 degrees remove the circlip. Now you can remove the shock shaft. You will find that the shaft will only come out a short distance before stopping against another circlip. You will have to remove it before the shaft will come out all of the way. Be gentle you dont want to scratch the inside surface of the shock body. When you reassemble the shock make sure the floating piston is 84mm from the top of the shock body to the flat part of the piston. If not you will have troubles. I think the oil that is in the shock is Bel-ray 10wt. Here is a chart that assigns centistoke values to each oil. Also there are mixing charts on this link for red line and silkoline oil. I dont recomend mixing oils. they dont stay mixed. Link no work. Send me your email from my personal page and i will send you a copy of an oil cst chart.

If you get a 2011 evo you will not need a replacement shock. The stock suspension is very very good.

Edited November 1, 2011 by Liviob

[atorrini]

Does anyone know exactly where to drill to let the nitrogen out?

[liviob]

There is only one place to drill a hole through the damper body. It's the same place you will find a schrader valve on any damper which has a schrader valve mounted in it from its manufacture. Do not drill through the side of the damper. You will permanantly damage it. If you have never done this sort of thing you may be better off to take the unit to a skilled suspension tech who can perform the service without incident.

[lankydoug]

I'm waiting to hear from some expert riders on this topic. I've adjusted dampening on my shock after installing the correct spring for my 215lb weight and I can make it easy to bounce or very stable with extra dampening. (or anything in between) I too am curious how the good guys set theirs.

[samo]

Can anyone tell please how to measure full sag?

[pindie]

I've been trying to find someone to re build my Rev3 200 shock. Not one person I have been sent links to wants to know. I am tempted in mastering it myself and opening an online rev3 shock service?

To measure/set sag:

1. Wind off all damping so the shock can boing a bit. With you off the bike bounce it up and down by pressing on the seat a few times.

2. Once settled, measure from a fixed point vertically from the axle to the rear mud guard (a dot of permananet marker or tape helps makesure you find the same spot) - write down this number.

3. Put your kit on and get a mate to hold the front of the bike still while you get on and stand in the standing riding position.

4. Get your mate to measure from the axle to the mud guard again.

5. You want this measurement to be no more than a third of the overall suspension travel (approx 150mm at the rear).

6. Loosen the shock spring rings and tighten until when you stand on the bike it settles no more then 50mm ish from the no-rider-on-bike relaxed state.

7. Tighten everything back up that you loosened!!!!

8. Re set the damper rebound until it just takes the edge off the spring return speed.

9. Enjoy!

10. If your about 12-13 stone wind in your fork leg preload by about 4-5 turns from fully out and try 3 clicks in from fully out on the rebound side.

You should find this helps a lot. It will also help shift more weight onto the front tyre which helps balance grip and control a lot.

Edited May 19, 2012 by pindie

[samo]

Thanks Pindie for an answer.

I can not find someone to rebuilt my rear shock too. So let me know when you will start to repair them. I'm

70kg,so I think 2 turns on fork leg preload would be enough.?

[pindie]

Try two as you can always back it off again. You could also try harder and see what you prefer. Remember weight is based upon what you wear on the bike also.

Details on forks are on page 67 of the Rev 3 manual.

[atorrini]

There is only one place to drill a hole through the damper body. It's the same place you will find a schrader valve on any damper which has a schrader valve mounted in it from its manufacture. Do not drill through the side of the damper. You will permanantly damage it. If you have never done this sort of thing you may be better off to take the unit to a skilled suspension tech who can perform the service without incident.

Been riding and working on bikes for 30+ years, but I'll admit that I'm new to trials.

Even though I know my way around, I still look at service manuals before I do a job.

Since I haven't taken a beta shock apart before, I thought it'd be good to ask someone that was in the know.

I didn't think that asking for a precise piece of information deserved such a rude and unhelpful reply.

[liviob]

Been riding and working on bikes for 30+ years, but I'll admit that I'm new to trials.

Even though I know my way around, I still look at service manuals before I do a job.

Since I haven't taken a beta shock apart before, I thought it'd be good to ask someone that was in the know.

I didn't think that asking for a precise piece of information deserved such a rude and unhelpful reply.

I wasnt thinking rudly when i typed out my reply. It still dosent look rude when i read it. If i could post a picture of my modded damper i would, but i cant figure out how to post it. Google is your friend. If you look on the web for a photo of a gas charged damper for a twin shock bike you should be able to see where the schrader valve needs be fit into the damper body. There is only one place you can fit it so the damper internals will not be damaged and so it will clear the yoke of the lower damper linkage and the frame cross member after reinstallation. The damper must be completly filled with oil and well bled of all trapped air.

Please know that i will never intentionaly respond rudly to anyones question and that i have easily invested over $500. in parts and supplys and paying qualifyed suspension techs for their service and knowledge and countless hours figuring out my 09 EVO suspension to get it to work well for a large rider.

This link will take you to a page which will show four dampers. the damper on the left is the best example of where to mount the schrader valve.

http://www.autosport..._car-june08.pdf

Edited May 20, 2012 by Liviob