dr nick Posted January 12, 2004 Report Share Posted January 12, 2004 I`ve heard that a bikes suspension can get soft with age/use ,but mine seems to to be stiff compared to other bikes. I`m going to change the fork oil in the front for a recomended brand to see if that makes a difference...but not sure what to do about the back. Anyone got any ideas regards N Quote Link to comment Share on other sites More sharing options...
ronm Posted January 13, 2004 Report Share Posted January 13, 2004 (edited) Hey Doc, It would be easier if you said what model bike you have, but in general: Your forks could have gotten stiff because of air build up. Air can leak in past the seals on the rebound stroke and then can't get out. Most bikes have a small bled screw in the top cap. If you find one, loosen it and see if air escapes. Other than that you generally run SAE 5 fork oil. Several manuals recommend Belray. I have used that, Maxima, Spectro, and Honda brands. All work well. You did not mention whether the changes have happened while you owned the bike. It is possible that a prior owner used the wrong grade or put in too much. The proper level is very important. As for the rear, the only way I can think of for the rear to get stiffer is some kind of mechanical binding such as a bent shock, etc. Some shocks are not rebuildable (although any shock can be opened and rebuilt if you are clever and have the equipment). I have not rebuilt a Beta shock yet, so I can't help you there. Paoli has a web site. You might check it out or call your dealer. I Hope this helps. Edited January 13, 2004 by RonM Quote Link to comment Share on other sites More sharing options...
dr nick Posted January 13, 2004 Author Report Share Posted January 13, 2004 for the 2nd time today you`ve been very helpful Ron My bike is a 98 Techno....it seems (so I`ve found out recentlyfrom a friend) that its been like that from when I got it. I`ll check the bleed screw 1st....then change the fork oil on the front but I will make do with the back for now regards N Quote Link to comment Share on other sites More sharing options...
billyt Posted January 14, 2004 Report Share Posted January 14, 2004 Dr Nick and to all Keep in mind that most trials forks are usualy broken in to the following: One fork for compression One for rebound. What tends to happen is that a rider thinks his supension is to soft or bottoming out on the compression so adds heaver oil to both forks. What he does not take into consideration is that the rebound will also be slowed down by this heaver oil. One can use two different weights oils for each fork. I personaly use a 2 1/2 weight on the rebound side and a 5 weight on the compression side. This way it does not bottom out and also returns briskly without a pogo effect either. BillyT Quote Link to comment Share on other sites More sharing options...
dr nick Posted January 14, 2004 Author Report Share Posted January 14, 2004 just got back from my local bike shop.They recommended 2.5 wt fork oil both sides ,so have bought some. I`m going to try the 2.5 wt oil in both forks...if it works ok I will stick with it ...if not then I will try Billy Ts idea .... Billy ......BTW how do you tell which is compression and which is rebound side of the forks. regards N Quote Link to comment Share on other sites More sharing options...
ronm Posted January 14, 2004 Report Share Posted January 14, 2004 On the Paolis on your Techno, the adjustment on the right leg is for rebound damping. The adjustment on the left side is for the spring preload. You have to change oil in the left leg to change compression damping. The Beta manual recommended 5 w oil in both sides and that is what I used in my '96 Techno with good results. -Ron Quote Link to comment Share on other sites More sharing options...
dr nick Posted January 14, 2004 Author Report Share Posted January 14, 2004 thanks Ron....but what will using 2.5 wt oil do to my suspension.Will it make much difference? Regards N Quote Link to comment Share on other sites More sharing options...
billyt Posted January 14, 2004 Report Share Posted January 14, 2004 (edited) Dr Nick One can not simply say what is right for you they can only offer a starting point from which you can experiment from. Think of the fork oil weights as another tuning tool. The oil weight that you do end up with should allow/afford you the ability to have the suspension dial/controls set in the middle of their adjustment, this way you can fine tune them for terrain and slight weather conditions on the day. To really appreciate what I am saying, drain the oil out of the return side/rebound. and go for a short test ride. The bike should still be somewhat controlled on the compression stroke but should fly up out of control on the rebound stroke. This allows you to feel what ligher oils can do, you the can fine tune to taste. You will not feel a big difference from the same weight of oils in the forks as you would going to extremes, meaning you would really notice a change in say 20 on the comp side and 2.5 than you would 2.5 on both sides as oppessed to 5 on both sides. I have had riders in the past use as much as 15 weight in the compression side and 2.5 on the rebound. And one rider with 20 weight in each leg. A lot depends upon your riding style (how agressive you are, like how big are the rocks or ledges you are dropping off) your body weight and the climatic conditions you live in. Just like in your cars engine oil a colder climate will see the heaver oils get really stiff and lethargic on you, were as a light weight oil will get very thin in very hot Arizone/Texas summer weather. I had riders change the fork oil weight seasonaly I would recommend you always use a lighter oil in the rebound side, but only you can be the final judge in how it suits you and your riding skills. For example guys that like to hop like bunnies in the section use very light rebound oils with high spring rates. One of the reason Beta recommends the same weight oil is that it is easier to ship the bike out that way as it means they do not have to keep two inventories of oils and maybe even get them mixed up in production, but also they do not know were the particular bike will end up in the world ie climate/weather how much the rider will way etc riding skills. I would start with 2.5 in the rebound and 5 weight in the compression side. BillyT Edited January 14, 2004 by BillyT Quote Link to comment Share on other sites More sharing options...
dr nick Posted January 14, 2004 Author Report Share Posted January 14, 2004 A very in depth explanation ...and thankyou for taking the time to write it out.It really helps explain it all to me a bit better now Regards N Quote Link to comment Share on other sites More sharing options...
dr nick Posted January 16, 2004 Author Report Share Posted January 16, 2004 I`ve just finished changing my fork oil and put everything back together. The instructions in the photo copy manual I have are very basic. I had trouble screwing the screw back in at the bottom of the l/h leg(it wouldnt catch in the threads) I had to take the fork out of the clamps to sort it out. Anyway ...its all back together now,but I`m a bit stuck about how to get the air out of the forks. It says in the manual to ...compress the forks a few times ...then let the air out by undoing the nuts at the top. Does this mean that I have to get "all" the air out of both forks by pushing down on them and tightening the nuts up at the top before releasing them again. It could be because its a bit late and I`m tired so things seem a lot harder to understand and the manual is straight forward ,but I`m just not getting it. It basically says to undo top nut....undo bottom nut....drain oil...tighten bottom nut ...fill with 360cc`s of oil ...tighten top nut...pump forks as there will be no load on them...then release top nut to release air. I have done all the above but the forks are as stiff as hell any help greatly appreciated regards N Quote Link to comment Share on other sites More sharing options...
ronm Posted January 16, 2004 Report Share Posted January 16, 2004 Hi Doc, I think the 360 cc number is for when you can get the forks totally empty, which I suspect you can't do by draining them on the bike. I think it is better and easier to take them off and turn upside down to drain. Some oil will remain in the damping components, and you will need to pump the tube in and out a number of times to get it all out. When you fill it back up, forget about using the specified volume. What you want to do is fill them up to the specified distance from the top of the tube. This spec should be in your manual. I don't remember the number. You will need to pour some in, pump it in and out until the air is displaced, and continue filling. You need to make sure there is no trapped air below the oil level. Otherwise, it will free up later and your fork will be too soft. Be sure you follow the instruction as to whether the number of mm belot the top is with the spring in the tube. After you get them back on, you can pump them up and down a few times and release any excess air if you want. I have never bothered. But if you do, you will do it with the forks extended. Hope this helps. Quote Link to comment Share on other sites More sharing options...
dr nick Posted January 17, 2004 Author Report Share Posted January 17, 2004 I have checked the manual over and over ,but it doesnt give a figure for specified distance from the top of the fork...just the 360cc volume. Anybody out there now what the distance is ? Forks feel better ...but I think I need to check if there is any air in them. I have been meddling with the 2 adjusters at the top of each fork leg,I think I know what the one on the compression side does (L/H fork) it compresses the spring to give stiffer suspension..but cant see what the adjuster on the R/H side does. While I was at it ,I changed the wheel bearings front and back ,fitted a new chain and changed the gear oil while the bike was stood on my new workstand (see other topic) ....funny thing is ...the little check window isnt showing as much oil in it as there was in before ( its just about shownig that there is some)after me putting the (manual) specified amount of oil in (500cc).I might as well throw this manual in the bloody bin for what good it is Anyone out there know how much I should put in ? I`m still on a very large learning curve ,so ,any help is greatly appreciated regards N Quote Link to comment Share on other sites More sharing options...
beta boy Posted January 17, 2004 Report Share Posted January 17, 2004 the standard amount of regular gear oil is 550cc Quote Link to comment Share on other sites More sharing options...
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