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My 09 290 EVO uses the BR7ES plug. Maybe four months ago i changed the plug for the first time since new due to a rough runing low rpm range. After inspection of the plug i noticed that it was begining to foul due to oil contamination. The engine ran like new with the new plug. It is begining to run rough again at low rpm. I used to run the standard plug gap which i think is .024-.026? Im not sure at the moment unless i go look at the owners manual. A freind recomended that i set the plug gap to .020 for better bottom torque. Im thinking that this smaller gap setting is causing the plug to foul. It's the only thing that i have changed in the combustion process. What do you think? Do any of you have exeriance experimenting with plug gap. I plan on installing a new pug set to the standard plug gap.

approxamatly 30% of total wheel travel.

I installed the head gasket on my 01 rev3 250 dry, and im pretty sure the small holes were to the front.

Quiet, be vewy quiet. Do you hear dat? It's the sound your bike makes when its twying to tell you it needs a new intake manifowd.

Sure.

The last carb settings that i mentioned work great in the sections. I am very amazed by the amount of smooth power the 250 makes. I did remove the clutch side flywheel and add a v-force3 reed to the engine and it did respond by producing a little more torque.

Thanks for the reply Steve. I would be interested in looking at the Costa foot rests but I am looking for stronger footrest mounts.

Anyone know of an aftermarket source for sturdyer footpeg hangers for the 00-06 Rev3 bikes. I think these stock Beta hangers bend under my own body weight, and if i bump a rock with the peg their bent for sure.

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.

Nice Video. Thanks

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.

Yes that seems logical, this setup may not work that way though since there is no check valve at the top of the damper rod allowing the rebound cartridge to perform extension control. What do you weigh and what bike are you talking about when you describe harshness. The 2011 EVO has a spike in the middle of the suspension travel. For my weight its not an issue, but for a rider under 200lbs it could be a concern. I think the reason a rider may experiance harsness during the compression stroke is because the manufactures have to try to fit the bike to a large range of rider weights. To accomplish this they use light spring resistance and try to control piston velocity and bottoming with firm hydrolic control. If they were to use much firmer springs and faster low speed valving and slower high speed valving there would be less issues with harshness. The springs that i am using could easily work for a 150lb rider if less preload were used and faster oil were installed. I think my current setup with the worn out oil would easily accomidate a 160lb rider. I think a 160lb rider would like the bouncy feel it has.

Thanks for the info 0007. I am going to ride it this saturday. It's running pretty strong with the new carb setting. I think the ignition timing is set to stock specks. It's not as torquey feeling as my 290, but its not far off from it either.

Nice ride and video! Is your clubman line equivelent to amature or intermediate?

All clutch baskets that i have inspected seem to move a small amount. My 01 Rev3 250 and my 09 EVO 290 both have a rattle sound at idle and when the clutch is disengaged at idle it will quiet some. I'not certain without seeing the bike if this is your bikes issue.

Since Beta supplied the 09 290 evo with suspension springs for a rider weight of 125Lbs. or less i had to find the correct resistance spring set for my 255 Lbs. body weight. MCR suspension was able to build me a set of springs. The front spring is a .71kg and the rear is a .80kg straight rate spring. With these springs i can get the correct ride sag number of 2" with less than 8mm of preload added to the springs. The stock springs are front .61kg and rear .56/.60kg. Theres quite a difference in spring resistance. I couldnt dial in enough preload with the stock springs to get the suspension to work right. Using factory supplied hydrolic control settings these firmer springs require the use of faster oil or oil of a lower centistoke rate or the suspension will feel too firm on compression stroke. I'm not sure what 5wt. oil paioli supplied the forks with but i am using Redline 5wt in the rebound leg because thats whats on my shelf after previous experiments and i am using Bel-Ray HVI 3wt in the compression leg. It has a Cs value of 11. Both forks are set to factory oil level heights. The preload adjuster is now set to 2 1/4 turns in from full out. When i first opened the rear damper it had a thick blue oil in it which i have yet to identify. I'm pretty sure it was a ten Wt oil. In the rear damper i am now using Maxima 165-155 fork fluid because it has a Cs value of 32. This is a cs value in the lower range of the 10wt oils. I have the spring preload set at eight turns in from the moment the adjuster collar touches the spring. For a rider weight of 180lbs and up to maybe 230lbs this setup will provide a very plush initial travel and smoothly firming up to very good bottoming resistance. Minor preload sdjustments can be made for different rider weights as can oil Cs changes. This suspension change will make the 09 EVO feel much more stable. I like to set the chassis a little bit lower in the rear. This slows the steering some and allows the very steep downhills to feel safer. I started out using much less preload. I have noticed that these springs have settled many times since new. When i service the suspension again I will keep the same preload settings and switch to a higher Cs value oil front and rear for a firmer compression feel. I do agree with Nif40's initial complaint. It would make tuning much easeyer if the compression fork had an external adjuster and the rear damper had a compression speed adjuster added.

After riding the bike again i decided that the carburator was still set a little lean. I did install a #150 main and i also decided to increase the pilot jet size to a #35. This change made a very noticable increase in bottom end torque and bottom end snap. The motor also pulls thru the middle and upper rpm range much stronger. I also had to reset the airscrew to two turns out from 1.5 turns out. These 250cc Beta motors are nice running motors. They are very easy to control.

The clutch mod is a worthy investment of your time. The clutch will ne smoother and more precise. As for the kit "Quicker, smoother and more precise working. Reduces chattering on high revs."

Which year EVO do you have Nif40 mine is an 09. I will be taking my suspension apart within the week for service and tuning adjustments. I'll take pic's and post them if i can post them. If you have an 09 i have a setup that i think you will like.

Anyone know of video coverage for the 2011 TDN?

Great! Look forward to hear about what you find. I will be leaving tomarrow to a trial in the mountains and will probobly not be able to look at this again until next monday.

Thanks for the link Carl. Even if the factory guys are using paioli forks the internals could be very different from what we get. I was talking with a freind of mine who tunes race bikes for a living and he said that it would probobly be possible to install inyards from a motocross mini bike which would have a tunable base valve into these paioli forks.

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.

Honestly i like the Paioli setup. Once i learned how to adjust them i find them very easy to tune. All of the compression control is done on one fork and all of the rebound is controlled on the other fork. The Paioli fork and shock are both very good quality and very adjustable. Unfortunately as supplied from Beta they are not setup properly for an average to large size adult male rider. The fork is a little easyer to adjust by changing the spring and oil viscositys, and oil level. The shock can easily be opened and it has tunable shim stacks on the piston you can alter. You can also change the spring for your ride weight. I have been changing oil viscositys in the shock to alter compression feel with excellent results and as you know there is a rebound speed asdjuster on the shock. A good suspension shop can get you the springs you will need. They can also get you rebuild parts. Here is a link to the instructions to opening the shock. http://www.trialscentral.com/forums/topic/33584-suspension-setup/page__pid__254486#entry254486