dan williams

The riders are young, the logistics are impossible and the sections are way over the heads of most. Still a bunch of kids from the US went out and rode on the international stage and were ambassadors for American trials. They don't travel in luxury. They are sometimes given less then their due by the arrogant even from their own country. I'm proud of them. I've met all of them and they're great kids. I can't think of better representatives for who we, as American trials riders, really are. Whether you believe it or not they have the respect and friendship of the top riders. The TdN is that rare event at the top levels of any sport where the pressure is off and all the riders mix like experts and novices at any local event. If you don't think Tony Bou or Adam Raga cringe when they see a young rider crash you haven't spent enough time with a top rider. They are hyper competitive by profession but they're good people and they know what it's like. This isn't a "rah rah Go America" rant. It's a, "Have a little common sense and show a little respect" rant. I was always amazed at how much crap the Wickers put up with but they just kept putting the effort into getting the team there. Now Kip is the man doing the thankless job. Thanks Kip for stepping up when others are content to sit on their asses and throw rocks.

My apologies. Only bike I had with a DelOrto '95 Beta ran much better with a swap to a Mikuni.

Ouch. Nice kid. Hope he's OK.

...and go Kip! Nice work getting a major sponsor. Missed you up in VT.

The screw sticking out the side is idle speed adjust. It determines where the slide stops at the bottom of it's travel. The other screw is the pilot mixture adjust screw. DelOrto's are different then Mikuni or Keihin in that this screw adjusts fuel where on the other carbs it is an air adjust. For the DelOrto, screw in (clockwise) equals leaner mixture. For the Mikuni/Keihin, screw in (clockwise) equals richer mixture. Typically 1.5 to 2 turns out from bottoming out is standard. This will affect how the bike responds off idle. Can't give you more then that as every bike is different so you just have to fiddle with it 'till it's good. Lean mixture will cause a "hunting" idle speed and a bog off idle when the throttle is pulled open quickly as well as pinging off idle or shutting down. Rich will run somewhat lethargic from idle to 1/4 throttle, will smoke a bit more but will start easier with the choke off when cold. Beta's also tend to run rich when pointed downhill because of the carb mounting angle which is made a bit worse with a misadjusted pilot circuit.

To the best of my knowledge that is the only significant difference with Sureflex and what got me started on this issue. The 30X series of Fantics came with Sureflex plates and their clutches were excellent.

Yup the washers keep the bolts from digging the coils as well as making it all line up. The rope in the cylinder trick is OK I suppose but it still applys twisting torque to one side of the crank plus it adds possible contaminents to the combustion chamber.

Working on a friend's bike I was concerned his flywheel key may have sheared so I removed the flywheel (key was fine) now how to re-install? Holding the bike in gear with the back brake locked is not an option. Not only can you not get enough torque on the nut you risk damaging the crank by applying twisting force to it. After scheming various machined and welded special tools I realized I was over thinking it. $6 worth of bar stock, four holes, three bolts, a wing nut, couple of washers and one hacksaw cut later...Voila! The Beta flywheel holding tool. Works like a charm. http://newenglandtrials.org/flywheel_tool.jpg

You know when you're in a rush at the end of the day and you shift into 2nd for some twisty climby section and realize five feet into the section you're in 3rd and there's no good place to shift so you just ride it? Well with the Vforce reeds the bike will just pull you through without a sputter. I can honestly pull a gear higher at low RPM with the Vforce. I did talk to one guy at the national this weekend who put Vforce in his EVO. His comment was, "I don't know if I can stall the thing now. With the stock reeds I was stalling all over the place." That pretty much sums up my experiance with the Vforce on my '05 and '08 Rev3. Luv 'em. I can't speak to the Boyesens as I have no experiance with them but I assume it is similar. The idea being a reed with less mass can react to changes in air pressure quicker so they maintain a higher crankcase pressure which means more power at low RPM. Effect at top end for the trials application is almost moot since the bike is making more power then 90% can use anyway.

Take a jeweler's file or an ignition file and remove the adhesive between the fiber pads on the fiber plates. Then look at the tabs on the fiber plates that ride in the grooves in the clutch basket. These are usually unfinished and are the cause of most of the Beta clutch problems. Essentially these are bearing surfaces and when the clutch must engage or disengage these have to slide in the groove of the clutch basket. This is what the plates look like from the factory. http://newenglandtrials.org/clutch001.jpg http://newenglandtrials.org/clutch003.jpg Needless to say this is less then ideal as a sliding surface. Imagine as the clutch is engaged these surfaces are torqued against the side of the clutch basket grooves and stick. This makes the clutch slip until the lever is released further and the plates let loose with a snap. AKA light switch clutch. Also why the Beta seems to have a heavy clutch. The heavy springs are there to compensate for the inability of the fiber plates to slide by forcing them into position. Now look at it from the disengagement side. The lever is pulled in but the plates are held in place by the torque forcing the rough surfaces on the tabs into the basket grooves not allowing the plates to slide apart to release the clutch. This is the famous Beta dragging clutch. Take a fine file and smooth the sides of the fiber plate tabs trying to keep them even with each other so they all contact the bearing surfaces of the clutch basket. This removes the rough edges. Finish with a polishing stone. It's OK if it rounds them somewhat. I've done this on several bikes and the result is a Beta clutch that is smooth and consistant. One of these days I have to write up a good description of the procedure but for now this will have to do. On my bike with the fiber plates cleaned up and two springs removed I have no slip and a light clutch pull that is on par with any bike I've ever ridden. It's a time consuming fix to do but it's free and it works like a charm.

V-force,no jetting changes just bolt them in and ride. As for the differences in the Betas over the years that's almost impossible to quantify. Beta tends to oscillate between clubman bike and expert bike. The situation the 270/250 was meant to address I believe. The big difference with the primary side flywheel weight is the same as adding any other flywheel weight. The bike won't rev as quickly with the weight and more energy is stored in the rotating mass whith the flywheel. What this means in practical terms is an engine with more flywheel will be less jumpy with the throttle in tight rolly rocks but also slower to respond when instant power is called for. When riding steep hills with the '08 270 a burst of throttle will lift the front end for the transition and the throttle must be held above a certain setting. Bump on the way requires a flick of the wrist to load and unload the suspension. The '05 with the extra flywheel is a little different. Starting at the bottom of a climb I'd rev the engine to store energy and dump the clutch to release it into the rear wheel. Similar acceleration but different techniques. At the top of the climb with the extra flywheel you just roll off the throttle and the bike finishes with the stored energy in the flywheel. Do the same thing on the bike with less flywheel and the result is usually a stall just before you're successfully on top of the obstacle. It's not all bad with less flywheel though as the more responsive engine lets you make corrections you can't make on the heavy flywheel bike. Having ridden both I can honestly say I prefer the less flywheel/quicker engine but it really has to be running right or it can be a real handful.

From '00 to '06 Beta had a primary side flywheel on the 270 and not on the 250. In '07-'08 the 250 received the primary side flywheel and the 270 didn't. The '08 has a Keihin carb that absolutely must be kept clean. It is much more sensitive to environment and if it gets a bubble of water in it's pilot circuit the bike will run awful down low. It won't evaporate either. It has to be disassembled and blown out. On my '08 270 the bike also comes stock with the fast throttle tube (white) I don't know if this is the same for the 250 but earlier bikes came stock with the slow throttle. I also went down one tooth on the countershaft sprocket whick made the bike much easier to control at slow speeds. Another big help was the use of V-force carbon reeds. The tractor torque added by the carb0n reeds helps make the bike a real trouper when I screw up at low RPM. There are a couple of other fixes I've posted about earlier including a clutch fix that cures the grabbiness/slip problems and a fix for the electrical gremlins. I think I should document the clutch fix better though. I'll work on it.

Apparently not but when I get an EVO it's the first thing I'll add. The difference in my 05 & 08 was immense.

and I was annoyed at a little dent in my Akropovic pipe last weekend. You guys put it in perspective. Thanks.

Only covered the top five pros. One camera shoot. Nice to have but obviously low budget.

I don't know who this gentleman is but I'd love to sit down with him for a chat. Charming fellow.

The problem is these tubes are meant to be atmospheric vents for the float bowl. Occasionally fuel will get splashed up into the tubes and because the ends of the tubes are below the fuel in the float bowl they act as siphons. If you cut a small hole in the tubes above the float bowl say about halfway up the carb body they won't act as siphons. An easy cheap fix. Can't beat free.

Hi Tony, Here's a google maps link that will show you exactly the field the event is at. http://maps.google.com/maps?q=http:%2F%2Fb...p;hl=en&z=7 The venue is Highgate VT

Hi Tony, Sorry I can't help you as I'm going up both days to work but I can post a link to this thread on the NETA web site and see if anyone's available. Dan

Hi Kip, Posted your message on the NETA site. http://www.newenglandtrials.org Hope to see you up in Vt Dan

OK two different systems here. The two tubes that come out the side of the carb are atmospheric vents. They are never meant to see fuel, only to keep the air pressure above the fuel in the float bowl at ambient. In some cases fuel will get splashed up into these vents and because the tubes attached to them are too long and end below the float bowl they act as siphons and will drain the tank if left unchecked. There are a few solutions to this. Raise the end of the tubes so they are higher then the float bowl or drill a couple of extra vent holes into the bowl or cut a hole in the vent tubes above the float bowl. The single brass tube that comes out of the bottom of the float bowl is the overflow. If the fuel level in the float bowl gets too high this is where the excess leaks out. This indicates either a damaged float (sinks to bottom of bowl so never shuts off fuel supply), a damaged float valve (check valve and seat, both can be replaced on Mikuni), the float level is set too high or a float is binding on something usually the float bowl gasket. Since you say it's coming out the overflow on the bottom of the float bowl I'd pull the carb and check the valve seat for dirt and make sure the seat is clean and smooth and the rubber tip of the valve isn't damaged. Next check to see if there is any fuel that has leaked into the floats. There should be nothing in the floats but air and no damage should be visible on the floats. Re-assemble the floats and move them through their travel and look to see if they could be binding on anything. If they are do what you must to get them moving freely with out interference. It's possible that they may not show a problem with the float bowl off so look to see any potential rubbing spots and take an X-acto to them if its the gasket or file a little bit if aluminum. A quick check (though it spills fuel) is to reconnect the fuel line with the float assembly together and turn on the tap while holding the floats closed. if no fuel leaks out the valve is working.

Clutch plate wear usually just shows as slipping. Wear of the hydraulics usually shows up as inconsistancy of the actuation. Trials clutches do tend to actuate fairly far out since they try to make the pull lighter by having a longer lever throw then an enduro bike.

No you're not confused. I'm an idiot. Got it backwards and as punishment I'll leave it there for all to enjoy. Only excuse it was past my bedtime.

It's not really the oil that provides the seal. It helps certainly but mainly it's the pressure above the ring that does the magic. The high pressure above and behind the ring force it into the cylinder wall and seat of the ring groove. When you're spinning the engine by hand there's a lot less pressure so the seal isn't as good plus there's a lot less time for air to leak at running speed.

The throw on a trials clutch is very short which means the range for adjustment is very small and any minor issue with the system can really mess up the works. Forgive me if this seems too simple. I'm not trying to insult. One thing I learned as a tech writer is start at the very basics as more advanced readers can skip over but novices need to be given enough info to get started. OK to make sure we're on the same page here. Is the clutch slipping when it is fully disengaged? Is the clutch dragging when it is fully pulled in? All I can understand from your post is that the engagement point is too far out. Fair enough. There are two adjustments on the lever. The first is the stud type screw that is in-line with the master cylinder piston. This screw adjusts the engagement point of the clutch. Screw it in towards the master cylinder and the clutch engagement point moves closer to the grip. Once that's adjusted to taste the lever stop screw that determines where the lever sits at rest must be adjusted out far enough to let the master cylinder piston come all the way out. That's pretty much it for adjustment. There is one other adjustment that is often forgotten and that is the position of the lever perch on the handlebar. Most trials guys run this fairly far from the grip to get more leverage. There have been reported instances of things like water being absorbed by hydraulic fluid and improperly drilled master cylinders but that sort of thing is extremely rare. Aside from assembly issues like leaving the ball bearing out that acts as a bearing for the push rod there's not that much to it. It helps to have the documentation, motor http://www.betamotor.com/system/attachment...t_04_motore.pdf chassis http://www.betamotor.com/system/attachment...0cc_veicolo.pdf On my last two Betas I've done a modification to the clutch fiber plates where I take them out and clean off the excess glue between the fiber blocks and smooth and polish the sides of the tabs. This makes a world of difference in the behavior of the Beta clutch. Details here. http://www.trialscentral.com/forums/index....15689&st=0# That's all I can think of at the moment.