dan williams

Unless you've ridden the thing almost every day it would be unusual to wear a clutch so far it needs a full replacement after only four years. Can you tell us what the symptoms are? As pointed out, if the clutch is slipping or dragging it's possible you have the lever adjuster in too far so the reservior port isn't being uncovered at the end of the lever stroke. This causes the hydraulic system to be a "closed" system where either not enough fluid is in the system to completely disengage the clutch or the fluid heats up, expands and causes the clutch to never fully engage. Look at the master cylinder with the lever not pulled in. If the piston has not come back all the way to the snap ring you either have to back the screw out that pushes against the piston or you have to back out the screw that acts as a lever stop to allow the piston to come all the way back in the cylinder. It is also possible to have a weakened spring in the master cylinder due to a crash that smashes the lever in too far. The comment about clutch pack height and fingers and such is true for a "new style" Gas Gas clutch but not the Beta.

The reed are held closed by the back pressure from the downstroke. It's not that significant if there is a little space at the tip at rest. If you put light pressure on it and it sits flat against the seat it should be fine. Also the air leaking past the rings, if you are turning it by hand is normal. If you pull the cylinder and see significant blowby on the piston then it's time for set of rings.

I'm not saying you've done this Hugh but if you're three keys in then... It's been said before and I'll say it again, it's virtually impossible to hold the flywheel tight enough to put the flywheel nut on by any method that includes holding the back wheel. Not to mention that it puts tremendous twisting torque on the crank. A proper flywheel tool is the best and safest bet. A lot of guys in the know use air drivers which I suppose do the job but I'd be more comfortable with a holding tool and a torque wrench. This comes down to do it right or do it over. A sheared key could throw your timing off enough to scorch the valves. Hmmm.

When I was a poor teenager I'd bead blast them at the machine shop I worked at. Seriously though given the cost of everything else on a trials bike the plugs are the cheapest thing on the bike. Easiest to just buy new.

Yup, running backwards is an indication of the timing being way off. Check it with a timing light first. Takes a little jury rigging connecting to a car battery but it can be done. Make sure the timing is advancing with increase in RPM and that it is in the correct place. Make sure ground connections and all are good. Make sure all connections are the right way round. I had an Armstrong that ran backwards, over heated and generally ran bad. Turned out the trigger and charge wire from the stator was reversed so it was retarding the ignition when it should have been advancing. Took two years to find that one. Be a shame to spend

70:1 - 100:1 with a full synthetic is typical on a trials engine. Anything more and you'll be replacing muffler packing every few months and having to rev the motor before each climb to clean the goo out. Maybe 50:1 if you plan on running an enduro flat out on the thing. After 20 years of running at between 80:1-100:1 I've never had an engine failure. After about three years I'll change rings but that's pretty much it. Every time I've opened a trials engine I'm amazed at how little wear there is on the top end. I also notice, even when run at 100:1, there's always residual oil on the bottom of the crank. I've run Spectro, Mobil 2T, Belray MC1, Melray HR1, IPONE. So far the bikes just don't really care as long as the jetting is correct. I think compared to a road race engine there's a lot of time for the oil to stick to the parts so the mixture can be a lot less saturated. At 35:1 you'll be the guy with the smokey bad running bike. People will think you've blown a seal.

Check out the ratings on a site called dpreview. They really do test the cameras pretty throughly. The Panasonic Lumix are highly rated as are the Canon G series. A lot depends on how much you want to spend and how proficient your dad is. Some great shots can be taken with very inexpensive cameras but it's easier to really push it with a more advanced camera that lets you manually set F-stop, shutter and exposure.

Membership? Site supporter? I've seen this mentioned several times and noticed it on some people's sig but nobody ever says how to do it and how much. It's a classic case of assuming the other guy knows what you know. If you make people dig for information they won't. Andy?

No big secret. I own the website for newenglandtrials.org so I have my own server space. Once Stu EMAIL'd the pics to me I FTP'd them to my server and put a pointer here to the pics. The pointer is basically a set of HTML tags that say "<img> picture address here </img>". The tags tell your browser that the address points to a graphic so treat it as such and the picture address is the file location on the web accessable server. Essentially the pictures have to be on a computer somewhere the internet can access them. A "server". When you put them up on flicker or some other picture server you're throwing them up on a server that is open to the internet. I don't know if Andy has any setup for uploading to his servers. It's a real pain to maintain if it is and I can understand limiting the access. Disk space can be eaten up fast by photos and there are serious consequences if a server you're responsible for gets loaded with, er... shall we say questionable material. Best to just rely on the photo sharing sites to hold content as they are equipped to handle such issues.

They have a web site but I can't remember where I saw it. Took some digging and it really said nothing. I think they don't do the trials helmets anymore. Pity as I really liked mine.

I don't know 10-15lbs. Hurt a lot. That's odd clutch behavior. Requiring more pressure to statically hold in is just wrong. Once it

Beta's like high grade fuel but if it runs good down low and sputters on top the it's probably time to pull the carb for a good cleaning. Complete disassemble and blow out with compressed air. Also might be time to repack the silencer.

Point taken. Just as a side note it takes about 6 amps to start the fan motor so if you try to spin it up it takes a beefy supply.

Helping out Stu with posting pictures. a bit odd for sure. What kind of oil is used in the bike at what ratio? Did it sit unused for a long time? The reeds on one side definately look more abused then the other. What does the inside of the cage look look like? It almost looks like one side isn't opening so it isn't getting cooled by the incoming mixture.

With engine running, short the thermostat switch. Fan should come on. If not a new fan is probably in order. 70:1 - 100:1 common oil ratio with good synthetic. Racing fuel is best because the bike won't tolerate marginal pump fuel at all well. ATF in a Beta tranny makes the clutch very abrupt. I prefer any of the good synthetic gear oils like Spectro Golden Gear or Honda HP.

I run Delco #4 platinum plug in my '05 but you have to change the plug cap as the tip isn't threaded. The resistor is there to limit the rise time of the spark for radio interference. There is usually a 5kOhm resistor in the plug cap as well. 100:1 BelRay MC1, VP C-12 fuel. Spectro Golden Gear in the tranny. ATF makes the clutch grabby.

I put carbon fiber reeds in my bikes now so I have a set of the stock reeds and cage rattling around in my truck somewhere. I'll try to find them and have a look but I seem to remember in the back of my little mind that there was what looked like overspray of black paint on mine to some extent. On the old piston port MX bikes and certainly highly tuned road race bikes a back fire through the carb was possible but the port timing on a trials bike is so conservative that I'm not sure it's even possible and if the timing was off that much it's a pretty safe bet the thing wouldn't run at all. I've seen a lot of things but I can't think of anything that would cause the reeds to be scorched in a trials engine. Then again I'm always learning new things. Maybe if the engine was getting super hot because it was lean from a blocked jet or something but it would have to be spinning over very fast with a light load to sustain combustion. Odds are it would seize very quickly. I keep running it over in my head but I'm drawing a blank. Wish I had your reeds here to throw under a microscope. Did you buy the bike new or second hand?

Huh? No the reeds should not look scorched. There should be no flame front going back to the carb. If there is your timing is waaaay off. Even then I'm not sure it's possible as the mixture is under very little pressure when the transfer ports are open. OK first things first. If the bike runs good at low RPM that's where the reeds are working. At higher RPM the reeds just stick open so it isn't a reed problem. Look for a blockage in the main or needle jet. If they're clean you may have a blockage in the exhaust system. Barring that it may be a high resistance breakdown in the ignition that only occurs when the engine spins up and can generate a high enough voltage to break down a dielectric but that's very unlikely but try a new plug and make sure your wires are not resting against the head or frame. You need four things. Ignition, fuel, air, compression. If it's running at low RPM you have compression. If it keeps running, though badly, you have ignition and the only question there is do you have the right timing? You say your airbox is good so that just leaves breathing out the other end. Most likely culprit is fuel. Blocked jets, blocked fuel tank vent, bad fuel, blocked float bowl vents, bad float/valve, blocked fuel filter. I'm still leaning towards blocked main/needle jet. Remember just because the jet looks clean it doesn't mean the bleed air passages in the body are clear. Get in there and blow them out with compressed air.

2000 was red and silver. Only Rev three with upside down forks. 2001 was blue and yellow

My clutch felt heavy today but that's just from not using it for four months of winter. Felt good to be back on the bike. Didn't even crash. Unfortunately I just walked into a weight the girlfriend left in the middle of the floor and think I broke a toe but hey I got 9 more where that came from. Grrrrr.

Gotta be a little more specific about the symptom. Is it harder to pull in the clutch? Does it require more pressure to hold the clutch in once it's pulled in? Does the clutch seem to return slower once let out? If the clutch is pulled in slowly does it require more pressure then before? Basically the questions are to identify if it's a case where there's more friction in the mechanism. i.e. something binding like the throw rod or a seal has swelled or one of the cylinders has scored. Or something like water in the fluid or the wrong fluid. Scientific method. Observe and analyze. Once we have more info we can start taking pot shots at an answer. Of course I have a particular favorite clutch mod of my own but that's been flogged to death here so I won't go into it.

I've posted this before and I know it's not the UK but... A friend had a custom spring wound by Cannon Racecraft in Oklahoma for the rear of his 2005 Rev3. He told them what bike and rider weight and is quite happy with the result. The website is here. http://cannonracecraft.com/catalog/default.php

Yes similar You're never sure you're turning it the right way until the jaws move.

Close but not quite American. adjustable wrench

Really imposssible to know over the web how your bike compares. The air cooled bikes are not as crisp as the water cooled bikes but it should run cleanly down at the bottom of the rev range. Things to check on the older bike are rings. After about three years the rings are due for a change. Because they wear so gradually a bike will seem to run fine but is actually quite a bit weaker which becomes obvious once the new ones are in. Check your ignition timing with a timing light. Retarded timing will make the bike run soft off the bottom. Carb jetting is something you can only figure out by trial and error. Sorry but jetting is a time consuming process. No way around it. Also check your exhaust is clear. Gunk can build up in the muffler and suffocate the engine as well as carbon building up in the header pipe. Good luck and let us know what you find.