clarkp

Just a note to let everyone know that if you DO connect the two carb overflows with a loop of tubing (connect them together) you may experience difficulty starting your bike. No more dribbling carb, but it won't start unless you kick the #$!% out of it. The remedy is to cut a 'V' shaped slot (or drill a couple of holes) in the tubing at the top of the loop to vent to atmosphere. Starting problems gone, dribbling carb - gone.

Several youth riders in our club ride the Rev50 and Rev80 with great success. These bikes hold their value well as parents are always looking for entry-level bikes. Beta has done an excellent job of addressing the needs of young riders. Kudos! I know of no problems with these machines. Families in my area love them.

I hear BETA is coming out with a diesel-powered trials bike called the TORK3 - could be just the ticket for you. Is it dribbling gas out the overflow tubes? If so, you could probably use a new needle seat and float needle - could probably stand to connect the two overflows together with one piece of tubing also.

See the second post on this link... http://www.trialscentral.com/forums/index.php?showtopic=2182

Ishy - what you're seeing is the way it was assembled from the factory.

neonsurge - hey, I miss your Ron Jeremy avatar... wha' hoppen? Anyway, in this case, I don't think the Billy T float adjustment will help because I think you may have a problem with the floats shutting off fuel flow. You may want to order a new float needle and seat for your Mikuni to keep it from flooding when you park it with a down hill slant. Also, try the loop of tubing thing where you connect both overflow bibs on the carb w/ a loop of weed-eater fuel line or similar... seems to help with the dribbling and the 'point-it-downhill-burbling' problem - not gone, mind you, just seems a little better. Thinking about retro-fitting my Rev-3 with a nice Amal or Bing... I may have to settle for a Keihin or steal the injection system from one of the new Montesa thumpers...

I like the GasGas-colored fork tubes...

Yes, that could be part of the problem - if the inlet boot is cracked the bike will suck extra air and will be running lean. Some guys say try spraying WD-40 around the inlet boot when its idling and if it revs up, you have a leak. OBTW, as a courtesy, change your personal settings to show everyone where you're located.

Give us a little history... has it been like this all along and running OK, did you just try a new pilot and now it runs different / better / worse...? The obvious would be to suggest using compressed air to clean out all the orifices (orifiae?) BUT - shoot for crisp response right off idle with the 'air screw'. When you whack the throttle open off idle you should have instant response, no bogging and, on the other extreme, you don't want it taking a prolonged time to re-attain idle. If you don't have instant repsonse, keep trying with 1/4 turn adjustments of the air screw until you get the hit you're looking for. Or to paraphrase from the Mikuni manual, (pdf pg. 14-15, document pg. 10-11): Warm up the engine and adjust the throttle stop screw such that the engine is idling about 10-20% higher than the throttle position you're trying to help (usually just off idle for a trials bike). Adjust the air screw left and right by 1/4 to 1/2 turn at a time until you get max rpms. Now re-adjust the throttle stop screw to get back to your normal target idle speed. Now, again, adjust the air screw left and right until you get max rpms. If 1-1/4 turns out and 2 turns out (for example) both give the same rpm, always choose the fewer turns out (1-1/4 is better than 2). In the end, always shoot for what give crisp response right off idle and no prolonged return to idle. If none of this works, trade it in on a fuel injected 4-stroke Montesa... and buy a laptop to tune it with.

Well, I think Yamaha Dude's post clearly shows that the Beta is faster... no question.

Terry - the guys at BETA USA just wanted to get the part from me so they can send it to the parent company for analysis. On the phone they just speculated that there may have been some impurities in the magnesium batch - no one can be sure at this point. They wanted to get me running again as soon as possible and have already shipped my parts. Dabs... good point... I didn't even think about it when I was ordering my other parts - maybe a good 60 oz. shop hammer, some C-clamps, and a couple of cold cervezas would do the job I just don't know which tool to use first... better have another beer to think this over - could take a while...

My advice would be to put it all back together and use a section of pink tubing to connect the two overflow spigots together to stop the dribbling. I would take the Traynor settings as only general guides - not as actual for your bike. It is VERY easy to set the floats (especially if you take that 1/16" and no more rule to heart) such that they don't allow enough fuel to flow and you starve your bike for fuel. Don't make these changes and then go to a trial without testing them - ESPECIALLY if the trials have longish transports between sections, you may set the floats to where you have enough fuel in the bowl to make it to the section and then have the bike die or bog in the section because the trip sucked all the gas from the float bowl and it hasn't had time to refill. So, all that to say, "don't #@%! with it", IMO. Connect the two overflows with a loop of tubing and be done with it. However, if you insist on jacking with the float level... but, like I said, I don't think these setting flow enough fuel - this is my carb - you see how far down mine drops.

I wish I could get this kind of service from my truck dealer... Ron Commo and BETA USA have graciously offered to warranty the sidecase for me - I really never expected that level of service and I couldn't be happier with the team at C & G BETA. All it took was one phone call and they offered to replace the part, no questions, no hassles. Service like that will have me buying another BETA!..(and another, and another...)

lineaway - yes, its an '03 - and that isn't a hose clamp in the background, its the low-pressure spigot on the pump cover... where the hose was attached.

beta boy - yes, my impeller is plastic and is in perfect shape. Given how the casting has eroded I guess I'm glad the impeller is plastic. neonsurge - I still think that Beta is one of the best built machines available and I would buy another one before I bought anything else. The actual pump cover has absolutely NO signs of corrosion at all, just the main side case. To your point, I hadn't really given much thought to it being a QA issue with the casting but I think you may be right; I would expect to see more consistent erosion around the channels if it were impeller cavitation due to low coolant or running plain water. The Silkolene ProCool I use comes pre-mixed and ready to run. So on your thought, it does appear to be a possible quality issue with the casting. I think if you ran plain water, had an air bubble entrained in the system, or ran low coolant to where it couldn't do efficient heat transfer you could have the coolant boil and / or cavitate which could produce this result. I'll give the boys at Beta USA a call tomorrow... Ron, are you lurking?...

You guys just run regular automotive anti-freeze and distilled water at 50:50 mix? I was going to try to repair it with J-B Weld until I took the cover off ... holy crap (literally...) In the picture, that hole at the bottom (lowest point) was constantly pi$$ing a stream about the size of the tip of a pencil - until the cooling system was completely emptied. Glad I noticed it before any heat-related damage was done or I might have had to buy an '05 270.

I DNF'd a trial this morning because of a water leak on my 250. There was a pin hole completely THROUGH the left sidecase - I thought it was a bad casting but upon removal of the water pump cover I saw lots of corrosion to the sidecase in the water pump channels... several holes that are almost through and lots of corrosion to the area around the pump shaft seal. Now I'm pretty sure the coolant has contaminated the gearbox oil too - it looks cloudy. Does anyone have experience with this type of corrosion? I'm running Silkolene ProCool. Do you think a previous owner ran something that boiled or cavitated? It looks like I'm out a sidecase, clutch fibre plates, as well as assorted gaskets and seals.

How's your compression? You must have sufficient spark (at the right time), a good fuel / air mixture, and good compression for a 2-stroke to run. You say the spark and fuel are OK - is it possible that you were running old gas the last time you rode the machine, or that you ran it for a short time and then put it away for a 'couple of weeks'? You may have a stuck ring (lots of goo / carbon around the piston and rings thereby 'sticking' the rings to the ring land or piston reducing your compression. You could pull the head and cylinder and pop in a fresh set of rings (or just clean what you have) OR... (and this is the best I can come up with...) stick it in 4th gear and have a friend help you push start it - pushing generates a hotter spark for a longer period of time than kick starting. If it were me... fresh gas, new plug, and a couple of friends to push... then cold beers all around. If it doesn't start, drink the rest of the beer, if it does start, celebrate by drinking the rest of the beer.

Interesting reply, Charlie... when I installed the SureFlex clutch plates in my old Montesa, several of the fibre 'pucks' had delaminated from the plate - I was never sure why. I do know that the previous owners of both my Montesa and my Beta had used ATF in the transmission.

I have a suspicion that ATF causes the clutch fibre plates to swell thus causing all clutches to drag since there wouldn't be enough 'throw' to adequately separate the plates. Anyone have any experience with this? Is this on track or am I smoking left-handed tobacco? I've switched over to Mobil 1 synthetic and away from Torco MTF 75 - the Mobil 1 seems to help a little with the clutch dragging. I think a wholesale switch to new fibre AND new steel plates along with the Mobil 1 should give me a perfect clutch for the upcoming fall season. What are you running in your bike?

http://www.betamotor.com/media/news/2004_0...rr4t_foto03.jpg Obviously, this engine wouldn't make into a trials bike, but is this a BETA motor, or is this engine sourced from a partner company?

So, what's the actual number of the plug you settled on?

Can you shed some light on this?.. different, how? Does it turn better / worse? Make more / less - smoother / snappier power? etc. OBTW, change your personal settings to show your location...

Back in the glorious 70's we used to call all trials bikes 'plonkers' - probably due only to a knowledge of the Ossa brand. I used to have an Ossa Stiletto flat tracker... I guess I now know why I put my foot down on left turns in the sections!?

Spark plugs lose their starch sometimes, they're cheap... change them out. I never tackle a two-stroke engine issue without starting with a fresh plug and fresh gas. Sounds like you may have had a plug that was on its last legs. We've given you lots of ideas... check your jetting, put in a new plug, and start with fresh gas. You THINK the main jet is a #150... well, is it? And by 'slider' I'm guessing you mean the throttle slide?! The throttle slide cut-away shouldn't be of concern and don't change the jet needle or clip position. You also haven't told us what your pilot jet is - this is one of the most important jets on a Beta. Here is where the jets are: Use a small flat screwdriver to remove the pilot jet and document its number. Also document how many turns out your pilot air screw is - mine is at 1-3/4 turns out. Is your machine is a 250 or a 270 - the 145 main jet and 27.5 pilot jet should put you right on, especially with fresh gas and a fresh plug. We can be of more help when we have your baseline jetting. Also, keep a file on your computer of all your carb settings AND document your changes so you always have a history of where you were and where you are now.