pattonfamily Posted June 7, 2006 Report Share Posted June 7, 2006 My daughters 2004 Beta 125 is trying to do the Michael Jackson "moon walk". The bike starts fine, runs about 20 minutes, when it warms up good it suddenly bogs down as if you completely covered the air intake. She says sometimes it just quits, sometimes it runs backwards. When we attemp to restart it, it wants to run backwards. After about cool down period it will restart and run fine for another 20 minutes and then repeat the process. We have tried advancing and retarding the stator, and we have replaced the "black box". Has any body seen this before? Any suggestions on a solution? Please help...trials is hard enough going forward! Quote Link to comment Share on other sites More sharing options...
andy_290 Posted June 7, 2006 Report Share Posted June 7, 2006 My Sherco did this about 3 months back, I had to replace the stator to fix it. Quote Link to comment Share on other sites More sharing options...
ahamayfrank Posted June 8, 2006 Report Share Posted June 8, 2006 Charlie, I am surprised that no one has jumped in here to offer advise, that is familiar with Beta motorcycles. In my response I am making assumptions because I have no experience with modern Betas. In general, most ignition systems work in a similar manner between brands. In the past motoplat ignitions (if that is what you have) have had a reputation for heat related failure, but that may have improved. Skipping all details and assuming all wiring and connections are ok the two most likely problems are the black box (ECM, CDI or whatever others call it) and the stator. These two components work together controlling ignition timing. If Sara Quote Link to comment Share on other sites More sharing options...
movingtarget Posted June 8, 2006 Report Share Posted June 8, 2006 I just registered today to ask about the exact same problem. My 2004 beta 270 is not starting properly, and when it does it sounds terrible, lots of backfiring when trying to start it up. When I finally do get it going it rolls backwards. Havnt the foggiest idea what to do with it and what you said about the black boxs and coils etc... went right over my head Quote Link to comment Share on other sites More sharing options...
ahamayfrank Posted June 9, 2006 Report Share Posted June 9, 2006 MT, Once again I wish someone with recent Beta experience would step up, but not so far. I tried to make it simple but evidently failed. Short and sweet the most likely problems are either stator (under the flywheel usually on the opposite side of the kickstarter, but this is a Beta (ha, ha I couldn Quote Link to comment Share on other sites More sharing options...
pattonfamily Posted June 9, 2006 Author Report Share Posted June 9, 2006 All, Thanks for the comments and suggestions. I'll replace the stator and let you know my results. MT - If your problem seams heat related, start with the stator which suffers the most fluctuation in temperature since it's inside the engine covers. That's the only thing I haven't already replaced. The stator is found under the right side cover behind the fly wheel. You'll need to use a puller to remove the flywheel, but its pretty simple. Besure and use the key to reinstall and align the fly wheel on re-assembly because this alignment is critical to timing the ignition. If your problem is not heat related, it's possibly the black box, which is found inside the frame between the gas tank cap and the steering head. From everything I've heard, its either the black box, or the stator. The only other possibility I've heard about is that the key that aligns the fly wheel on the crank may be sheared causing mis-alignment. That is not the case on mine, but you should look for that when you pull your fly wheel off. Thanks again everyone!!!! Quote Link to comment Share on other sites More sharing options...
ron Posted June 9, 2006 Report Share Posted June 9, 2006 FYI ALL I have already spoken to charlie.. and sent him all parts necessary.. and a note with some ideas.. So he has all the info he needs.. the Issue is and will be resolved ..I'm sure charlie will be happy to tell you his findings.. Quote Link to comment Share on other sites More sharing options...
movingtarget Posted June 9, 2006 Report Share Posted June 9, 2006 thanks for all the help people, will have a look later on tonite. Starting to have doubts about beta, its my first trials bike and I've had nonstop trouble with it since I got it, dont think its ever lasted more than a full days riding without something going wrong with it. Quote Link to comment Share on other sites More sharing options...
pattonfamily Posted June 9, 2006 Author Report Share Posted June 9, 2006 MT - Don't give up on your Beta. I have three Beta's, including a 1998 Techno which I have been competing on for years. I have been EXTREMELY PLEASED with every one of them. They have been bullet proof bikes and the support from BETA USA has been OUTSTANDING. When you buy a used bike, you not only buy a brand, but you also buy the treatment it has received including the maintenance (or lack there of). So you might have some maintenance/care issues to straighten out. This is true with any used bike. If you need advice, call Ron at BETA USA, and I am confident you will get great technical advice and assistance, as well as quality service. BETA is truely FIRST CLASS. I'll always have one in my inventory. Quote Link to comment Share on other sites More sharing options...
movingtarget Posted June 9, 2006 Report Share Posted June 9, 2006 Dont worry I havnt givin up yet, just got back from work and once I've eaten will check the flywheel first. If that looks ok then I would certainly like to seek further advice. Seeing as I live in scotland would there be somebody closer to home I could try contacting for advice? When the bike was running, it did seem to be 'skipping beats' even when warmed up, could this be too much petrol or another side effect of the timing being off? Thanks Quote Link to comment Share on other sites More sharing options...
movingtarget Posted June 11, 2006 Report Share Posted June 11, 2006 On the NW coast Quote Link to comment Share on other sites More sharing options...
movingtarget Posted June 12, 2006 Report Share Posted June 12, 2006 Took the flywheel off and the key was snapped in half, flywheel was about 90degrees out. Least now I know what the problem was, although I'm wondering why it happened. I was able to loosen the nut that holds the flywheel on just by using a spanner and holding the wheel with my hand. Does this mean that it was not tightened enough which allowed it to break the key? Much thanks to Gary(if you read this) for sending me a new key. Quote Link to comment Share on other sites More sharing options...
totalshell Posted June 13, 2006 Report Share Posted June 13, 2006 this is a classic example of fear the worst, spend ages agonising over the problem, then sharing it. Only to find the real problem was a really simple one to solve,( one of the real benifits of a site like TC) mechanical things in 2006 rarely go wrong and when they do its inevitably the small things and usually the more common things, happily in this case it was also one of the cheapest things to replace i think a good indicator of how reliable something is would be the size of the parts dept. at the distributor. having lived and worked in silsden for umpty years i've seen lampkins go down the post office to post boxes and bags and bits off to no doubt repair bikes and i've never seen more than an armfull of packages left on the post office counter and if you consider all the Betas out in the uk that has to say their pretty reliable.. Quote Link to comment Share on other sites More sharing options...
pattonfamily Posted June 13, 2006 Author Report Share Posted June 13, 2006 Thanks everyone! Ron - I received your care package last Friday with everything needed including the fly wheel puller and complete instructions. I have replaced the stator and the first test drive was successful. My daughter will ride the bike on Thursday and well see how it does for her, but I think we've resolved the problem. Quote Link to comment Share on other sites More sharing options...
tonyp884 Posted June 13, 2006 Report Share Posted June 13, 2006 Target, I do not have a Beta. But, I've had 28 motorcycles over the years. Montesa, Carabella, Honda, Yamaha, Fantic, Gas Gas,.....etc. Now, having said that, I've had several occassions where the key was sheared. It is designed to fail first in the event of a problem. That way, you should not have damage to the crankshaft, or the flywheel. Be sure to clean the crankshaft shaft, in the area where the flyheel mates up, and the inside of the flywheel real good. You may have, scratch that, will likely have some metal transfer on the mating surfaces. This must be cleaned up really well so that you can obtain a good tight fit to prevent another key from shearing. I have always used some valve lapping compound on the shaft, then put the flywheel on the shaft, and "lapped" the pieces untill the surfaces had a good clean mating surface. I hope that made sense! Tony Powers Charlotte, NC USofA Quote Link to comment Share on other sites More sharing options...
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