cilla Posted January 5, 2011 Report Share Posted January 5, 2011 So, I have a Beta Techno '99 that I just picked up off eBay, and its lovely .. apart from one thing .. it doesn't rev out. Its running really rich at the top end, but pulls like a train low down. bags of grunt. I think its been run very oily, probably about 50:1 by the look of it, but that wont affect the mixture, but at least the blue smoke should clear up as the new mix works its way through. The top end almost feels like the choke is on its that bad, not at all crisp. It's got a 150 main jet, is that about right? I notice the jet sizes sold as spares in the Beta dealers go from 120 to 150, so that suggests its on the rich side. Thoughts? I suppose with bags of grunt and a poor top end, I should check the timing too, but it feels very rich to me. Quote Link to comment Share on other sites More sharing options...
nzralphy Posted January 5, 2011 Report Share Posted January 5, 2011 I used to have my techno on a 145 or a 147.5 Start with the needle set to the middle clip position. Check that the choke is seating properly. Put in a new plug. Clean the air filter and oil it properly. Take the front pipe and mid box off and slosh some petrol up and down inside it to clean it up. NOTE let it air dry very well over night!!!!!!! Good luck as they are a nice bike. Quote Link to comment Share on other sites More sharing options...
cilla Posted January 5, 2011 Author Report Share Posted January 5, 2011 Hmm .. well, 150 is close enough to 147.5 to make no difference ... Mid section is off and getting the blow-lamp treatment to burn out as much as possible. Seems to be quite heavy and fouled, rear section has been cleaned up, didnt make any difference, doubt it would really, as its all a straight through pipe in effect. Carbs been off, looks clean as a whistle ... I'll wash the filter next. I suppose it could be a damaged choke seal, it feels too rich to be down to a needle, and anyway, its still rich at fully open, the needle only affects 1/4 to 3/4 throttle, at wide open its all on the main jet. But, I'll check its on middle clip postion. Quote Link to comment Share on other sites More sharing options...
nzralphy Posted January 6, 2011 Report Share Posted January 6, 2011 I found the jet jump down to 147.5 to be huge. Try it. Quote Link to comment Share on other sites More sharing options...
cilla Posted January 6, 2011 Author Report Share Posted January 6, 2011 I found the jet jump down to 147.5 to be huge. Try it. Hmm, I think I have a 135 and a 140 somewhere ... Quote Link to comment Share on other sites More sharing options...
cilla Posted January 9, 2011 Author Report Share Posted January 9, 2011 Hmm, I think I have a 135 and a 140 somewhere ... Well, the plug was black and practically dripping, so I've stuck the 135 in .. can't say it's exactly crisp, but it is better and doesn't leave a trail of blue smoke everywhere now Anyway, I reckon it's close enough ... my first trials machine, so lots to learn. Spent the afternoon balancing and popping wheelies ... amazing what difference following the hints on a few videos makes!! So enough spannering and time to get some riding in ... Cheers. Quote Link to comment Share on other sites More sharing options...
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