herman Posted October 8, 2015 Report Share Posted October 8, 2015 My model 199 a with the standard Bing 28mm is having an overflow issue. Just about every bike I have bought has had this problem and each one was remedied with a new float needle jet...... except this one. I have adjusted the float until I'm blue in the face. I either have no flow or over flow. I must admit my average mechanical skills have eroded over time, but my next guess is a bad float. Anybody want to weigh in and help an old feller that just wants his Bul to quit leaking so he can enjoy it? Quote Link to comment Share on other sites More sharing options...
mike350 Posted October 8, 2015 Report Share Posted October 8, 2015 Hi, From an originality standpoint I understand that you want to stick with the Bing. I tried many new parts doing the same thing. However, from one old feller to another and assuming that you want to ride the bike, I'd say give up on the Bing and go Mikuni. It starts and runs better and is so easy to set up. You will need a new rubber collar too. I also have a 199 and an RL250! Good luck. 1 Quote Link to comment Share on other sites More sharing options...
herman Posted October 8, 2015 Author Report Share Posted October 8, 2015 Thanks, Mike. I actually found an earlier thread detailing the Mikuni jetting and am thinking that's the way to go. I picked this bike up to use as both a rider and a loaner to some guys I know that are thinking about taking up trials. Plus I just like the Bultaco marque...... As far as originality goes I can always save the Bing and keep it with the original and unbelievably awful air filter / boot setup. I went with the one piece filter boot, which looks like a much better alternative. 1 Quote Link to comment Share on other sites More sharing options...
pschrauber Posted October 8, 2015 Report Share Posted October 8, 2015 Well I had likewise Bing issues too which were very similar. I too changed the valve float as the rubber of the old one looked porous and then had an issue with the carb overflooding not always but frequently when the bike did not stand or roll horizontal. It turned out that the new valve float I purchased from Bing (took some weeks to order that tiny little piece) was different in overall length. The new one I got was 1mm shorter, (14mm instead of 15mm). I did not check the float valve when I replaced it and 'cause I thought they should be machined in the exact like way which wasn't the case ... You can try to compensate the different length by bending the little metal strip of the float for adjusting. I did this, however it did not work as well as I thought, may be because of the more angled metal strip no clue here . In the end I have now left the old float valve and the bike runs fine again. So you might check the length of the float valve too. Quote Link to comment Share on other sites More sharing options...
feetupfun Posted October 9, 2015 Report Share Posted October 9, 2015 The OKO carby also goes well on the 325 Bultaco Sherpa T 2 Quote Link to comment Share on other sites More sharing options...
lbhbul Posted October 9, 2015 Report Share Posted October 9, 2015 Herman, the Bing can be a hand full & expensive. For a 26mm mikuni , 100 main 40 pilot seems to be a good starting place.(alum. carb) We have an OKO 26mm on one 199, sorry don't know the jetting but it was used for Nationals this season. As Mike says above, you need the intake rubber that accepts both new carbs. Good luck Larry Quote Link to comment Share on other sites More sharing options...
herman Posted October 9, 2015 Author Report Share Posted October 9, 2015 Just got of the phone with a friend that said he was using the OKO on his Fantic with great success. He said Mid Atlantic Trials can set one up w/ proper jetting for about 130 bucks. I have a buddy that told me he might have a couple of 28 Mikunis lying around. If so, and I can snag one, I'll use the jetting you suggested to get started. He echoed what you said about the Bing saying that he had trouble with them when new..... and 40 years later it hasn't improved! Thanks! 1 Quote Link to comment Share on other sites More sharing options...
herman Posted October 19, 2015 Author Report Share Posted October 19, 2015 Installed an OKO carb per a friends advice and she starts and runs great! 1 Quote Link to comment Share on other sites More sharing options...
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