john.b Posted May 27, 2009 Report Share Posted May 27, 2009 Sound a bit like carb problems. I noticed Copemech was thinking the same as well. Looking at your original post you mentioned that everything was fine until you changed your air filter. Could some filter fibres or dirt have been sucked in to the pilot circuit of the carb. Have you taken out the pilot jet and blown compressed air through the jets and drillings of the carb. Also is the choke on the carb seating properly when off. Quote Link to comment Share on other sites More sharing options...
clav3 Posted May 27, 2009 Report Share Posted May 27, 2009 Hi all, Burnt out my muff last week and over did it. The packing turned molten and started to rattle when cool. I decided to cut a small hole in each section just to have a look. Eventually got all the packing out of the front ( it looked like medium steel wool) and decided to do the back which didn't have much left in it (fiberglass). I cleaned and wash it and thought I may as well try repacking. I used medium grade steel wool in front an rear sections and just packed it as tight as I could. A mate of mine who is very good with a welder, welded the pieces back on. By the way the front hole was just forward of center and underneath about 20mm X 25mm. The rear hole was about 50mm X 50mm and cut to pretty much to line up with the plastic guard that screws on to the muff. The bike now sounds great. Much like it did when it was new. I took it out to test the next day. Unusually cold and wet conditions. Still cant get it to run with a 42 at 1 1/4 turns but runs well with a 45 at 1 1/2 maybe a little rich but many wouldn't think so. I did try the Dellorto with standard settings 33 pilot 2 3/4 turns out D36 on 3rd groove and it seemed to run great, very minimal pinging if any (this may be due to the cold wet weather) and pilot gas screw in a full turn. I have to state very strongly that with the Dellorto fitted you would never no there was any problem. It just runs so smooth down low it's a pleasure to listen to. But....the linear power of the Keihin makes the bike far easier to ride, particularly in slow slippery conditions, and with faster power when needed. The Dellorto gas screw can be adjusted lean enough to give a very smooth throttle and still idle well. The Keihin now needs a richer bottom, slightly blubbery,for it to idle, but still no where near as smooth as the Dellorto. Repacking the muff made the bike sound like new but I feel minimal change to performance and running. I'd be surprised if there is an air leak especially after your findings Neo and the fact that it runs well with the Dellorto. ( For those not wanting to bog down in this 6 page thread, I have allready tried a brand new Keihin with the exact same results) I will be freshening up the top end in the next few weeks and we'll see after that. Cheers. Quote Link to comment Share on other sites More sharing options...
neo Posted May 27, 2009 Author Report Share Posted May 27, 2009 Burnt out my muff last week and over did it. The packing turned molten and started to rattle when cool. .......By the way the front hole was just forward of center and underneath about 20mm X 25mm. The rear hole was about 50mm X 50mm and cut to pretty much to line up with the plastic guard that screws on to the muff....... I will be freshening up the top end in the next few weeks and we'll see after that..... Hi Clav,WoW! Sounds like you've been having some fun with fire Any chance of posting up some photo's of the holes you cut out?....or could you emiail them to me and I'll posted them up. I'm curious....if you do a conpresson test and your compression comes out as good as mine did, why would you bother with a "freshen up"? Best of balance. Neo Quote Link to comment Share on other sites More sharing options...
neo Posted May 27, 2009 Author Report Share Posted May 27, 2009 I use Hunters' Carbo Clean Hi Stork, Where do you buy this stuff? Best of balance. Neo Quote Link to comment Share on other sites More sharing options...
stork955 Posted May 28, 2009 Report Share Posted May 28, 2009 Gday Neo, Hunters products make it, they are nearby me in Tassie. Try this link, http://www.apchem.com.au/HTML/Industrial/A...ngine.html#8770 which I just found via a quick google. They have a similar product at the bottom of the page. Cheers, Stork Quote Link to comment Share on other sites More sharing options...
copemech Posted June 2, 2009 Report Share Posted June 2, 2009 Wonder if Neo found any more odd stuff in his carby? Quote Link to comment Share on other sites More sharing options...
neo Posted June 2, 2009 Author Report Share Posted June 2, 2009 Cope, Sorry I got some bad news from work a few days ago....so I haven't really been in the mood for working on bikes since. There are lots of changes (which will be taking up my time) on way.....but as the T101 would say....."I'll be back"!!! Best of balance. Neo Quote Link to comment Share on other sites More sharing options...
copemech Posted June 3, 2009 Report Share Posted June 3, 2009 Gee, do i understand! Get on with it! Best to you Quote Link to comment Share on other sites More sharing options...
neo Posted August 15, 2009 Author Report Share Posted August 15, 2009 Hi Gents....here's an old thread....back from the dead Just discovered something interesting these past couple of week. On the odd occasion my bike starts hunting (just mildly now days and only when after an hour or so's riding) if I turn the air-mix screw all the way in (fully rich) then rev her up high to clear her out. When I turn the screw back again the bike runs OK.....not perfect but OK. I've done this three time recently and it's worked every time. What do yo think gents? ....not a cure, but a workaround I think. Clav, maybe you could try this on your keihin too?? Best of balance. Neo Quote Link to comment Share on other sites More sharing options...
peterb Posted August 16, 2009 Report Share Posted August 16, 2009 Hi Neo, I started reading this thread today and got to page 3 and decided to see what the eventual fix was, hopefully on page 6 - there isn't one! Are you still having problems? Somewhere early on in the thread there are a few photos of your Keihin, these show the vent pipes going up and then down. I've never known a bike to run well with this set up as there cannot be any self drain facility from either vent due to an approx 25-30mm of extra height the fuel must travel before it can drain. The top of the float bowl must be vented to atmospheric pressure to allow the carb to work properly. Just to check this and to rule out this possibility, have you tried removing the vent hoses? Also, the float bowl drain should only run downwards. If this is ok then have a look at replacing the mag side crank oil seal, not an expensive job to do and worth trying out to rule out this likely possibility. I guess by now you have fitted an inline fuel filter. I've ran Keihins on Gas Gas since 2001, only problems have been with not fitting an inline filter and making sure there are no splits in the inlet hose. Have always ran faultless otherwise. Best needle for me on 300 PRO's and 321 GG has been a GJH, the recommended JJH runs a little quick at the low end. Bye, PeterB. Quote Link to comment Share on other sites More sharing options...
neo Posted August 16, 2009 Author Report Share Posted August 16, 2009 Thanks for your suggestions Peter.....but most of this has been covered, double-checked, tried and tested in pages 3 to 6 ;-) Interestingly I have had a lot of success with the 3 tubes I use on my Keihin .....And I would recommend this (the way I did it) to anyone. Best of balance. Neo Quote Link to comment Share on other sites More sharing options...
peterb Posted August 16, 2009 Report Share Posted August 16, 2009 Hi Neo, Maybe I should have a read a little further! I guess you still have the same problem then, if it were me, then I'd strip the motor and check for the possibility of a leaking crank case gasket, or maybe a pinhole in the crankcase (had one on a Fantic 301 once) I couldn't stand riding a bike that didn't run properly. Hopefully something would show up. Good luck with this one, PeterB. Quote Link to comment Share on other sites More sharing options...
neo Posted August 16, 2009 Author Report Share Posted August 16, 2009 Hey Stork,...Thanks for your additional input....I knew I'd forgotten someone in my list of Knights in shining armour Right Gents, I know Jon has mentioned this Leakdown (pump-up) test in other threads. And since then I've been itching to give it a go. But the soapy spray idea has convinced me really it's worth doing. So last night I set about making a "pumping point" out of a drilled out spark plug and an inner tube vale stem. So with any luck tomorrow, being a rainy day, I'll finish it, plug up the holes and pump her up......Question is how many PSI?....or is it the more the merrier And how slowly should this pressure drop? Best of balance. Neo Hi All,This is what I discovered ......nothing!!....no leaks found at all Ok I've pictured my "Leak Down Kit" so I explain how I used it. Fitted the "pump up" vale (as pictured) in the spark plug hole. The yellow cap fits perfectly (with a bit exhaust paste) into the exhaust port (comes from a plastic petrol container which is very common in Aus). Then bolted the header pipe back on to hold the cap firm. I made an inlet plug out of some PVC waste pipe. Heated one end, put a bit of silicone in it the clamped it in the vice. It fitted snugly into the rubber inlet manifold. I also inserted a thin tie cord into a reed vale to make sure the valve stayed open. I then removed the flywheel and stator (great suggestion Stork!) and the bash plate.....then I got ready with the soap spay. Lastly I put that yellow pipe on the oil breather, then into the little plastic container filled with soapy water....My theory here was that if the right hand seal was leaking the air would make it's way out via the oil breather and been seen in bubbles. So...first problem.....I have no bicycle pump ...what the hell, use the electric tyre pump . So a quick burst with that...oops she's hit 10psi already..."what the hell"... start spaying all over....Nothing Hmmm.... "What concerns me about all this process is the bike normally starts hunting when it's hot. But this engine is cold" Ok lets tun up the pressure oops she's hit 20psi now...what the hell... start spaying all over again....Nothing Ok lets tun up the pressure oops she'd hit 35psi now ...what the hell... start spaying all over again....Nothing She held that 35 PSI...and dropped to 32 PSI some 20 mins later....And I reckon the only reason it dropped at all was because I kept taking pressure readings On the plus side....this is one hell of sealed engine I have .....On the negative side....I still don't know what's wrong with this bike Stork what I meant by warm engine is an engine that's not really hot...say less than 15 mins of riding. Even today the engine was hunting very mildly shortly after staring. I rode her for half an hour like that. Then 2 hours later I rode her again and she was as good as gold So all I can say now gents is...."next idea please" Best of balance. Neo Hi Peter, We've kinda covered that too But more ideas are truly welcome I believe the answer will come when when we take into account all the clues ....It's a challenge that I know you guys are upto Best of balance. Neo Quote Link to comment Share on other sites More sharing options...
theshercorider Posted August 16, 2009 Report Share Posted August 16, 2009 Right if this has already been said I am sorry as I only read the first post. Now my bike the other month or so was running rich intermittently, turned out the needle in the carb was not replaced right when i was fiiting something. It sat on top of the slide and sometimes it would not return and run rich etc. Just something to look out for. Quote Link to comment Share on other sites More sharing options...
copemech Posted August 17, 2009 Report Share Posted August 17, 2009 And what fuel ere you running? Neo? Quote Link to comment Share on other sites More sharing options...
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