newnewmember Posted August 3, 2019 Report Share Posted August 3, 2019 (edited) Hi, I am having some issues setting up this air cooled mono, its recently had a full engine rebuild, I have cleaned out all the exhaust system and repacked it, i have had barrel off for inspection and this would appear to be correct, i have stripped the carb down and to be honest its very clean(original 26mm TK), it would run then suddenly stop...this faulted to the ht secondary ...replaced aok, i rode it 3/4 throttle up a long hill and then did a plug chop)nicebrown/tan colour(, the problem is lower down in carburation especially when warmed up, i believe the pilot maybe a tad weak, anyhow iset air screw to 2 out, and rode it around fine tuning on air and tickover then it started to hunt at tickover and take a little while to settle down after revving, its also had reeds checked and they are spot on no daylight on either set/no damage, from 1/4 throttle it feels fresh and will pick front up no problem 1/2/3 gear.......it maybe how these bikes are i dont know ive never had one before.I havent checked timing, its got a new ht coil new ngk plug capnew ngk5 plug, its not drawing air in everything tight, air filter been cleaned and re-oiled(lightly)........? Im thinking a dodgy crank seal cant be after rebuild 30 hours ago(i.e. before i had it) Edited August 3, 2019 by newnewmember Quote Link to comment Share on other sites More sharing options...
b40rt Posted August 3, 2019 Report Share Posted August 3, 2019 Certainly sounds like an air leak, have you sprayed it while running ? If its the ignition side crank seal, there will more than likely be some 2 stroke residue in the casing. Quote Link to comment Share on other sites More sharing options...
newnewmember Posted August 3, 2019 Author Report Share Posted August 3, 2019 (edited) history, when i went to see bike..it started second kick....but seemed rich off the bottom but sounded OK, got it home and air screw was 1/2 turn out from full in, so i looked up what it should be and backed it out to 2 turns improved things greatly....then it would randomly cut out(traced to faulty ht coil this was replaced and resolved this issue), cleaned and repacked exhaust and checked carb(spotless inside) running a 42 pilot middle clip and 140 main, had a look again today got it warmed up, then it started again when warm, at 2 turns(iy took about 6 kicks to sart from cold/no check/warm day) so wound the slow screw out to 4 and speeds up and when revved takes longer to get back down, so slowly turned it back in and surprise suprise ended back to 1/2 a turn out, now it feels slightly rich off bottom but its very slight and the surging dissapears, so i tried an extra 1/4 out and the surging starts to re-appear......this points to a richer slow jet needed.next step 45?? or a custom file out of 42?? hmm or could it just be the the richening of the pilot cct is masking a very slight main/engine air leak? I will do a leak test next before changing slow/pilot jet.......! Edited August 3, 2019 by newnewmember 1 Quote Link to comment Share on other sites More sharing options...
slack Posted August 5, 2019 Report Share Posted August 5, 2019 Hello mate, I have had the problem of bike running rich off the pilot for some years now... I didn't realize how bad it was until I tried a different carb off my mates bike runs perfect all the way through rev range. I have tried pilots from size 36-42 with no joy. I have tried the Kihien flat slide but a pain to set up so put Tk back on.. If you want to send me a pm with your number I will gladly pass on some of what I have tried.? Quote Link to comment Share on other sites More sharing options...
newnewmember Posted August 5, 2019 Author Report Share Posted August 5, 2019 1 hour ago, slack said: Hello mate, I have had the problem of bike running rich off the pilot for some years now... I didn't realize how bad it was until I tried a different carb off my mates bike runs perfect all the way through rev range. I have tried pilots from size 36-42 with no joy. I have tried the Kihien flat slide but a pain to set up so put Tk back on.. If you want to send me a pm with your number I will gladly pass on some of what I have tried.? Hi, im asuming you put a new 26mm TK carb on ? Quote Link to comment Share on other sites More sharing options...
newnewmember Posted August 5, 2019 Author Report Share Posted August 5, 2019 Im still waiting for a part to complete the leak test, before i look at it further. Quote Link to comment Share on other sites More sharing options...
newnewmember Posted August 5, 2019 Author Report Share Posted August 5, 2019 On 8/3/2019 at 3:03 PM, b40rt said: Certainly sounds like an air leak, have you sprayed it while running ? If its the ignition side crank seal, there will more than likely be some 2 stroke residue in the casing. Took flywheel of and plate yesterday, seal looks mint no signs of leakage or residue, also took clutch side off that seal LOOKS fine but I will still leak test to tick that area off Quote Link to comment Share on other sites More sharing options...
lineaway Posted August 6, 2019 Report Share Posted August 6, 2019 250`s ran good, 350`s not as well. When the rebuild was done, was the mid pipe repacked or at least burned out? I assume new main bearings with the rebuild. Quote Link to comment Share on other sites More sharing options...
slack Posted August 6, 2019 Report Share Posted August 6, 2019 22 hours ago, newnewmember said: Hi, im asuming you put a new 26mm TK carb on ? No... the carb I tried was off a used pinky couldn't believe the difference in performance. What we have realised after getting the barrel rebored with Wossner piston the port timing was wrong. I have had to put two base gaskets on to compensate for this?? Also two of my mates have had to do the same.. I 1 Quote Link to comment Share on other sites More sharing options...
newnewmember Posted August 6, 2019 Author Report Share Posted August 6, 2019 18 hours ago, lineaway said: 250`s ran good, 350`s not as well. When the rebuild was done, was the mid pipe repacked or at least burned out? I assume new main bearings with the rebuild. I have just done the the exhaust and repacked it, all mains conrod piston kit wossner seals gaskets etc done 30 hours ago, the pistoni is 8180DA I think this may make 263(dont know), the bottom end although a tad rich does pick the front up no probs in 1st four gears, its just the tickover issue when warm Quote Link to comment Share on other sites More sharing options...
newnewmember Posted August 6, 2019 Author Report Share Posted August 6, 2019 1 hour ago, slack said: No... the carb I tried was off a used pinky couldn't believe the difference in performance. What we have realised after getting the barrel rebored with Wossner piston the port timing was wrong. I have had to put two base gaskets on to compensate for this?? Also two of my mates have had to do the same.. I Hi, which piston part number? Quote Link to comment Share on other sites More sharing options...
newnewmember Posted August 7, 2019 Author Report Share Posted August 7, 2019 Update, leak test.... issue found around reed housing, cleaned and re sealed now ok, I now am able to back pilot out another 1/2 turn and this is the best setting for how the bike is with the TK carb, I let it cool down 2 hours later, then try to start it 8 kicks later starts runs fine, not happy with this, so I have now fit the OKO 26mm with similiar jetting to TK, its running but TOO rich, however it is starting 1 st kick now...just need some time to dial it in ? Quote Link to comment Share on other sites More sharing options...
slack Posted August 7, 2019 Report Share Posted August 7, 2019 Pass? If you put the wossnor pistons and standard piston together (using the gugeon pin) the wossnor piston has a taller crown.. Quote Link to comment Share on other sites More sharing options...
slack Posted August 7, 2019 Report Share Posted August 7, 2019 3 minutes ago, newnewmember said: Update, leak test.... issue found around reed housing, cleaned and re sealed now ok, I now am able to back pilot out another 1/2 turn and this is the best setting for how the bike is with the TK carb, I let it cool down 2 hours later, then try to start it 8 kicks later starts runs fine, not happy with this, so I have now fit the OKO 26mm with similiar jetting to TK, its running but TOO rich, however it is starting 1 st kick now...just need some time to dial it in ? I will be at Buttsfield this Sunday as the northern classics has been cancelled if you want to have a bit crack. Quote Link to comment Share on other sites More sharing options...
newnewmember Posted August 7, 2019 Author Report Share Posted August 7, 2019 5 minutes ago, slack said: I will be at Buttsfield this Sunday as the northern classics has been cancelled if you want to have a bit crack. So the wossners alter the Squish,/compression, i only know what ive seen on this bike, cheers Quote Link to comment Share on other sites More sharing options...
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