Thank you for your help thus far. The bike is still belching blue smoke when it gets warm. It gets worse as it warms up. It is basically clear at first, but then it goes to smoke again. I will describe what I have already done below:
-Cleaned carbs -replaced piston rings -replaced engine gaskets -replaced all seals above the gear box -set the valve timing, -replaced valve seals -cleaned carbon from piston and bottom of valve area What am I missing? Why is there still blue smoke? please help. On Friday, April 3, 2015 at 9:31:31 PM UTC-6, Allen wrote: > > What do you mean by " when the pins are starving the carb" ? Also ar you > letting the bike get hot? You pretty much need to let it warm up and ride > it for 10 minutes to get a good plug reading. Otherwise they will be black > from having the choke on. So are your plugs black with dry soot, oily, or > wet with gas? Does the bike run better with the airbox door removed? Does > it run better with some choke on? > You can buy a leak down tester from harbor freight for a reasonable price. > Certainly it is cheaper than doing an unnecessary rebuild. > We had a 82 nighthawk 650 that needed to run without the airbox door > despite having the correct jets. Symptoms of that bike was misfiring at > 5000+ rpm and was worse in higher gear or larger throttle openings. > > Allen Thomas > On Apr 3, 2015 12:48 PM, "ember630" <[email protected] <javascript:>> > wrote: > >> Hi Allen, thanks for your response. I set the carbs according to the >> owners manual. It is of course possible that it's too rich, but it even >> does this when the pins are starving the carb. Just replaced the plugs. >> I'm a little concerned because the spark plugs have created more burnt >> carbon residue than I would expect considering I've only turned it over in >> the garage and ridden up the street 500m to the gas station. But yes, >> they're brand new and the gap is right (0.8mm, owners manual says 0.8-0.9 >> for the gap). I do not have access to a leak down detector. Any other >> thoughts? thanks for your help. >> >> On Thursday, April 2, 2015 at 3:26:00 PM UTC-6, Allen wrote: >>> >>> Blue smoke is an indicator of a very rich mixture. Do you smell oil >>> burning? What do your plugs look like? Do you have access to a leak down >>> tester? I would spend some time diagnosing before committing to tearing the >>> bike apart. >>> >>> On Thu, Apr 2, 2015 at 4:15 PM, Javier Garcia <[email protected]> wrote: >>> >>>> Isn't possible that your carbs were set too rich? >>>> >>>> On Thu, Apr 2, 2015 at 4:06 PM, ember630 <[email protected]> wrote: >>>> >>>>> Hi, >>>>> I've been reading a lot on this forum and it seems this is the place >>>>> to be. I just cleaned the carbs on my 1984 CB450SC and got it going for >>>>> the season to find out when I put it in gear, it burns bluish smoke from >>>>> the exhaust and loose power when the throttle is aggressively turned. I >>>>> know it's not the carbs, so I'm pulling the cylinder heads off tomorrow >>>>> and >>>>> checking the pistons, chambers, and rings conditions. I suspect I will >>>>> find oil leaking into the piston area there. As I understand, it's >>>>> probably not worth fixing if the chamber is damaged or misshaped, so I'm >>>>> hoping it's just the piston or piston rings. DOES ANYONE KNOW WHERE I >>>>> CAN >>>>> BUY A NEW SET OF PISTON RINGS OR NEW PISTONS FOR A CB450SC? >>>>> Thank you for your help. And if you have any other ideas about what >>>>> could be causing the problems with my bike, I'd be very grateful for a >>>>> response. >>>>> thanks >>>>> >>>>> -- >>>>> You received this message because you are subscribed to the Google >>>>> Groups "Nighthawk Motorcycle Lovers!" group. >>>>> To unsubscribe from this group and stop receiving emails from it, send >>>>> an email to [email protected]. >>>>> To post to this group, send email to [email protected]. >>>>> Visit this group at http://groups.google.com/group/nighthawk_lovers. >>>>> For more options, visit https://groups.google.com/d/optout. >>>>> >>>> >>>> -- >>>> You received this message because you are subscribed to the Google >>>> Groups "Nighthawk Motorcycle Lovers!" group. >>>> To unsubscribe from this group and stop receiving emails from it, send >>>> an email to [email protected]. >>>> To post to this group, send email to [email protected]. >>>> Visit this group at http://groups.google.com/group/nighthawk_lovers. >>>> For more options, visit https://groups.google.com/d/optout. >>>> >>> >>> -- >> You received this message because you are subscribed to the Google Groups >> "Nighthawk Motorcycle Lovers!" group. >> To unsubscribe from this group and stop receiving emails from it, send an >> email to [email protected] <javascript:>. >> To post to this group, send email to [email protected] >> <javascript:>. >> Visit this group at http://groups.google.com/group/nighthawk_lovers. >> For more options, visit https://groups.google.com/d/optout. >> > -- You received this message because you are subscribed to the Google Groups "Nighthawk Motorcycle Lovers!" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/nighthawk_lovers. For more options, visit https://groups.google.com/d/optout.
