Let's see, this happened on your last trip, or since ? 70k ? 50 something MPH ? oh well, how about fuel restriction ? You say it runs fine through fourth gear.. By that time you would have consumed a bit of fuel and full flow would be needed. Two causes; air lock at the cap, fuel line obstruction. Under the heading of obstruction we can add faulty petcock, poor vacuum supply to same. Disconnect the fuel line from the carbs and the vacuum hose. use a small syringe to open the diaphragm in the petcock (insert syringe and pull plunger back) allow fuel to flow into a container. Let at least 1/'2 gallon flow to see if an air lock shows. If the flow slows, open the cap and see if it resumes. That's a full check of the whole fuel delivery system. Check your tank for rust. Get enough and it plugs up things. # it takes almost a half mile to run the carb bowls dry without any supply and if there is a restriction of some kind and the flow is reduced, that distance would increase. Hence, it would run fine for quite some time. Eventually the demand would outstrip the supply.. like maybe at a sustained higher speed ? The "ticking" and the muffled exhaust indicates to me a lean condition.. like running out of fuel. I'm sure you have ruled out any other system failures; ignition, clutch, etc. So much for on-line guessing.
--- On Mon, 7/13/09, steveday <[email protected]> wrote: From: steveday <[email protected]> Subject: [Nighthawk Lovers] poor, poor acceleration To: "Nighthawk Motorcycle Lovers!" <[email protected]> Date: Monday, July 13, 2009, 10:42 PM Hi everyone, Just since my ride from Montreal to Toronto a week and a half ago, I've had some troubles with acceleration on my 1984 550. It only happens at speeds above 70 kph, that is, in 5th and 6th. Doesn't seem to be connected to rpms as the bike has full punch through 1st, 2nd, 3rd, 4th... I'll be riding along and when I get out of town and the speed limit rises, my twisting the throttle won't do anything... I can open the throttle all the way, hold it there, and the bike'll sit there, then sputter slowly and in little bursts, it'll accelerate. At 90k today there was no response and it dropped to 70k... i let off and tried again and got some response, got back to speed. I swear that when I lean down to listen, I hear something happen when I open the throttle, even if the engine isn't responding. In 6th, there's sometimes a bit of a tick that comes on when I open the throttle and receive no response, and the spurts of accel I do get sound a little muffled... ANYWAY. So I ran some seafoam thru the tank, nothing happened and so I flooded the carbs with seafoam, let sit and started, took it round town and nothing improved again. I just changed my plugs (don't think that's it, but we'll see tomorrow morning). I think it's somewhere in the fuel line. I also have a couple of loose spots where air may be getting in just where the air feed connects to the carbs... that could have something to do with it, but the bike's always had those holes, so... meh? I'm hoping to leave in a day or two on a trip south to kentucky then head over to boston to visit my girlfriend, but i don't think i'll be leaving if I don't resolve this! Advice, please?! ps: suggestions of places to go in the states-- kentucky, wva, tennessee, ohio areas? --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "Nighthawk Motorcycle Lovers!" group. To post to this group, send email to [email protected] To unsubscribe from this group, send email to [email protected] For more options, visit this group at http://groups.google.com/group/nighthawk_lovers?hl=en -~----------~----~----~----~------~----~------~--~---
