An excellent question. Yes there was some problems with early model 650sc's. Ones that were modified during those years when the bikes were current should have been marked by the dealer as having been done. That's just trivia. I developed some short-cuts to replace the cam chain and related parts but let's not go there yet. Go to one of the parts sites that use illustrations from one of the parts look-up programs like part-smart. You can see what parts are used. If need be, I can describe how it works. In theory, the cam chain and parts should last as long as the rest of the motor. It's not a chain in the classic sense, more like a watch band. Any work on this system can be best cataloged as serious. On a scale of 1~10, it's an 8. You want to repair / replace ? I'll talk you through it.
--- On Sun, 6/14/09, oldschoolgwin <[email protected]> wrote: From: oldschoolgwin <[email protected]> Subject: [Nighthawk Lovers] Re: Cam chain Tensioner reset ? To: "Nighthawk Motorcycle Lovers!" <[email protected]> Date: Sunday, June 14, 2009, 12:33 PM Dennis, On an 83 NH 650 is there anything that can be done to tension the chain if the tensioner is not doing it's job. I hear a chain "slapping" sound upon semi-rapid decelleration on mine. I thought I read something about 83-85 year models may have a spring that has lost tension (replace spring?) or the tensioner arm has stuck for some reason (hmmm - why would this be ?) and that loosening the mounting screw(s) and then retightening allows the tensioner to retension the chain. I have not seen the actual tensioning linkage yet (coming soon I think) so I really have no clue if any of this really applies. It seems it would not have been in the original design intent of Honda. Also how long do we expect the cam chain to last before it has stretched to the point that replacement is required? Is that a horrendous task? Thanks, Paul On Jun 12, 8:40 pm, Dennis Hammerl <[email protected]> wrote: > The article refers to much earlier model 750's. Your's has no such > adjustment. There are no external fasteners or adjusters on a later model. > > --- On Fri, 6/12/09, RicCarr <[email protected]> wrote: > > From: RicCarr <[email protected]> > Subject: [Nighthawk Lovers] Cam chain Tensioner reset ? > To: [email protected] > Date: Friday, June 12, 2009, 12:32 PM > > Hello, > Anyone tried this tip on the www.hondanighthawks.net/repair.htm page? > > I have the Clymer manual for my 1992 750, but still wasn't clear on where the > "self adjusting cam cam tensioner" was. The author notes a "two minute" > effort. I believe I do have a rattle sound as described, so thought giving > this adjustment might be worthwhile. Opinion? > > Cheers,Eric > > Quote ... > I found a substantial improvement in the sound of the top end of the motor > after taking two minutes to loosen up (then retighten) the self adjusting cam > chain tensioner and let it do its thing. Before this adjustment I was getting > a rattling/loose sound from the top end at about ~4300 rpm. The sound is now > totally gone. I have also pulled the carbs and found the acceleration pump > was mal-adjusted and was not doing its job at all. After the fix (parts > available on eBay for less than $20), I now see four nice little spurts of > fuel down through each of the four carbs whenever the throttle is whipped > open (the design here is to keep the fuel/air mixture from becoming > momentarily too lean when the throttle plate is suddenly opened). With this > repair, I hope to see an even better throttle response now when I get it back > together. --~--~---------~--~----~------------~-------~--~----~ 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 -~----------~----~----~----~------~----~------~--~---
